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-rw-r--r--libX11/specs/libX11/AppC.xml6684
-rw-r--r--libX11/specs/libX11/AppD.xml3778
-rw-r--r--libX11/specs/libX11/CH02.xml124
-rw-r--r--libX11/specs/libX11/CH03.xml8328
-rw-r--r--libX11/specs/libX11/CH04.xml34
-rw-r--r--libX11/specs/libX11/CH05.xml1636
-rw-r--r--libX11/specs/libX11/CH06.xml14896
-rw-r--r--libX11/specs/libX11/CH07.xml6814
-rw-r--r--libX11/specs/libX11/CH08.xml11932
-rw-r--r--libX11/specs/libX11/CH09.xml4032
-rw-r--r--libX11/specs/libX11/CH11.xml5084
-rw-r--r--libX11/specs/libX11/CH12.xml7874
-rw-r--r--libX11/specs/libX11/CH13.xml20706
-rw-r--r--libX11/specs/libX11/CH14.xml10412
-rw-r--r--libX11/specs/libX11/CH15.xml4982
-rw-r--r--libX11/specs/libX11/CH16.xml8320
16 files changed, 57818 insertions, 57818 deletions
diff --git a/libX11/specs/libX11/AppC.xml b/libX11/specs/libX11/AppC.xml
index 16f7dfddb..fb08f8592 100644
--- a/libX11/specs/libX11/AppC.xml
+++ b/libX11/specs/libX11/AppC.xml
@@ -1,3342 +1,3342 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE appendix PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<appendix id="extensions">
-<title>Extensions</title>
-<para>
-<!-- .XE -->
-Because X can evolve by extensions to the core protocol,
-it is important that extensions not be perceived as second-class citizens.
-At some point,
-your favorite extensions may be adopted as additional parts of the
-X Standard.
-</para>
-<para>
-<!-- .LP -->
-Therefore, there should be little to distinguish the use of an extension from
-that of the core protocol.
-To avoid having to initialize extensions explicitly in application programs,
-it is also important that extensions perform lazy evaluations,
-automatically initializing themselves when called for the first time.
-</para>
-<para>
-<!-- .LP -->
-This appendix describes techniques for writing extensions to Xlib that will
-run at essentially the same performance as the core protocol requests.
-</para>
-<!-- .NT -->
-<note><para>
-It is expected that a given extension to X consists of multiple
-requests.
-Defining 10 new features as 10 separate extensions is a bad practice.
-Rather, they should be packaged into a single extension
-and should use minor opcodes to distinguish the requests.
-</para></note>
-<!-- .NE -->
-<para>
-<!-- .LP -->
-The symbols and macros used for writing stubs to Xlib are listed in
-&lt;X11/Xlibint.h&gt; .
-<!-- .SH -->
-Basic Protocol Support Routines
-</para>
-<para>
-The basic protocol requests for extensions are
-<function>XQueryExtension</function>
-and
-<function>XListExtensions</function>.
-</para>
-<indexterm significance="preferred"><primary>XQueryExtension</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XQueryExtension</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *name</parameter></paramdef>
- <paramdef>int<parameter> *major_opcode_return</parameter></paramdef>
- <paramdef>int<parameter> *first_event_return</parameter></paramdef>
- <paramdef>int<parameter> *first_error_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>display</term>
- <listitem>
- <para>Specifies the connection to the X server.</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>name</term>
- <listitem>
- <para>Specifies the extension name.</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>major_opcode_return</term>
- <listitem>
- <para>Returns the major opcode.</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>first_event_return</term>
- <listitem>
- <para>Returns the first event code, if any.</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>first_error_return</term>
- <listitem>
- <para>Returns the first error code, if any.</para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XQueryExtension</function>
-function determines if the named extension is present.
-If the extension is not present,
-<function>XQueryExtension</function>
-returns
-<symbol>False</symbol>;
-otherwise, it returns
-<symbol>True</symbol>.
-If the extension is present,
-<function>XQueryExtension</function>
-returns the major opcode for the extension to major_opcode_return;
-otherwise,
-it returns zero.
-Any minor opcode and the request formats are specific to the
-extension.
-If the extension involves additional event types,
-<function>XQueryExtension</function>
-returns the base event type code to first_event_return;
-otherwise,
-it returns zero.
-The format of the events is specific to the extension.
-If the extension involves additional error codes,
-<function>XQueryExtension</function>
-returns the base error code to first_error_return;
-otherwise,
-it returns zero.
-The format of additional data in the errors is specific to the extension.
-</para>
-<para>
-<!-- .LP -->
-If the extension name is not in the Host Portable Character Encoding
-the result is implementation-dependent.
-Uppercase and lowercase matter;
-the strings ``thing'', ``Thing'', and ``thinG''
-are all considered different names.
-<indexterm significance="preferred"><primary>XListExtensions</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char **<function>XListExtensions</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> *nextensions_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nextensions_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of extensions listed.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XListExtensions</function>
-function returns a list of all extensions supported by the server.
-If the data returned by the server is in the Latin Portable Character Encoding,
-then the returned strings are in the Host Portable Character Encoding.
-Otherwise, the result is implementation-dependent.
-<indexterm significance="preferred"><primary>XFreeExtensionList</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFreeExtensionList</function></funcdef>
- <paramdef>char<parameter> **list</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the list of extension names.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreeExtensionList</function>
-function frees the memory allocated by
-<function>XListExtensions</function>.
-<!-- .SH -->
-Hooking into Xlib
-</para>
-<para>
-<!-- .LP -->
-These functions allow you to hook into the library.
-They are not normally used by application programmers but are used
-by people who need to extend the core X protocol and
-the X library interface.
-The functions, which generate protocol requests for X, are typically
-called stubs.
-</para>
-<para>
-<!-- .LP -->
-In extensions, stubs first should check to see if they have initialized
-themselves on a connection.
-If they have not, they then should call
-<function>XInitExtension</function>
-to attempt to initialize themselves on the connection.
-</para>
-<para>
-<!-- .LP -->
-If the extension needs to be informed of GC/font allocation or
-deallocation or if the extension defines new event types,
-the functions described here allow the extension to be
-called when these events occur.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XExtCodes</structname>
-structure returns the information from
-<function>XInitExtension</function>
-and is defined in
-&lt;X11/Xlib.h&gt; :
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XExtCodes</primary></indexterm>
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<synopsis>
-typedef struct _XExtCodes { /* public to extension, cannot be changed */
- int extension; /* extension number */
- int major_opcode; /* major op-code assigned by server */
- int first_event; /* first event number for the extension */
- int first_error; /* first error number for the extension */
-} XExtCodes;
-</synopsis>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>XInitExtension</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XExtCodes *<function>XInitExtension</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *name</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XInitExtension</function>
-function determines if the named extension exists.
-Then, it allocates storage for maintaining the
-information about the extension on the connection,
-chains this onto the extension list for the connection,
-and returns the information the stub implementor will need to access
-the extension.
-If the extension does not exist,
-<function>XInitExtension</function>
-returns NULL.
-</para>
-<para>
-<!-- .LP -->
-If the extension name is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-Uppercase and lowercase matter;
-the strings ``thing'', ``Thing'', and ``thinG''
-are all considered different names.
-</para>
-<para>
-<!-- .LP -->
-The extension number in the
-<structname>XExtCodes</structname>
-structure is
-needed in the other calls that follow.
-This extension number is unique only to a single connection.
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XAddExtension</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XExtCodes *<function>XAddExtension</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-For local Xlib extensions, the
-<function>XAddExtension</function>
-function allocates the
-<structname>XExtCodes</structname>
-structure, bumps the extension number count,
-and chains the extension onto the extension list.
-(This permits extensions to Xlib without requiring server extensions.)
-<!-- .SH -->
-Hooks into the Library
-</para>
-<para>
-<!-- .LP -->
-These functions allow you to define procedures that are to be
-called when various circumstances occur.
-The procedures include the creation of a new GC for a connection,
-the copying of a GC, the freeing of a GC, the creating and freeing of fonts,
-the conversion of events defined by extensions to and from wire
-format, and the handling of errors.
-</para>
-<para>
-<!-- .LP -->
-All of these functions return the previous procedure defined for this
-extension.
-<indexterm significance="preferred"><primary>XESetCloseDisplay</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XESetCloseDisplay</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> extension</parameter></paramdef>
- <paramdef>int<parameter> (*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>extension</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension number.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when the display is closed.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XESetCloseDisplay</function>
-function defines a procedure to be called whenever
-<function>XCloseDisplay</function>
-is called.
-It returns any previously defined procedure, usually NULL.
-</para>
-<para>
-<!-- .LP -->
-When
-<function>XCloseDisplay</function>
-is called,
-your procedure is called
-with these arguments:
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-</para>
-<para>
-<indexterm significance="preferred"><primary>XESetCreateGC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int *<function>XESetCreateGC</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> extension</parameter></paramdef>
- <paramdef>int<parameter> (*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>extension</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension number.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when a GC is closed.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XESetCreateGC</function>
-function defines a procedure to be called whenever
-a new GC is created.
-It returns any previously defined procedure, usually NULL.
-</para>
-<para>
-<!-- .LP -->
-When a GC is created,
-your procedure is called with these arguments:
-<!-- .LP -->
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>GC <parameter>gc</parameter></paramdef>
- <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-</para>
-<indexterm significance="preferred"><primary>XESetCopyGC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int *<function>XESetCopyGC</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> extension</parameter></paramdef>
- <paramdef>int<parameter> (*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>extension</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension number.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when GC components are copied.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XESetCopyGC</function>
-function defines a procedure to be called whenever
-a GC is copied.
-It returns any previously defined procedure, usually NULL.
-</para>
-<para>
-<!-- .LP -->
-When a GC is copied,
-your procedure is called with these arguments:
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>GC <parameter>gc</parameter></paramdef>
- <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-</para>
-<funcsynopsis>
-<funcprototype>
- <funcdef>int *<function>XESetFreeGC</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> extension</parameter></paramdef>
- <paramdef>int<parameter> (*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>extension</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension number.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when a GC is freed.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-The
-<function>XESetFreeGC</function>
-function defines a procedure to be called whenever
-a GC is freed.
-It returns any previously defined procedure, usually NULL.
-</para>
-<para>
-<!-- .LP -->
-When a GC is freed,
-your procedure is called with these arguments:
-<!-- .LP -->
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<!-- .R -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>GC <parameter>gc</parameter></paramdef>
- <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>XESetCreateFont</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int *<function>XESetCreateFont</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> extension</parameter></paramdef>
- <paramdef>int<parameter> (*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>extension</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension number.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when a font is created.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XESetCreateFont</function>
-function defines a procedure to be called whenever
-<function>XLoadQueryFont</function>
-and
-<function>XQueryFont</function>
-are called.
-It returns any previously defined procedure, usually NULL.
-</para>
-<para>
-<!-- .LP -->
-When
-<function>XLoadQueryFont</function>
-or
-<function>XQueryFont</function>
-is called,
-your procedure is called with these arguments:
-<!-- .LP -->
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<!-- .R -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>XFontStruct *<parameter>fs</parameter></paramdef>
- <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>XESetFreeFont</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int *<function>XESetFreeFont</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> extension</parameter></paramdef>
- <paramdef>int<parameter> (*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>extension</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension number.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when a font is freed.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XESetFreeFont</function>
-function defines a procedure to be called whenever
-<function>XFreeFont</function>
-is called.
-It returns any previously defined procedure, usually NULL.
-</para>
-<para>
-<!-- .LP -->
-When
-<function>XFreeFont</function>
-is called, your procedure is called with these arguments:
-<!-- .LP -->
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<!-- .R -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>XFontStruct *<parameter>fs</parameter></paramdef>
- <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XESetWireToEvent</function>
-and
-<function>XESetEventToWire</function>
-functions allow you to define new events to the library.
-An
-<structname>XEvent</structname>
-structure always has a type code (type
-<type>int</type>)
-as the first component.
-This uniquely identifies what kind of event it is.
-The second component is always the serial number (type
-<type>unsigned</type>
-<type>long</type>)
-of the last request processed by the server.
-The third component is always a Boolean (type
-<type>Bool</type>)
-indicating whether the event came from a
-<systemitem>SendEvent</systemitem>
-protocol request.
-The fourth component is always a pointer to the display
-the event was read from.
-The fifth component is always a resource ID of one kind or another,
-usually a window, carefully selected to be useful to toolkit dispatchers.
-The fifth component should always exist, even if
-the event does not have a natural destination;
-if there is no value
-from the protocol to put in this component, initialize it to zero.
-<!-- .NT -->
-There is an implementation limit such that your host event
-structure size cannot be bigger than the size of the
-<structname>XEvent</structname>
-union of structures.
-There also is no way to guarantee that more than 24 elements or 96 characters
-in the structure will be fully portable between machines.
-<!-- .NE -->
-<indexterm significance="preferred"><primary>XESetWireToEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int *<function>XESetWireToEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> event_number</parameter></paramdef>
- <paramdef>Status<parameter> (*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_number</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event code.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when converting an event.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XESetWireToEvent</function>
-function defines a procedure to be called when an event
-needs to be converted from wire format
-(<structname>xEvent</structname>)
-to host format
-(<structname>XEvent</structname>).
-The event number defines which protocol event number to install a
-conversion procedure for.
-<function>XESetWireToEvent</function>
-returns any previously defined procedure.
-<!-- .NT -->
-You can replace a core event conversion function with one
-of your own, although this is not encouraged.
-It would, however, allow you to intercept a core event
-and modify it before being placed in the queue or otherwise examined.
-<!-- .NE -->
-When Xlib needs to convert an event from wire format to host
-format, your procedure is called with these arguments:
-<!-- .LP -->
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<!-- .R -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>XEvent *<parameter>re</parameter></paramdef>
- <paramdef>xEvent *<parameter>event</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .LP -->
-<!-- .eM -->
-Your procedure must return status to indicate if the conversion succeeded.
-The re argument is a pointer to where the host format event should be stored,
-and the event argument is the 32-byte wire event structure.
-In the
-<structname>XEvent</structname>
-structure you are creating,
-you must fill in the five required members of the event structure.
-You should fill in the type member with the type specified for the
-<structname>xEvent</structname>
-structure.
-You should copy all other members from the
-<structname>xEvent</structname>
-structure (wire format) to the
-<structname>XEvent</structname>
-structure (host format).
-Your conversion procedure should return
-<symbol>True</symbol>
-if the event should be placed in the queue or
-<symbol>False</symbol>
-if it should not be placed in the queue.
-</para>
-<para>
-<!-- .LP -->
-To initialize the serial number component of the event, call
-<function>_XSetLastRequestRead</function>
-with the event and use the return value.
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>_XSetLastRequestRead</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>unsigned long<function>_XSetLastRequestRead</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>xGenericReply<parameter> *rep</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>rep</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the wire event structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>_XSetLastRequestRead</function>
-function computes and returns a complete serial number from the partial
-serial number in the event.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XESetEventToWire</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status *<function>XESetEventToWire</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> event_number</parameter></paramdef>
- <paramdef>int<parameter> (*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_number</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event code.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when converting an event.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XESetEventToWire</function>
-function defines a procedure to be called when an event
-needs to be converted from host format
-(<structname>XEvent</structname>)
-to wire format
-(<structname>xEvent</structname>)
-form.
-The event number defines which protocol event number to install a
-conversion procedure for.
-<function>XESetEventToWire</function>
-returns any previously defined procedure.
-It returns zero if the conversion fails or nonzero otherwise.
-<!-- .NT -->
-You can replace a core event conversion function with one
-of your own, although this is not encouraged.
-It would, however, allow you to intercept a core event
-and modify it before being sent to another client.
-<!-- .NE -->
-When Xlib needs to convert an event from host format to wire format,
-your procedure is called with these arguments:
-<!-- .LP -->
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<!-- .R -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>XEvent *<parameter>re</parameter></paramdef>
- <paramdef>xEvent *<parameter>event</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .LP -->
-<!-- .eM -->
-The re argument is a pointer to the host format event,
-and the event argument is a pointer to where the 32-byte wire event
-structure should be stored.
-You should fill in the type with the type from the
-<structname>XEvent</structname>
-structure.
-All other members then should be copied from the host format to the
-<structname>xEvent</structname>
-structure.
-<indexterm significance="preferred"><primary>XESetWireToError</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool *<function>XESetWireToError</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> error_number</parameter></paramdef>
- <paramdef>Bool<parameter> (*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>error_number</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the error code.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when an error is received.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XESetWireToError</function>
-function defines a procedure to be called when an extension
-error needs to be converted from wire format to host format.
-The error number defines which protocol error code to install
-the conversion procedure for.
-<function>XESetWireToError</function>
-returns any previously defined procedure.
-</para>
-<para>
-<!-- .LP -->
-Use this function for extension errors that contain additional error values
-beyond those in a core X error, when multiple wire errors must be combined
-into a single Xlib error, or when it is necessary to intercept an
-X error before it is otherwise examined.
-</para>
-<para>
-<!-- .LP -->
-When Xlib needs to convert an error from wire format to host format,
-the procedure is called with these arguments:
-<!-- .LP -->
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<!-- .R -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>XErrorEvent *<parameter>he</parameter></paramdef>
- <paramdef>xError *<parameter>we</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .LP -->
-<!-- .eM -->
-The he argument is a pointer to where the host format error should be stored.
-The structure pointed at by he is guaranteed to be as large as an
-<structname>XEvent</structname>
-structure and so can be cast to a type larger than an
-<structname>XErrorEvent</structname>
-to store additional values.
-If the error is to be completely ignored by Xlib
-(for example, several protocol error structures will be combined into
-one Xlib error),
-then the function should return
-<symbol>False</symbol>;
-otherwise, it should return
-<symbol>True</symbol>.
-<indexterm significance="preferred"><primary>XESetError</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int *<function>XESetError</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> extension</parameter></paramdef>
- <paramdef>int<parameter> (*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>extension</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension number.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when an error is received.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Inside Xlib, there are times that you may want to suppress the
-calling of the external error handling when an error occurs.
-This allows status to be returned on a call at the cost of the call
-being synchronous (though most such functions are query operations, in any
-case, and are typically programmed to be synchronous).
-</para>
-<para>
-<!-- .LP -->
-When Xlib detects a protocol error in
-<function>_XReply</function>,
-it calls your procedure with these arguments:
-<!-- .LP -->
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<!-- .R -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>xError *<parameter>err</parameter></paramdef>
- <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
- <paramdef>int *<parameter>ret_code</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .LP -->
-<!-- .eM -->
-The err argument is a pointer to the 32-byte wire format error.
-The codes argument is a pointer to the extension codes structure.
-The ret_code argument is the return code you may want
-<function>_XReply</function>
-returned to.
-</para>
-<para>
-<!-- .LP -->
-If your procedure returns a zero value,
-the error is not suppressed, and
-the client's error handler is called.
-(For further information, see section 11.8.2.)
-If your procedure returns nonzero,
-the error is suppressed, and
-<function>_XReply</function>
-returns the value of ret_code.
-<indexterm significance="preferred"><primary>XESetErrorString</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XESetErrorString</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> extension</parameter></paramdef>
- <paramdef>char<parameter> *(*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>extension</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension number.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call to obtain an error string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetErrorText</function>
-function returns a string to the user for an error.
-<function>XESetErrorString</function>
-allows you to define a procedure to be called that
-should return a pointer to the error message.
-The following is an example.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<!-- .R -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>int <parameter>code</parameter></paramdef>
- <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
- <paramdef>char *<parameter>buffer</parameter></paramdef>
- <paramdef>int <parameter>nbytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .LP -->
-<!-- .eM -->
-Your procedure is called with the error code for every error detected.
-You should copy nbytes of a null-terminated string containing the
-error message into buffer.
-<indexterm significance="preferred"><primary>XESetPrintErrorValues</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void *<function>XESetPrintErrorValues</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> extension</parameter></paramdef>
- <paramdef>void<parameter> (*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>extension</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension number.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when an error is printed.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XESetPrintErrorValues</function>
-function defines a procedure to be called when an extension
-error is printed, to print the error values.
-Use this function for extension errors that contain additional error values
-beyond those in a core X error.
-It returns any previously defined procedure.
-</para>
-<para>
-<!-- .LP -->
-When Xlib needs to print an error,
-the procedure is called with these arguments:
-<!-- .LP -->
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<!-- .R -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>XErrorEvent *<parameter>ev</parameter></paramdef>
- <paramdef>void *<parameter>fp</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .LP -->
-<!-- .eM -->
-The structure pointed at by ev is guaranteed to be as large as an
-<structname>XEvent</structname>
-structure and so can be cast to a type larger than an
-<structname>XErrorEvent</structname>
-to obtain additional values set by using
-<function>XESetWireToError</function>.
-The underlying type of the fp argument is system dependent;
-on a <acronym>POSIX</acronym>-compliant system, fp should be cast to type FILE*.
-<indexterm significance="preferred"><primary>XESetFlushGC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int *<function>XESetFlushGC</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> extension</parameter></paramdef>
- <paramdef>int<parameter> *(*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>extension</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension number.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when a GC is flushed.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The procedure set by the
-<function>XESetFlushGC</function>
-function has the same interface as the procedure set by the
-<function>XESetCopyGC</function>
-function, but is called when a GC cache needs to be updated in the server.
-<indexterm significance="preferred"><primary>XESetBeforeFlush</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int *<function>XESetCopyGC</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> extension</parameter></paramdef>
- <paramdef>int<parameter> *(*proc)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>extension</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension number.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to call when a buffer is flushed.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XESetBeforeFlush</function>
-function defines a procedure to be called when data is about to be
-sent to the server. When data is about to be sent, your procedure is
-called one or more times with these arguments:
-<!-- .LP -->
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<!-- .R -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>(*<replaceable>proc</replaceable>)</function></funcdef>
- <paramdef>Display *<parameter>display</parameter></paramdef>
- <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
- <paramdef>char *<parameter>data</parameter></paramdef>
- <paramdef>long <parameter>len</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .LP -->
-<!-- .eM -->
-The data argument specifies a portion of the outgoing data buffer,
-and its length in bytes is specified by the len argument.
-Your procedure must not alter the contents of the data and must not
-do additional protocol requests to the same display.
-<!-- .SH -->
-Hooks onto Xlib Data Structures
-</para>
-<para>
-<!-- .LP -->
-Various Xlib data structures have provisions for extension procedures
-to chain extension supplied data onto a list.
-These structures are
-<structname>GC</structname>,
-<structname>Visual</structname>,
-<type>Screen</type>,
-<structname>ScreenFormat</structname>,
-<type>Display</type>,
-and
-<structname>XFontStruct</structname>.
-Because the list pointer is always the first member in the structure,
-a single set of procedures can be used to manipulate the data
-on these lists.
-</para>
-<para>
-<!-- .LP -->
-The following structure is used in the functions in this section
-and is defined in
-&lt;X11/Xlib.h&gt;
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XExtData</primary></indexterm>
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<synopsis>
-typedef struct _XExtData {
- int number; /* number returned by XInitExtension */
- struct _XExtData *next; /* next item on list of data for structure */
- int (*free_private)(); /* if defined, called to free private */
- XPointer private_data; /* data private to this extension. */
-} XExtData;
-</synopsis>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-When any of the data structures listed above are freed,
-the list is walked, and the structure's free procedure (if any) is called.
-If free is NULL,
-then the library frees both the data pointed to by the private_data member
-and the structure itself.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<!-- .TA .5i -->
-<!-- .ta .5i -->
-<synopsis>
-union { Display *display;
- GC gc;
- Visual *visual;
- Screen *screen;
- ScreenFormat *pixmap_format;
- XFontStruct *font } XEDataObject;
-</synopsis>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>XEHeadOfExtensionList</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XExtData **<function>XEHeadOfExtensionList</function></funcdef>
- <paramdef>XEDataObject<parameter> object</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>object</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the object.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XEHeadOfExtensionList</function>
-function returns a pointer to the list of extension structures attached
-to the specified object.
-In concert with
-<function>XAddToExtensionList</function>,
-<function>XEHeadOfExtensionList</function>
-allows an extension to attach arbitrary data to any of the structures
-of types contained in
-<structname>XEDataObject</structname>.
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XAddToExtensionList</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XAddToExtensionList</function></funcdef>
- <paramdef>XExtData<parameter> **structure</parameter></paramdef>
- <paramdef>XExtData<parameter> *ext_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>structure</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ext_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension data structure to add.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The structure argument is a pointer to one of the data structures
-enumerated above.
-You must initialize ext_data-&gt;number with the extension number
-before calling this function.
-<indexterm significance="preferred"><primary>XFindOnExtensionList</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XExtData *<function>XFindOnExtensionList</function></funcdef>
- <paramdef>struct_XExtData<parameter> **structure</parameter></paramdef>
- <paramdef>int<parameter> number</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>structure</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>number</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the extension number from
-<function>XInitExtension</function>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFindOnExtensionList</function>
-function returns the first extension data structure
-for the extension numbered number.
-It is expected that an extension will add at most one extension
-data structure to any single data structure's extension data list.
-There is no way to find additional structures.
-</para>
-<para>
-<!-- .LP -->
-The
-<function>XAllocID</function>
-macro, which allocates and returns a resource ID, is defined in
-&lt;X11/Xlib.h&gt;.
-<indexterm significance="preferred"><primary>XAllocID</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XAllocID</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-This macro is a call through the
-<type>Display</type>
-structure to an internal resource ID allocator.
-It returns a resource ID that you can use when creating new resources.
-</para>
-<para>
-<!-- .LP -->
-The
-<function>XAllocIDs</function>
-macro allocates and returns an array of resource ID.
-<indexterm significance="preferred"><primary>XAllocIDs</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XAllocIDs</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XID<parameter> *ids_return</parameter></paramdef>
- <paramdef>int<parameter> count</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ids_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the resource IDs.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>rep</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of resource IDs requested.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-This macro is a call through the
-<type>Display</type>
-structure to an internal resource ID allocator.
-It returns resource IDs to the array supplied by the caller.
-To correctly handle automatic reuse of resource IDs, you must call
-<function>XAllocIDs</function>
-when requesting multiple resource IDs. This call might generate
-protocol requests.
-<!-- .SH -->
-GC Caching
-</para>
-<para>
-<!-- .LP -->
-GCs are cached by the library to allow merging of independent change
-requests to the same GC into single protocol requests.
-This is typically called a write-back cache.
-Any extension procedure whose behavior depends on the contents of a GC
-must flush the GC cache to make sure the server has up-to-date contents
-in its GC.
-</para>
-<para>
-<!-- .LP -->
-The
-<function>FlushGC</function>
-macro checks the dirty bits in the library's GC structure and calls
-<function>_XFlushGCCache</function>
-if any elements have changed.
-The
-<function>FlushGC</function>
-macro is defined as follows:
-<indexterm significance="preferred"><primary>FlushGC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>FlushGC</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Note that if you extend the GC to add additional resource ID components,
-you should ensure that the library stub sends the change request immediately.
-This is because a client can free a resource immediately after
-using it, so if you only stored the value in the cache without
-forcing a protocol request, the resource might be destroyed before being
-set into the GC.
-You can use the
-<function>_XFlushGCCache</function>
-procedure
-to force the cache to be flushed.
-The
-<function>_XFlushGCCache</function>
-procedure
-is defined as follows:
-<indexterm significance="preferred"><primary>_XFlushGCCache</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>_XFlushGCCache</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .SH -->
-Graphics Batching
-</para>
-<para>
-<!-- .LP -->
-If you extend X to add more poly graphics primitives, you may be able to
-take advantage of facilities in the library to allow back-to-back
-single calls to be transformed into poly requests.
-This may dramatically improve performance of programs that are not
-written using poly requests.
-A pointer to an
-<structname>xReq</structname>,
-called last_req in the display structure, is the last request being processed.
-By checking that the last request
-type, drawable, gc, and other options are the same as the new one
-and that there is enough space left in the buffer, you may be able
-to just extend the previous graphics request by extending the length
-field of the request and appending the data to the buffer.
-This can improve performance by five times or more in naive programs.
-For example, here is the source for the
-<function>XDrawPoint</function>
-stub.
-(Writing extension stubs is discussed in the next section.)
-</para>
-<!-- .sM -->
-<!-- .nf -->
-<programlisting>
-#include &lt;X11/Xlibint.h&gt;
-
-/* precompute the maximum size of batching request allowed */
-
-static int size = sizeof(xPolyPointReq) + EPERBATCH * sizeof(xPoint);
-
-XDrawPoint(dpy, d, gc, x, y)
- register Display *dpy;
- Drawable d;
- GC gc;
- int x, y; /* INT16 */
-{
- xPoint *point;
- LockDisplay(dpy);
- FlushGC(dpy, gc);
- {
- register xPolyPointReq *req = (xPolyPointReq *) dpy-&gt;last_req;
- /* if same as previous request, with same drawable, batch requests */
- if (
- (req-&gt;reqType == X_PolyPoint)
- &amp;&amp; (req-&gt;drawable == d)
- &amp;&amp; (req-&gt;gc == gc-&gt;gid)
- &amp;&amp; (req-&gt;coordMode == CoordModeOrigin)
- &amp;&amp; ((dpy-&gt;bufptr + sizeof (xPoint)) &lt;= dpy-&gt;bufmax)
- &amp;&amp; (((char *)dpy-&gt;bufptr - (char *)req) &lt; size) ) {
- point = (xPoint *) dpy-&gt;bufptr;
- req-&gt;length += sizeof (xPoint) &gt;&gt; 2;
- dpy-&gt;bufptr += sizeof (xPoint);
- }
-
- else {
- GetReqExtra(PolyPoint, 4, req); /* 1 point = 4 bytes */
- req-&gt;drawable = d;
- req-&gt;gc = gc-&gt;gid;
- req-&gt;coordMode = CoordModeOrigin;
- point = (xPoint *) (req + 1);
- }
- point-&gt;x = x;
- point-&gt;y = y;
- }
- UnlockDisplay(dpy);
- SyncHandle();
-}
-</programlisting>
-<!-- .fi -->
-<para>
-<!-- .LP -->
-<!-- .eM -->
-To keep clients from generating very long requests that may monopolize the
-server,
-there is a symbol defined in
-&lt;X11/Xlibint.h&gt;
-of EPERBATCH on the number of requests batched.
-Most of the performance benefit occurs in the first few merged requests.
-Note that
-<function>FlushGC</function>
-is called <emphasis remap='I'>before</emphasis> picking up the value of last_req,
-because it may modify this field.
-<!-- .SH -->
-Writing Extension Stubs
-</para>
-<para>
-<!-- .LP -->
-All X requests always contain the length of the request,
-expressed as a 16-bit quantity of 32 bits.
-This means that a single request can be no more than 256K bytes in
-length.
-Some servers may not support single requests of such a length.
-The value of dpy-&gt;max_request_size contains the maximum length as
-defined by the server implementation.
-For further information,
-see ``X Window System Protocol.''
-<!-- .SH -->
-Requests, Replies, and Xproto.h
-</para>
-<para>
-<!-- .LP -->
-The
-&lt;X11/Xproto.h&gt;
-file contains three sets of definitions that
-are of interest to the stub implementor:
-request names, request structures, and reply structures.
-</para>
-<para>
-<!-- .LP -->
-You need to generate a file equivalent to
-&lt;X11/Xproto.h&gt;
-for your extension and need to include it in your stub procedure.
-Each stub procedure also must include
-&lt;X11/Xlibint.h&gt; .
-</para>
-<para>
-<!-- .LP -->
-The identifiers are deliberately chosen in such a way that, if the
-request is called X_DoSomething, then its request structure is
-xDoSomethingReq, and its reply is xDoSomethingReply.
-The GetReq family of macros, defined in
-&lt;X11/Xlibint.h&gt; ,
-takes advantage of this naming scheme.
-</para>
-<para>
-<!-- .LP -->
-For each X request,
-there is a definition in
-&lt;X11/Xproto.h&gt;
-that looks similar to this:
-</para>
-<para>
-<!-- .LP -->
-<!-- .R -->
-<programlisting>
-#define X_DoSomething 42
-</programlisting>
-In your extension header file,
-this will be a minor opcode,
-instead of a major opcode.
-<!-- .SH -->
-Request Format
-</para>
-<para>
-<!-- .LP -->
-Every request contains an 8-bit major opcode and a 16-bit length field
-expressed in units of 4 bytes.
-Every request consists of 4 bytes of header
-(containing the major opcode, the length field, and a data byte) followed by
-zero or more additional bytes of data.
-The length field defines the total length of the request, including the header.
-The length field in a request must equal the minimum length required to contain
-the request.
-If the specified length is smaller or larger than the required length,
-the server should generate a
-<errorname>BadLength</errorname>
-error.
-Unused bytes in a request are not required to be zero.
-Extensions should be designed in such a way that long protocol requests
-can be split up into smaller requests,
-if it is possible to exceed the maximum request size of the server.
-The protocol guarantees the maximum request size to be no smaller than
-4096 units (16384 bytes).
-</para>
-<para>
-<!-- .LP -->
-Major opcodes 128 through 255 are reserved for extensions.
-Extensions are intended to contain multiple requests,
-so extension requests typically have an additional minor opcode encoded
-in the second data byte in the request header,
-but the placement and interpretation of this minor opcode as well as all
-other fields in extension requests are not defined by the core protocol.
-Every request is implicitly assigned a sequence number (starting with one)
-used in replies, errors, and events.
-</para>
-<para>
-<!-- .LP -->
-To help but not cure portability problems to certain machines, the
-<symbol>B16</symbol>
-and
-<symbol>B32</symbol>
-macros have been defined so that they can become bitfield specifications
-on some machines.
-For example, on a Cray,
-these should be used for all 16-bit and 32-bit quantities, as discussed below.
-</para>
-<para>
-<!-- .LP -->
-Most protocol requests have a corresponding structure typedef in
-&lt;X11/Xproto.h&gt;,
-which looks like:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>xDoSomethingReq</primary></indexterm>
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<synopsis>
-typedef struct _DoSomethingReq {
- CARD8 reqType; /* X_DoSomething */
- CARD8 someDatum; /* used differently in different requests */
- CARD16 length B16; /* total # of bytes in request, divided by 4 */
- ...
- /* request-specific data */
- ...
-} xDoSomethingReq;
-</synopsis>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If a core protocol request has a single 32-bit argument,
-you need not declare a request structure in your extension header file.
-Instead, such requests use the
-<structname>xResourceReq</structname>
-structure in
-&lt;X11/Xproto.h&gt;.
-This structure is used for any request whose single argument is a
-<type>Window</type>,
-<type>Pixmap</type>,
-<type>Drawable</type>,
-<type>GContext</type>,
-<type>Font</type>,
-<type>Cursor</type>,
-<type>Colormap</type>,
-<type>Atom</type>,
-or
-<type>VisualID</type>.
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>xResourceReq</primary></indexterm>
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<synopsis>
-typedef struct _ResourceReq {
- CARD8 reqType; /* the request type, e.g. X_DoSomething */
- BYTE pad; /* not used */
- CARD16 length B16; /* 2 (= total # of bytes in request, divided by 4) */
- CARD32 id B32; /* the Window, Drawable, Font, GContext, etc. */
-} xResourceReq;
-</synopsis>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If convenient,
-you can do something similar in your extension header file.
-</para>
-<para>
-<!-- .LP -->
-In both of these structures,
-the reqType field identifies the type of the request (for example,
-X_MapWindow or X_CreatePixmap).
-The length field tells how long the request is
-in units of 4-byte longwords.
-This length includes both the request structure itself and any
-variable-length data, such as strings or lists, that follow the
-request structure.
-Request structures come in different sizes,
-but all requests are padded to be multiples of four bytes long.
-</para>
-<para>
-<!-- .LP -->
-A few protocol requests take no arguments at all.
-Instead, they use the
-<structname>xReq</structname>
-structure in
-&lt;X11/Xproto.h&gt;,
-which contains only a reqType and a length (and a pad byte).
-</para>
-<para>
-<!-- .LP -->
-If the protocol request requires a reply,
-then
-&lt;X11/Xproto.h&gt;
-also contains a reply structure typedef:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>xDoSomethingReply</primary></indexterm>
-<!-- .sM -->
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-<synopsis>
-typedef struct _DoSomethingReply {
- BYTE type; /* always X_Reply */
- BYTE someDatum; /* used differently in different requests */
- CARD16 sequenceNumber B16; /* # of requests sent so far */
- CARD32 length B32; /* # of additional bytes, divided by 4 */
- ...
- /* request-specific data */
- ...
-} xDoSomethingReply;
-</synopsis>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Most of these reply structures are 32 bytes long.
-If there are not that many reply values,
-then they contain a sufficient number of pad fields
-to bring them up to 32 bytes.
-The length field is the total number of bytes in the request minus 32,
-divided by 4.
-This length will be nonzero only if:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The reply structure is followed by variable-length data,
-such as a list or string.
- </para>
- </listitem>
- <listitem>
- <para>
-The reply structure is longer than 32 bytes.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Only
-<systemitem>GetWindowAttributesl</systemitem>,
-<systemitem>QueryFont</systemitem>,
-<systemitem>QueryKeymap</systemitem>,
-and
-<systemitem>GetKeyboardControl</systemitem>
-have reply structures longer than 32 bytes in the core protocol.
-</para>
-<para>
-<!-- .LP -->
-A few protocol requests return replies that contain no data.
-&lt;X11/Xproto.h&gt;
-does not define reply structures for these.
-Instead, they use the
-<structname>xGenericReply</structname>
-structure, which contains only a type, length,
-and sequence number (and sufficient padding to make it 32 bytes long).
-<!-- .SH -->
-Starting to Write a Stub Procedure
-</para>
-<para>
-<!-- .LP -->
-An Xlib stub procedure should start like this:
-</para>
-<para>
-<!-- .LP -->
-<!-- .R -->
-<programlisting>
-#include "&lt;X11/Xlibint.h&gt;
-
-XDoSomething (arguments, ... )
-/* argument declarations */
-{
-
-register XDoSomethingReq *req;
-...
-</programlisting>
-If the protocol request has a reply,
-then the variable declarations should include the reply structure for the request.
-The following is an example:
-</para>
-<para>
-<!-- .LP -->
-<!-- .R -->
-<programlisting>
-xDoSomethingReply rep;
-</programlisting>
-<!-- .SH -->
-Locking Data Structures
-</para>
-<para>
-<!-- .LP -->
-To lock the display structure for systems that
-want to support multithreaded access to a single display connection,
-each stub will need to lock its critical section.
-Generally, this section is the point from just before the appropriate GetReq
-call until all arguments to the call have been stored into the buffer.
-The precise instructions needed for this locking depend upon the machine
-architecture.
-Two calls, which are generally implemented as macros, have been provided.
-<indexterm significance="preferred"><primary>LockDisplay</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>LockDisplay</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>UnlockDisplay</primary></indexterm>
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>UnlockDisplay</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .SH -->
-Sending the Protocol Request and Arguments
-</para>
-<para>
-<!-- .LP -->
-After the variable declarations,
-a stub procedure should call one of four macros defined in
-&lt;X11/Xlibint.h&gt;:
-<function>GetReq</function>,
-<function>GetReqExtra</function>,
-<function>GetResReq</function>,
-or
-<function>GetEmptyReq</function>.
-All of these macros take, as their first argument,
-the name of the protocol request as declared in
-&lt;X11/Xproto.h&gt;
-except with X_ removed.
-Each one declares a
-<type>Display</type>
-structure pointer,
-called dpy, and a pointer to a request structure, called req,
-which is of the appropriate type.
-The macro then appends the request structure to the output buffer,
-fills in its type and length field, and sets req to point to it.
-</para>
-<para>
-<!-- .LP -->
-If the protocol request has no arguments (for instance, X_GrabServer),
-then use
-<function>GetEmptyReq</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .R -->
-<programlisting>
-GetEmptyReq (DoSomething, req);
-</programlisting>
-If the protocol request has a single 32-bit argument (such as a
-<type>Pixmap</type>,
-<type>Window</type>,
-<type>Drawable</type>,
-<type>Atom</type>,
-and so on),
-then use
-<function>GetResReq</function>.
-The second argument to the macro is the 32-bit object.
-<symbol>X_MapWindow</symbol>
-is a good example.
-</para>
-<para>
-<!-- .LP -->
-<!-- .R -->
-<programlisting>
-GetResReq (DoSomething, rid, req);
-</programlisting>
-The rid argument is the
-<type>Pixmap</type>,
-<type>Window</type>,
-or other resource ID.
-</para>
-<para>
-<!-- .LP -->
-If the protocol request takes any other argument list,
-then call
-<function>GetReq</function>.
-After the
-<function>GetReq</function>,
-you need to set all the other fields in the request structure,
-usually from arguments to the stub procedure.
-</para>
-<para>
-<!-- .LP -->
-<!-- .R -->
-<programlisting>
-GetReq (DoSomething, req);
-/* fill in arguments here */
-req-&gt;arg1 = arg1;
-req-&gt;arg2 = arg2;
-...
-</programlisting>
-A few stub procedures (such as
-<function>XCreateGC</function>
-and
-<function>XCreatePixmap</function>)
-return a resource ID to the caller but pass a resource ID as an argument
-to the protocol request.
-Such procedures use the macro
-<function>XAllocID</function>
-to allocate a resource ID from the range of IDs
-that were assigned to this client when it opened the connection.
-</para>
-<para>
-<!-- .LP -->
-<!-- .R -->
-<programlisting>
-rid = req-&gt;rid = XAllocID();
-...
-return (rid);
-</programlisting>
-Finally, some stub procedures transmit a fixed amount of variable-length
-data after the request.
-Typically, these procedures (such as
-<function>XMoveWindow</function>
-and
-<function>XSetBackground</function>)
-are special cases of more general functions like
-<function>XMoveResizeWindow</function>
-and
-<function>XChangeGC</function>.
-These procedures use
-<function>GetReqExtra</function>,
-which is the same as
-<function>GetReq</function>
-except that it takes an additional argument (the number of
-extra bytes to allocate in the output buffer after the request structure).
-This number should always be a multiple of four.
-<!-- .SH -->
-Variable Length Arguments
-</para>
-<para>
-<!-- .LP -->
-Some protocol requests take additional variable-length data that
-follow the
-<type>xDoSomethingReq</type>
-structure.
-The format of this data varies from request to request.
-Some requests require a sequence of 8-bit bytes,
-others a sequence of 16-bit or 32-bit entities,
-and still others a sequence of structures.
-</para>
-<para>
-<!-- .LP -->
-It is necessary to add the length of any variable-length data to the
-length field of the request structure.
-That length field is in units of 32-bit longwords.
-If the data is a string or other sequence of 8-bit bytes,
-then you must round the length up and shift it before adding:
-</para>
-<para>
-<!-- .LP -->
-<!-- .R -->
-<programlisting>
-req-&gt;length += (nbytes+3)&gt;&gt;2;
-</programlisting>
-To transmit variable-length data, use the
-<function>Data</function>
-macros.
-If the data fits into the output buffer,
-then this macro copies it to the buffer.
-If it does not fit, however,
-the
-<function>Data</function>
-macro calls
-<function>_XSend</function>,
-which transmits first the contents of the buffer and then your data.
-The
-<function>Data</function>
-macros take three arguments:
-the display, a pointer to the beginning of the data,
-and the number of bytes to be sent.
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>Data</function></funcdef>
- <paramdef><parameter> display</parameter></paramdef>
- <paramdef>(char<parameter> *</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>Data</function>,
-<function>Data16</function>,
-and
-<function>Data32</function>
-are macros that may use their last argument
-more than once, so that argument should be a variable rather than
-an expression such as ``nitems*sizeof(item)''.
-You should do that kind of computation in a separate statement before calling
-them.
-Use the appropriate macro when sending byte, short, or long data.
-</para>
-<para>
-<!-- .LP -->
-If the protocol request requires a reply,
-then call the procedure
-<function>_XSend</function>
-instead of the
-<function>Data</function>
-macro.
-<function>_XSend</function>
-takes the same arguments, but because it sends your data immediately instead of
-copying it into the output buffer (which would later be flushed
-anyway by the following call on
-<function>_XReply</function>),
-it is faster.
-<!-- .SH -->
-Replies
-</para>
-<para>
-<!-- .LP -->
-If the protocol request has a reply,
-then call
-<function>_XReply</function>
-after you have finished dealing with
-all the fixed-length and variable-length arguments.
-<function>_XReply</function>
-flushes the output buffer and waits for an
-<structname>xReply</structname>
-packet to arrive.
-If any events arrive in the meantime,
-<function>_XReply</function>
-places them in the queue for later use.
-<indexterm significance="preferred"><primary>_XReply</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>_XReply</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>xReply<parameter> *rep</parameter></paramdef>
- <paramdef>int<parameter> extra</parameter></paramdef>
- <paramdef>Bool<parameter> discard</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>rep</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the reply structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>extra</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of 32-bit words expected after the replay.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>discard</emphasis>
- </term>
- <listitem>
- <para>
-Specifies if any data beyond that specified in the extra argument
-should be discarded.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>_XReply</function>
-function waits for a reply packet and copies its contents into the
-specified rep.
-<function>_XReply</function>
-handles error and event packets that occur before the reply is received.
-<function>_XReply</function>
-takes four arguments:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-A
-<type>Display</type>
-* structure
- </para>
- </listitem>
- <listitem>
- <para>
-A pointer to a reply structure (which must be cast to an
-<structname>xReply</structname>
-*)
- </para>
- </listitem>
- <listitem>
- <para>
-The number of additional 32-bit words (beyond
-<function>sizeof( xReply</function>)
-= 32 bytes)
-in the reply structure
- </para>
- </listitem>
- <listitem>
- <para>
-A Boolean that indicates whether
-<function>_XReply</function>
-is to discard any additional bytes
-beyond those it was told to read
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Because most reply structures are 32 bytes long,
-the third argument is usually 0.
-The only core protocol exceptions are the replies to
-<systemitem>GetWindowAttributesl</systemitem>,
-<systemitem>QueryFont</systemitem>,
-<systemitem>QueryKeymap</systemitem>,
-and
-<systemitem>GetKeyboardControl</systemitem>,
-which have longer replies.
-</para>
-<para>
-<!-- .LP -->
-The last argument should be
-<symbol>False</symbol>
-if the reply structure is followed
-by additional variable-length data (such as a list or string).
-It should be
-<symbol>True</symbol>
-if there is not any variable-length data.
-<!-- .NT -->
-This last argument is provided for upward-compatibility reasons
-to allow a client to communicate properly with a hypothetical later
-version of the server that sends more data than the client expected.
-For example, some later version of
-<systemitem>GetWindowAttributesl</systemitem>
-might use a
-larger, but compatible,
-<structname>xGetWindowAttributesReply</structname>
-that contains additional attribute data at the end.
-<!-- .NE -->
-<function>_XReply</function>
-returns
-<symbol>True</symbol>
-if it received a reply successfully or
-<symbol>False</symbol>
-if it received any sort of error.
-</para>
-<para>
-<!-- .LP -->
-For a request with a reply that is not followed by variable-length
-data, you write something like:
-</para>
-<para>
-<!-- .LP -->
-<!-- .R -->
-<programlisting>
-_XReply(display, (xReply *)&amp;rep, 0, True);
-*ret1 = rep.ret1;
-*ret2 = rep.ret2;
-*ret3 = rep.ret3;
-...
-UnlockDisplay(dpy);
-SyncHandle();
-return (rep.ret4);
-}
-</programlisting>
-If there is variable-length data after the reply,
-change the
-<symbol>True</symbol>
-to
-<symbol>False</symbol>,
-and use the appropriate
-<function>_XRead</function>
-function to read the variable-length data.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>_XRead</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *data_return</parameter></paramdef>
- <paramdef>long<parameter> nbytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>data_return</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the buffer.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nbytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes required.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>_XRead</function>
-function reads the specified number of bytes into data_return.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>_XRead16</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>short<parameter> *data_return</parameter></paramdef>
- <paramdef>long<parameter> nbytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>data_return</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the buffer.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nbytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes required.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>_XRead16</function>
-function reads the specified number of bytes,
-unpacking them as 16-bit quantities,
-into the specified array as shorts.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>_XRead32</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>long<parameter> *data_return</parameter></paramdef>
- <paramdef>long<parameter> nbytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>data_return</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the buffer.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nbytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes required.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>_XRead32</function>
-function reads the specified number of bytes,
-unpacking them as 32-bit quantities,
-into the specified array as longs.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>_XRead16Pad</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>short<parameter> *data_return</parameter></paramdef>
- <paramdef>long<parameter> nbytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>data_return</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the buffer.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nbytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes required.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>_XRead16Pad</function>
-function reads the specified number of bytes,
-unpacking them as 16-bit quantities,
-into the specified array as shorts.
-If the number of bytes is not a multiple of four,
-<function>_XRead16Pad</function>
-reads and discards up to two additional pad bytes.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>_XReadPad</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *data_return</parameter></paramdef>
- <paramdef>long<parameter> nbytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>data_return</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the buffer.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nbytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes required.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>_XReadPad</function>
-function reads the specified number of bytes into data_return.
-If the number of bytes is not a multiple of four,
-<function>_XReadPad</function>
-reads and discards up to three additional pad bytes.
-</para>
-<para>
-<!-- .LP -->
-Each protocol request is a little different.
-For further information,
-see the Xlib sources for examples.
-<!-- .SH -->
-Synchronous Calling
-</para>
-<para>
-<!-- .LP -->
-Each procedure should have a call, just before returning to the user,
-to a macro called
-<systemitem>SyncHandle</systemitem>.
-If synchronous mode is enabled (see
-<function>XSynchronize</function>),
-the request is sent immediately.
-The library, however, waits until any error the procedure could generate
-at the server has been handled.
-<!-- .SH -->
-Allocating and Deallocating Memory
-</para>
-<para>
-<!-- .LP -->
-To support the possible reentry of these procedures,
-you must observe several conventions when allocating and deallocating memory,
-most often done when returning data to the user from the window
-system of a size the caller could not know in advance
-(for example, a list of fonts or a list of extensions).
-The standard C library functions on many systems
-are not protected against signals or other multithreaded uses.
-The following analogies to standard I/O library functions
-have been defined:
-</para>
-<para>
-<!-- .LP -->
-These should be used in place of any calls you would make to the normal
-C library functions.
-</para>
-<para>
-<!-- .LP -->
-If you need a single scratch buffer inside a critical section
-(for example, to pack and unpack data to and from the wire protocol),
-the general memory allocators may be too expensive to use
-(particularly in output functions, which are performance critical).
-The following function returns a scratch buffer for use within a
-critical section:
-<indexterm significance="preferred"><primary>_XAllocScratch</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>_XAllocScratch</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>unsignedlong<parameter> nbytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nbytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes required.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-This storage must only be used inside of a critical section of your
-stub. The returned pointer cannot be assumed valid after any call
-that might permit another thread to execute inside Xlib. For example,
-the pointer cannot be assumed valid after any use of the
-<function>GetReq</function>
-or
-<function>Data</function>
-families of macros,
-after any use of
-<function>_XReply</function>,
-or after any use of the
-<function>_XSend</function>
-or
-<function>_XRead</function>
-families of functions.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-The following function returns a scratch buffer for use across
-critical sections:
-<indexterm significance="preferred"><primary>_XAllocTemp</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>_XAllocTemp</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>unsignedlong<parameter> nbytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nbytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes required.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-This storage can be used across calls that might permit another thread to
-execute inside Xlib. The storage must be explicitly returned to Xlib.
-The following function returns the storage:
-<indexterm significance="preferred"><primary>_XFreeTemp</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>_XFreeTemp</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *buf</parameter></paramdef>
- <paramdef>unsignedlong<parameter> nbytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>buf</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the buffer to return.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nbytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the size of the buffer.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-You must pass back the same pointer and size that were returned by
-<function>_XAllocTemp</function>.
-<!-- .SH -->
-Portability Considerations
-</para>
-<para>
-<!-- .LP -->
-Many machine architectures,
-including many of the more recent <acronym>RISC</acronym> architectures,
-do not correctly access data at unaligned locations;
-their compilers pad out structures to preserve this characteristic.
-Many other machines capable of unaligned references pad inside of structures
-as well to preserve alignment, because accessing aligned data is
-usually much faster.
-Because the library and the server use structures to access data at
-arbitrary points in a byte stream,
-all data in request and reply packets <emphasis remap='I'>must</emphasis> be naturally aligned;
-that is, 16-bit data starts on 16-bit boundaries in the request
-and 32-bit data on 32-bit boundaries.
-All requests <emphasis remap='I'>must</emphasis> be a multiple of 32 bits in length to preserve
-the natural alignment in the data stream.
-You must pad structures out to 32-bit boundaries.
-Pad information does not have to be zeroed unless you want to
-preserve such fields for future use in your protocol requests.
-Floating point varies radically between machines and should be
-avoided completely if at all possible.
-</para>
-<para>
-<!-- .LP -->
-This code may run on machines with 16-bit ints.
-So, if any integer argument, variable, or return value either can take
-only nonnegative values or is declared as a
-<type>CARD16</type>
-in the protocol, be sure to declare it as
-<type>unsigned</type>
-<type>int</type>
-and not as
-<type>int</type>.
-(This, of course, does not apply to Booleans or enumerations.)
-</para>
-<para>
-<!-- .LP -->
-Similarly,
-if any integer argument or return value is declared
-<type>CARD32</type>
-in the protocol,
-declare it as an
-<type>unsigned</type>
-<type>long</type>
-and not as
-<type>int</type>
-or
-<type>long</type>.
-This also goes for any internal variables that may
-take on values larger than the maximum 16-bit
-<type>unsigned</type>
-<type>int</type>.
-</para>
-<para>
-<!-- .LP -->
-The library currently assumes that a
-<type>char</type>
-is 8 bits, a
-<type>short</type>
-is 16 bits, an
-<type>int</type>
-is 16 or 32 bits, and a
-<type>long</type>
-is 32 bits.
-The
-<function>PackData</function>
-macro is a half-hearted attempt to deal with the possibility of 32 bit shorts.
-However, much more work is needed to make this work properly.
-<!-- .SH -->
-Deriving the Correct Extension Opcode
-</para>
-<para>
-<!-- .LP -->
-The remaining problem a writer of an extension stub procedure faces that
-the core protocol does not face is to map from the call to the proper
-major and minor opcodes.
-While there are a number of strategies,
-the simplest and fastest is outlined below.
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Declare an array of pointers, _NFILE long (this is normally found
-in
-&lt;stdio.h&gt;
-and is the number of file descriptors supported on the system)
-of type
-<structname>XExtCodes</structname>.
-Make sure these are all initialized to NULL.
- </para>
- </listitem>
- <listitem>
- <para>
-When your stub is entered, your initialization test is just to use
-the display pointer passed in to access the file descriptor and an index
-into the array.
-If the entry is NULL, then this is the first time you
-are entering the procedure for this display.
-Call your initialization procedure and pass to it the display pointer.
- </para>
- </listitem>
- <listitem>
- <para>
-Once in your initialization procedure, call
-<function>XInitExtension</function>;
-if it succeeds, store the pointer returned into this array.
-Make sure to establish a close display handler to allow you to zero the entry.
-Do whatever other initialization your extension requires.
-(For example, install event handlers and so on.)
-Your initialization procedure would normally return a pointer to the
-<structname>XExtCodes</structname>
-structure for this extension, which is what would normally
-be found in your array of pointers.
- </para>
- </listitem>
- <listitem>
- <para>
-After returning from your initialization procedure,
-the stub can now continue normally, because it has its major opcode safely
-in its hand in the
-<structname>XExtCodes</structname>
-structure.
-<!-- .bp -->
- </para>
- </listitem>
-</itemizedlist>
-</appendix>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE appendix PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<appendix id="extensions">
+<title>Extensions</title>
+<para>
+<!-- .XE -->
+Because X can evolve by extensions to the core protocol,
+it is important that extensions not be perceived as second-class citizens.
+At some point,
+your favorite extensions may be adopted as additional parts of the
+X Standard.
+</para>
+<para>
+<!-- .LP -->
+Therefore, there should be little to distinguish the use of an extension from
+that of the core protocol.
+To avoid having to initialize extensions explicitly in application programs,
+it is also important that extensions perform lazy evaluations,
+automatically initializing themselves when called for the first time.
+</para>
+<para>
+<!-- .LP -->
+This appendix describes techniques for writing extensions to Xlib that will
+run at essentially the same performance as the core protocol requests.
+</para>
+<!-- .NT -->
+<note><para>
+It is expected that a given extension to X consists of multiple
+requests.
+Defining 10 new features as 10 separate extensions is a bad practice.
+Rather, they should be packaged into a single extension
+and should use minor opcodes to distinguish the requests.
+</para></note>
+<!-- .NE -->
+<para>
+<!-- .LP -->
+The symbols and macros used for writing stubs to Xlib are listed in
+&lt;X11/Xlibint.h&gt; .
+<!-- .SH -->
+Basic Protocol Support Routines
+</para>
+<para>
+The basic protocol requests for extensions are
+<function>XQueryExtension</function>
+and
+<function>XListExtensions</function>.
+</para>
+<indexterm significance="preferred"><primary>XQueryExtension</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xqueryextension'>
+<funcprototype>
+ <funcdef>Bool <function>XQueryExtension</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *name</parameter></paramdef>
+ <paramdef>int<parameter> *major_opcode_return</parameter></paramdef>
+ <paramdef>int<parameter> *first_event_return</parameter></paramdef>
+ <paramdef>int<parameter> *first_error_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>display</term>
+ <listitem>
+ <para>Specifies the connection to the X server.</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>name</term>
+ <listitem>
+ <para>Specifies the extension name.</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>major_opcode_return</term>
+ <listitem>
+ <para>Returns the major opcode.</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>first_event_return</term>
+ <listitem>
+ <para>Returns the first event code, if any.</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>first_error_return</term>
+ <listitem>
+ <para>Returns the first error code, if any.</para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XQueryExtension</function>
+function determines if the named extension is present.
+If the extension is not present,
+<function>XQueryExtension</function>
+returns
+<symbol>False</symbol>;
+otherwise, it returns
+<symbol>True</symbol>.
+If the extension is present,
+<function>XQueryExtension</function>
+returns the major opcode for the extension to major_opcode_return;
+otherwise,
+it returns zero.
+Any minor opcode and the request formats are specific to the
+extension.
+If the extension involves additional event types,
+<function>XQueryExtension</function>
+returns the base event type code to first_event_return;
+otherwise,
+it returns zero.
+The format of the events is specific to the extension.
+If the extension involves additional error codes,
+<function>XQueryExtension</function>
+returns the base error code to first_error_return;
+otherwise,
+it returns zero.
+The format of additional data in the errors is specific to the extension.
+</para>
+<para>
+<!-- .LP -->
+If the extension name is not in the Host Portable Character Encoding
+the result is implementation-dependent.
+Uppercase and lowercase matter;
+the strings ``thing'', ``Thing'', and ``thinG''
+are all considered different names.
+<indexterm significance="preferred"><primary>XListExtensions</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xlistextensions'>
+<funcprototype>
+ <funcdef>char **<function>XListExtensions</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> *nextensions_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nextensions_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of extensions listed.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XListExtensions</function>
+function returns a list of all extensions supported by the server.
+If the data returned by the server is in the Latin Portable Character Encoding,
+then the returned strings are in the Host Portable Character Encoding.
+Otherwise, the result is implementation-dependent.
+<indexterm significance="preferred"><primary>XFreeExtensionList</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfreeextensionlist'>
+<funcprototype>
+ <funcdef><function>XFreeExtensionList</function></funcdef>
+ <paramdef>char<parameter> **list</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the list of extension names.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreeExtensionList</function>
+function frees the memory allocated by
+<function>XListExtensions</function>.
+<!-- .SH -->
+Hooking into Xlib
+</para>
+<para>
+<!-- .LP -->
+These functions allow you to hook into the library.
+They are not normally used by application programmers but are used
+by people who need to extend the core X protocol and
+the X library interface.
+The functions, which generate protocol requests for X, are typically
+called stubs.
+</para>
+<para>
+<!-- .LP -->
+In extensions, stubs first should check to see if they have initialized
+themselves on a connection.
+If they have not, they then should call
+<function>XInitExtension</function>
+to attempt to initialize themselves on the connection.
+</para>
+<para>
+<!-- .LP -->
+If the extension needs to be informed of GC/font allocation or
+deallocation or if the extension defines new event types,
+the functions described here allow the extension to be
+called when these events occur.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XExtCodes</structname>
+structure returns the information from
+<function>XInitExtension</function>
+and is defined in
+&lt;X11/Xlib.h&gt; :
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XExtCodes</primary></indexterm>
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<synopsis>
+typedef struct _XExtCodes { /* public to extension, cannot be changed */
+ int extension; /* extension number */
+ int major_opcode; /* major op-code assigned by server */
+ int first_event; /* first event number for the extension */
+ int first_error; /* first error number for the extension */
+} XExtCodes;
+</synopsis>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>XInitExtension</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xinitextension'>
+<funcprototype>
+ <funcdef>XExtCodes *<function>XInitExtension</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *name</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XInitExtension</function>
+function determines if the named extension exists.
+Then, it allocates storage for maintaining the
+information about the extension on the connection,
+chains this onto the extension list for the connection,
+and returns the information the stub implementor will need to access
+the extension.
+If the extension does not exist,
+<function>XInitExtension</function>
+returns NULL.
+</para>
+<para>
+<!-- .LP -->
+If the extension name is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+Uppercase and lowercase matter;
+the strings ``thing'', ``Thing'', and ``thinG''
+are all considered different names.
+</para>
+<para>
+<!-- .LP -->
+The extension number in the
+<structname>XExtCodes</structname>
+structure is
+needed in the other calls that follow.
+This extension number is unique only to a single connection.
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XAddExtension</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xaddextension'>
+<funcprototype>
+ <funcdef>XExtCodes *<function>XAddExtension</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+For local Xlib extensions, the
+<function>XAddExtension</function>
+function allocates the
+<structname>XExtCodes</structname>
+structure, bumps the extension number count,
+and chains the extension onto the extension list.
+(This permits extensions to Xlib without requiring server extensions.)
+<!-- .SH -->
+Hooks into the Library
+</para>
+<para>
+<!-- .LP -->
+These functions allow you to define procedures that are to be
+called when various circumstances occur.
+The procedures include the creation of a new GC for a connection,
+the copying of a GC, the freeing of a GC, the creating and freeing of fonts,
+the conversion of events defined by extensions to and from wire
+format, and the handling of errors.
+</para>
+<para>
+<!-- .LP -->
+All of these functions return the previous procedure defined for this
+extension.
+<indexterm significance="preferred"><primary>XESetCloseDisplay</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xesetclosedisplay'>
+<funcprototype>
+ <funcdef>int <function>XESetCloseDisplay</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> extension</parameter></paramdef>
+ <paramdef>int<parameter> (*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>extension</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension number.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when the display is closed.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XESetCloseDisplay</function>
+function defines a procedure to be called whenever
+<function>XCloseDisplay</function>
+is called.
+It returns any previously defined procedure, usually NULL.
+</para>
+<para>
+<!-- .LP -->
+When
+<function>XCloseDisplay</function>
+is called,
+your procedure is called
+with these arguments:
+<funcsynopsis>
+<funcprototype>
+ <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+</para>
+<para>
+<indexterm significance="preferred"><primary>XESetCreateGC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xesetcreategc'>
+<funcprototype>
+ <funcdef>int *<function>XESetCreateGC</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> extension</parameter></paramdef>
+ <paramdef>int<parameter> (*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>extension</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension number.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when a GC is closed.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XESetCreateGC</function>
+function defines a procedure to be called whenever
+a new GC is created.
+It returns any previously defined procedure, usually NULL.
+</para>
+<para>
+<!-- .LP -->
+When a GC is created,
+your procedure is called with these arguments:
+<!-- .LP -->
+<!-- .sM -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>GC <parameter>gc</parameter></paramdef>
+ <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+</para>
+<indexterm significance="preferred"><primary>XESetCopyGC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xesetcopygc'>
+<funcprototype>
+ <funcdef>int *<function>XESetCopyGC</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> extension</parameter></paramdef>
+ <paramdef>int<parameter> (*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>extension</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension number.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when GC components are copied.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XESetCopyGC</function>
+function defines a procedure to be called whenever
+a GC is copied.
+It returns any previously defined procedure, usually NULL.
+</para>
+<para>
+<!-- .LP -->
+When a GC is copied,
+your procedure is called with these arguments:
+<funcsynopsis>
+<funcprototype>
+ <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>GC <parameter>gc</parameter></paramdef>
+ <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+</para>
+<funcsynopsis id='xesetfreegc'>
+<funcprototype>
+ <funcdef>int *<function>XESetFreeGC</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> extension</parameter></paramdef>
+ <paramdef>int<parameter> (*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>extension</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension number.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when a GC is freed.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+The
+<function>XESetFreeGC</function>
+function defines a procedure to be called whenever
+a GC is freed.
+It returns any previously defined procedure, usually NULL.
+</para>
+<para>
+<!-- .LP -->
+When a GC is freed,
+your procedure is called with these arguments:
+<!-- .LP -->
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<!-- .R -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>GC <parameter>gc</parameter></paramdef>
+ <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>XESetCreateFont</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xesetcreatefont'>
+<funcprototype>
+ <funcdef>int *<function>XESetCreateFont</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> extension</parameter></paramdef>
+ <paramdef>int<parameter> (*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>extension</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension number.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when a font is created.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XESetCreateFont</function>
+function defines a procedure to be called whenever
+<function>XLoadQueryFont</function>
+and
+<function>XQueryFont</function>
+are called.
+It returns any previously defined procedure, usually NULL.
+</para>
+<para>
+<!-- .LP -->
+When
+<function>XLoadQueryFont</function>
+or
+<function>XQueryFont</function>
+is called,
+your procedure is called with these arguments:
+<!-- .LP -->
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<!-- .R -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>XFontStruct *<parameter>fs</parameter></paramdef>
+ <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>XESetFreeFont</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xesetfreefont'>
+<funcprototype>
+ <funcdef>int *<function>XESetFreeFont</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> extension</parameter></paramdef>
+ <paramdef>int<parameter> (*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>extension</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension number.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when a font is freed.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XESetFreeFont</function>
+function defines a procedure to be called whenever
+<function>XFreeFont</function>
+is called.
+It returns any previously defined procedure, usually NULL.
+</para>
+<para>
+<!-- .LP -->
+When
+<function>XFreeFont</function>
+is called, your procedure is called with these arguments:
+<!-- .LP -->
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<!-- .R -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>XFontStruct *<parameter>fs</parameter></paramdef>
+ <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XESetWireToEvent</function>
+and
+<function>XESetEventToWire</function>
+functions allow you to define new events to the library.
+An
+<structname>XEvent</structname>
+structure always has a type code (type
+<type>int</type>)
+as the first component.
+This uniquely identifies what kind of event it is.
+The second component is always the serial number (type
+<type>unsigned</type>
+<type>long</type>)
+of the last request processed by the server.
+The third component is always a Boolean (type
+<type>Bool</type>)
+indicating whether the event came from a
+<systemitem>SendEvent</systemitem>
+protocol request.
+The fourth component is always a pointer to the display
+the event was read from.
+The fifth component is always a resource ID of one kind or another,
+usually a window, carefully selected to be useful to toolkit dispatchers.
+The fifth component should always exist, even if
+the event does not have a natural destination;
+if there is no value
+from the protocol to put in this component, initialize it to zero.
+<!-- .NT -->
+There is an implementation limit such that your host event
+structure size cannot be bigger than the size of the
+<structname>XEvent</structname>
+union of structures.
+There also is no way to guarantee that more than 24 elements or 96 characters
+in the structure will be fully portable between machines.
+<!-- .NE -->
+<indexterm significance="preferred"><primary>XESetWireToEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xesetwiretoevent'>
+<funcprototype>
+ <funcdef>int *<function>XESetWireToEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> event_number</parameter></paramdef>
+ <paramdef>Status<parameter> (*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_number</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event code.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when converting an event.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XESetWireToEvent</function>
+function defines a procedure to be called when an event
+needs to be converted from wire format
+(<structname>xEvent</structname>)
+to host format
+(<structname>XEvent</structname>).
+The event number defines which protocol event number to install a
+conversion procedure for.
+<function>XESetWireToEvent</function>
+returns any previously defined procedure.
+<!-- .NT -->
+You can replace a core event conversion function with one
+of your own, although this is not encouraged.
+It would, however, allow you to intercept a core event
+and modify it before being placed in the queue or otherwise examined.
+<!-- .NE -->
+When Xlib needs to convert an event from wire format to host
+format, your procedure is called with these arguments:
+<!-- .LP -->
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<!-- .R -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>XEvent *<parameter>re</parameter></paramdef>
+ <paramdef>xEvent *<parameter>event</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .LP -->
+<!-- .eM -->
+Your procedure must return status to indicate if the conversion succeeded.
+The re argument is a pointer to where the host format event should be stored,
+and the event argument is the 32-byte wire event structure.
+In the
+<structname>XEvent</structname>
+structure you are creating,
+you must fill in the five required members of the event structure.
+You should fill in the type member with the type specified for the
+<structname>xEvent</structname>
+structure.
+You should copy all other members from the
+<structname>xEvent</structname>
+structure (wire format) to the
+<structname>XEvent</structname>
+structure (host format).
+Your conversion procedure should return
+<symbol>True</symbol>
+if the event should be placed in the queue or
+<symbol>False</symbol>
+if it should not be placed in the queue.
+</para>
+<para>
+<!-- .LP -->
+To initialize the serial number component of the event, call
+<function>_XSetLastRequestRead</function>
+with the event and use the return value.
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>_XSetLastRequestRead</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetlastrequestread'>
+<funcprototype>
+ <funcdef>unsigned long<function>_XSetLastRequestRead</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>xGenericReply<parameter> *rep</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rep</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the wire event structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>_XSetLastRequestRead</function>
+function computes and returns a complete serial number from the partial
+serial number in the event.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XESetEventToWire</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xeseteventtowire'>
+<funcprototype>
+ <funcdef>Status *<function>XESetEventToWire</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> event_number</parameter></paramdef>
+ <paramdef>int<parameter> (*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_number</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event code.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when converting an event.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XESetEventToWire</function>
+function defines a procedure to be called when an event
+needs to be converted from host format
+(<structname>XEvent</structname>)
+to wire format
+(<structname>xEvent</structname>)
+form.
+The event number defines which protocol event number to install a
+conversion procedure for.
+<function>XESetEventToWire</function>
+returns any previously defined procedure.
+It returns zero if the conversion fails or nonzero otherwise.
+<!-- .NT -->
+You can replace a core event conversion function with one
+of your own, although this is not encouraged.
+It would, however, allow you to intercept a core event
+and modify it before being sent to another client.
+<!-- .NE -->
+When Xlib needs to convert an event from host format to wire format,
+your procedure is called with these arguments:
+<!-- .LP -->
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<!-- .R -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>XEvent *<parameter>re</parameter></paramdef>
+ <paramdef>xEvent *<parameter>event</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .LP -->
+<!-- .eM -->
+The re argument is a pointer to the host format event,
+and the event argument is a pointer to where the 32-byte wire event
+structure should be stored.
+You should fill in the type with the type from the
+<structname>XEvent</structname>
+structure.
+All other members then should be copied from the host format to the
+<structname>xEvent</structname>
+structure.
+<indexterm significance="preferred"><primary>XESetWireToError</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xesetwiretoerror'>
+<funcprototype>
+ <funcdef>Bool *<function>XESetWireToError</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> error_number</parameter></paramdef>
+ <paramdef>Bool<parameter> (*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>error_number</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the error code.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when an error is received.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XESetWireToError</function>
+function defines a procedure to be called when an extension
+error needs to be converted from wire format to host format.
+The error number defines which protocol error code to install
+the conversion procedure for.
+<function>XESetWireToError</function>
+returns any previously defined procedure.
+</para>
+<para>
+<!-- .LP -->
+Use this function for extension errors that contain additional error values
+beyond those in a core X error, when multiple wire errors must be combined
+into a single Xlib error, or when it is necessary to intercept an
+X error before it is otherwise examined.
+</para>
+<para>
+<!-- .LP -->
+When Xlib needs to convert an error from wire format to host format,
+the procedure is called with these arguments:
+<!-- .LP -->
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<!-- .R -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>XErrorEvent *<parameter>he</parameter></paramdef>
+ <paramdef>xError *<parameter>we</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .LP -->
+<!-- .eM -->
+The he argument is a pointer to where the host format error should be stored.
+The structure pointed at by he is guaranteed to be as large as an
+<structname>XEvent</structname>
+structure and so can be cast to a type larger than an
+<structname>XErrorEvent</structname>
+to store additional values.
+If the error is to be completely ignored by Xlib
+(for example, several protocol error structures will be combined into
+one Xlib error),
+then the function should return
+<symbol>False</symbol>;
+otherwise, it should return
+<symbol>True</symbol>.
+<indexterm significance="preferred"><primary>XESetError</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xeseterror'>
+<funcprototype>
+ <funcdef>int *<function>XESetError</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> extension</parameter></paramdef>
+ <paramdef>int<parameter> (*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>extension</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension number.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when an error is received.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Inside Xlib, there are times that you may want to suppress the
+calling of the external error handling when an error occurs.
+This allows status to be returned on a call at the cost of the call
+being synchronous (though most such functions are query operations, in any
+case, and are typically programmed to be synchronous).
+</para>
+<para>
+<!-- .LP -->
+When Xlib detects a protocol error in
+<function>_XReply</function>,
+it calls your procedure with these arguments:
+<!-- .LP -->
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<!-- .R -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>xError *<parameter>err</parameter></paramdef>
+ <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
+ <paramdef>int *<parameter>ret_code</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .LP -->
+<!-- .eM -->
+The err argument is a pointer to the 32-byte wire format error.
+The codes argument is a pointer to the extension codes structure.
+The ret_code argument is the return code you may want
+<function>_XReply</function>
+returned to.
+</para>
+<para>
+<!-- .LP -->
+If your procedure returns a zero value,
+the error is not suppressed, and
+the client's error handler is called.
+(For further information, see section 11.8.2.)
+If your procedure returns nonzero,
+the error is suppressed, and
+<function>_XReply</function>
+returns the value of ret_code.
+<indexterm significance="preferred"><primary>XESetErrorString</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xeseterrorstring'>
+<funcprototype>
+ <funcdef>char *<function>XESetErrorString</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> extension</parameter></paramdef>
+ <paramdef>char<parameter> *(*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>extension</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension number.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call to obtain an error string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetErrorText</function>
+function returns a string to the user for an error.
+<function>XESetErrorString</function>
+allows you to define a procedure to be called that
+should return a pointer to the error message.
+The following is an example.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<!-- .R -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>int <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>int <parameter>code</parameter></paramdef>
+ <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
+ <paramdef>char *<parameter>buffer</parameter></paramdef>
+ <paramdef>int <parameter>nbytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .LP -->
+<!-- .eM -->
+Your procedure is called with the error code for every error detected.
+You should copy nbytes of a null-terminated string containing the
+error message into buffer.
+<indexterm significance="preferred"><primary>XESetPrintErrorValues</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xesetprinterrorvalues'>
+<funcprototype>
+ <funcdef>void *<function>XESetPrintErrorValues</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> extension</parameter></paramdef>
+ <paramdef>void<parameter> (*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>extension</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension number.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when an error is printed.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XESetPrintErrorValues</function>
+function defines a procedure to be called when an extension
+error is printed, to print the error values.
+Use this function for extension errors that contain additional error values
+beyond those in a core X error.
+It returns any previously defined procedure.
+</para>
+<para>
+<!-- .LP -->
+When Xlib needs to print an error,
+the procedure is called with these arguments:
+<!-- .LP -->
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<!-- .R -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>void <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>XErrorEvent *<parameter>ev</parameter></paramdef>
+ <paramdef>void *<parameter>fp</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .LP -->
+<!-- .eM -->
+The structure pointed at by ev is guaranteed to be as large as an
+<structname>XEvent</structname>
+structure and so can be cast to a type larger than an
+<structname>XErrorEvent</structname>
+to obtain additional values set by using
+<function>XESetWireToError</function>.
+The underlying type of the fp argument is system dependent;
+on a <acronym>POSIX</acronym>-compliant system, fp should be cast to type FILE*.
+<indexterm significance="preferred"><primary>XESetFlushGC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xesetflushgc'>
+<funcprototype>
+ <funcdef>int *<function>XESetFlushGC</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> extension</parameter></paramdef>
+ <paramdef>int<parameter> *(*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>extension</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension number.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when a GC is flushed.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The procedure set by the
+<function>XESetFlushGC</function>
+function has the same interface as the procedure set by the
+<function>XESetCopyGC</function>
+function, but is called when a GC cache needs to be updated in the server.
+<indexterm significance="preferred"><primary>XESetBeforeFlush</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>int *<function>XESetCopyGC</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> extension</parameter></paramdef>
+ <paramdef>int<parameter> *(*proc)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>extension</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension number.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to call when a buffer is flushed.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XESetBeforeFlush</function>
+function defines a procedure to be called when data is about to be
+sent to the server. When data is about to be sent, your procedure is
+called one or more times with these arguments:
+<!-- .LP -->
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<!-- .R -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>void <function>(*<replaceable>proc</replaceable>)</function></funcdef>
+ <paramdef>Display *<parameter>display</parameter></paramdef>
+ <paramdef>XExtCodes *<parameter>codes</parameter></paramdef>
+ <paramdef>char *<parameter>data</parameter></paramdef>
+ <paramdef>long <parameter>len</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .LP -->
+<!-- .eM -->
+The data argument specifies a portion of the outgoing data buffer,
+and its length in bytes is specified by the len argument.
+Your procedure must not alter the contents of the data and must not
+do additional protocol requests to the same display.
+<!-- .SH -->
+Hooks onto Xlib Data Structures
+</para>
+<para>
+<!-- .LP -->
+Various Xlib data structures have provisions for extension procedures
+to chain extension supplied data onto a list.
+These structures are
+<structname>GC</structname>,
+<structname>Visual</structname>,
+<type>Screen</type>,
+<structname>ScreenFormat</structname>,
+<type>Display</type>,
+and
+<structname>XFontStruct</structname>.
+Because the list pointer is always the first member in the structure,
+a single set of procedures can be used to manipulate the data
+on these lists.
+</para>
+<para>
+<!-- .LP -->
+The following structure is used in the functions in this section
+and is defined in
+&lt;X11/Xlib.h&gt;
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XExtData</primary></indexterm>
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<synopsis>
+typedef struct _XExtData {
+ int number; /* number returned by XInitExtension */
+ struct _XExtData *next; /* next item on list of data for structure */
+ int (*free_private)(); /* if defined, called to free private */
+ XPointer private_data; /* data private to this extension. */
+} XExtData;
+</synopsis>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+When any of the data structures listed above are freed,
+the list is walked, and the structure's free procedure (if any) is called.
+If free is NULL,
+then the library frees both the data pointed to by the private_data member
+and the structure itself.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<!-- .TA .5i -->
+<!-- .ta .5i -->
+<synopsis>
+union { Display *display;
+ GC gc;
+ Visual *visual;
+ Screen *screen;
+ ScreenFormat *pixmap_format;
+ XFontStruct *font } XEDataObject;
+</synopsis>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>XEHeadOfExtensionList</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xeheadofextensionlist'>
+<funcprototype>
+ <funcdef>XExtData **<function>XEHeadOfExtensionList</function></funcdef>
+ <paramdef>XEDataObject<parameter> object</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>object</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the object.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XEHeadOfExtensionList</function>
+function returns a pointer to the list of extension structures attached
+to the specified object.
+In concert with
+<function>XAddToExtensionList</function>,
+<function>XEHeadOfExtensionList</function>
+allows an extension to attach arbitrary data to any of the structures
+of types contained in
+<structname>XEDataObject</structname>.
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XAddToExtensionList</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xaddtoextensionlist'>
+<funcprototype>
+ <funcdef><function>XAddToExtensionList</function></funcdef>
+ <paramdef>XExtData<parameter> **structure</parameter></paramdef>
+ <paramdef>XExtData<parameter> *ext_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>structure</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ext_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension data structure to add.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The structure argument is a pointer to one of the data structures
+enumerated above.
+You must initialize ext_data-&gt;number with the extension number
+before calling this function.
+<indexterm significance="preferred"><primary>XFindOnExtensionList</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfindonextensionlist'>
+<funcprototype>
+ <funcdef>XExtData *<function>XFindOnExtensionList</function></funcdef>
+ <paramdef>struct_XExtData<parameter> **structure</parameter></paramdef>
+ <paramdef>int<parameter> number</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>structure</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>number</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the extension number from
+<function>XInitExtension</function>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFindOnExtensionList</function>
+function returns the first extension data structure
+for the extension numbered number.
+It is expected that an extension will add at most one extension
+data structure to any single data structure's extension data list.
+There is no way to find additional structures.
+</para>
+<para>
+<!-- .LP -->
+The
+<function>XAllocID</function>
+macro, which allocates and returns a resource ID, is defined in
+&lt;X11/Xlib.h&gt;.
+<indexterm significance="preferred"><primary>XAllocID</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xallocid'>
+<funcprototype>
+ <funcdef><function>XAllocID</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+This macro is a call through the
+<type>Display</type>
+structure to an internal resource ID allocator.
+It returns a resource ID that you can use when creating new resources.
+</para>
+<para>
+<!-- .LP -->
+The
+<function>XAllocIDs</function>
+macro allocates and returns an array of resource ID.
+<indexterm significance="preferred"><primary>XAllocIDs</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xallocids'>
+<funcprototype>
+ <funcdef><function>XAllocIDs</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XID<parameter> *ids_return</parameter></paramdef>
+ <paramdef>int<parameter> count</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ids_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the resource IDs.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rep</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of resource IDs requested.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+This macro is a call through the
+<type>Display</type>
+structure to an internal resource ID allocator.
+It returns resource IDs to the array supplied by the caller.
+To correctly handle automatic reuse of resource IDs, you must call
+<function>XAllocIDs</function>
+when requesting multiple resource IDs. This call might generate
+protocol requests.
+<!-- .SH -->
+GC Caching
+</para>
+<para>
+<!-- .LP -->
+GCs are cached by the library to allow merging of independent change
+requests to the same GC into single protocol requests.
+This is typically called a write-back cache.
+Any extension procedure whose behavior depends on the contents of a GC
+must flush the GC cache to make sure the server has up-to-date contents
+in its GC.
+</para>
+<para>
+<!-- .LP -->
+The
+<function>FlushGC</function>
+macro checks the dirty bits in the library's GC structure and calls
+<function>_XFlushGCCache</function>
+if any elements have changed.
+The
+<function>FlushGC</function>
+macro is defined as follows:
+<indexterm significance="preferred"><primary>FlushGC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='flushgc'>
+<funcprototype>
+ <funcdef><function>FlushGC</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Note that if you extend the GC to add additional resource ID components,
+you should ensure that the library stub sends the change request immediately.
+This is because a client can free a resource immediately after
+using it, so if you only stored the value in the cache without
+forcing a protocol request, the resource might be destroyed before being
+set into the GC.
+You can use the
+<function>_XFlushGCCache</function>
+procedure
+to force the cache to be flushed.
+The
+<function>_XFlushGCCache</function>
+procedure
+is defined as follows:
+<indexterm significance="preferred"><primary>_XFlushGCCache</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='_xflushgccache'>
+<funcprototype>
+ <funcdef><function>_XFlushGCCache</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .SH -->
+Graphics Batching
+</para>
+<para>
+<!-- .LP -->
+If you extend X to add more poly graphics primitives, you may be able to
+take advantage of facilities in the library to allow back-to-back
+single calls to be transformed into poly requests.
+This may dramatically improve performance of programs that are not
+written using poly requests.
+A pointer to an
+<structname>xReq</structname>,
+called last_req in the display structure, is the last request being processed.
+By checking that the last request
+type, drawable, gc, and other options are the same as the new one
+and that there is enough space left in the buffer, you may be able
+to just extend the previous graphics request by extending the length
+field of the request and appending the data to the buffer.
+This can improve performance by five times or more in naive programs.
+For example, here is the source for the
+<function>XDrawPoint</function>
+stub.
+(Writing extension stubs is discussed in the next section.)
+</para>
+<!-- .sM -->
+<!-- .nf -->
+<programlisting>
+#include &lt;X11/Xlibint.h&gt;
+
+/* precompute the maximum size of batching request allowed */
+
+static int size = sizeof(xPolyPointReq) + EPERBATCH * sizeof(xPoint);
+
+XDrawPoint(dpy, d, gc, x, y)
+ register Display *dpy;
+ Drawable d;
+ GC gc;
+ int x, y; /* INT16 */
+{
+ xPoint *point;
+ LockDisplay(dpy);
+ FlushGC(dpy, gc);
+ {
+ register xPolyPointReq *req = (xPolyPointReq *) dpy-&gt;last_req;
+ /* if same as previous request, with same drawable, batch requests */
+ if (
+ (req-&gt;reqType == X_PolyPoint)
+ &amp;&amp; (req-&gt;drawable == d)
+ &amp;&amp; (req-&gt;gc == gc-&gt;gid)
+ &amp;&amp; (req-&gt;coordMode == CoordModeOrigin)
+ &amp;&amp; ((dpy-&gt;bufptr + sizeof (xPoint)) &lt;= dpy-&gt;bufmax)
+ &amp;&amp; (((char *)dpy-&gt;bufptr - (char *)req) &lt; size) ) {
+ point = (xPoint *) dpy-&gt;bufptr;
+ req-&gt;length += sizeof (xPoint) &gt;&gt; 2;
+ dpy-&gt;bufptr += sizeof (xPoint);
+ }
+
+ else {
+ GetReqExtra(PolyPoint, 4, req); /* 1 point = 4 bytes */
+ req-&gt;drawable = d;
+ req-&gt;gc = gc-&gt;gid;
+ req-&gt;coordMode = CoordModeOrigin;
+ point = (xPoint *) (req + 1);
+ }
+ point-&gt;x = x;
+ point-&gt;y = y;
+ }
+ UnlockDisplay(dpy);
+ SyncHandle();
+}
+</programlisting>
+<!-- .fi -->
+<para>
+<!-- .LP -->
+<!-- .eM -->
+To keep clients from generating very long requests that may monopolize the
+server,
+there is a symbol defined in
+&lt;X11/Xlibint.h&gt;
+of EPERBATCH on the number of requests batched.
+Most of the performance benefit occurs in the first few merged requests.
+Note that
+<function>FlushGC</function>
+is called <emphasis remap='I'>before</emphasis> picking up the value of last_req,
+because it may modify this field.
+<!-- .SH -->
+Writing Extension Stubs
+</para>
+<para>
+<!-- .LP -->
+All X requests always contain the length of the request,
+expressed as a 16-bit quantity of 32 bits.
+This means that a single request can be no more than 256K bytes in
+length.
+Some servers may not support single requests of such a length.
+The value of dpy-&gt;max_request_size contains the maximum length as
+defined by the server implementation.
+For further information,
+see ``X Window System Protocol.''
+<!-- .SH -->
+Requests, Replies, and Xproto.h
+</para>
+<para>
+<!-- .LP -->
+The
+&lt;X11/Xproto.h&gt;
+file contains three sets of definitions that
+are of interest to the stub implementor:
+request names, request structures, and reply structures.
+</para>
+<para>
+<!-- .LP -->
+You need to generate a file equivalent to
+&lt;X11/Xproto.h&gt;
+for your extension and need to include it in your stub procedure.
+Each stub procedure also must include
+&lt;X11/Xlibint.h&gt; .
+</para>
+<para>
+<!-- .LP -->
+The identifiers are deliberately chosen in such a way that, if the
+request is called X_DoSomething, then its request structure is
+xDoSomethingReq, and its reply is xDoSomethingReply.
+The GetReq family of macros, defined in
+&lt;X11/Xlibint.h&gt; ,
+takes advantage of this naming scheme.
+</para>
+<para>
+<!-- .LP -->
+For each X request,
+there is a definition in
+&lt;X11/Xproto.h&gt;
+that looks similar to this:
+</para>
+<para>
+<!-- .LP -->
+<!-- .R -->
+<programlisting>
+#define X_DoSomething 42
+</programlisting>
+In your extension header file,
+this will be a minor opcode,
+instead of a major opcode.
+<!-- .SH -->
+Request Format
+</para>
+<para>
+<!-- .LP -->
+Every request contains an 8-bit major opcode and a 16-bit length field
+expressed in units of 4 bytes.
+Every request consists of 4 bytes of header
+(containing the major opcode, the length field, and a data byte) followed by
+zero or more additional bytes of data.
+The length field defines the total length of the request, including the header.
+The length field in a request must equal the minimum length required to contain
+the request.
+If the specified length is smaller or larger than the required length,
+the server should generate a
+<errorname>BadLength</errorname>
+error.
+Unused bytes in a request are not required to be zero.
+Extensions should be designed in such a way that long protocol requests
+can be split up into smaller requests,
+if it is possible to exceed the maximum request size of the server.
+The protocol guarantees the maximum request size to be no smaller than
+4096 units (16384 bytes).
+</para>
+<para>
+<!-- .LP -->
+Major opcodes 128 through 255 are reserved for extensions.
+Extensions are intended to contain multiple requests,
+so extension requests typically have an additional minor opcode encoded
+in the second data byte in the request header,
+but the placement and interpretation of this minor opcode as well as all
+other fields in extension requests are not defined by the core protocol.
+Every request is implicitly assigned a sequence number (starting with one)
+used in replies, errors, and events.
+</para>
+<para>
+<!-- .LP -->
+To help but not cure portability problems to certain machines, the
+<symbol>B16</symbol>
+and
+<symbol>B32</symbol>
+macros have been defined so that they can become bitfield specifications
+on some machines.
+For example, on a Cray,
+these should be used for all 16-bit and 32-bit quantities, as discussed below.
+</para>
+<para>
+<!-- .LP -->
+Most protocol requests have a corresponding structure typedef in
+&lt;X11/Xproto.h&gt;,
+which looks like:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>xDoSomethingReq</primary></indexterm>
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<synopsis>
+typedef struct _DoSomethingReq {
+ CARD8 reqType; /* X_DoSomething */
+ CARD8 someDatum; /* used differently in different requests */
+ CARD16 length B16; /* total # of bytes in request, divided by 4 */
+ ...
+ /* request-specific data */
+ ...
+} xDoSomethingReq;
+</synopsis>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If a core protocol request has a single 32-bit argument,
+you need not declare a request structure in your extension header file.
+Instead, such requests use the
+<structname>xResourceReq</structname>
+structure in
+&lt;X11/Xproto.h&gt;.
+This structure is used for any request whose single argument is a
+<type>Window</type>,
+<type>Pixmap</type>,
+<type>Drawable</type>,
+<type>GContext</type>,
+<type>Font</type>,
+<type>Cursor</type>,
+<type>Colormap</type>,
+<type>Atom</type>,
+or
+<type>VisualID</type>.
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>xResourceReq</primary></indexterm>
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<synopsis>
+typedef struct _ResourceReq {
+ CARD8 reqType; /* the request type, e.g. X_DoSomething */
+ BYTE pad; /* not used */
+ CARD16 length B16; /* 2 (= total # of bytes in request, divided by 4) */
+ CARD32 id B32; /* the Window, Drawable, Font, GContext, etc. */
+} xResourceReq;
+</synopsis>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If convenient,
+you can do something similar in your extension header file.
+</para>
+<para>
+<!-- .LP -->
+In both of these structures,
+the reqType field identifies the type of the request (for example,
+X_MapWindow or X_CreatePixmap).
+The length field tells how long the request is
+in units of 4-byte longwords.
+This length includes both the request structure itself and any
+variable-length data, such as strings or lists, that follow the
+request structure.
+Request structures come in different sizes,
+but all requests are padded to be multiples of four bytes long.
+</para>
+<para>
+<!-- .LP -->
+A few protocol requests take no arguments at all.
+Instead, they use the
+<structname>xReq</structname>
+structure in
+&lt;X11/Xproto.h&gt;,
+which contains only a reqType and a length (and a pad byte).
+</para>
+<para>
+<!-- .LP -->
+If the protocol request requires a reply,
+then
+&lt;X11/Xproto.h&gt;
+also contains a reply structure typedef:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>xDoSomethingReply</primary></indexterm>
+<!-- .sM -->
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+<synopsis>
+typedef struct _DoSomethingReply {
+ BYTE type; /* always X_Reply */
+ BYTE someDatum; /* used differently in different requests */
+ CARD16 sequenceNumber B16; /* # of requests sent so far */
+ CARD32 length B32; /* # of additional bytes, divided by 4 */
+ ...
+ /* request-specific data */
+ ...
+} xDoSomethingReply;
+</synopsis>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Most of these reply structures are 32 bytes long.
+If there are not that many reply values,
+then they contain a sufficient number of pad fields
+to bring them up to 32 bytes.
+The length field is the total number of bytes in the request minus 32,
+divided by 4.
+This length will be nonzero only if:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The reply structure is followed by variable-length data,
+such as a list or string.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The reply structure is longer than 32 bytes.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Only
+<systemitem>GetWindowAttributesl</systemitem>,
+<systemitem>QueryFont</systemitem>,
+<systemitem>QueryKeymap</systemitem>,
+and
+<systemitem>GetKeyboardControl</systemitem>
+have reply structures longer than 32 bytes in the core protocol.
+</para>
+<para>
+<!-- .LP -->
+A few protocol requests return replies that contain no data.
+&lt;X11/Xproto.h&gt;
+does not define reply structures for these.
+Instead, they use the
+<structname>xGenericReply</structname>
+structure, which contains only a type, length,
+and sequence number (and sufficient padding to make it 32 bytes long).
+<!-- .SH -->
+Starting to Write a Stub Procedure
+</para>
+<para>
+<!-- .LP -->
+An Xlib stub procedure should start like this:
+</para>
+<para>
+<!-- .LP -->
+<!-- .R -->
+<programlisting>
+#include "&lt;X11/Xlibint.h&gt;
+
+XDoSomething (arguments, ... )
+/* argument declarations */
+{
+
+register XDoSomethingReq *req;
+...
+</programlisting>
+If the protocol request has a reply,
+then the variable declarations should include the reply structure for the request.
+The following is an example:
+</para>
+<para>
+<!-- .LP -->
+<!-- .R -->
+<programlisting>
+xDoSomethingReply rep;
+</programlisting>
+<!-- .SH -->
+Locking Data Structures
+</para>
+<para>
+<!-- .LP -->
+To lock the display structure for systems that
+want to support multithreaded access to a single display connection,
+each stub will need to lock its critical section.
+Generally, this section is the point from just before the appropriate GetReq
+call until all arguments to the call have been stored into the buffer.
+The precise instructions needed for this locking depend upon the machine
+architecture.
+Two calls, which are generally implemented as macros, have been provided.
+<indexterm significance="preferred"><primary>LockDisplay</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='lockdisplay'>
+<funcprototype>
+ <funcdef><function>LockDisplay</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>UnlockDisplay</primary></indexterm>
+<funcsynopsis id='unlockdisplay'>
+<funcprototype>
+ <funcdef><function>UnlockDisplay</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .SH -->
+Sending the Protocol Request and Arguments
+</para>
+<para>
+<!-- .LP -->
+After the variable declarations,
+a stub procedure should call one of four macros defined in
+&lt;X11/Xlibint.h&gt;:
+<function>GetReq</function>,
+<function>GetReqExtra</function>,
+<function>GetResReq</function>,
+or
+<function>GetEmptyReq</function>.
+All of these macros take, as their first argument,
+the name of the protocol request as declared in
+&lt;X11/Xproto.h&gt;
+except with X_ removed.
+Each one declares a
+<type>Display</type>
+structure pointer,
+called dpy, and a pointer to a request structure, called req,
+which is of the appropriate type.
+The macro then appends the request structure to the output buffer,
+fills in its type and length field, and sets req to point to it.
+</para>
+<para>
+<!-- .LP -->
+If the protocol request has no arguments (for instance, X_GrabServer),
+then use
+<function>GetEmptyReq</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .R -->
+<programlisting>
+GetEmptyReq (DoSomething, req);
+</programlisting>
+If the protocol request has a single 32-bit argument (such as a
+<type>Pixmap</type>,
+<type>Window</type>,
+<type>Drawable</type>,
+<type>Atom</type>,
+and so on),
+then use
+<function>GetResReq</function>.
+The second argument to the macro is the 32-bit object.
+<symbol>X_MapWindow</symbol>
+is a good example.
+</para>
+<para>
+<!-- .LP -->
+<!-- .R -->
+<programlisting>
+GetResReq (DoSomething, rid, req);
+</programlisting>
+The rid argument is the
+<type>Pixmap</type>,
+<type>Window</type>,
+or other resource ID.
+</para>
+<para>
+<!-- .LP -->
+If the protocol request takes any other argument list,
+then call
+<function>GetReq</function>.
+After the
+<function>GetReq</function>,
+you need to set all the other fields in the request structure,
+usually from arguments to the stub procedure.
+</para>
+<para>
+<!-- .LP -->
+<!-- .R -->
+<programlisting>
+GetReq (DoSomething, req);
+/* fill in arguments here */
+req-&gt;arg1 = arg1;
+req-&gt;arg2 = arg2;
+...
+</programlisting>
+A few stub procedures (such as
+<function>XCreateGC</function>
+and
+<function>XCreatePixmap</function>)
+return a resource ID to the caller but pass a resource ID as an argument
+to the protocol request.
+Such procedures use the macro
+<function>XAllocID</function>
+to allocate a resource ID from the range of IDs
+that were assigned to this client when it opened the connection.
+</para>
+<para>
+<!-- .LP -->
+<!-- .R -->
+<programlisting>
+rid = req-&gt;rid = XAllocID();
+...
+return (rid);
+</programlisting>
+Finally, some stub procedures transmit a fixed amount of variable-length
+data after the request.
+Typically, these procedures (such as
+<function>XMoveWindow</function>
+and
+<function>XSetBackground</function>)
+are special cases of more general functions like
+<function>XMoveResizeWindow</function>
+and
+<function>XChangeGC</function>.
+These procedures use
+<function>GetReqExtra</function>,
+which is the same as
+<function>GetReq</function>
+except that it takes an additional argument (the number of
+extra bytes to allocate in the output buffer after the request structure).
+This number should always be a multiple of four.
+<!-- .SH -->
+Variable Length Arguments
+</para>
+<para>
+<!-- .LP -->
+Some protocol requests take additional variable-length data that
+follow the
+<type>xDoSomethingReq</type>
+structure.
+The format of this data varies from request to request.
+Some requests require a sequence of 8-bit bytes,
+others a sequence of 16-bit or 32-bit entities,
+and still others a sequence of structures.
+</para>
+<para>
+<!-- .LP -->
+It is necessary to add the length of any variable-length data to the
+length field of the request structure.
+That length field is in units of 32-bit longwords.
+If the data is a string or other sequence of 8-bit bytes,
+then you must round the length up and shift it before adding:
+</para>
+<para>
+<!-- .LP -->
+<!-- .R -->
+<programlisting>
+req-&gt;length += (nbytes+3)&gt;&gt;2;
+</programlisting>
+To transmit variable-length data, use the
+<function>Data</function>
+macros.
+If the data fits into the output buffer,
+then this macro copies it to the buffer.
+If it does not fit, however,
+the
+<function>Data</function>
+macro calls
+<function>_XSend</function>,
+which transmits first the contents of the buffer and then your data.
+The
+<function>Data</function>
+macros take three arguments:
+the display, a pointer to the beginning of the data,
+and the number of bytes to be sent.
+<!-- .sM -->
+<funcsynopsis id='data'>
+<funcprototype>
+ <funcdef><function>Data</function></funcdef>
+ <paramdef><parameter> display</parameter></paramdef>
+ <paramdef>(char<parameter> *</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>Data</function>,
+<function>Data16</function>,
+and
+<function>Data32</function>
+are macros that may use their last argument
+more than once, so that argument should be a variable rather than
+an expression such as ``nitems*sizeof(item)''.
+You should do that kind of computation in a separate statement before calling
+them.
+Use the appropriate macro when sending byte, short, or long data.
+</para>
+<para>
+<!-- .LP -->
+If the protocol request requires a reply,
+then call the procedure
+<function>_XSend</function>
+instead of the
+<function>Data</function>
+macro.
+<function>_XSend</function>
+takes the same arguments, but because it sends your data immediately instead of
+copying it into the output buffer (which would later be flushed
+anyway by the following call on
+<function>_XReply</function>),
+it is faster.
+<!-- .SH -->
+Replies
+</para>
+<para>
+<!-- .LP -->
+If the protocol request has a reply,
+then call
+<function>_XReply</function>
+after you have finished dealing with
+all the fixed-length and variable-length arguments.
+<function>_XReply</function>
+flushes the output buffer and waits for an
+<structname>xReply</structname>
+packet to arrive.
+If any events arrive in the meantime,
+<function>_XReply</function>
+places them in the queue for later use.
+<indexterm significance="preferred"><primary>_XReply</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='_xreply'>
+<funcprototype>
+ <funcdef>Status <function>_XReply</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>xReply<parameter> *rep</parameter></paramdef>
+ <paramdef>int<parameter> extra</parameter></paramdef>
+ <paramdef>Bool<parameter> discard</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rep</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the reply structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>extra</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of 32-bit words expected after the replay.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>discard</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies if any data beyond that specified in the extra argument
+should be discarded.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>_XReply</function>
+function waits for a reply packet and copies its contents into the
+specified rep.
+<function>_XReply</function>
+handles error and event packets that occur before the reply is received.
+<function>_XReply</function>
+takes four arguments:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+A
+<type>Display</type>
+* structure
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A pointer to a reply structure (which must be cast to an
+<structname>xReply</structname>
+*)
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The number of additional 32-bit words (beyond
+<function>sizeof( xReply</function>)
+= 32 bytes)
+in the reply structure
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A Boolean that indicates whether
+<function>_XReply</function>
+is to discard any additional bytes
+beyond those it was told to read
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Because most reply structures are 32 bytes long,
+the third argument is usually 0.
+The only core protocol exceptions are the replies to
+<systemitem>GetWindowAttributesl</systemitem>,
+<systemitem>QueryFont</systemitem>,
+<systemitem>QueryKeymap</systemitem>,
+and
+<systemitem>GetKeyboardControl</systemitem>,
+which have longer replies.
+</para>
+<para>
+<!-- .LP -->
+The last argument should be
+<symbol>False</symbol>
+if the reply structure is followed
+by additional variable-length data (such as a list or string).
+It should be
+<symbol>True</symbol>
+if there is not any variable-length data.
+<!-- .NT -->
+This last argument is provided for upward-compatibility reasons
+to allow a client to communicate properly with a hypothetical later
+version of the server that sends more data than the client expected.
+For example, some later version of
+<systemitem>GetWindowAttributesl</systemitem>
+might use a
+larger, but compatible,
+<structname>xGetWindowAttributesReply</structname>
+that contains additional attribute data at the end.
+<!-- .NE -->
+<function>_XReply</function>
+returns
+<symbol>True</symbol>
+if it received a reply successfully or
+<symbol>False</symbol>
+if it received any sort of error.
+</para>
+<para>
+<!-- .LP -->
+For a request with a reply that is not followed by variable-length
+data, you write something like:
+</para>
+<para>
+<!-- .LP -->
+<!-- .R -->
+<programlisting>
+_XReply(display, (xReply *)&amp;rep, 0, True);
+*ret1 = rep.ret1;
+*ret2 = rep.ret2;
+*ret3 = rep.ret3;
+...
+UnlockDisplay(dpy);
+SyncHandle();
+return (rep.ret4);
+}
+</programlisting>
+If there is variable-length data after the reply,
+change the
+<symbol>True</symbol>
+to
+<symbol>False</symbol>,
+and use the appropriate
+<function>_XRead</function>
+function to read the variable-length data.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<funcsynopsis id='_xread'>
+<funcprototype>
+ <funcdef><function>_XRead</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *data_return</parameter></paramdef>
+ <paramdef>long<parameter> nbytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the buffer.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nbytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes required.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>_XRead</function>
+function reads the specified number of bytes into data_return.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<funcsynopsis id='_xread16'>
+<funcprototype>
+ <funcdef><function>_XRead16</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>short<parameter> *data_return</parameter></paramdef>
+ <paramdef>long<parameter> nbytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the buffer.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nbytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes required.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>_XRead16</function>
+function reads the specified number of bytes,
+unpacking them as 16-bit quantities,
+into the specified array as shorts.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<funcsynopsis id='_xread32'>
+<funcprototype>
+ <funcdef><function>_XRead32</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>long<parameter> *data_return</parameter></paramdef>
+ <paramdef>long<parameter> nbytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the buffer.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nbytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes required.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>_XRead32</function>
+function reads the specified number of bytes,
+unpacking them as 32-bit quantities,
+into the specified array as longs.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<funcsynopsis id='_xread16pad'>
+<funcprototype>
+ <funcdef><function>_XRead16Pad</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>short<parameter> *data_return</parameter></paramdef>
+ <paramdef>long<parameter> nbytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the buffer.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nbytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes required.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>_XRead16Pad</function>
+function reads the specified number of bytes,
+unpacking them as 16-bit quantities,
+into the specified array as shorts.
+If the number of bytes is not a multiple of four,
+<function>_XRead16Pad</function>
+reads and discards up to two additional pad bytes.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<funcsynopsis id='_xreadpad'>
+<funcprototype>
+ <funcdef><function>_XReadPad</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *data_return</parameter></paramdef>
+ <paramdef>long<parameter> nbytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the buffer.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nbytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes required.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>_XReadPad</function>
+function reads the specified number of bytes into data_return.
+If the number of bytes is not a multiple of four,
+<function>_XReadPad</function>
+reads and discards up to three additional pad bytes.
+</para>
+<para>
+<!-- .LP -->
+Each protocol request is a little different.
+For further information,
+see the Xlib sources for examples.
+<!-- .SH -->
+Synchronous Calling
+</para>
+<para>
+<!-- .LP -->
+Each procedure should have a call, just before returning to the user,
+to a macro called
+<systemitem>SyncHandle</systemitem>.
+If synchronous mode is enabled (see
+<function>XSynchronize</function>),
+the request is sent immediately.
+The library, however, waits until any error the procedure could generate
+at the server has been handled.
+<!-- .SH -->
+Allocating and Deallocating Memory
+</para>
+<para>
+<!-- .LP -->
+To support the possible reentry of these procedures,
+you must observe several conventions when allocating and deallocating memory,
+most often done when returning data to the user from the window
+system of a size the caller could not know in advance
+(for example, a list of fonts or a list of extensions).
+The standard C library functions on many systems
+are not protected against signals or other multithreaded uses.
+The following analogies to standard I/O library functions
+have been defined:
+</para>
+<para>
+<!-- .LP -->
+These should be used in place of any calls you would make to the normal
+C library functions.
+</para>
+<para>
+<!-- .LP -->
+If you need a single scratch buffer inside a critical section
+(for example, to pack and unpack data to and from the wire protocol),
+the general memory allocators may be too expensive to use
+(particularly in output functions, which are performance critical).
+The following function returns a scratch buffer for use within a
+critical section:
+<indexterm significance="preferred"><primary>_XAllocScratch</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='_xallocscratch'>
+<funcprototype>
+ <funcdef>char *<function>_XAllocScratch</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> nbytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nbytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes required.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+This storage must only be used inside of a critical section of your
+stub. The returned pointer cannot be assumed valid after any call
+that might permit another thread to execute inside Xlib. For example,
+the pointer cannot be assumed valid after any use of the
+<function>GetReq</function>
+or
+<function>Data</function>
+families of macros,
+after any use of
+<function>_XReply</function>,
+or after any use of the
+<function>_XSend</function>
+or
+<function>_XRead</function>
+families of functions.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+The following function returns a scratch buffer for use across
+critical sections:
+<indexterm significance="preferred"><primary>_XAllocTemp</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='_xalloctemp'>
+<funcprototype>
+ <funcdef>char *<function>_XAllocTemp</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> nbytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nbytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes required.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+This storage can be used across calls that might permit another thread to
+execute inside Xlib. The storage must be explicitly returned to Xlib.
+The following function returns the storage:
+<indexterm significance="preferred"><primary>_XFreeTemp</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='_xfreetemp'>
+<funcprototype>
+ <funcdef>void <function>_XFreeTemp</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *buf</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> nbytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>buf</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the buffer to return.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nbytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the size of the buffer.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+You must pass back the same pointer and size that were returned by
+<function>_XAllocTemp</function>.
+<!-- .SH -->
+Portability Considerations
+</para>
+<para>
+<!-- .LP -->
+Many machine architectures,
+including many of the more recent <acronym>RISC</acronym> architectures,
+do not correctly access data at unaligned locations;
+their compilers pad out structures to preserve this characteristic.
+Many other machines capable of unaligned references pad inside of structures
+as well to preserve alignment, because accessing aligned data is
+usually much faster.
+Because the library and the server use structures to access data at
+arbitrary points in a byte stream,
+all data in request and reply packets <emphasis remap='I'>must</emphasis> be naturally aligned;
+that is, 16-bit data starts on 16-bit boundaries in the request
+and 32-bit data on 32-bit boundaries.
+All requests <emphasis remap='I'>must</emphasis> be a multiple of 32 bits in length to preserve
+the natural alignment in the data stream.
+You must pad structures out to 32-bit boundaries.
+Pad information does not have to be zeroed unless you want to
+preserve such fields for future use in your protocol requests.
+Floating point varies radically between machines and should be
+avoided completely if at all possible.
+</para>
+<para>
+<!-- .LP -->
+This code may run on machines with 16-bit ints.
+So, if any integer argument, variable, or return value either can take
+only nonnegative values or is declared as a
+<type>CARD16</type>
+in the protocol, be sure to declare it as
+<type>unsigned</type>
+<type>int</type>
+and not as
+<type>int</type>.
+(This, of course, does not apply to Booleans or enumerations.)
+</para>
+<para>
+<!-- .LP -->
+Similarly,
+if any integer argument or return value is declared
+<type>CARD32</type>
+in the protocol,
+declare it as an
+<type>unsigned</type>
+<type>long</type>
+and not as
+<type>int</type>
+or
+<type>long</type>.
+This also goes for any internal variables that may
+take on values larger than the maximum 16-bit
+<type>unsigned</type>
+<type>int</type>.
+</para>
+<para>
+<!-- .LP -->
+The library currently assumes that a
+<type>char</type>
+is 8 bits, a
+<type>short</type>
+is 16 bits, an
+<type>int</type>
+is 16 or 32 bits, and a
+<type>long</type>
+is 32 bits.
+The
+<function>PackData</function>
+macro is a half-hearted attempt to deal with the possibility of 32 bit shorts.
+However, much more work is needed to make this work properly.
+<!-- .SH -->
+Deriving the Correct Extension Opcode
+</para>
+<para>
+<!-- .LP -->
+The remaining problem a writer of an extension stub procedure faces that
+the core protocol does not face is to map from the call to the proper
+major and minor opcodes.
+While there are a number of strategies,
+the simplest and fastest is outlined below.
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Declare an array of pointers, _NFILE long (this is normally found
+in
+&lt;stdio.h&gt;
+and is the number of file descriptors supported on the system)
+of type
+<structname>XExtCodes</structname>.
+Make sure these are all initialized to NULL.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+When your stub is entered, your initialization test is just to use
+the display pointer passed in to access the file descriptor and an index
+into the array.
+If the entry is NULL, then this is the first time you
+are entering the procedure for this display.
+Call your initialization procedure and pass to it the display pointer.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Once in your initialization procedure, call
+<function>XInitExtension</function>;
+if it succeeds, store the pointer returned into this array.
+Make sure to establish a close display handler to allow you to zero the entry.
+Do whatever other initialization your extension requires.
+(For example, install event handlers and so on.)
+Your initialization procedure would normally return a pointer to the
+<structname>XExtCodes</structname>
+structure for this extension, which is what would normally
+be found in your array of pointers.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+After returning from your initialization procedure,
+the stub can now continue normally, because it has its major opcode safely
+in its hand in the
+<structname>XExtCodes</structname>
+structure.
+<!-- .bp -->
+ </para>
+ </listitem>
+</itemizedlist>
+</appendix>
diff --git a/libX11/specs/libX11/AppD.xml b/libX11/specs/libX11/AppD.xml
index 0d060069e..afe65907d 100644
--- a/libX11/specs/libX11/AppD.xml
+++ b/libX11/specs/libX11/AppD.xml
@@ -1,1889 +1,1889 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE appendix PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<appendix id="compatibility_functions">
-<title>Compatibility Functions</title>
-<para>
-The X Version 11 and X Version 10 functions discussed in this appendix
-are obsolete, have been superseded by newer X Version 11 functions,
-and are maintained for compatibility reasons only.
-</para>
-<sect1 id="X_Version_11_Compatibility_Functions">
-<title>X Version 11 Compatibility Functions</title>
-<para>
-You can use the X Version 11 compatibility functions to:
-<itemizedlist>
- <listitem>
- <para>
-Set standard properties
- </para>
- </listitem>
- <listitem>
- <para>
-Set and get window sizing hints
- </para>
- </listitem>
- <listitem>
- <para>
-Set and get an
-<structname>XStandardColormap</structname>
-structure
- </para>
- </listitem>
- <listitem>
- <para>
-Parse window geometry
- </para>
- </listitem>
- <listitem>
- <para>
-Get X environment defaults
- </para>
- </listitem>
-</itemizedlist>
-</para>
-<sect2 id="Setting_Standard_Properties">
-<title>Setting Standard Properties</title>
-<para>
-To specify a minimum set of properties describing the simplest application,
-use
-<function>XSetStandardProperties</function>.
-This function has been superseded by
-<function>XSetWMProperties</function>
-and sets all or portions of the
-<property>WM_NAME</property>, <property>WM_ICON_NAME</property>, <property>WM_HINTS</property>, <property>WM_COMMAND</property>,
-and <property>WM_NORMAL_HINTS</property> properties.
-<indexterm significance="preferred"><primary>XSetStandardProperties</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetStandardProperties</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>char<parameter> *window_name</parameter></paramdef>
- <paramdef>char<parameter> *icon_name</parameter></paramdef>
- <paramdef>Pixmap<parameter> icon_pixmap</parameter></paramdef>
- <paramdef>char<parameter> **argv</parameter></paramdef>
- <paramdef>int<parameter> argc</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>window_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window name,
-which should be a null-terminated string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>icon_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the icon name,
-which should be a null-terminated string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>icon_pixmap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the bitmap that is to be used for the icon or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>argv</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the application's argument list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>argc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of arguments.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a pointer to the size hints for the window in its normal state.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetStandardProperties</function>
-function provides a means by which simple applications set the
-most essential properties with a single call.
-<function>XSetStandardProperties</function>
-should be used to give a window manager some information about
-your program's preferences.
-It should not be used by applications that need
-to communicate more information than is possible with
-<function>XSetStandardProperties</function>.
-(Typically, argv is the argv array of your main program.)
-If the strings are not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetStandardProperties</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Setting_and_Getting_Window_Sizing_Hints">
-<title>Setting and Getting Window Sizing Hints</title>
-<para>
-Xlib provides functions that you can use to set or get window sizing hints.
-The functions discussed in this section use the flags and the
-<structname>XSizeHints</structname>
-structure, as defined in the
-<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
-<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-header file and use the <property>WM_NORMAL_HINTS</property> property.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the size hints for a given window in its normal state, use
-<function>XSetNormalHints</function>.
-This function has been superseded by
-<function>XSetWMNormalHints</function>.
-<indexterm significance="preferred"><primary>XSetNormalHints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetNormalHints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a pointer to the size hints for the window in its normal state.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetNormalHints</function>
-function sets the size hints structure for the specified window.
-Applications use
-<function>XSetNormalHints</function>
-to inform the window manager of the size
-or position desirable for that window.
-In addition,
-an application that wants to move or resize itself should call
-<function>XSetNormalHints</function>
-and specify its new desired location and size
-as well as making direct Xlib calls to move or resize.
-This is because window managers may ignore redirected
-configure requests, but they pay attention to property changes.
-</para>
-<para>
-<!-- .LP -->
-To set size hints,
-an application not only must assign values to the appropriate members
-in the hints structure but also must set the flags member of the structure
-to indicate which information is present and where it came from.
-A call to
-<function>XSetNormalHints</function>
-is meaningless, unless the flags member is set to indicate which members of
-the structure have been assigned values.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetNormalHints</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To return the size hints for a window in its normal state, use
-<function>XGetNormalHints</function>.
-This function has been superseded by
-<function>XGetWMNormalHints</function>.
-<indexterm significance="preferred"><primary>XGetNormalHints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetNormalHints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *hints_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hints_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the size hints for the window in its normal state.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetNormalHints</function>
-function returns the size hints for a window in its normal state.
-It returns a nonzero status if it succeeds or zero if
-the application specified no normal size hints for this window.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetNormalHints</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-The next two functions set and read the <property>WM_ZOOM_HINTS</property> property.
-</para>
-<para>
-<!-- .LP -->
-To set the zoom hints for a window, use
-<function>XSetZoomHints</function>.
-This function is no longer supported by the
-<emphasis remap='I'>Inter-Client Communication Conventions Manual</emphasis>.
-<indexterm significance="preferred"><primary>XSetZoomHints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetZoomHints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *zhints</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>zhints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a pointer to the zoom hints.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Many window managers think of windows in one of three states:
-iconic, normal, or zoomed.
-The
-<function>XSetZoomHints</function>
-function provides the window manager with information for the window in the
-zoomed state.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetZoomHints</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To read the zoom hints for a window, use
-<function>XGetZoomHints</function>.
-This function is no longer supported by the
-<emphasis remap='I'>Inter-Client Communication Conventions Manual</emphasis>.
-<indexterm significance="preferred"><primary>XGetZoomHints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetZoomHints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *zhints_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>zhints_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the zoom hints.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetZoomHints</function>
-function returns the size hints for a window in its zoomed state.
-It returns a nonzero status if it succeeds or zero if
-the application specified no zoom size hints for this window.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetZoomHints</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the value of any property of type <property>WM_SIZE_HINTS</property>, use
-<function>XSetSizeHints</function>.
-This function has been superseded by
-<function>XSetWMSizeHints</function>.
-<indexterm significance="preferred"><primary>XSetSizeHints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetSizeHints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
- <paramdef>Atom<parameter> property</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a pointer to the size hints.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>property</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the property name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetSizeHints</function>
-function sets the
-<structname>XSizeHints</structname>
-structure for the named property and the specified window.
-This is used by
-<function>XSetNormalHints</function>
-and
-<function>XSetZoomHints</function>
-and can be used to set the value of any property of type <property>WM_SIZE_HINTS</property>.
-Thus, it may be useful if other properties of that type get defined.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetSizeHints</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadAtom</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To read the value of any property of type <property>WM_SIZE_HINTS</property>, use
-<function>XGetSizeHints</function>.
-This function has been superseded by
-<function>XGetWMSizeHints</function>.
-<indexterm significance="preferred"><primary>XGetSizeHints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetSizeHints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *hints_return</parameter></paramdef>
- <paramdef>Atom<parameter> property</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hints_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the size hints.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>property</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the property name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetSizeHints</function>
-function returns the
-<structname>XSizeHints</structname>
-structure for the named property and the specified window.
-This is used by
-<function>XGetNormalHints</function>
-and
-<function>XGetZoomHints</function>.
-It also can be used to retrieve the value of any property of type
-<property>WM_SIZE_HINTS</property>.
-Thus, it may be useful if other properties of that type get defined.
-<function>XGetSizeHints</function>
-returns a nonzero status if a size hint was defined
-or zero otherwise.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetSizeHints</function>
-can generate
-<errorname>BadAtom</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Getting_and_Setting_an_XStandardColormap_Structure">
-<title>Getting and Setting an XStandardColormap Structure</title>
-<para>
-To get the
-<structname>XStandardColormap</structname>
-structure associated with one of the described atoms, use
-<function>XGetStandardColormap</function>.
-This function has been superseded by
-<function>XGetRGBColormaps</function>.
-<indexterm significance="preferred"><primary>XGetStandardColormap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetStandardColormap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XStandardColormap<parameter> *colormap_return</parameter></paramdef>
- <paramdef>Atom<parameter> property</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the colormap associated with the specified atom.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>property</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the property name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetStandardColormap</function>
-function returns the colormap definition associated with the atom supplied
-as the property argument.
-<function>XGetStandardColormap</function>
-returns a nonzero status if successful and zero otherwise.
-For example,
-to fetch the standard
-<symbol>GrayScale</symbol>
-colormap for a display,
-you use
-<function>XGetStandardColormap</function>
-with the following syntax:
-<programlisting>
-XGetStandardColormap(dpy, DefaultRootWindow(dpy), &amp;cmap, XA_RGB_GRAY_MAP);
-</programlisting>
-See section 14.3 for the semantics of standard colormaps.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetStandardColormap</function>
-can generate
-<errorname>BadAtom</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set a standard colormap, use
-<function>XSetStandardColormap</function>.
-This function has been superseded by
-<function>XSetRGBColormaps</function>.
-<indexterm significance="preferred"><primary>XSetStandardColormap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetStandardColormap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XStandardColormap<parameter> *colormap</parameter></paramdef>
- <paramdef>Atom<parameter> property</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>property</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the property name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetStandardColormap</function>
-function usually is only used by window or session managers.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetStandardColormap</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadAtom</errorname>,
-<errorname>BadDrawable</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Parsing_Window_Geometry">
-<title>Parsing Window Geometry</title>
-<para>
-To parse window geometry given a user-specified position
-and a default position, use
-<function>XGeometry</function>.
-This function has been superseded by
-<function>XWMGeometry</function>.
-<indexterm><primary>Window</primary><secondary>determining location</secondary></indexterm>
-<indexterm significance="preferred"><primary>XGeometry</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XGeometry</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> screen</parameter></paramdef>
- <paramdef>char*position,<parameter> *default_position</parameter></paramdef>
- <paramdef>unsignedint<parameter> bwidth</parameter></paramdef>
- <paramdef>unsignedintfwidth,<parameter> fheight</parameter></paramdef>
- <paramdef>intxadder,<parameter> yadder</parameter></paramdef>
- <paramdef>int*x_return,<parameter> *y_return</parameter></paramdef>
- <paramdef>int*width_return,<parameter> *height_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the screen.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>position</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>default_position</emphasis>
- </term>
- <listitem>
- <para>
-Specify the geometry specifications.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bwidth</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the border width.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>fheight</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>fwidth</emphasis>
- </term>
- <listitem>
- <para>
-Specify the font height and width in pixels (increment size).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>xadder</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>yadder</emphasis>
- </term>
- <listitem>
- <para>
-Specify additional interior padding needed in the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the x and y offsets.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the width and height determined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-You pass in the border width (bwidth),
-size of the increments fwidth and fheight
-(typically font width and height),
-and any additional interior space (xadder and yadder)
-to make it easy to compute the resulting size.
-The
-<function>XGeometry</function>
-function returns the position the window should be placed given a position and
-a default position.
-<function>XGeometry</function>
-determines the placement of
-a window using a geometry specification as specified by
-<function>XParseGeometry</function>
-and the additional information about the window.
-Given a fully qualified default geometry specification and
-an incomplete geometry specification,
-<function>XParseGeometry</function>
-returns a bitmask value as defined above in the
-<function>XParseGeometry</function>
-call,
-by using the position argument.
-</para>
-<para>
-<!-- .LP -->
-The returned width and height will be the width and height specified
-by default_position as overridden by any user-specified position.
-They are not affected by fwidth, fheight, xadder, or yadder.
-The x and y coordinates are computed by using the border width,
-the screen width and height, padding as specified by xadder and yadder,
-and the fheight and fwidth times the width and height from the
-geometry specifications.
-</para>
-</sect2>
-<sect2 id="Getting_the_X_Environment_Defaults">
-<title>Getting the X Environment Defaults</title>
-<para>
-The
-<function>XGetDefault</function>
-function provides a primitive interface to the resource manager facilities
-discussed in chapter 15. <!-- xref -->
-It is only useful in very simple applications.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-<indexterm significance="preferred"><primary>XGetDefault</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XGetDefault</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *program</parameter></paramdef>
- <paramdef>char<parameter> *option</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>program</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the program name for the Xlib defaults (usually argv[0]
-of the main program).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>option</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the option name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetDefault</function>
-function returns the value of the resource <emphasis remap='I'>prog</emphasis>.<emphasis remap='I'>option</emphasis>,
-where <emphasis remap='I'>prog</emphasis> is the program argument with the directory prefix removed
-and <emphasis remap='I'>option</emphasis> must be a single component.
-Note that multilevel resources cannot be used with
-<function>XGetDefault</function>.
-The class "Program.Name" is always used for the resource lookup.
-If the specified option name does not exist for this program,
-<function>XGetDefault</function>
-returns NULL.
-The strings returned by
-<function>XGetDefault</function>
-are owned by Xlib and should not be modified or freed by the client.
-</para>
-<para>
-<!-- .LP -->
-If a database has been set with
-<function>XrmSetDatabase</function>,
-that database is used for the lookup.
-Otherwise, a database is created
-and is set in the display (as if by calling
-<function>XrmSetDatabase</function>).
-The database is created in the current locale.
-To create a database,
-<function>XGetDefault</function>
-uses resources from the RESOURCE_MANAGER property on the root
-window of screen zero.
-If no such property exists,
-a resource file in the user's home directory is used.
-On a <acronym>POSIX</acronym>-conformant system,
-this file is
-<function>"$HOME/.Xdefaults"</function>.
-<indexterm><primary>Files</primary><secondary><filename>$HOME/.Xdefaults</filename></secondary></indexterm>
-After loading these defaults,
-<function>XGetDefault</function>
-merges additional defaults specified by the XENVIRONMENT
-environment variable.
-If XENVIRONMENT is defined,
-it contains a full path name for the additional resource file.
-If XENVIRONMENT is not defined,
-<function>XGetDefault</function>
-looks for
-"<filename>$HOME/.Xdefaults-<replaceable>name</replaceable></filename>" ,
-where <replaceable>name</replaceable> specifies the name of the machine on which the application
-is running.
-</para>
-</sect2>
-</sect1>
-<sect1 id="X_Version_10_Compatibility_Functions">
-<title>X Version 10 Compatibility Functions</title>
-<para>
-You can use the X Version 10 compatibility functions to:
-<itemizedlist>
- <listitem>
- <para>
-Draw and fill polygons and curves
- </para>
- </listitem>
- <listitem>
- <para>
-Associate user data with a value
- </para>
- </listitem>
-</itemizedlist>
-</para>
-<sect2 id="Drawing_and_Filling_Polygons_and_Curves">
-<title>Drawing and Filling Polygons and Curves</title>
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to draw or fill
-arbitrary polygons or curves.
-These functions are provided mainly for compatibility with X Version 10
-and have no server support.
-That is, they call other Xlib functions, not the server directly.
-Thus, if you just have straight lines to draw, using
-<function>XDrawLines</function>
-<indexterm><primary>XDrawLines</primary></indexterm>
-or
-<function>XDrawSegments</function>
-<indexterm><primary>XDrawSegments</primary></indexterm>
-is much faster.
-</para>
-<para>
-<!-- .LP -->
-The functions discussed here provide all the functionality of the
-X Version 10 functions
-<function>XDraw</function>,
-<indexterm ><primary>X10 compatibility</primary><secondary>XDraw</secondary></indexterm>
-<function>XDrawFilled</function>,
-<indexterm><primary>X10 compatibility</primary><secondary>XDrawFilled</secondary></indexterm>
-<function>XDrawPatterned</function>,
-<indexterm ><primary>X10 compatibility</primary><secondary>XDrawPatterned</secondary></indexterm>
-<function>XDrawDashed</function>,
-<indexterm><primary>X10 compatibility</primary><secondary>XDrawDashed</secondary></indexterm>
-and
-<function>XDrawTiled</function>.
-<indexterm><primary>X10 compatibility</primary><secondary>XDrawTiled</secondary></indexterm>
-They are as compatible as possible given X Version 11's new line-drawing
-functions.
-One thing to note, however, is that
-<function>VertexDrawLastPoint</function>
-is no longer supported.
-Also, the error status returned is the opposite of what it was under
-X Version 10 (this is the X Version 11 standard error status).
-<function>XAppendVertex</function>
-and
-<function>XClearVertexFlag</function>
-from X Version 10 also are not supported.
-</para>
-<para>
-<!-- .LP -->
-Just how the graphics context you use is set up actually
-determines whether you get dashes or not, and so on.
-Lines are properly joined if they connect and include
-the closing of a closed figure (see
-<function>XDrawLines</function>).
-The functions discussed here fail (return zero) only if they run out of memory
-or are passed a
-<structname>Vertex</structname>
-list that has a
-<structname>Vertex</structname>
-with
-<symbol>VertexStartClosed</symbol>
-set that is not followed by a
-<structname>Vertex</structname>
-with
-<symbol>VertexEndClosed</symbol>
-set.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To achieve the effects of the X Version 10
-<function>XDraw</function>,
-<indexterm ><primary>X10 compatibility</primary><secondary>XDraw</secondary></indexterm>
-<function>XDrawDashed</function>,
-<indexterm><primary>X10 compatibility</primary><secondary>XDrawDashed</secondary></indexterm>
-and
-<function>XDrawPatterned</function>,
-<indexterm ><primary>X10 compatibility</primary><secondary>XDrawPatterned</secondary></indexterm>
-use
-<function>XDraw</function>.
-</para>
-
-<para>
-#include &lt;X11/X10.h&gt;
-</para>
-
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XDraw</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>Vertex<parameter> *vlist</parameter></paramdef>
- <paramdef>int<parameter> vcount</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>vlist</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a pointer to the list of vertices that indicate what to draw.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>vcount</emphasis>
- </term>
- <listitem>
- <para>
-Specifies how many vertices are in vlist.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDraw</function>
-function draws an arbitrary polygon or curve.
-The figure drawn is defined by the specified list of vertices (vlist).
-The points are connected by lines as specified in the flags in the
-vertex structure.
-</para>
-<para>
-<!-- .LP -->
-Each Vertex, as defined in
-<filename class="headerfile">&lt;X11/X10.h&gt;</filename>,
-<indexterm type="file"><primary><filename class="headerfile">X11/X10.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/X10.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/X10.h&gt;</filename></secondary></indexterm>
-is a structure with the following members:
-<indexterm significance="preferred"><primary>Vertex</primary></indexterm>
-<synopsis>
-typedef struct _Vertex {
- short x,y;
- unsigned short flags;
-} Vertex;
-</synopsis>
-The x and y members are the coordinates of the vertex
-that are relative to either the upper left inside corner of the drawable
-(if
-<symbol>VertexRelative</symbol>
-is zero) or the previous vertex (if
-<symbol>VertexRelative</symbol>
-is one).
-</para>
-<para>
-<!-- .LP -->
-The flags, as defined in
-<filename class="headerfile">&lt;X11/X10.h&gt;</filename>,
-<indexterm type="file"><primary><filename class="headerfile">X11/X10.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/X10.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/X10.h&gt;</filename></secondary></indexterm>
-are as follows:
-<indexterm significance="preferred"><primary>VertexRelative</primary></indexterm>
-<indexterm significance="preferred"><primary>VertexDontDraw</primary></indexterm>
-<indexterm significance="preferred"><primary>VertexCurved</primary></indexterm>
-<indexterm significance="preferred"><primary>VertexStartClosed</primary></indexterm>
-<indexterm significance="preferred"><primary>VertexEndClosed</primary></indexterm>
-<!-- .sM -->
-
-<synopsis>
-VertexRelative 0x0001 /* else absolute */
-VertexDontDraw 0x0002 /* else draw */
-VertexCurved 0x0004 /* else straight */
-VertexStartClosed 0x0008 /* else not */
-VertexEndClosed 0x0010 /* else not */
-</synopsis>
-
-<itemizedlist>
- <listitem>
- <para>
-If
-<symbol>VertexRelative</symbol>
-is not set,
-the coordinates are absolute (that is, relative to the drawable's origin).
-The first vertex must be an absolute vertex.
- </para>
- </listitem>
- <listitem>
- <para>
-If
-<symbol>VertexDontDraw</symbol>
-is one,
-no line or curve is drawn from the previous vertex to this one.
-This is analogous to picking up the pen and moving to another place
-before drawing another line.
- </para>
- </listitem>
- <listitem>
- <para>
-If
-<symbol>VertexCurved</symbol>
-is one,
-a spline algorithm is used to draw a smooth curve from the previous vertex
-through this one to the next vertex.
-Otherwise, a straight line is drawn from the previous vertex to this one.
-It makes sense to set
-<symbol>VertexCurved</symbol>
-to one only if a previous and next vertex are both defined
-(either explicitly in the array or through the definition of a closed
-curve).
- </para>
- </listitem>
- <listitem>
- <para>
-It is permissible for
-<symbol>VertexDontDraw</symbol>
-bits and
-<symbol>VertexCurved</symbol>
-bits both to be one.
-This is useful if you want to define the previous point for the smooth curve
-but do not want an actual curve drawing to start until this point.
- </para>
- </listitem>
- <listitem>
- <para>
-If
-<symbol>VertexStartClosed</symbol>
-is one,
-then this point marks the beginning of a closed curve.
-This vertex must be followed later in the array by another vertex
-whose effective coordinates are identical
-and that has a
-<symbol>VertexEndClosed</symbol>
-bit of one.
-The points in between form a cycle to determine predecessor
-and successor vertices for the spline algorithm.
- </para>
- </listitem>
-</itemizedlist>
-</para>
-<para>
-<!-- .LP -->
-This function uses these GC components:
-function, plane-mask, line-width, line-style, cap-style, join-style,
-fill-style, subwindow-mode, clip-x-origin, clip-y-origin, and
-clip-mask.
-It also uses these GC mode-dependent components:
-foreground, background, tile, stipple,
-tile-stipple-x-origin, tile-stipple-y-origin, dash-offset, and dash-list.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To achieve the effects of the X Version 10
-<function>XDrawTiled</function>
-<indexterm><primary>X10 compatibility</primary><secondary>XDrawTiled</secondary></indexterm>
-and
-<function>XDrawFilled</function>,
-<indexterm><primary>X10 compatibility</primary><secondary>XDrawFilled</secondary></indexterm>
-use
-<function>XDrawFilled</function>.
-</para>
-
-<para>#include &lt;X11/X10.h&gt;</para>
-
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XDrawFilled</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>Vertex<parameter> *vlist</parameter></paramdef>
- <paramdef>int<parameter> vcount</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>vlist</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a pointer to the list of vertices that indicate what to draw.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>vcount</emphasis>
- </term>
- <listitem>
- <para>
-Specifies how many vertices are in vlist.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDrawFilled</function>
-function draws arbitrary polygons or curves and then fills them.
-</para>
-<para>
-<!-- .LP -->
-This function uses these GC components:
-function, plane-mask, line-width, line-style, cap-style, join-style,
-fill-style, subwindow-mode, clip-x-origin, clip-y-origin, and
-clip-mask.
-It also uses these GC mode-dependent components:
-foreground, background, tile, stipple,
-tile-stipple-x-origin, tile-stipple-y-origin,
-dash-offset, dash-list, fill-style, and fill-rule.
-</para>
-</sect2>
-<sect2 id="Associating_User_Data_with_a_Value">
-<title>Associating User Data with a Value</title>
-<para>
-<!-- .LP -->
-These functions have been superseded by the context management functions
-(see section 16.10).
-It is often necessary to associate arbitrary information with resource IDs.
-Xlib provides the
-<function>XAssocTable</function>
-functions that you can use to make such an association.
-<indexterm><primary>Hash Lookup</primary></indexterm>
-<indexterm><primary>Window</primary><secondary>IDs</secondary></indexterm>
-<indexterm><primary>Resource IDs</primary></indexterm>
-Application programs often need to be able to easily refer to
-their own data structures when an event arrives.
-The
-<function>XAssocTable</function>
-system provides users of the X library with a method
-for associating their own data structures with X resources
-(<type>Pixmap</type>s,
-<type>Font</type>s,
-<type>Window</type>s,
-and so on).
-</para>
-<para>
-<!-- .LP -->
-An
-<function>XAssocTable</function>
-can be used to type X resources.
-For example, the user
-may want to have three or four types of windows,
-each with different properties.
-This can be accomplished by associating each X window ID
-with a pointer to a window property data structure defined by the
-user.
-A generic type has been defined in the X library for resource IDs.
-It is called an XID.
-</para>
-<para>
-<!-- .LP -->
-There are a few guidelines that should be observed when using an
-<function>XAssocTable</function> :
-</para>
-<itemizedlist>
- <listitem>
- <para>
-All XIDs are relative to the specified display.
- </para>
- </listitem>
- <listitem>
- <para>
-Because of the hashing scheme used by the association mechanism,
-the following rules for determining the size of a
-<function>XAssocTable</function>
-should be followed.
-Associations will be made and looked up more
-efficiently if the table size (number of buckets in the hashing
-system) is a power of two and if there are not more than 8 XIDs per
-bucket.
- </para>
- </listitem>
-</itemizedlist>
-
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To return a pointer to a new
-<function>XAssocTable</function>,
-use
-<function>XCreateAssocTable</function>.
-<indexterm significance="preferred"><primary>XCreateAssocTable</primary></indexterm>
-<!-- .sM -->
-</para>
-<funcsynopsis>
-<funcprototype>
- <funcdef>XAssocTable *<function>XCreateAssocTable</function></funcdef>
- <paramdef>int<parameter> size</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>size</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of buckets in the hash system of
-<function>XAssocTable</function>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The size argument specifies the number of buckets in the
-hash system of
-<function>XAssocTable</function>.
-For reasons of efficiency the number of buckets
-should be a power of two.
-Some size suggestions might be: use 32 buckets per 100 objects,
-and a reasonable maximum number of objects per buckets is 8.
-If an error allocating memory for the
-<function>XAssocTable</function>
-occurs,
-a NULL pointer is returned.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create an entry in a given
-<function>XAssocTable</function>,
-use
-<function>XMakeAssoc</function>.
-<indexterm significance="preferred"><primary>XMakeAssoc</primary></indexterm>
-<!-- .sM -->
-</para>
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XMakeAssoc</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XAssocTable<parameter> *table</parameter></paramdef>
- <paramdef>XID<parameter> x_id</parameter></paramdef>
- <paramdef>char<parameter> *data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>table</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the assoc table.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x_id</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the X resource ID.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the data to be associated with the X resource ID.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XMakeAssoc</function>
-function inserts data into an
-<function>XAssocTable</function>
-keyed on an XID.
-Data is inserted into the table only once.
-Redundant inserts are ignored.
-The queue in each association bucket is sorted from the lowest XID to
-the highest XID.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain data from a given
-<function>XAssocTable</function>,
-use
-<function>XLookUpAssoc</function>.
-<indexterm significance="preferred"><primary>XLookUpAssoc</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XLookUpAssoc</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XAssocTable<parameter> *table</parameter></paramdef>
- <paramdef>XID<parameter> x_id</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>table</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the assoc table.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x_id</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the X resource ID.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XLookUpAssoc</function>
-function retrieves the data stored in an
-<function>XAssocTable</function>
-by its XID.
-If an appropriately matching XID can be found in the table,
-<function>XLookUpAssoc</function>
-returns the data associated with it.
-If the x_id cannot be found in the table,
-it returns NULL.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To delete an entry from a given
-<function>XAssocTable</function>,
-use
-<function>XDeleteAssoc</function>.
-<indexterm significance="preferred"><primary>XDeleteAssoc</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDeleteAssoc</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XAssocTable<parameter> *table</parameter></paramdef>
- <paramdef>XID<parameter> x_id</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>table</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the assoc table.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x_id</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the X resource ID.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDeleteAssoc</function>
-function deletes an association in an
-<function>XAssocTable</function>
-keyed on its XID.
-Redundant deletes (and deletes of nonexistent XIDs) are ignored.
-Deleting associations in no way impairs the performance of an
-<function>XAssocTable</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To free the memory associated with a given
-<function>XAssocTable</function>,
-use
-<function>XDestroyAssocTable</function>.
-</para>
-<indexterm significance="preferred"><primary>XDestroyAssocTable</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDestroyAssocTable</function></funcdef>
- <paramdef>XAssocTable<parameter> *table</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>table</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the assoc table.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</sect2>
-</sect1>
-</appendix>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE appendix PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<appendix id="compatibility_functions">
+<title>Compatibility Functions</title>
+<para>
+The X Version 11 and X Version 10 functions discussed in this appendix
+are obsolete, have been superseded by newer X Version 11 functions,
+and are maintained for compatibility reasons only.
+</para>
+<sect1 id="X_Version_11_Compatibility_Functions">
+<title>X Version 11 Compatibility Functions</title>
+<para>
+You can use the X Version 11 compatibility functions to:
+<itemizedlist>
+ <listitem>
+ <para>
+Set standard properties
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and get window sizing hints
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and get an
+<structname>XStandardColormap</structname>
+structure
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Parse window geometry
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Get X environment defaults
+ </para>
+ </listitem>
+</itemizedlist>
+</para>
+<sect2 id="Setting_Standard_Properties">
+<title>Setting Standard Properties</title>
+<para>
+To specify a minimum set of properties describing the simplest application,
+use
+<function>XSetStandardProperties</function>.
+This function has been superseded by
+<function>XSetWMProperties</function>
+and sets all or portions of the
+<property>WM_NAME</property>, <property>WM_ICON_NAME</property>, <property>WM_HINTS</property>, <property>WM_COMMAND</property>,
+and <property>WM_NORMAL_HINTS</property> properties.
+<indexterm significance="preferred"><primary>XSetStandardProperties</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetstandardproperties'>
+<funcprototype>
+ <funcdef><function>XSetStandardProperties</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>char<parameter> *window_name</parameter></paramdef>
+ <paramdef>char<parameter> *icon_name</parameter></paramdef>
+ <paramdef>Pixmap<parameter> icon_pixmap</parameter></paramdef>
+ <paramdef>char<parameter> **argv</parameter></paramdef>
+ <paramdef>int<parameter> argc</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>window_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window name,
+which should be a null-terminated string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>icon_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the icon name,
+which should be a null-terminated string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>icon_pixmap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the bitmap that is to be used for the icon or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>argv</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the application's argument list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>argc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of arguments.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a pointer to the size hints for the window in its normal state.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetStandardProperties</function>
+function provides a means by which simple applications set the
+most essential properties with a single call.
+<function>XSetStandardProperties</function>
+should be used to give a window manager some information about
+your program's preferences.
+It should not be used by applications that need
+to communicate more information than is possible with
+<function>XSetStandardProperties</function>.
+(Typically, argv is the argv array of your main program.)
+If the strings are not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetStandardProperties</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Setting_and_Getting_Window_Sizing_Hints">
+<title>Setting and Getting Window Sizing Hints</title>
+<para>
+Xlib provides functions that you can use to set or get window sizing hints.
+The functions discussed in this section use the flags and the
+<structname>XSizeHints</structname>
+structure, as defined in the
+<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
+<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+header file and use the <property>WM_NORMAL_HINTS</property> property.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the size hints for a given window in its normal state, use
+<function>XSetNormalHints</function>.
+This function has been superseded by
+<function>XSetWMNormalHints</function>.
+<indexterm significance="preferred"><primary>XSetNormalHints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetnormalhints'>
+<funcprototype>
+ <funcdef><function>XSetNormalHints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a pointer to the size hints for the window in its normal state.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetNormalHints</function>
+function sets the size hints structure for the specified window.
+Applications use
+<function>XSetNormalHints</function>
+to inform the window manager of the size
+or position desirable for that window.
+In addition,
+an application that wants to move or resize itself should call
+<function>XSetNormalHints</function>
+and specify its new desired location and size
+as well as making direct Xlib calls to move or resize.
+This is because window managers may ignore redirected
+configure requests, but they pay attention to property changes.
+</para>
+<para>
+<!-- .LP -->
+To set size hints,
+an application not only must assign values to the appropriate members
+in the hints structure but also must set the flags member of the structure
+to indicate which information is present and where it came from.
+A call to
+<function>XSetNormalHints</function>
+is meaningless, unless the flags member is set to indicate which members of
+the structure have been assigned values.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetNormalHints</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To return the size hints for a window in its normal state, use
+<function>XGetNormalHints</function>.
+This function has been superseded by
+<function>XGetWMNormalHints</function>.
+<indexterm significance="preferred"><primary>XGetNormalHints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetnormalhints'>
+<funcprototype>
+ <funcdef>Status <function>XGetNormalHints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *hints_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hints_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the size hints for the window in its normal state.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetNormalHints</function>
+function returns the size hints for a window in its normal state.
+It returns a nonzero status if it succeeds or zero if
+the application specified no normal size hints for this window.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetNormalHints</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+The next two functions set and read the <property>WM_ZOOM_HINTS</property> property.
+</para>
+<para>
+<!-- .LP -->
+To set the zoom hints for a window, use
+<function>XSetZoomHints</function>.
+This function is no longer supported by the
+<emphasis remap='I'>Inter-Client Communication Conventions Manual</emphasis>.
+<indexterm significance="preferred"><primary>XSetZoomHints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetzoomhints'>
+<funcprototype>
+ <funcdef><function>XSetZoomHints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *zhints</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>zhints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a pointer to the zoom hints.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Many window managers think of windows in one of three states:
+iconic, normal, or zoomed.
+The
+<function>XSetZoomHints</function>
+function provides the window manager with information for the window in the
+zoomed state.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetZoomHints</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To read the zoom hints for a window, use
+<function>XGetZoomHints</function>.
+This function is no longer supported by the
+<emphasis remap='I'>Inter-Client Communication Conventions Manual</emphasis>.
+<indexterm significance="preferred"><primary>XGetZoomHints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetzoomhints'>
+<funcprototype>
+ <funcdef>Status <function>XGetZoomHints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *zhints_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>zhints_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the zoom hints.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetZoomHints</function>
+function returns the size hints for a window in its zoomed state.
+It returns a nonzero status if it succeeds or zero if
+the application specified no zoom size hints for this window.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetZoomHints</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the value of any property of type <property>WM_SIZE_HINTS</property>, use
+<function>XSetSizeHints</function>.
+This function has been superseded by
+<function>XSetWMSizeHints</function>.
+<indexterm significance="preferred"><primary>XSetSizeHints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetsizehints'>
+<funcprototype>
+ <funcdef><function>XSetSizeHints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
+ <paramdef>Atom<parameter> property</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a pointer to the size hints.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>property</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the property name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetSizeHints</function>
+function sets the
+<structname>XSizeHints</structname>
+structure for the named property and the specified window.
+This is used by
+<function>XSetNormalHints</function>
+and
+<function>XSetZoomHints</function>
+and can be used to set the value of any property of type <property>WM_SIZE_HINTS</property>.
+Thus, it may be useful if other properties of that type get defined.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetSizeHints</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadAtom</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To read the value of any property of type <property>WM_SIZE_HINTS</property>, use
+<function>XGetSizeHints</function>.
+This function has been superseded by
+<function>XGetWMSizeHints</function>.
+<indexterm significance="preferred"><primary>XGetSizeHints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetsizehints'>
+<funcprototype>
+ <funcdef>Status <function>XGetSizeHints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *hints_return</parameter></paramdef>
+ <paramdef>Atom<parameter> property</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hints_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the size hints.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>property</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the property name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetSizeHints</function>
+function returns the
+<structname>XSizeHints</structname>
+structure for the named property and the specified window.
+This is used by
+<function>XGetNormalHints</function>
+and
+<function>XGetZoomHints</function>.
+It also can be used to retrieve the value of any property of type
+<property>WM_SIZE_HINTS</property>.
+Thus, it may be useful if other properties of that type get defined.
+<function>XGetSizeHints</function>
+returns a nonzero status if a size hint was defined
+or zero otherwise.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetSizeHints</function>
+can generate
+<errorname>BadAtom</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Getting_and_Setting_an_XStandardColormap_Structure">
+<title>Getting and Setting an XStandardColormap Structure</title>
+<para>
+To get the
+<structname>XStandardColormap</structname>
+structure associated with one of the described atoms, use
+<function>XGetStandardColormap</function>.
+This function has been superseded by
+<function>XGetRGBColormaps</function>.
+<indexterm significance="preferred"><primary>XGetStandardColormap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetstandardcolormap'>
+<funcprototype>
+ <funcdef>Status <function>XGetStandardColormap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XStandardColormap<parameter> *colormap_return</parameter></paramdef>
+ <paramdef>Atom<parameter> property</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the colormap associated with the specified atom.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>property</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the property name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetStandardColormap</function>
+function returns the colormap definition associated with the atom supplied
+as the property argument.
+<function>XGetStandardColormap</function>
+returns a nonzero status if successful and zero otherwise.
+For example,
+to fetch the standard
+<symbol>GrayScale</symbol>
+colormap for a display,
+you use
+<function>XGetStandardColormap</function>
+with the following syntax:
+<programlisting>
+XGetStandardColormap(dpy, DefaultRootWindow(dpy), &amp;cmap, XA_RGB_GRAY_MAP);
+</programlisting>
+See section 14.3 for the semantics of standard colormaps.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetStandardColormap</function>
+can generate
+<errorname>BadAtom</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set a standard colormap, use
+<function>XSetStandardColormap</function>.
+This function has been superseded by
+<function>XSetRGBColormaps</function>.
+<indexterm significance="preferred"><primary>XSetStandardColormap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetstandardcolormap'>
+<funcprototype>
+ <funcdef><function>XSetStandardColormap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XStandardColormap<parameter> *colormap</parameter></paramdef>
+ <paramdef>Atom<parameter> property</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>property</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the property name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetStandardColormap</function>
+function usually is only used by window or session managers.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetStandardColormap</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadAtom</errorname>,
+<errorname>BadDrawable</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Parsing_Window_Geometry">
+<title>Parsing Window Geometry</title>
+<para>
+To parse window geometry given a user-specified position
+and a default position, use
+<function>XGeometry</function>.
+This function has been superseded by
+<function>XWMGeometry</function>.
+<indexterm><primary>Window</primary><secondary>determining location</secondary></indexterm>
+<indexterm significance="preferred"><primary>XGeometry</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgeometry'>
+<funcprototype>
+ <funcdef>int <function>XGeometry</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> screen</parameter></paramdef>
+ <paramdef>char*position,<parameter> *default_position</parameter></paramdef>
+ <paramdef>unsignedint<parameter> bwidth</parameter></paramdef>
+ <paramdef>unsignedintfwidth,<parameter> fheight</parameter></paramdef>
+ <paramdef>intxadder,<parameter> yadder</parameter></paramdef>
+ <paramdef>int*x_return,<parameter> *y_return</parameter></paramdef>
+ <paramdef>int*width_return,<parameter> *height_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the screen.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>position</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>default_position</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the geometry specifications.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bwidth</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the border width.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>fheight</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>fwidth</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the font height and width in pixels (increment size).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>xadder</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>yadder</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify additional interior padding needed in the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the x and y offsets.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the width and height determined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+You pass in the border width (bwidth),
+size of the increments fwidth and fheight
+(typically font width and height),
+and any additional interior space (xadder and yadder)
+to make it easy to compute the resulting size.
+The
+<function>XGeometry</function>
+function returns the position the window should be placed given a position and
+a default position.
+<function>XGeometry</function>
+determines the placement of
+a window using a geometry specification as specified by
+<function>XParseGeometry</function>
+and the additional information about the window.
+Given a fully qualified default geometry specification and
+an incomplete geometry specification,
+<function>XParseGeometry</function>
+returns a bitmask value as defined above in the
+<function>XParseGeometry</function>
+call,
+by using the position argument.
+</para>
+<para>
+<!-- .LP -->
+The returned width and height will be the width and height specified
+by default_position as overridden by any user-specified position.
+They are not affected by fwidth, fheight, xadder, or yadder.
+The x and y coordinates are computed by using the border width,
+the screen width and height, padding as specified by xadder and yadder,
+and the fheight and fwidth times the width and height from the
+geometry specifications.
+</para>
+</sect2>
+<sect2 id="Getting_the_X_Environment_Defaults">
+<title>Getting the X Environment Defaults</title>
+<para>
+The
+<function>XGetDefault</function>
+function provides a primitive interface to the resource manager facilities
+discussed in chapter 15. <!-- xref -->
+It is only useful in very simple applications.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+<indexterm significance="preferred"><primary>XGetDefault</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetdefault'>
+<funcprototype>
+ <funcdef>char *<function>XGetDefault</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *program</parameter></paramdef>
+ <paramdef>char<parameter> *option</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>program</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the program name for the Xlib defaults (usually argv[0]
+of the main program).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>option</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the option name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetDefault</function>
+function returns the value of the resource <emphasis remap='I'>prog</emphasis>.<emphasis remap='I'>option</emphasis>,
+where <emphasis remap='I'>prog</emphasis> is the program argument with the directory prefix removed
+and <emphasis remap='I'>option</emphasis> must be a single component.
+Note that multilevel resources cannot be used with
+<function>XGetDefault</function>.
+The class "Program.Name" is always used for the resource lookup.
+If the specified option name does not exist for this program,
+<function>XGetDefault</function>
+returns NULL.
+The strings returned by
+<function>XGetDefault</function>
+are owned by Xlib and should not be modified or freed by the client.
+</para>
+<para>
+<!-- .LP -->
+If a database has been set with
+<function>XrmSetDatabase</function>,
+that database is used for the lookup.
+Otherwise, a database is created
+and is set in the display (as if by calling
+<function>XrmSetDatabase</function>).
+The database is created in the current locale.
+To create a database,
+<function>XGetDefault</function>
+uses resources from the RESOURCE_MANAGER property on the root
+window of screen zero.
+If no such property exists,
+a resource file in the user's home directory is used.
+On a <acronym>POSIX</acronym>-conformant system,
+this file is
+<function>"$HOME/.Xdefaults"</function>.
+<indexterm><primary>Files</primary><secondary><filename>$HOME/.Xdefaults</filename></secondary></indexterm>
+After loading these defaults,
+<function>XGetDefault</function>
+merges additional defaults specified by the XENVIRONMENT
+environment variable.
+If XENVIRONMENT is defined,
+it contains a full path name for the additional resource file.
+If XENVIRONMENT is not defined,
+<function>XGetDefault</function>
+looks for
+"<filename>$HOME/.Xdefaults-<replaceable>name</replaceable></filename>" ,
+where <replaceable>name</replaceable> specifies the name of the machine on which the application
+is running.
+</para>
+</sect2>
+</sect1>
+<sect1 id="X_Version_10_Compatibility_Functions">
+<title>X Version 10 Compatibility Functions</title>
+<para>
+You can use the X Version 10 compatibility functions to:
+<itemizedlist>
+ <listitem>
+ <para>
+Draw and fill polygons and curves
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Associate user data with a value
+ </para>
+ </listitem>
+</itemizedlist>
+</para>
+<sect2 id="Drawing_and_Filling_Polygons_and_Curves">
+<title>Drawing and Filling Polygons and Curves</title>
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to draw or fill
+arbitrary polygons or curves.
+These functions are provided mainly for compatibility with X Version 10
+and have no server support.
+That is, they call other Xlib functions, not the server directly.
+Thus, if you just have straight lines to draw, using
+<function>XDrawLines</function>
+<indexterm><primary>XDrawLines</primary></indexterm>
+or
+<function>XDrawSegments</function>
+<indexterm><primary>XDrawSegments</primary></indexterm>
+is much faster.
+</para>
+<para>
+<!-- .LP -->
+The functions discussed here provide all the functionality of the
+X Version 10 functions
+<function>XDraw</function>,
+<indexterm ><primary>X10 compatibility</primary><secondary>XDraw</secondary></indexterm>
+<function>XDrawFilled</function>,
+<indexterm><primary>X10 compatibility</primary><secondary>XDrawFilled</secondary></indexterm>
+<function>XDrawPatterned</function>,
+<indexterm ><primary>X10 compatibility</primary><secondary>XDrawPatterned</secondary></indexterm>
+<function>XDrawDashed</function>,
+<indexterm><primary>X10 compatibility</primary><secondary>XDrawDashed</secondary></indexterm>
+and
+<function>XDrawTiled</function>.
+<indexterm><primary>X10 compatibility</primary><secondary>XDrawTiled</secondary></indexterm>
+They are as compatible as possible given X Version 11's new line-drawing
+functions.
+One thing to note, however, is that
+<function>VertexDrawLastPoint</function>
+is no longer supported.
+Also, the error status returned is the opposite of what it was under
+X Version 10 (this is the X Version 11 standard error status).
+<function>XAppendVertex</function>
+and
+<function>XClearVertexFlag</function>
+from X Version 10 also are not supported.
+</para>
+<para>
+<!-- .LP -->
+Just how the graphics context you use is set up actually
+determines whether you get dashes or not, and so on.
+Lines are properly joined if they connect and include
+the closing of a closed figure (see
+<function>XDrawLines</function>).
+The functions discussed here fail (return zero) only if they run out of memory
+or are passed a
+<structname>Vertex</structname>
+list that has a
+<structname>Vertex</structname>
+with
+<symbol>VertexStartClosed</symbol>
+set that is not followed by a
+<structname>Vertex</structname>
+with
+<symbol>VertexEndClosed</symbol>
+set.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To achieve the effects of the X Version 10
+<function>XDraw</function>,
+<indexterm ><primary>X10 compatibility</primary><secondary>XDraw</secondary></indexterm>
+<function>XDrawDashed</function>,
+<indexterm><primary>X10 compatibility</primary><secondary>XDrawDashed</secondary></indexterm>
+and
+<function>XDrawPatterned</function>,
+<indexterm ><primary>X10 compatibility</primary><secondary>XDrawPatterned</secondary></indexterm>
+use
+<function>XDraw</function>.
+</para>
+
+<para>
+#include &lt;X11/X10.h&gt;
+</para>
+
+<funcsynopsis id='xdraw'>
+<funcprototype>
+ <funcdef>Status <function>XDraw</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>Vertex<parameter> *vlist</parameter></paramdef>
+ <paramdef>int<parameter> vcount</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>vlist</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a pointer to the list of vertices that indicate what to draw.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>vcount</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies how many vertices are in vlist.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDraw</function>
+function draws an arbitrary polygon or curve.
+The figure drawn is defined by the specified list of vertices (vlist).
+The points are connected by lines as specified in the flags in the
+vertex structure.
+</para>
+<para>
+<!-- .LP -->
+Each Vertex, as defined in
+<filename class="headerfile">&lt;X11/X10.h&gt;</filename>,
+<indexterm type="file"><primary><filename class="headerfile">X11/X10.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/X10.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/X10.h&gt;</filename></secondary></indexterm>
+is a structure with the following members:
+<indexterm significance="preferred"><primary>Vertex</primary></indexterm>
+<synopsis>
+typedef struct _Vertex {
+ short x,y;
+ unsigned short flags;
+} Vertex;
+</synopsis>
+The x and y members are the coordinates of the vertex
+that are relative to either the upper left inside corner of the drawable
+(if
+<symbol>VertexRelative</symbol>
+is zero) or the previous vertex (if
+<symbol>VertexRelative</symbol>
+is one).
+</para>
+<para>
+<!-- .LP -->
+The flags, as defined in
+<filename class="headerfile">&lt;X11/X10.h&gt;</filename>,
+<indexterm type="file"><primary><filename class="headerfile">X11/X10.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/X10.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/X10.h&gt;</filename></secondary></indexterm>
+are as follows:
+<indexterm significance="preferred"><primary>VertexRelative</primary></indexterm>
+<indexterm significance="preferred"><primary>VertexDontDraw</primary></indexterm>
+<indexterm significance="preferred"><primary>VertexCurved</primary></indexterm>
+<indexterm significance="preferred"><primary>VertexStartClosed</primary></indexterm>
+<indexterm significance="preferred"><primary>VertexEndClosed</primary></indexterm>
+<!-- .sM -->
+
+<synopsis>
+VertexRelative 0x0001 /* else absolute */
+VertexDontDraw 0x0002 /* else draw */
+VertexCurved 0x0004 /* else straight */
+VertexStartClosed 0x0008 /* else not */
+VertexEndClosed 0x0010 /* else not */
+</synopsis>
+
+<itemizedlist>
+ <listitem>
+ <para>
+If
+<symbol>VertexRelative</symbol>
+is not set,
+the coordinates are absolute (that is, relative to the drawable's origin).
+The first vertex must be an absolute vertex.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If
+<symbol>VertexDontDraw</symbol>
+is one,
+no line or curve is drawn from the previous vertex to this one.
+This is analogous to picking up the pen and moving to another place
+before drawing another line.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If
+<symbol>VertexCurved</symbol>
+is one,
+a spline algorithm is used to draw a smooth curve from the previous vertex
+through this one to the next vertex.
+Otherwise, a straight line is drawn from the previous vertex to this one.
+It makes sense to set
+<symbol>VertexCurved</symbol>
+to one only if a previous and next vertex are both defined
+(either explicitly in the array or through the definition of a closed
+curve).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+It is permissible for
+<symbol>VertexDontDraw</symbol>
+bits and
+<symbol>VertexCurved</symbol>
+bits both to be one.
+This is useful if you want to define the previous point for the smooth curve
+but do not want an actual curve drawing to start until this point.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If
+<symbol>VertexStartClosed</symbol>
+is one,
+then this point marks the beginning of a closed curve.
+This vertex must be followed later in the array by another vertex
+whose effective coordinates are identical
+and that has a
+<symbol>VertexEndClosed</symbol>
+bit of one.
+The points in between form a cycle to determine predecessor
+and successor vertices for the spline algorithm.
+ </para>
+ </listitem>
+</itemizedlist>
+</para>
+<para>
+<!-- .LP -->
+This function uses these GC components:
+function, plane-mask, line-width, line-style, cap-style, join-style,
+fill-style, subwindow-mode, clip-x-origin, clip-y-origin, and
+clip-mask.
+It also uses these GC mode-dependent components:
+foreground, background, tile, stipple,
+tile-stipple-x-origin, tile-stipple-y-origin, dash-offset, and dash-list.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To achieve the effects of the X Version 10
+<function>XDrawTiled</function>
+<indexterm><primary>X10 compatibility</primary><secondary>XDrawTiled</secondary></indexterm>
+and
+<function>XDrawFilled</function>,
+<indexterm><primary>X10 compatibility</primary><secondary>XDrawFilled</secondary></indexterm>
+use
+<function>XDrawFilled</function>.
+</para>
+
+<para>#include &lt;X11/X10.h&gt;</para>
+
+<funcsynopsis id='xdrawfilled'>
+<funcprototype>
+ <funcdef>Status <function>XDrawFilled</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>Vertex<parameter> *vlist</parameter></paramdef>
+ <paramdef>int<parameter> vcount</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>vlist</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a pointer to the list of vertices that indicate what to draw.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>vcount</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies how many vertices are in vlist.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDrawFilled</function>
+function draws arbitrary polygons or curves and then fills them.
+</para>
+<para>
+<!-- .LP -->
+This function uses these GC components:
+function, plane-mask, line-width, line-style, cap-style, join-style,
+fill-style, subwindow-mode, clip-x-origin, clip-y-origin, and
+clip-mask.
+It also uses these GC mode-dependent components:
+foreground, background, tile, stipple,
+tile-stipple-x-origin, tile-stipple-y-origin,
+dash-offset, dash-list, fill-style, and fill-rule.
+</para>
+</sect2>
+<sect2 id="Associating_User_Data_with_a_Value">
+<title>Associating User Data with a Value</title>
+<para>
+<!-- .LP -->
+These functions have been superseded by the context management functions
+(see section 16.10).
+It is often necessary to associate arbitrary information with resource IDs.
+Xlib provides the
+<function>XAssocTable</function>
+functions that you can use to make such an association.
+<indexterm><primary>Hash Lookup</primary></indexterm>
+<indexterm><primary>Window</primary><secondary>IDs</secondary></indexterm>
+<indexterm><primary>Resource IDs</primary></indexterm>
+Application programs often need to be able to easily refer to
+their own data structures when an event arrives.
+The
+<function>XAssocTable</function>
+system provides users of the X library with a method
+for associating their own data structures with X resources
+(<type>Pixmap</type>s,
+<type>Font</type>s,
+<type>Window</type>s,
+and so on).
+</para>
+<para>
+<!-- .LP -->
+An
+<function>XAssocTable</function>
+can be used to type X resources.
+For example, the user
+may want to have three or four types of windows,
+each with different properties.
+This can be accomplished by associating each X window ID
+with a pointer to a window property data structure defined by the
+user.
+A generic type has been defined in the X library for resource IDs.
+It is called an XID.
+</para>
+<para>
+<!-- .LP -->
+There are a few guidelines that should be observed when using an
+<function>XAssocTable</function> :
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+All XIDs are relative to the specified display.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Because of the hashing scheme used by the association mechanism,
+the following rules for determining the size of a
+<function>XAssocTable</function>
+should be followed.
+Associations will be made and looked up more
+efficiently if the table size (number of buckets in the hashing
+system) is a power of two and if there are not more than 8 XIDs per
+bucket.
+ </para>
+ </listitem>
+</itemizedlist>
+
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To return a pointer to a new
+<function>XAssocTable</function>,
+use
+<function>XCreateAssocTable</function>.
+<indexterm significance="preferred"><primary>XCreateAssocTable</primary></indexterm>
+<!-- .sM -->
+</para>
+<funcsynopsis id='xcreateassoctable'>
+<funcprototype>
+ <funcdef>XAssocTable *<function>XCreateAssocTable</function></funcdef>
+ <paramdef>int<parameter> size</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>size</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of buckets in the hash system of
+<function>XAssocTable</function>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The size argument specifies the number of buckets in the
+hash system of
+<function>XAssocTable</function>.
+For reasons of efficiency the number of buckets
+should be a power of two.
+Some size suggestions might be: use 32 buckets per 100 objects,
+and a reasonable maximum number of objects per buckets is 8.
+If an error allocating memory for the
+<function>XAssocTable</function>
+occurs,
+a NULL pointer is returned.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create an entry in a given
+<function>XAssocTable</function>,
+use
+<function>XMakeAssoc</function>.
+<indexterm significance="preferred"><primary>XMakeAssoc</primary></indexterm>
+<!-- .sM -->
+</para>
+<funcsynopsis id='xmakeassoc'>
+<funcprototype>
+ <funcdef><function>XMakeAssoc</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XAssocTable<parameter> *table</parameter></paramdef>
+ <paramdef>XID<parameter> x_id</parameter></paramdef>
+ <paramdef>char<parameter> *data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>table</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the assoc table.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x_id</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the X resource ID.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the data to be associated with the X resource ID.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XMakeAssoc</function>
+function inserts data into an
+<function>XAssocTable</function>
+keyed on an XID.
+Data is inserted into the table only once.
+Redundant inserts are ignored.
+The queue in each association bucket is sorted from the lowest XID to
+the highest XID.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain data from a given
+<function>XAssocTable</function>,
+use
+<function>XLookUpAssoc</function>.
+<indexterm significance="preferred"><primary>XLookUpAssoc</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xlookupassoc'>
+<funcprototype>
+ <funcdef>char *<function>XLookUpAssoc</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XAssocTable<parameter> *table</parameter></paramdef>
+ <paramdef>XID<parameter> x_id</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>table</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the assoc table.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x_id</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the X resource ID.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XLookUpAssoc</function>
+function retrieves the data stored in an
+<function>XAssocTable</function>
+by its XID.
+If an appropriately matching XID can be found in the table,
+<function>XLookUpAssoc</function>
+returns the data associated with it.
+If the x_id cannot be found in the table,
+it returns NULL.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To delete an entry from a given
+<function>XAssocTable</function>,
+use
+<function>XDeleteAssoc</function>.
+<indexterm significance="preferred"><primary>XDeleteAssoc</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdeleteassoc'>
+<funcprototype>
+ <funcdef><function>XDeleteAssoc</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XAssocTable<parameter> *table</parameter></paramdef>
+ <paramdef>XID<parameter> x_id</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>table</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the assoc table.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x_id</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the X resource ID.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDeleteAssoc</function>
+function deletes an association in an
+<function>XAssocTable</function>
+keyed on its XID.
+Redundant deletes (and deletes of nonexistent XIDs) are ignored.
+Deleting associations in no way impairs the performance of an
+<function>XAssocTable</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To free the memory associated with a given
+<function>XAssocTable</function>,
+use
+<function>XDestroyAssocTable</function>.
+</para>
+<indexterm significance="preferred"><primary>XDestroyAssocTable</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdestroyassoctable'>
+<funcprototype>
+ <funcdef><function>XDestroyAssocTable</function></funcdef>
+ <paramdef>XAssocTable<parameter> *table</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>table</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the assoc table.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</sect2>
+</sect1>
+</appendix>
diff --git a/libX11/specs/libX11/CH02.xml b/libX11/specs/libX11/CH02.xml
index f4ef1bcd8..901a38503 100644
--- a/libX11/specs/libX11/CH02.xml
+++ b/libX11/specs/libX11/CH02.xml
@@ -66,7 +66,7 @@ To open a connection to the X server that controls a display, use
<function>XOpenDisplay</function>.
<indexterm significance="preferred"><primary>XOpenDisplay</primary></indexterm>
</para>
-<funcsynopsis>
+<funcsynopsis id='xopendisplay'>
<funcprototype>
<funcdef>Display *<function>XOpenDisplay</function></funcdef>
<paramdef>char *<parameter>display_name</parameter></paramdef>
@@ -356,7 +356,7 @@ The names are intended to convey the expected relative intensity of the colors.
<para>
BlackPixel(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xblackpixel'>
<funcprototype>
<funcdef>unsigned long <function>XBlackPixel</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -401,7 +401,7 @@ Both return the black pixel value for the specified screen.
<para>
WhitePixel(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xwhitepixel'>
<funcprototype>
<funcdef>unsigned long <function>XWhitePixel</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -446,7 +446,7 @@ Both return the white pixel value for the specified screen.
<para>
ConnectionNumber(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xconnectionnumber'>
<funcprototype>
<funcdef>int <function>XConnectionNumber</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -483,7 +483,7 @@ this is the file descriptor of the connection.
<para>
DefaultColormap(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdefaultcolormap'>
<funcprototype>
<funcdef>Colormap <function>XDefaultColormap</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -529,7 +529,7 @@ Most routine allocations of color should be made out of this colormap.
<para>
DefaultDepth(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdefaultdepth'>
<funcprototype>
<funcdef>int <function>XDefaultDepth</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -580,7 +580,7 @@ To determine the number of depths that are available on a given screen, use
<para>
DefaultGC(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdefaultgc'>
<funcprototype>
<funcdef>GC <function>XDefaultGC</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -698,7 +698,7 @@ This GC should never be freed.
<para>
DefaultRootWindow(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdefaultrootwindow'>
<funcprototype>
<funcdef>Window <function>XDefaultRootWindow</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -732,7 +732,7 @@ Both return the root window for the default screen.
<para>
DefaultScreenOfDisplay(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdefaultscreenofdisplay'>
<funcprototype>
<funcdef>Screen *<function>XDefaultScreenOfDisplay</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -766,7 +766,7 @@ Both return a pointer to the default screen.
<para>
ScreenOfDisplay(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xscreenofdisplay'>
<funcprototype>
<funcdef>Screen *<function>XScreenOfDisplay</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -811,7 +811,7 @@ Both return a pointer to the indicated screen.
<para>
DefaultScreen(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdefaultscreen'>
<funcprototype>
<funcdef>int <function>XDefaultScreen</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -849,7 +849,7 @@ in applications that will use only a single screen.
<para>
DefaultVisual(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdefaultvisual'>
<funcprototype>
<funcdef>Visual *<function>XDefaultVisual</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -896,7 +896,7 @@ see section 3.1.
<para>
DisplayCells(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdisplaycells'>
<funcprototype>
<funcdef>int <function>XDisplayCells</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -941,7 +941,7 @@ Both return the number of entries in the default colormap.
<para>
DisplayPlanes(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdisplayplanes'>
<funcprototype>
<funcdef>int <function>XDisplayPlanes</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -988,7 +988,7 @@ see the glossary.
<para>
DisplayString(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdisplaystring'>
<funcprototype>
<funcdef>char *<function>XDisplayString</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1032,7 +1032,7 @@ child process as well as for printing error messages.
<para>
LastKnownRequestProcessed(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xlastknownrequestprocessed'>
<funcprototype>
<funcdef>unsigned long <function>XLastKnownRequestProcessed</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1175,7 +1175,7 @@ are received.
<para>
NextRequest(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xnextrequest'>
<funcprototype>
<funcdef>unsigned long <function>XNextRequest</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1211,7 +1211,7 @@ Serial numbers are maintained separately for each display connection.
<para>
ProtocolVersion(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xprotocolversion'>
<funcprototype>
<funcdef>int <function>XProtocolVersion</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1246,7 +1246,7 @@ the connected display.
<para>
ProtocolRevision(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xprotocolrevision'>
<funcprototype>
<funcdef>int <function>XProtocolRevision</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1280,7 +1280,7 @@ Both return the minor protocol revision number of the X server.
<para>
QLength(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xqlength'>
<funcprototype>
<funcdef>int <function>XQLength</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1317,7 +1317,7 @@ the queue yet (see
<para>
RootWindow(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xrootwindow'>
<funcprototype>
<funcdef>Window <function>XRootWindow</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1366,7 +1366,7 @@ and for creating top-level windows.
<para>
ScreenCount(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xscreencount'>
<funcprototype>
<funcdef>int <function>XScreenCount</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1400,7 +1400,7 @@ Both return the number of available screens.
<para>
ServerVendor(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xservervendor'>
<funcprototype>
<funcdef>char *<function>XServerVendor</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1438,7 +1438,7 @@ Otherwise, the contents of the string are implementation-dependent.
<para>
VendorRelease(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xvendorrelease'>
<funcprototype>
<funcdef>int <function>XVendorRelease</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1511,7 +1511,7 @@ To obtain the pixmap format information for a given display, use
<para>
ImageByteOrder(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='ximagebyteorder'>
<funcprototype>
<funcdef>int <function>XImageByteOrder</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1614,7 +1614,7 @@ or
<para>
BitmapUnit(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xbitmapunit'>
<funcprototype>
<funcdef>int <function>XBitmapUnit</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1649,7 +1649,7 @@ The scanline is calculated in multiples of this value.
<para>
BitmapBitOrder(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xbitmpabitorder'>
<funcprototype>
<funcdef>int <function>XBitmapBitOrder</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1689,7 +1689,7 @@ or
<para>
BitmapPad(<emphasis remap='I'>display</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xbitmappad'>
<funcprototype>
<funcdef>int <function>XBitmapPad</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1724,7 +1724,7 @@ by this macro or function.
<para>
DisplayHeight(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdisplayheight'>
<funcprototype>
<funcdef>int <function>XDisplayHeight</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1770,7 +1770,7 @@ in pixels.
<para>
DisplayHeightMM(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdisplayheightmm'>
<funcprototype>
<funcdef>int <function>XDisplayHeightMM</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1815,7 +1815,7 @@ Both return the height of the specified screen in millimeters.
<para>
DisplayWidth(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdisplaywidth'>
<funcprototype>
<funcdef>int <function>XDisplayWidth</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1860,7 +1860,7 @@ Both return the width of the screen in pixels.
<para>
DisplayWidthMM(<emphasis remap='I'>display</emphasis>, <emphasis remap='I'>screen_number</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdisplaywidthmm'>
<funcprototype>
<funcdef>int <function>XDisplayWidthMM</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1919,7 +1919,7 @@ structure.
<para>
BlackPixelOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xblackpixelofscreen'>
<funcprototype>
<funcdef>unsigned long <function>XBlackPixelOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -1955,7 +1955,7 @@ Both return the black pixel value of the specified screen.
<para>
WhitePixelOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xwhitepixelofscreen'>
<funcprototype>
<funcdef>unsigned long <function>XWhitePixelOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -1991,7 +1991,7 @@ Both return the white pixel value of the specified screen.
<para>
CellsOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xcellsofscreen'>
<funcprototype>
<funcdef>int <function>XCellsOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2028,7 +2028,7 @@ of the specified screen.
<para>
DefaultColormapOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdefaultcolormapofscreen'>
<funcprototype>
<funcdef>Colormap <function>XDefaultColormapOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2064,7 +2064,7 @@ Both return the default colormap of the specified screen.
<para>
DefaultDepthOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdefaultdepthofscreen'>
<funcprototype>
<funcdef>int <function>XDefaultDepthOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2100,7 +2100,7 @@ Both return the depth of the root window.
<para>
DefaultGCOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdefaultgcofscreen'>
<funcprototype>
<funcdef>GC <function>XDefaultGCOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2138,7 +2138,7 @@ The GC must never be freed.
<para>
DefaultVisualOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdefaultvisualofscreen'>
<funcprototype>
<funcdef>Visual *<function>XDefaultVisualOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2176,7 +2176,7 @@ see section 3.1.
<para>
DoesBackingStore(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdoesbackingstore'>
<funcprototype>
<funcdef>int <function>XDoesBackingStore</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2219,7 +2219,7 @@ or
<para>
DoesSaveUnders(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdoessaveunders'>
<funcprototype>
<funcdef>Bool <function>XDoesSaveUnders</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2262,7 +2262,7 @@ the screen does not support save unders (see section 3.2.5).
<para>
DisplayOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xdisplayofscreen'>
<funcprototype>
<funcdef>Display *<function>XDisplayOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2299,7 +2299,7 @@ Both return the display of the specified screen.
<para>
EventMaskOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xeventmaskofscreen'>
<funcprototype>
<funcdef>long <function>XEventMaskOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2372,7 +2372,7 @@ at connection setup time.
<para>
WidthOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xwidthofscreen'>
<funcprototype>
<funcdef>int <function>XWidthOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2408,7 +2408,7 @@ Both return the width of the specified screen in pixels.
<para>
HeightOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xheightofscreen'>
<funcprototype>
<funcdef>int <function>XHeightOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2444,7 +2444,7 @@ Both return the height of the specified screen in pixels.
<para>
WidthMMOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xwidthmmofscreen'>
<funcprototype>
<funcdef>int <function>XWidthMMOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2480,7 +2480,7 @@ Both return the width of the specified screen in millimeters.
<para>
HeightMMOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xheightmmofscreen'>
<funcprototype>
<funcdef>int <function>XHeightMMOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2516,7 +2516,7 @@ Both return the height of the specified screen in millimeters.
<para>
MaxCmapsOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xmaxcmapsofscreen'>
<funcprototype>
<funcdef>int <function>XMaxCmapsOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2553,7 +2553,7 @@ by the specified screen (see section 9.3).
<para>
MinCmapsOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xmincmapsofscreen'>
<funcprototype>
<funcdef>int <function>XMinCmapsOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2590,7 +2590,7 @@ by the specified screen (see section 9.3).
<para>
PlanesOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xplanesofscreen'>
<funcprototype>
<funcdef>int <function>XPlanesOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2626,7 +2626,7 @@ Both return the depth of the root window.
<para>
RootWindowOfScreen(<emphasis remap='I'>screen</emphasis>)
</para>
-<funcsynopsis>
+<funcsynopsis id='xrootwindowofscreen'>
<funcprototype>
<funcdef>Window <function>XRootWindowOfScreen</function></funcdef>
<paramdef>Screen<parameter> *screen</parameter></paramdef>
@@ -2670,7 +2670,7 @@ protocol request, use
<indexterm significance="preferred"><primary>XNoOp</primary></indexterm>
<!-- .sM -->
</para>
-<funcsynopsis>
+<funcsynopsis id='xnoop'>
<funcprototype>
<funcdef><function>XNoOp</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -2708,7 +2708,7 @@ To free in-memory data that was created by an Xlib function, use
<indexterm significance="preferred"><primary>XFree</primary></indexterm>
<!-- .sM -->
</para>
-<funcsynopsis>
+<funcsynopsis id='xfree'>
<funcprototype>
<funcdef>XFree</funcdef>
<paramdef>void<parameter> *data</parameter></paramdef>
@@ -2754,7 +2754,7 @@ To close a display or disconnect from the X server, use
<!-- .LP -->
<!-- .sM -->
</para>
-<funcsynopsis>
+<funcsynopsis id='xclosedisplay'>
<funcprototype>
<funcdef>XCloseDisplay</funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -2822,7 +2822,7 @@ To change a client's close-down mode, use
<indexterm significance="preferred"><primary>XSetCloseDownMode</primary></indexterm>
<!-- .sM -->
</para>
-<funcsynopsis>
+<funcsynopsis id='xsetclosedownmode'>
<funcprototype>
<funcdef>XSetCloseDownMode</funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -3107,7 +3107,7 @@ To lock a display across several Xlib calls, use
<indexterm significance="preferred"><primary>XLockDisplay</primary></indexterm>
<!-- .sM -->
</para>
-<funcsynopsis>
+<funcsynopsis id='xlockdisplay'>
<funcprototype>
<funcdef>XLockDisplay</funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -3152,7 +3152,7 @@ To unlock a display, use
<indexterm significance="preferred"><primary>XUnlockDisplay</primary></indexterm>
<!-- .sM -->
</para>
-<funcsynopsis>
+<funcsynopsis id='xunlockdisplay'>
<funcprototype>
<funcdef>XUnlockDisplay</funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -3211,7 +3211,7 @@ facilities.
To track internal connections for a display, use
<function>XAddConnectionWatch</function>.
</para>
-<funcsynopsis>
+<funcsynopsis id='xconnectionwatch'>
<funcprototype>
<funcdef>type void XConnectionWatchProc</funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -3222,7 +3222,7 @@ To track internal connections for a display, use
</funcprototype>
</funcsynopsis>
-<funcsynopsis>
+<funcsynopsis id='xaddconnectionwatch'>
<funcprototype>
<funcdef>Status XAddConnectionWatch</funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -3313,7 +3313,7 @@ To stop tracking internal connections for a display, use
<para>
()
</para>
-<funcsynopsis>
+<funcsynopsis id='xremoveconnectionwatch'>
<funcprototype>
<funcdef>Status <function>XRemoveConnectionWatch</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -3375,7 +3375,7 @@ To process input on an internal connection, use
<para>
()
</para>
-<funcsynopsis>
+<funcsynopsis id='xprocessinternalconnection'>
<funcprototype>
<funcdef>void <function>XProcessInternalConnection</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -3430,7 +3430,7 @@ To obtain all of the current internal connections for a display, use
<para>
()
</para>
-<funcsynopsis>
+<funcsynopsis id='xinternalconnectionnumbers'>
<funcprototype>
<funcdef>Status <function>XInternalConnectionNumbers</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
diff --git a/libX11/specs/libX11/CH03.xml b/libX11/specs/libX11/CH03.xml
index 645960797..9cbacd83b 100644
--- a/libX11/specs/libX11/CH03.xml
+++ b/libX11/specs/libX11/CH03.xml
@@ -1,4164 +1,4164 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<chapter id="window_functions"><title>Window Functions</title>
-<sect1 id="Visual_Types">
-<title>Visual Types</title>
-<!-- .XS -->
-<!-- (SN Visual Types -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>Visual Type</primary></indexterm>
-On some display hardware,
-it may be possible to deal with color resources in more than one way.
-For example, you may be able to deal with a screen of either 12-bit depth
-with arbitrary mapping of pixel to color (pseudo-color) or 24-bit depth
-with 8 bits of the pixel dedicated to each of red, green, and blue.
-These different ways of dealing with the visual aspects of the screen
-are called visuals.
-For each screen of the display, there may be a list of valid visual types
-supported at different depths of the screen.
-Because default windows and visual types are defined for each screen,
-most simple applications need not deal with this complexity.
-Xlib provides macros and functions that return the default root window,
-the default depth of the default root window, and the default visual type
-(see sections 2.2.1 and 16.7).
-</para>
-<para>
-<!-- .LP -->
-Xlib uses an opaque
-<structname>Visual</structname>
-<indexterm significance="preferred"><primary>Visual</primary></indexterm>
-structure that contains information about the possible color mapping.
-The visual utility functions (see section 16.7) use an
-<structname>XVisualInfo</structname>
-structure to return this information to an application.
-The members of this structure pertinent to this discussion are class, red_mask,
-green_mask, blue_mask, bits_per_rgb, and colormap_size.
-The class member specifies one of the possible visual classes of the screen
-and can be
-<indexterm><primary>Visual Classes</primary><secondary>StaticGray</secondary></indexterm>
-<indexterm><primary>Visual Classes</primary><secondary>StaticColor</secondary></indexterm>
-<indexterm><primary>Visual Classes</primary><secondary>TrueColor</secondary></indexterm>
-<indexterm><primary>Visual Classes</primary><secondary>StaticColor</secondary></indexterm>
-<indexterm><primary>Visual Classes</primary><secondary>GrayScale</secondary></indexterm>
-<indexterm><primary>Visual Classes</primary><secondary>PseudoColor</secondary></indexterm>
-<symbol>StaticGray</symbol>,
-<symbol>StaticColor</symbol>,
-<symbol>TrueColor</symbol>,
-<symbol>GrayScale</symbol>,
-<symbol>PseudoColor</symbol>,
-or
-<symbol>DirectColor</symbol>.
-</para>
-<para>
-<!-- .LP -->
-The following concepts may serve to make the explanation of
-visual types clearer.
-The screen can be color or grayscale,
-can have a colormap that is writable or read-only,
-and can also have a colormap whose indices are decomposed into separate
-<acronym>RGB</acronym> pieces, provided one is not on a grayscale screen.
-This leads to the following diagram:
-</para>
-
-<literallayout class="monospaced">
- Color Gray-Scale
- R/O R/W R/O R/W
-----------------------------------------------
- Undecomposed Static Pseudo Static Gray
- Colormap Color Color Gray Scale
-
- Decomposed True Direct
- Colormap Color Color
-----------------------------------------------
-</literallayout>
-
-<para>
-<!-- .LP -->
-Conceptually,
-as each pixel is read out of video memory for display on the screen,
-it goes through a look-up stage by indexing into a colormap.
-Colormaps can be manipulated arbitrarily on some hardware,
-in limited ways on other hardware, and not at all on other hardware.
-The visual types affect the colormap and
-the <acronym>RGB</acronym> values in the following ways:
-</para>
-<para>
-<!-- .LP -->
-</para>
-<itemizedlist>
- <listitem>
- <para>
-For
-<symbol>PseudoColor</symbol>,
-a pixel value indexes a colormap to produce
-independent <acronym>RGB</acronym> values, and the <acronym>RGB</acronym> values can be changed dynamically.
- </para>
- </listitem>
- <listitem>
- <para>
-<symbol>GrayScale</symbol>
-is treated the same way as
-<symbol>PseudoColor</symbol>
-except that the primary that drives the screen is undefined.
-Thus, the client should always store the
-same value for red, green, and blue in the colormaps.
- </para>
- </listitem>
- <listitem>
- <para>
-For
-<symbol>DirectColor</symbol>,
-a pixel value is decomposed into separate <acronym>RGB</acronym> subfields, and each
-subfield separately indexes the colormap for the corresponding value.
-The <acronym>RGB</acronym> values can be changed dynamically.
- </para>
- </listitem>
- <listitem>
- <para>
-<symbol>TrueColor</symbol>
-is treated the same way as
-<symbol>DirectColor</symbol>
-except that the colormap has predefined, read-only <acronym>RGB</acronym> values.
-These <acronym>RGB</acronym> values are server dependent but provide linear or near-linear
-ramps in each primary.
- </para>
- </listitem>
- <listitem>
- <para>
-<symbol>StaticColor</symbol>
-is treated the same way as
-<symbol>PseudoColor</symbol>
-except that the colormap has predefined,
-read-only, server-dependent <acronym>RGB</acronym> values.
- </para>
- </listitem>
- <listitem>
- <para>
-<symbol>StaticGray</symbol>
-is treated the same way as
-<symbol>StaticColor</symbol>
-except that the <acronym>RGB</acronym> values are equal for any single pixel
-value, thus resulting in shades of gray.
-<symbol>StaticGray</symbol>
-with a two-entry
-colormap can be thought of as monochrome.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The red_mask, green_mask, and blue_mask members are only defined for
-<symbol>DirectColor</symbol>
-and
-<symbol>TrueColor</symbol>.
-Each has one contiguous set of bits with no
-intersections.
-The bits_per_rgb member specifies the log base 2 of the
-number of distinct color values (individually) of red, green, and blue.
-Actual <acronym>RGB</acronym> values are unsigned 16-bit numbers.
-The colormap_size member defines the number of available colormap entries
-in a newly created colormap.
-For
-<symbol>DirectColor</symbol>
-and
-<symbol>TrueColor</symbol>,
-this is the size of an individual pixel subfield.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the visual ID from a
-<structname>Visual</structname>,
-use
-<function>XVisualIDFromVisual</function>.
-<indexterm significance="preferred"><primary>XVisualIDFromVisual</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>VisualID <function>XVisualIDFromVisual</function></funcdef>
- <paramdef>Visual *<parameter>visual</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>visual</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the visual type.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XVisualIDFromVisual</function>
-function returns the visual ID for the specified visual type.
-</para>
-</sect1>
-<sect1 id="Window_Attributes">
-<title>Window Attributes</title>
-<!-- .XS -->
-<!-- (SN Window Attributes -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Window</primary></indexterm>
-<indexterm><primary>Window</primary><secondary>attributes</secondary></indexterm>
-All
-<symbol>InputOutput</symbol>
-windows have a border width of zero or more pixels, an optional background,
-an event suppression mask (which suppresses propagation of events from
-children), and a property list (see section 4.3).
-The window border and background can be a solid color or a pattern, called
-a tile.
-All windows except the root have a parent and are clipped by their parent.
-If a window is stacked on top of another window, it obscures that other
-window for the purpose of input.
-If a window has a background (almost all do), it obscures the other
-window for purposes of output.
-Attempts to output to the obscured area do nothing,
-and no input events (for example, pointer motion) are generated for the
-obscured area.
-</para>
-<para>
-<!-- .LP -->
-Windows also have associated property lists (see section 4.3).
-</para>
-<para>
-<!-- .LP -->
-Both
-<symbol>InputOutput</symbol>
-and
-<symbol>InputOnly</symbol>
-windows have the following common attributes,
-which are the only attributes of an
-<symbol>InputOnly</symbol>
-window:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-win-gravity
- </para>
- </listitem>
- <listitem>
- <para>
-event-mask
- </para>
- </listitem>
- <listitem>
- <para>
-do-not-propagate-mask
- </para>
- </listitem>
- <listitem>
- <para>
-override-redirect
- </para>
- </listitem>
- <listitem>
- <para>
-cursor
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-If you specify any other attributes for an
-<symbol>InputOnly</symbol>
-window,
-a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<symbol>InputOnly</symbol>
-windows are used for controlling input events in situations where
-<symbol>InputOutput</symbol>
-windows are unnecessary.
-<symbol>InputOnly</symbol>
-windows are invisible; can only be used to control such things as
-cursors, input event generation, and grabbing;
-and cannot be used in any graphics requests.
-Note that
-<symbol>InputOnly</symbol>
-windows cannot have
-<symbol>InputOutput</symbol>
-windows as inferiors.
-</para>
-<para>
-<!-- .LP -->
-Windows have borders of a programmable width and pattern
-as well as a background pattern or tile.
-<indexterm><primary>Tile</primary><secondary>pixmaps</secondary></indexterm>
-Pixel values can be used for solid colors.
-<indexterm><primary>Resource IDs</primary><secondary>freeing</secondary></indexterm>
-<indexterm><primary>Freeing</primary><secondary>resources</secondary></indexterm>
-The background and border pixmaps can be destroyed immediately after
-creating the window if no further explicit references to them
-are to be made.
-<indexterm ><primary>Tile</primary><secondary>mode</secondary></indexterm>
-The pattern can either be relative to the parent
-or absolute.
-If
-<symbol>ParentRelative</symbol>,
-the parent's background is used.
-</para>
-<para>
-<!-- .LP -->
-When windows are first created,
-they are not visible (not mapped) on the screen.
-Any output to a window that is not visible on the screen
-and that does not have backing store will be discarded.
-<indexterm><primary>Window</primary><secondary>mapping</secondary></indexterm>
-An application may wish to create a window long before it is
-mapped to the screen.
-When a window is eventually mapped to the screen
-(using
-<function>XMapWindow</function>),
-<indexterm><primary>XMapWindow</primary></indexterm>
-the X server generates an
-<symbol>Expose</symbol>
-event for the window if backing store has not been maintained.
-</para>
-<para>
-<!-- .LP -->
-A window manager can override your choice of size,
-border width, and position for a top-level window.
-Your program must be prepared to use the actual size and position
-of the top window.
-It is not acceptable for a client application to resize itself
-unless in direct response to a human command to do so.
-Instead, either your program should use the space given to it,
-or if the space is too small for any useful work, your program
-might ask the user to resize the window.
-The border of your top-level window is considered fair game
-for window managers.
-</para>
-<para>
-<!-- .LP -->
-To set an attribute of a window,
-set the appropriate member of the
-<structname>XSetWindowAttributes</structname>
-structure and OR in the corresponding value bitmask in your subsequent calls to
-<function>XCreateWindow</function>
-and
-<function>XChangeWindowAttributes</function>,
-or use one of the other convenience functions that set the appropriate
-attribute.
-The symbols for the value mask bits and the
-<structname>XSetWindowAttributes</structname>
-structure are:
-<!-- .sM -->
-</para>
-<para>
-<!-- .LP -->
-/* Window attribute value mask bits */
-
-
-<literallayout class="monospaced">
-/* Window attribute value mask bits */
-#define CWBackPixmap (1L&lt;&lt;0)
-#define CWBackPixel (1L&lt;&lt;1)
-#define CWBorderPixmap (1L&lt;&lt;2)
-#define CWBorderPixel (1L&lt;&lt;3)
-#define CWBitGravity (1L&lt;&lt;4)
-#define CWWinGravity (1L&lt;&lt;5)
-#define CWBackingStore (1L&lt;&lt;6)
-#define CWBackingPlanes (1L&lt;&lt;7)
-#define CWBackingPixel (1L&lt;&lt;8)
-#define CWOverrideRedirect (1L&lt;&lt;9)
-#define CWSaveUnder (1L&lt;&lt;10)
-#define CWEventMask (1L&lt;&lt;11)
-#define CWDontPropagate (1L&lt;&lt;12)
-#define CWColormap (1L&lt;&lt;13)
-#define CWCursor (1L&lt;&lt;14)
-</literallayout>
-
-<indexterm significance="preferred"><primary>XSetWindowAttributes</primary></indexterm>
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-/* Values */
-
-typedef struct {
- Pixmap background_pixmap; /* background, None, or ParentRelative */
- unsigned long background_pixel; /* background pixel */
- Pixmap border_pixmap; /* border of the window or CopyFromParent */
- unsigned long border_pixel; /* border pixel value */
- int bit_gravity; /* one of bit gravity values */
- int win_gravity; /* one of the window gravity values */
- int backing_store; /* NotUseful, WhenMapped, Always */
- unsigned long backing_planes; /* planes to be preserved if possible */
- unsigned long backing_pixel; /* value to use in restoring planes */
- Bool save_under; /* should bits under be saved? (popups) */
- long event_mask; /* set of events that should be saved */
- long do_not_propagate_mask; /* set of events that should not propagate */
- Bool override_redirect; /* boolean value for override_redirect */
- Colormap colormap; /* color map to be associated with window */
- Cursor cursor; /* cursor to be displayed (or None) */
-} XSetWindowAttributes;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The following lists the defaults for each window attribute and indicates
-whether the attribute is applicable to
-<symbol>InputOutput</symbol>
-and
-<symbol>InputOnly</symbol>
-windows:
-</para>
-<informaltable>
- <tgroup cols='4' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <colspec colname='c4'/>
- <thead>
- <row>
- <entry>Attribute</entry>
- <entry>Default</entry>
- <entry>InputOutput</entry>
- <entry>nputOnly</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry>background-pixmap</entry>
- <entry><symbol>None</symbol></entry>
- <entry>Yes</entry>
- <entry>No</entry>
- </row>
- <row>
- <entry>background-pixel</entry>
- <entry>Undefined</entry>
- <entry>Yes</entry>
- <entry>No</entry>
- </row>
- <row>
- <entry>border-pixmap</entry>
- <entry><symbol>CopyFromParent</symbol></entry>
- <entry>Yes</entry>
- <entry>No</entry>
- </row>
- <row>
- <entry>border-pixel</entry>
- <entry>Undefined</entry>
- <entry>Yes</entry>
- <entry>No</entry>
- </row>
- <row>
- <entry>bit-gravity</entry>
- <entry><symbol>ForgetGravity</symbol></entry>
- <entry>Yes</entry>
- <entry>No</entry>
- </row>
- <row>
- <entry>win-gravity</entry>
- <entry><symbol>NorthWestGravity</symbol></entry>
- <entry>Yes</entry>
- <entry>Yes</entry>
- </row>
- <row>
- <entry>backing-store</entry>
- <entry><symbol>NotUseful</symbol></entry>
- <entry>Yes</entry>
- <entry>No</entry>
- </row>
- <row>
- <entry>backing-planes</entry>
- <entry>All ones</entry>
- <entry>Yes</entry>
- <entry>No</entry>
- </row>
- <row>
- <entry>backing-pixel</entry>
- <entry>zero</entry>
- <entry>Yes</entry>
- <entry>No</entry>
- </row>
- <row>
- <entry>save-under</entry>
- <entry><symbol>False</symbol></entry>
- <entry>Yes</entry>
- <entry>No</entry>
- </row>
- <row>
- <entry>event-mask</entry>
- <entry>empty set</entry>
- <entry>Yes</entry>
- <entry>Yes</entry>
- </row>
- <row>
- <entry>do-not-propagate-mask</entry>
- <entry>empty set</entry>
- <entry>Yes</entry>
- <entry>Yes</entry>
- </row>
- <row>
- <entry>override-redirect</entry>
- <entry><symbol>False</symbol></entry>
- <entry>Yes</entry>
- <entry>Yes</entry>
- </row>
- <row>
- <entry>colormap</entry>
- <entry><symbol>CopyFromParent</symbol></entry>
- <entry>Yes</entry>
- <entry>No</entry>
- </row>
- <row>
- <entry>cursor</entry>
- <entry><symbol>None</symbol></entry>
- <entry>Yes</entry>
- <entry>Yes</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<sect2 id="Background_Attribute">
-<title>Background Attribute</title>
-<!-- .XS -->
-<!-- (SN Background Attribute -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Only
-<symbol>InputOutput</symbol>
-windows can have a background.
-You can set the background of an
-<symbol>InputOutput</symbol>
-window by using a pixel or a pixmap.
-</para>
-<para>
-<!-- .LP -->
-The background-pixmap attribute of a window specifies the pixmap to be used for
-a window's background.
-This pixmap can be of any size, although some sizes may be faster than others.
-The background-pixel attribute of a window specifies a pixel value used to paint
-a window's background in a single color.
-</para>
-<para>
-<!-- .LP -->
-You can set the background-pixmap to a pixmap,
-<symbol>None</symbol>
-(default), or
-<symbol>ParentRelative</symbol>.
-You can set the background-pixel of a window to any pixel value (no default).
-If you specify a background-pixel,
-it overrides either the default background-pixmap
-or any value you may have set in the background-pixmap.
-A pixmap of an undefined size that is filled with the background-pixel is used
-for the background.
-Range checking is not performed on the background pixel;
-it simply is truncated to the appropriate number of bits.
-</para>
-<para>
-<!-- .LP -->
-If you set the background-pixmap,
-it overrides the default.
-The background-pixmap and the window must have the same depth,
-or a
-<errorname>BadMatch</errorname>
-error results.
-If you set background-pixmap to
-<symbol>None</symbol>,
-the window has no defined background.
-If you set the background-pixmap to
-<symbol>ParentRelative</symbol>:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The parent window's background-pixmap is used.
-The child window, however, must have the same depth as
-its parent,
-or a
-<errorname>BadMatch</errorname>
-error results.
- </para>
- </listitem>
- <listitem>
- <para>
-If the parent window has a background-pixmap of
-<symbol>None</symbol>,
-the window also has a background-pixmap of
-<symbol>None</symbol>.
- </para>
- </listitem>
- <listitem>
- <para>
-A copy of the parent window's background-pixmap is not made.
-The parent's background-pixmap is examined each time the child window's
-background-pixmap is required.
- </para>
- </listitem>
- <listitem>
- <para>
-The background tile origin always aligns with the parent window's
-background tile origin.
-If the background-pixmap is not
-<symbol>ParentRelative</symbol>,
-the background tile origin is the child window's origin.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Setting a new background, whether by setting background-pixmap or
-background-pixel, overrides any previous background.
-The background-pixmap can be freed immediately if no further explicit reference
-is made to it (the X server will keep a copy to use when needed).
-If you later draw into the pixmap used for the background,
-what happens is undefined because the
-X implementation is free to make a copy of the pixmap or
-to use the same pixmap.
-</para>
-<para>
-<!-- .LP -->
-When no valid contents are available for regions of a window
-and either the regions are visible or the server is maintaining backing store,
-the server automatically tiles the regions with the window's background
-unless the window has a background of
-<symbol>None</symbol>.
-If the background is
-<symbol>None</symbol>,
-the previous screen contents from other windows of the same depth as the window
-are simply left in place as long as the contents come from the parent of the
-window or an inferior of the parent.
-Otherwise, the initial contents of the exposed regions are undefined.
-<symbol>Expose</symbol>
-events are then generated for the regions, even if the background-pixmap
-is
-<symbol>None</symbol>
-(see section 10.9).
-</para>
-</sect2>
-<sect2 id="Border_Attribute">
-<title>Border Attribute</title>
-<!-- .XS -->
-<!-- (SN Border Attribute -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Only
-<symbol>InputOutput</symbol>
-windows can have a border.
-You can set the border of an
-<symbol>InputOutput</symbol>
-window by using a pixel or a pixmap.
-</para>
-<para>
-<!-- .LP -->
-The border-pixmap attribute of a window specifies the pixmap to be used
-for a window's border.
-The border-pixel attribute of a window specifies a pixmap of undefined size
-filled with that pixel be used for a window's border.
-Range checking is not performed on the background pixel;
-it simply is truncated to the appropriate number of bits.
-The border tile origin is always the same as the background tile origin.
-</para>
-<para>
-<!-- .LP -->
-You can also set the border-pixmap to a pixmap of any size (some may be faster
-than others) or to
-<symbol>CopyFromParent</symbol>
-(default).
-You can set the border-pixel to any pixel value (no default).
-</para>
-<para>
-<!-- .LP -->
-If you set a border-pixmap,
-it overrides the default.
-The border-pixmap and the window must have the same depth,
-or a
-<errorname>BadMatch</errorname>
-error results.
-If you set the border-pixmap to
-<symbol>CopyFromParent</symbol>,
-the parent window's border-pixmap is copied.
-Subsequent changes to the parent window's border attribute do not affect
-the child window.
-However, the child window must have the same depth as the parent window,
-or a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-The border-pixmap can be freed immediately if no further explicit reference
-is made to it.
-If you later draw into the pixmap used for the border,
-what happens is undefined because the
-X implementation is free either to make a copy of the pixmap or
-to use the same pixmap.
-If you specify a border-pixel,
-it overrides either the default border-pixmap
-or any value you may have set in the border-pixmap.
-All pixels in the window's border will be set to the border-pixel.
-Setting a new border, whether by setting border-pixel or by setting
-border-pixmap, overrides any previous border.
-</para>
-<para>
-<!-- .LP -->
-Output to a window is always clipped to the inside of the window.
-Therefore, graphics operations never affect the window border.
-</para>
-</sect2>
-<sect2 id="Gravity_Attributes">
-<title>Gravity Attributes</title>
-<!-- .XS -->
-<!-- (SN Gravity Attributes -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The bit gravity of a window defines which region of the window should be
-retained when an
-<symbol>InputOutput</symbol>
-window is resized.
-The default value for the bit-gravity attribute is
-<symbol>ForgetGravity</symbol>.
-The window gravity of a window allows you to define how the
-<symbol>InputOutput</symbol>
-or
-<symbol>InputOnly</symbol>
-window should be repositioned if its parent is resized.
-The default value for the win-gravity attribute is
-<symbol>NorthWestGravity</symbol>.
-</para>
-<para>
-<!-- .LP -->
-If the inside width or height of a window is not changed
-and if the window is moved or its border is changed,
-then the contents of the window are not lost but move with the window.
-Changing the inside width or height of the window causes its contents to be
-moved or lost (depending on the bit-gravity of the window) and causes
-children to be reconfigured (depending on their win-gravity).
-For a
-change of width and height, the (x, y) pairs are defined:
-</para>
-<para>
-<!-- .LP -->
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <thead>
- <row>
- <entry>Gravity Direction</entry>
- <entry>Coordinates</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry><symbol>NorthWestGravity</symbol></entry>
- <entry>(0, 0)</entry>
- </row>
- <row>
- <entry><symbol>NorthGravity</symbol></entry>
- <entry>(Width/2, 0)</entry>
- </row>
- <row>
- <entry><symbol>NorthEastGravity</symbol></entry>
- <entry>(Width, 0)</entry>
- </row>
- <row>
- <entry><symbol>WestGravity</symbol></entry>
- <entry>(0, Height/2)</entry>
- </row>
- <row>
- <entry><symbol>CenterGravity</symbol></entry>
- <entry>(Width/2, Height/2)</entry>
- </row>
- <row>
- <entry><symbol>EastGravity</symbol></entry>
- <entry>(Width, Height/2)</entry>
- </row>
- <row>
- <entry><symbol>SouthWestGravity</symbol></entry>
- <entry>(0, Height)</entry>
- </row>
- <row>
- <entry><symbol>SouthGravity</symbol></entry>
- <entry>(Width/2, Height)</entry>
- </row>
- <row>
- <entry><symbol>SouthEastGravity</symbol></entry>
- <entry>(Width, Height)</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-</para>
-<para>
-<!-- .LP -->
-When a window with one of these bit-gravity values is resized,
-the corresponding pair
-defines the change in position of each pixel in the window.
-When a window with one of these win-gravities has its parent window resized,
-the corresponding pair defines the change in position of the window
-within the parent.
-When a window is so repositioned, a
-<symbol>GravityNotify</symbol>
-event is generated (see section 10.10.5).
-</para>
-<para>
-<!-- .LP -->
-A bit-gravity of
-<symbol>StaticGravity</symbol>
-indicates that the contents or origin should not move relative to the
-origin of the root window.
-If the change in size of the window is coupled with a change in position (x, y),
-then for bit-gravity the change in position of each pixel is (&minus;x, &minus;y), and for
-win-gravity the change in position of a child when its parent is so resized is
-(&minus;x, &minus;y).
-Note that
-<symbol>StaticGravity</symbol>
-still only takes effect when the width or height of the window is changed,
-not when the window is moved.
-</para>
-<para>
-<!-- .LP -->
-A bit-gravity of
-<symbol>ForgetGravity</symbol>
-indicates that the window's contents are always discarded after a size change,
-even if a backing store or save under has been requested.
-The window is tiled with its background
-and zero or more
-<symbol>Expose</symbol>
-events are generated.
-If no background is defined, the existing screen contents are not
-altered.
-Some X servers may also ignore the specified bit-gravity and
-always generate
-<symbol>Expose</symbol>
-events.
-</para>
-<para>
-<!-- .LP -->
-The contents and borders of inferiors are not affected by their parent's
-bit-gravity.
-A server is permitted to ignore the specified bit-gravity and use
-<symbol>Forget</symbol>
-instead.
-</para>
-<para>
-<!-- .LP -->
-A win-gravity of
-<symbol>UnmapGravity</symbol>
-is like
-<symbol>NorthWestGravity</symbol>
-(the window is not moved),
-except the child is also
-unmapped when the parent is resized,
-and an
-<symbol>UnmapNotify</symbol>
-event is
-generated.
-</para>
-</sect2>
-<sect2 id="Backing_Store_Attribute">
-<title>Backing Store Attribute</title>
-<!-- .XS -->
-<!-- (SN Backing Store Attribute -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Some implementations of the X server may choose to maintain the contents of
-<symbol>InputOutput</symbol>
-windows.
-If the X server maintains the contents of a window,
-the off-screen saved pixels
-are known as backing store.
-The backing store advises the X server on what to do
-with the contents of a window.
-The backing-store attribute can be set to
-<symbol>NotUseful</symbol>
-(default),
-<symbol>WhenMapped</symbol>,
-or
-<symbol>Always</symbol>.
-</para>
-<para>
-<!-- .LP -->
-A backing-store attribute of
-<symbol>NotUseful</symbol>
-advises the X server that
-maintaining contents is unnecessary,
-although some X implementations may
-still choose to maintain contents and, therefore, not generate
-<symbol>Expose</symbol>
-events.
-A backing-store attribute of
-<symbol>WhenMapped</symbol>
-advises the X server that maintaining contents of
-obscured regions when the window is mapped would be beneficial.
-In this case,
-the server may generate an
-<symbol>Expose</symbol>
-event when the window is created.
-A backing-store attribute of
-<symbol>Always</symbol>
-advises the X server that maintaining contents even when
-the window is unmapped would be beneficial.
-Even if the window is larger than its parent,
-this is a request to the X server to maintain complete contents,
-not just the region within the parent window boundaries.
-While the X server maintains the window's contents,
-<symbol>Expose</symbol>
-events normally are not generated,
-but the X server may stop maintaining
-contents at any time.
-</para>
-<para>
-<!-- .LP -->
-When the contents of obscured regions of a window are being maintained,
-regions obscured by noninferior windows are included in the destination
-of graphics requests (and source, when the window is the source).
-However, regions obscured by inferior windows are not included.
-</para>
-</sect2>
-<sect2 id="Save_Under_Flag">
-<title>Save Under Flag</title>
-<!-- .XS -->
-<!-- (SN Save Under Flag -->
-<!-- .XE -->
-<indexterm><primary>Save Unders</primary></indexterm>
-<para>
-<!-- .LP -->
-Some server implementations may preserve contents of
-<symbol>InputOutput</symbol>
-windows under other
-<symbol>InputOutput</symbol>
-windows.
-This is not the same as preserving the contents of a window for you.
-You may get better visual
-appeal if transient windows (for example, pop-up menus) request that the system
-preserve the screen contents under them,
-so the temporarily obscured applications do not have to repaint.
-</para>
-<para>
-<!-- .LP -->
-You can set the save-under flag to
-<symbol>True</symbol>
-or
-<symbol>False</symbol>
-(default).
-If save-under is
-<symbol>True</symbol>,
-the X server is advised that, when this window is mapped,
-saving the contents of windows it obscures would be beneficial.
-</para>
-</sect2>
-<sect2 id="Backing_Planes_and_Backing_Pixel_Attributes">
-<title>Backing Planes and Backing Pixel Attributes</title>
-<!-- .XS -->
-<!-- (SN Backing Planes and Backing Pixel Attributes -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-You can set backing planes to indicate (with bits set to 1)
-which bit planes of an
-<symbol>InputOutput</symbol>
-window hold dynamic data that must be preserved in backing store
-and during save unders.
-The default value for the backing-planes attribute is all bits set to 1.
-You can set backing pixel to specify what bits to use in planes not
-covered by backing planes.
-The default value for the backing-pixel attribute is all bits set to 0.
-The X server is free to save only the specified bit planes in the backing store
-or the save under and is free to regenerate the remaining planes with
-the specified pixel value.
-Any extraneous bits in these values (that is, those bits beyond
-the specified depth of the window) may be simply ignored.
-If you request backing store or save unders,
-you should use these members to minimize the amount of off-screen memory
-required to store your window.
-</para>
-</sect2>
-<sect2 id="Event_Mask_and_Do_Not_Propagate_Mask_Attributes">
-<title>Event Mask and Do Not Propagate Mask Attributes</title>
-<!-- .XS -->
-<!-- (SN Event Mask and Do Not Propagate Mask Attributes -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The event mask defines which events the client is interested in for this
-<symbol>InputOutput</symbol>
-or
-<symbol>InputOnly</symbol>
-window (or, for some event types, inferiors of this window).
-The event mask is the bitwise inclusive OR of zero or more of the
-valid event mask bits.
-You can specify that no maskable events are reported by setting
-<symbol>NoEventMask</symbol>
-(default).
-</para>
-<para>
-<!-- .LP -->
-The do-not-propagate-mask attribute
-defines which events should not be propagated to
-ancestor windows when no client has the event type selected in this
-<symbol>InputOutput</symbol>
-or
-<symbol>InputOnly</symbol>
-window.
-The do-not-propagate-mask is the bitwise inclusive OR of zero or more
-of the following masks:
-<symbol>KeyPress</symbol>,
-<symbol>KeyRelease</symbol>,
-<symbol>ButtonPress</symbol>,
-<symbol>ButtonRelease</symbol>,
-<symbol>PointerMotion</symbol>,
-<symbol>Button1Motion</symbol>,
-<symbol>Button2Motion</symbol>,
-<symbol>Button3Motion</symbol>,
-<symbol>Button4Motion</symbol>,
-<symbol>Button5Motion</symbol>,
-and
-<symbol>ButtonMotion</symbol>.
-You can specify that all events are propagated by setting
-<symbol>NoEventMask</symbol>
-(default).
-</para>
-</sect2>
-<sect2 id="Override_Redirect_Flag">
-<title>Override Redirect Flag</title>
-<!-- .XS -->
-<!-- (SN Override Redirect Flag -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To control window placement or to add decoration,
-a window manager often needs to intercept (redirect) any map or configure
-request.
-Pop-up windows, however, often need to be mapped without a window manager
-getting in the way.
-To control whether an
-<symbol>InputOutput</symbol>
-or
-<symbol>InputOnly</symbol>
-window is to ignore these structure control facilities,
-use the override-redirect flag.
-</para>
-<para>
-<!-- .LP -->
-The override-redirect flag specifies whether map and configure requests
-on this window should override a
-<symbol>SubstructureRedirectMask</symbol>
-on the parent.
-You can set the override-redirect flag to
-<symbol>True</symbol>
-or
-<symbol>False</symbol>
-(default).
-Window managers use this information to avoid tampering with pop-up windows
-(see also chapter 14).
-</para>
-</sect2>
-<sect2 id="Colormap_Attribute">
-<title>Colormap Attribute</title>
-<!-- .XS -->
-<!-- (SN Colormap Attribute -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The colormap attribute specifies which colormap best reflects the true
-colors of the
-<symbol>InputOutput</symbol>
-window.
-The colormap must have the same visual type as the window,
-or a
-<errorname>BadMatch</errorname>
-error results.
-X servers capable of supporting multiple
-hardware colormaps can use this information,
-and window managers can use it for calls to
-<function>XInstallColormap</function>.
-You can set the colormap attribute to a colormap or to
-<symbol>CopyFromParent</symbol>
-(default).
-</para>
-<para>
-<!-- .LP -->
-If you set the colormap to
-<symbol>CopyFromParent</symbol>,
-the parent window's colormap is copied and used by its child.
-However, the child window must have the same visual type as the parent,
-or a
-<errorname>BadMatch</errorname>
-error results.
-The parent window must not have a colormap of
-<symbol>None</symbol>,
-or a
-<errorname>BadMatch</errorname>
-error results.
-The colormap is copied by sharing the colormap object between the child
-and parent, not by making a complete copy of the colormap contents.
-Subsequent changes to the parent window's colormap attribute do
-not affect the child window.
-</para>
-</sect2>
-<sect2 id="Cursor_Attribute">
-<title>Cursor Attribute</title>
-<!-- .XS -->
-<!-- (SN Cursor Attribute -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The cursor attribute specifies which cursor is to be used when the pointer is
-in the
-<symbol>InputOutput</symbol>
-or
-<symbol>InputOnly</symbol>
-window.
-You can set the cursor to a cursor or
-<symbol>None</symbol>
-(default).
-</para>
-<para>
-<!-- .LP -->
-If you set the cursor to
-<symbol>None</symbol>,
-the parent's cursor is used when the
-pointer is in the
-<symbol>InputOutput</symbol>
-or
-<symbol>InputOnly</symbol>
-window, and any change in the parent's cursor will cause an
-immediate change in the displayed cursor.
-By calling
-<function>XFreeCursor</function>,
-the cursor can be freed immediately as long as no further explicit reference
-to it is made.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Creating_Windows">
-<title>Creating Windows</title>
-<!-- .XS -->
-<!-- (SN Creating Windows -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides basic ways for creating windows,
-and toolkits often supply higher-level functions specifically for
-creating and placing top-level windows,
-which are discussed in the appropriate toolkit documentation.
-If you do not use a toolkit, however,
-you must provide some standard information or hints for the window
-manager by using the Xlib inter-client communication functions
-(see chapter 14).
-</para>
-<para>
-<!-- .LP -->
-If you use Xlib to create your own top-level windows
-(direct children of the root window),
-you must observe the following rules so that all applications interact
-reasonably across the different styles of window management:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-You must never fight with the window manager for the size or
-placement of your top-level window.
- </para>
- </listitem>
- <listitem>
- <para>
-You must be able to deal with whatever size window you get,
-even if this means that your application just prints a message
-like ``Please make me bigger'' in its window.
- </para>
- </listitem>
- <listitem>
- <para>
-You should only attempt to resize or move top-level windows in
-direct response to a user request.
-If a request to change the size of a top-level window fails,
-you must be prepared to live with what you get.
-You are free to resize or move the children of top-level
-windows as necessary.
-(Toolkits often have facilities for automatic relayout.)
- </para>
- </listitem>
- <listitem>
- <para>
-If you do not use a toolkit that automatically sets standard window properties,
-you should set these properties for top-level windows before mapping them.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-For further information,
-see chapter 14 and the <emphasis remap='I'>Inter-Client Communication Conventions Manual</emphasis>.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreateWindow</function>
-is the more general function that allows you to set specific window attributes
-when you create a window.
-<function>XCreateSimpleWindow</function>
-creates a window that inherits its attributes from its parent window.
-</para>
-<para>
-<!-- .LP -->
-<indexterm><primary>Window</primary><secondary>InputOnly</secondary></indexterm>
-The X server acts as if
-<symbol>InputOnly</symbol>
-windows do not exist for
-the purposes of graphics requests, exposure processing, and
-<symbol>VisibilityNotify</symbol>
-events.
-An
-<symbol>InputOnly</symbol>
-window cannot be used as a
-drawable (that is, as a source or destination for graphics requests).
-<symbol>InputOnly</symbol>
-and
-<symbol>InputOutput</symbol>
-windows act identically in other respects (properties,
-grabs, input control, and so on).
-Extension packages can define other classes of windows.
-</para>
-<para>
-<!-- .LP -->
-To create an unmapped window and set its window attributes, use
-<function>XCreateWindow</function>.
-<indexterm significance="preferred"><primary>XCreateWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Window <function>XCreateWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> parent</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>unsignedint<parameter> border_width</parameter></paramdef>
- <paramdef>int<parameter> depth</parameter></paramdef>
- <paramdef>unsignedint<parameter> class</parameter></paramdef>
- <paramdef>Visual<parameter> *visual</parameter></paramdef>
- <paramdef>unsignedlong<parameter> valuemask</parameter></paramdef>
- <paramdef>XSetWindowAttributes<parameter> *attributes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>parent</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the parent window.
-<!-- .ds Xy , which are the top-left outside corner of the created window's \ -->
-borders and are relative to the inside of the parent window's borders
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
-<!-- .ds Wh , which are the created window's inside dimensions \ -->
-and do not include the created window's borders
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
-The dimensions must be nonzero,
-or a
-<errorname>BadValue</errorname>
-error results.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>border_width</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the width of the created window's border in pixels.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>depth</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window's depth.
-A depth of
-<symbol>CopyFromParent</symbol>
-means the depth is taken from the parent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>class</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the created window's class.
-You can pass
-<symbol>InputOutput</symbol>,
-<symbol>InputOnly</symbol>,
-or
-<symbol>CopyFromParent</symbol>.
-A class of
-<symbol>CopyFromParent</symbol>
-means the class
-is taken from the parent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>visual</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the visual type.
-A visual of
-<symbol>CopyFromParent</symbol>
-means the visual type is taken from the
-parent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>valuemask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which window attributes are defined in the attributes
-argument.
-This mask is the bitwise inclusive OR of the valid attribute mask bits.
-If valuemask is zero,
-the attributes are ignored and are not referenced.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>attributes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the structure from which the values (as specified by the value mask)
-are to be taken.
-The value mask should have the appropriate bits
-set to indicate which attributes have been set in the structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreateWindow</function>
-function creates an unmapped subwindow for a specified parent window,
-returns the window ID of the created window,
-and causes the X server to generate a
-<symbol>CreateNotify</symbol>
-event.
-The created window is placed on top in the stacking order
-with respect to siblings.
-</para>
-<para>
-<!-- .LP -->
-The coordinate system has the X axis horizontal and the Y axis vertical
-with the origin [0, 0] at the upper-left corner.
-Coordinates are integral,
-in terms of pixels,
-and coincide with pixel centers.
-Each window and pixmap has its own coordinate system.
-For a window,
-the origin is inside the border at the inside, upper-left corner.
-</para>
-<para>
-<!-- .LP -->
-The border_width for an
-<symbol>InputOnly</symbol>
-window must be zero, or a
-<errorname>BadMatch</errorname>
-error results.
-For class
-<symbol>InputOutput</symbol>,
-the visual type and depth must be a combination supported for the screen,
-or a
-<errorname>BadMatch</errorname>
-error results.
-The depth need not be the same as the parent,
-but the parent must not be a window of class
-<symbol>InputOnly</symbol>,
-or a
-<errorname>BadMatch</errorname>
-error results.
-For an
-<symbol>InputOnly</symbol>
-window,
-the depth must be zero, and the visual must be one supported by the screen.
-If either condition is not met,
-a
-<errorname>BadMatch</errorname>
-error results.
-The parent window, however, may have any depth and class.
-If you specify any invalid window attribute for a window, a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-The created window is not yet displayed (mapped) on the user's display.
-To display the window, call
-<function>XMapWindow</function>.
-The new window initially uses the same cursor as
-its parent.
-A new cursor can be defined for the new window by calling
-<function>XDefineCursor</function>.
-<indexterm><primary>Cursor</primary><secondary>Initial State</secondary></indexterm>
-<indexterm><primary>XDefineCursor</primary></indexterm>
-The window will not be visible on the screen unless it and all of its
-ancestors are mapped and it is not obscured by any of its ancestors.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreateWindow</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadColor</errorname>,
-<errorname>BadCursor</errorname>,
-<errorname>BadMatch</errorname>,
-<errorname>BadPixmap</errorname>,
-<errorname>BadValue</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create an unmapped
-<symbol>InputOutput</symbol>
-subwindow of a given parent window, use
-<function>XCreateSimpleWindow</function>.
-<indexterm significance="preferred"><primary>XCreateSimpleWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Window <function>XCreateSimpleWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> parent</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>unsignedint<parameter> border_width</parameter></paramdef>
- <paramdef>unsignedlong<parameter> border</parameter></paramdef>
- <paramdef>unsignedlong<parameter> background</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>parent</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the parent window.
-<!-- .ds Xy , which are the top-left outside corner of the new window's borders \ -->
-and are relative to the inside of the parent window's borders
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
-<!-- .ds Wh , which are the created window's inside dimensions \ -->
-and do not include the created window's borders
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
-The dimensions must be nonzero,
-or a
-<errorname>BadValue</errorname>
-error results.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>border_width</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the width of the created window's border in pixels.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>border</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the border pixel value of the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>background</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the background pixel value of the window.
-
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreateSimpleWindow</function>
-function creates an unmapped
-<symbol>InputOutput</symbol>
-subwindow for a specified parent window, returns the
-window ID of the created window, and causes the X server to generate a
-<symbol>CreateNotify</symbol>
-event.
-The created window is placed on top in the stacking order with respect to
-siblings.
-Any part of the window that extends outside its parent window is clipped.
-The border_width for an
-<symbol>InputOnly</symbol>
-window must be zero, or a
-<errorname>BadMatch</errorname>
-error results.
-<function>XCreateSimpleWindow</function>
-inherits its depth, class, and visual from its parent.
-All other window attributes, except background and border,
-have their default values.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreateSimpleWindow</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadMatch</errorname>,
-<errorname>BadValue</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect1>
-<sect1 id="Destroying_Windows">
-<title>Destroying Windows</title>
-<!-- .XS -->
-<!-- (SN Destroying Windows -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to destroy a window or destroy all
-subwindows of a window.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To destroy a window and all of its subwindows, use
-<function>XDestroyWindow</function>.
-<indexterm significance="preferred"><primary>XDestroyWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDestroyWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDestroyWindow</function>
-function destroys the specified window as well as all of its subwindows and causes
-the X server to generate a
-<symbol>DestroyNotify</symbol>
-event for each window.
-The window should never be referenced again.
-If the window specified by the w argument is mapped,
-it is unmapped automatically.
-The ordering of the
-<symbol>DestroyNotify</symbol>
-events is such that for any given window being destroyed,
-<symbol>DestroyNotify</symbol>
-is generated on any inferiors of the window before being generated on
-the window itself.
-The ordering among siblings and across subhierarchies is not otherwise
-constrained.
-If the window you specified is a root window, no windows are destroyed.
-Destroying a mapped window will generate
-<symbol>Expose</symbol>
-events on other windows that were obscured by the window being destroyed.
-</para>
-<para>
-<!-- .LP -->
-<function>XDestroyWindow</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To destroy all subwindows of a specified window, use
-<function>XDestroySubwindows</function>.
-<indexterm significance="preferred"><primary>XDestroySubwindows</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDestroySubwindows</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDestroySubwindows</function>
-function destroys all inferior windows of the specified window,
-in bottom-to-top stacking order.
-It causes the X server to generate a
-<symbol>DestroyNotify</symbol>
-event for each window.
-If any mapped
-subwindows were actually destroyed,
-<function>XDestroySubwindows</function>
-causes the X server to generate
-<symbol>Expose</symbol>
-events on the specified window.
-This is much more efficient than deleting many windows
-one at a time because much of the work need be performed only once for all
-of the windows, rather than for each window.
-The subwindows should never be referenced again.
-</para>
-<para>
-<!-- .LP -->
-<function>XDestroySubwindows</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Mapping_Windows_">
-<title>Mapping Windows </title>
-<!-- .XS -->
-<!-- (SN Mapping Windows -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-A window is considered mapped if an
-<function>XMapWindow</function>
-call has been made on it.
-It may not be visible on the screen for one of the following reasons:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-It is obscured by another opaque window.
- </para>
- </listitem>
- <listitem>
- <para>
-One of its ancestors is not mapped.
- </para>
- </listitem>
- <listitem>
- <para>
-It is entirely clipped by an ancestor.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-<symbol>Expose</symbol>
-events are generated for the window when part or all of
-it becomes visible on the screen.
-A client receives the
-<symbol>Expose</symbol>
-events only if it has asked for them.
-Windows retain their position in the stacking order when they are unmapped.
-</para>
-<para>
-<!-- .LP -->
-A window manager may want to control the placement of subwindows.
-If
-<symbol>SubstructureRedirectMask</symbol>
-has been selected by a window manager
-on a parent window (usually a root window),
-a map request initiated by other clients on a child window is not performed,
-and the window manager is sent a
-<symbol>MapRequest</symbol>
-event.
-However, if the override-redirect flag on the child had been set to
-<symbol>True</symbol>
-(usually only on pop-up menus),
-the map request is performed.
-</para>
-<para>
-<!-- .LP -->
-A tiling window manager might decide to reposition and resize other clients'
-windows and then decide to map the window to its final location.
-A window manager that wants to provide decoration might
-reparent the child into a frame first.
-For further information,
-see sections 3.2.8 and 10.10.
-Only a single client at a time can select for
-<symbol>SubstructureRedirectMask</symbol>.
-</para>
-<para>
-<!-- .LP -->
-Similarly, a single client can select for
-<symbol>ResizeRedirectMask</symbol>
-on a parent window.
-Then, any attempt to resize the window by another client is suppressed, and
-the client receives a
-<symbol>ResizeRequest</symbol>
-event.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To map a given window, use
-<function>XMapWindow</function>.
-<indexterm significance="preferred"><primary>XMapWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XMapWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XMapWindow</function>
-function
-maps the window and all of its
-subwindows that have had map requests.
-Mapping a window that has an unmapped ancestor does not display the
-window but marks it as eligible for display when the ancestor becomes
-mapped.
-Such a window is called unviewable.
-When all its ancestors are mapped,
-the window becomes viewable
-and will be visible on the screen if it is not obscured by another window.
-This function has no effect if the window is already mapped.
-</para>
-<para>
-<!-- .LP -->
-If the override-redirect of the window is
-<symbol>False</symbol>
-and if some other client has selected
-<symbol>SubstructureRedirectMask</symbol>
-on the parent window, then the X server generates a
-<symbol>MapRequest</symbol>
-event, and the
-<function>XMapWindow</function>
-function does not map the window.
-Otherwise, the window is mapped, and the X server generates a
-<symbol>MapNotify</symbol>
-event.
-</para>
-<para>
-<!-- .LP -->
-If the window becomes viewable and no earlier contents for it are remembered,
-the X server tiles the window with its background.
-If the window's background is undefined,
-the existing screen contents are not
-altered, and the X server generates zero or more
-<symbol>Expose</symbol>
-events.
-If backing-store was maintained while the window was unmapped, no
-<symbol>Expose</symbol>
-events
-are generated.
-If backing-store will now be maintained,
-a full-window exposure is always generated.
-Otherwise, only visible regions may be reported.
-Similar tiling and exposure take place for any newly viewable inferiors.
-</para>
-<para>
-<!-- .LP -->
-<indexterm><primary>XMapWindow</primary></indexterm>
-If the window is an
-<symbol>InputOutput</symbol>
-window,
-<function>XMapWindow</function>
-generates
-<symbol>Expose</symbol>
-events on each
-<symbol>InputOutput</symbol>
-window that it causes to be displayed.
-If the client maps and paints the window
-and if the client begins processing events,
-the window is painted twice.
-To avoid this,
-first ask for
-<symbol>Expose</symbol>
-events and then map the window,
-so the client processes input events as usual.
-The event list will include
-<symbol>Expose</symbol>
-for each
-window that has appeared on the screen.
-The client's normal response to
-an
-<symbol>Expose</symbol>
-event should be to repaint the window.
-This method usually leads to simpler programs and to proper interaction
-with window managers.
-</para>
-<para>
-<!-- .LP -->
-<function>XMapWindow</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To map and raise a window, use
-<function>XMapRaised</function>.
-<indexterm significance="preferred"><primary>XMapRaised</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XMapRaised</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XMapRaised</function>
-function
-essentially is similar to
-<function>XMapWindow</function>
-in that it maps the window and all of its
-subwindows that have had map requests.
-However, it also raises the specified window to the top of the stack.
-For additional information,
-see
-<function>XMapWindow</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XMapRaised</function>
-can generate multiple
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To map all subwindows for a specified window, use
-<function>XMapSubwindows</function>.
-<indexterm significance="preferred"><primary>XMapSubwindows</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XMapSubwindows</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XMapSubwindows</function>
-<indexterm><primary>XMapSubwindows</primary></indexterm>
-function maps all subwindows for a specified window in top-to-bottom stacking
-order.
-The X server generates
-<symbol>Expose</symbol>
-events on each newly displayed window.
-This may be much more efficient than mapping many windows
-one at a time because the server needs to perform much of the work
-only once, for all of the windows, rather than for each window.
-</para>
-<para>
-<!-- .LP -->
-<function>XMapSubwindows</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Unmapping_Windows">
-<title>Unmapping Windows</title>
-<!-- .XS -->
-<!-- (SN Unmapping Windows -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to unmap a window or all subwindows.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To unmap a window, use
-<function>XUnmapWindow</function>.
-<indexterm significance="preferred"><primary>XUnmapWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XUnmapWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUnmapWindow</function>
-function unmaps the specified window and causes the X server to generate an
-<symbol>UnmapNotify</symbol>
-<indexterm><primary>UnmapNotify Event</primary></indexterm>
-<indexterm><primary>XUnmapWindow</primary></indexterm>
-event.
-If the specified window is already unmapped,
-<function>XUnmapWindow</function>
-has no effect.
-Normal exposure processing on formerly obscured windows is performed.
-Any child window will no longer be visible until another map call is
-made on the parent.
-In other words, the subwindows are still mapped but are not visible
-until the parent is mapped.
-Unmapping a window will generate
-<symbol>Expose</symbol>
-events on windows that were formerly obscured by it.
-</para>
-<para>
-<!-- .LP -->
-<function>XUnmapWindow</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To unmap all subwindows for a specified window, use
-<function>XUnmapSubwindows</function>.
-<indexterm significance="preferred"><primary>XUnmapSubwindows</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XUnmapSubwindows</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUnmapSubwindows</function>
-function unmaps all subwindows for the specified window in bottom-to-top
-stacking order.
-It causes the X server to generate an
-<symbol>UnmapNotify</symbol>
-event on each subwindow and
-<symbol>Expose</symbol>
-events on formerly obscured windows.
-<indexterm><primary>UnmapNotify Event</primary></indexterm>
-Using this function is much more efficient than unmapping multiple windows
-one at a time because the server needs to perform much of the work
-only once, for all of the windows, rather than for each window.
-</para>
-<para>
-<!-- .LP -->
-<function>XUnmapSubwindows</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Configuring_Windows">
-<title>Configuring Windows</title>
-<!-- .XS -->
-<!-- (SN Configuring Windows -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-</para>
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to
-move a window, resize a window, move and resize a window, or
-change a window's border width.
-To change one of these parameters,
-set the appropriate member of the
-<structname>XWindowChanges</structname>
-structure and OR in the corresponding value mask in subsequent calls to
-<function>XConfigureWindow</function>.
-The symbols for the value mask bits and the
-<structname>XWindowChanges</structname>
-structure are:
-<!-- .sM -->
-</para>
-<para>
-<!-- .LP -->
-
-<literallayout class="monospaced">
-/* Configure window value mask bits */
-#define CWX (1&lt;&lt;0)
-#define CWY (1&lt;&lt;1)
-#define CWWidth (1&lt;&lt;2)
-#define CWHeight (1&lt;&lt;3)
-#define CWBorderWidth (1&lt;&lt;4)
-#define CWSibling (1&lt;&lt;5)
-#define CWStackMode (1&lt;&lt;6)
-</literallayout>
-
-<indexterm significance="preferred"><primary>XWindowChanges</primary></indexterm>
-<literallayout class="monospaced">
-/* Values */
-
-typedef struct {
- int x, y;
- int width, height;
- int border_width;
- Window sibling;
- int stack_mode;
-} XWindowChanges;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The x and y members are used to set the window's x and y coordinates,
-which are relative to the parent's origin
-and indicate the position of the upper-left outer corner of the window.
-The width and height members are used to set the inside size of the window,
-not including the border, and must be nonzero, or a
-<errorname>BadValue</errorname>
-error results.
-Attempts to configure a root window have no effect.
-</para>
-<para>
-<!-- .LP -->
-The border_width member is used to set the width of the border in pixels.
-Note that setting just the border width leaves the outer-left corner of the window
-in a fixed position but moves the absolute position of the window's origin.
-If you attempt to set the border-width attribute of an
-<symbol>InputOnly</symbol>
-window nonzero, a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-The sibling member is used to set the sibling window for stacking operations.
-The stack_mode member is used to set how the window is to be restacked
-and can be set to
-<symbol>Above</symbol>,
-<symbol>Below</symbol>,
-<symbol>TopIf</symbol>,
-<symbol>BottomIf</symbol>,
-or
-<symbol>Opposite</symbol>.
-</para>
-<para>
-<!-- .LP -->
-If the override-redirect flag of the window is
-<symbol>False</symbol>
-and if some other client has selected
-<symbol>SubstructureRedirectMask</symbol>
-on the parent, the X server generates a
-<symbol>ConfigureRequest</symbol>
-event, and no further processing is performed.
-Otherwise,
-if some other client has selected
-<symbol>ResizeRedirectMask</symbol>
-on the window and the inside
-width or height of the window is being changed,
-a
-<symbol>ResizeRequest</symbol>
-event is generated, and the current inside width and height are
-used instead.
-Note that the override-redirect flag of the window has no effect
-on
-<symbol>ResizeRedirectMask</symbol>
-and that
-<symbol>SubstructureRedirectMask</symbol>
-on the parent has precedence over
-<symbol>ResizeRedirectMask</symbol>
-on the window.
-</para>
-<para>
-<!-- .LP -->
-When the geometry of the window is changed as specified,
-the window is restacked among siblings, and a
-<symbol>ConfigureNotify</symbol>
-event is generated if the state of the window actually changes.
-<symbol>GravityNotify</symbol>
-events are generated after
-<symbol>ConfigureNotify</symbol>
-events.
-If the inside width or height of the window has actually changed,
-children of the window are affected as specified.
-</para>
-<para>
-<!-- .LP -->
-If a window's size actually changes,
-the window's subwindows move according to their window gravity.
-Depending on the window's bit gravity,
-the contents of the window also may be moved (see section 3.2.3).
-</para>
-<para>
-<!-- .LP -->
-If regions of the window were obscured but now are not,
-exposure processing is performed on these formerly obscured windows,
-including the window itself and its inferiors.
-As a result of increasing the width or height,
-exposure processing is also performed on any new regions of the window
-and any regions where window contents are lost.
-</para>
-<para>
-<!-- .LP -->
-The restack check (specifically, the computation for
-<symbol>BottomIf</symbol>,
-<symbol>TopIf</symbol>,
-and
-<symbol>Opposite</symbol>)
-is performed with respect to the window's final size and position (as
-controlled by the other arguments of the request), not its initial position.
-If a sibling is specified without a stack_mode,
-a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-If a sibling and a stack_mode are specified,
-the window is restacked as follows:
-</para>
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <tbody>
- <row>
- <entry><symbol>Above</symbol></entry>
- <entry>The window is placed just above the sibling.</entry>
- </row>
- <row>
- <entry><symbol>Below</symbol></entry>
- <entry>The window is placed just below the sibling.</entry>
- </row>
- <row>
- <entry><symbol>TopIf</symbol></entry>
- <entry>If the sibling occludes the window, the window is placed at the top of the stack.</entry>
- </row>
- <row>
- <entry><symbol>BottomIf</symbol></entry>
- <entry>If the window occludes the sibling, the window is placed at the bottom of the stack.</entry>
- </row>
- <row>
- <entry><symbol>Opposite</symbol></entry>
- <entry>
-If the sibling occludes the window, the window is placed at the top of the stack.
-If the window occludes the sibling,
-the window is placed at the bottom of the stack.
- </entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-If a stack_mode is specified but no sibling is specified,
-the window is restacked as follows:
-</para>
-
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <tbody>
- <row>
- <entry><symbol>Above</symbol></entry>
- <entry>The window is placed at the top of the stack.</entry>
- </row>
- <row>
- <entry><symbol>Below</symbol></entry>
- <entry>The window is placed at the bottom of the stack.</entry>
- </row>
- <row>
- <entry><symbol>TopIf</symbol></entry>
- <entry>
-If any sibling occludes the window, the window is placed at
-the top of the stack.
- </entry>
- </row>
- <row>
- <entry>
-If the window occludes any sibling, the window is placed at
-the bottom of the stack.
- </entry>
- </row>
- <row>
- <entry><symbol>Opposite</symbol></entry>
- <entry>
-If any sibling occludes the window, the window
-is placed at the top of the stack.
-If the window occludes any sibling,
-the window is placed at the bottom of the stack.
- </entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-Attempts to configure a root window have no effect.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To configure a window's size, location, stacking, or border, use
-<function>XConfigureWindow</function>.
-<indexterm significance="preferred"><primary>XConfigureWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XConfigureWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>unsignedint<parameter> value_mask</parameter></paramdef>
- <paramdef>XWindowChanges<parameter> *values</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Wi to be reconfigured -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window (Wi.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which values are to be set using information in
-the values structure.
-This mask is the bitwise inclusive OR of the valid configure window values bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>values</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XWindowChanges</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XConfigureWindow</function>
-function uses the values specified in the
-<structname>XWindowChanges</structname>
-structure to reconfigure a window's size, position, border, and stacking order.
-Values not specified are taken from the existing geometry of the window.
-</para>
-<para>
-<!-- .LP -->
-If a sibling is specified without a stack_mode or if the window
-is not actually a sibling,
-a
-<errorname>BadMatch</errorname>
-error results.
-Note that the computations for
-<symbol>BottomIf</symbol>,
-<symbol>TopIf</symbol>,
-and
-<symbol>Opposite</symbol>
-are performed with respect to the window's final geometry (as controlled by the
-other arguments passed to
-<function>XConfigureWindow</function>),
-not its initial geometry.
-Any backing store contents of the window, its
-inferiors, and other newly visible windows are either discarded or
-changed to reflect the current screen contents
-(depending on the implementation).
-</para>
-<para>
-<!-- .LP -->
-<function>XConfigureWindow</function>
-can generate
-<errorname>BadMatch</errorname>,
-<errorname>BadValue</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To move a window without changing its size, use
-<function>XMoveWindow</function>.
-<indexterm significance="preferred"><primary>XMoveWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XMoveWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Wi to be moved -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window (Wi.
-<!-- .ds Xy , which define the new location of the top-left pixel \ -->
-of the window's border or the window itself if it has no border
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XMoveWindow</function>
-function moves the specified window to the specified x and y coordinates,
-but it does not change the window's size, raise the window, or
-change the mapping state of the window.
-Moving a mapped window may or may not lose the window's contents
-depending on if the window is obscured by nonchildren
-and if no backing store exists.
-If the contents of the window are lost,
-the X server generates
-<symbol>Expose</symbol>
-events.
-Moving a mapped window generates
-<symbol>Expose</symbol>
-events on any formerly obscured windows.
-</para>
-<para>
-<!-- .LP -->
-If the override-redirect flag of the window is
-<symbol>False</symbol>
-and some
-other client has selected
-<symbol>SubstructureRedirectMask</symbol>
-on the parent, the X server generates a
-<symbol>ConfigureRequest</symbol>
-event, and no further processing is
-performed.
-Otherwise, the window is moved.
-</para>
-<para>
-<!-- .LP -->
-<function>XMoveWindow</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To change a window's size without changing the upper-left coordinate, use
-<function>XResizeWindow</function>.
-<indexterm significance="preferred"><primary>XResizeWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XResizeWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
-<!-- .ds Wh , which are the interior dimensions of the window \ -->
-after the call completes
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XResizeWindow</function>
-function changes the inside dimensions of the specified window, not including
-its borders.
-This function does not change the window's upper-left coordinate or
-the origin and does not restack the window.
-Changing the size of a mapped window may lose its contents and generate
-<symbol>Expose</symbol>
-events.
-If a mapped window is made smaller,
-changing its size generates
-<symbol>Expose</symbol>
-events on windows that the mapped window formerly obscured.
-</para>
-<para>
-<!-- .LP -->
-If the override-redirect flag of the window is
-<symbol>False</symbol>
-and some
-other client has selected
-<symbol>SubstructureRedirectMask</symbol>
-on the parent, the X server generates a
-<symbol>ConfigureRequest</symbol>
-event, and no further processing is performed.
-If either width or height is zero,
-a
-<errorname>BadValue</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XResizeWindow</function>
-can generate
-<errorname>BadValue</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To change the size and location of a window, use
-<function>XMoveResizeWindow</function>.
-<indexterm significance="preferred"><primary>XMoveResizeWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XMoveResizeWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Wi to be reconfigured -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window (Wi.
-<!-- .ds Xy , which define the new position of the window relative to its parent -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
-<!-- .ds Wh , which define the interior size of the window -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XMoveResizeWindow</function>
-function changes the size and location of the specified window
-without raising it.
-Moving and resizing a mapped window may generate an
-<symbol>Expose</symbol>
-event on the window.
-Depending on the new size and location parameters,
-moving and resizing a window may generate
-<symbol>Expose</symbol>
-events on windows that the window formerly obscured.
-</para>
-<para>
-<!-- .LP -->
-If the override-redirect flag of the window is
-<symbol>False</symbol>
-and some
-other client has selected
-<symbol>SubstructureRedirectMask</symbol>
-on the parent, the X server generates a
-<symbol>ConfigureRequest</symbol>
-event, and no further processing is performed.
-Otherwise, the window size and location are changed.
-</para>
-<para>
-<!-- .LP -->
-<function>XMoveResizeWindow</function>
-can generate
-<errorname>BadValue</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To change the border width of a given window, use
-<function>XSetWindowBorderWidth</function>.
-<indexterm significance="preferred"><primary>XSetWindowBorderWidth</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetWindowBorderWidth</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>unsignedint<parameter> width</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the width of the window border.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWindowBorderWidth</function>
-function sets the specified window's border width to the specified width.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetWindowBorderWidth</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Changing_Window_Stacking_Order">
-<title>Changing Window Stacking Order</title>
-<!-- .XS -->
-<!-- (SN Changing Window Stacking Order -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-</para>
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to raise, lower, circulate,
-or restack windows.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To raise a window so that no sibling window obscures it, use
-<function>XRaiseWindow</function>.
-<indexterm significance="preferred"><primary>XRaiseWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XRaiseWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XRaiseWindow</function>
-function
-raises the specified window to the top of the stack so that no sibling window
-obscures it.
-If the windows are regarded as overlapping sheets of paper stacked
-on a desk,
-then raising a window is analogous to moving the sheet to the top of
-the stack but leaving its x and y location on the desk constant.
-Raising a mapped window may generate
-<symbol>Expose</symbol>
-events for the window and any mapped subwindows that were formerly obscured.
-</para>
-<para>
-<!-- .LP -->
-If the override-redirect attribute of the window is
-<symbol>False</symbol>
-and some
-other client has selected
-<symbol>SubstructureRedirectMask</symbol>
-on the parent, the X server generates a
-<symbol>ConfigureRequest</symbol>
-event, and no processing is performed.
-Otherwise, the window is raised.
-</para>
-<para>
-<!-- .LP -->
-<function>XRaiseWindow</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To lower a window so that it does not obscure any sibling windows, use
-<function>XLowerWindow</function>.
-<indexterm significance="preferred"><primary>XLowerWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XLowerWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XLowerWindow</function>
-function lowers the specified window to the bottom of the stack
-so that it does not obscure any sibling
-windows.
-If the windows are regarded as overlapping sheets of paper
-stacked on a desk, then lowering a window is analogous to moving the
-sheet to the bottom of the stack but leaving its x and y location on
-the desk constant.
-Lowering a mapped window will generate
-<symbol>Expose</symbol>
-events on any windows it formerly obscured.
-</para>
-<para>
-<!-- .LP -->
-If the override-redirect attribute of the window is
-<symbol>False</symbol>
-and some
-other client has selected
-<symbol>SubstructureRedirectMask</symbol>
-on the parent, the X server generates a
-<symbol>ConfigureRequest</symbol>
-event, and no processing is performed.
-Otherwise, the window is lowered to the bottom of the
-stack.
-</para>
-<para>
-<!-- .LP -->
-<function>XLowerWindow</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To circulate a subwindow up or down, use
-<function>XCirculateSubwindows</function>.
-<indexterm significance="preferred"><primary>XCirculateSubwindows</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XCirculateSubwindows</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>int<parameter> direction</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>direction</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the direction (up or down) that you want to circulate
-the window.
-You can pass
-<symbol>RaiseLowest</symbol>
-or
-<symbol>LowerHighest</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCirculateSubwindows</function>
-function circulates children of the specified window in the specified
-direction.
-If you specify
-<symbol>RaiseLowest</symbol>,
-<function>XCirculateSubwindows</function>
-raises the lowest mapped child (if any) that is occluded
-by another child to the top of the stack.
-If you specify
-<symbol>LowerHighest</symbol>,
-<function>XCirculateSubwindows</function>
-lowers the highest mapped child (if any) that occludes another child
-to the bottom of the stack.
-Exposure processing is then performed on formerly obscured windows.
-If some other client has selected
-<symbol>SubstructureRedirectMask</symbol>
-on the window, the X server generates a
-<symbol>CirculateRequest</symbol>
-event, and no further processing is performed.
-If a child is actually restacked,
-the X server generates a
-<symbol>CirculateNotify</symbol>
-event.
-</para>
-<para>
-<!-- .LP -->
-<function>XCirculateSubwindows</function>
-can generate
-<errorname>BadValue</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To raise the lowest mapped child of a window that is partially or completely
-occluded by another child, use
-<function>XCirculateSubwindowsUp</function>.
-<indexterm significance="preferred"><primary>XCirculateSubwindowsUp</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XCirculateSubwindowsUp</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCirculateSubwindowsUp</function>
-function raises the lowest mapped child of the specified window that
-is partially
-or completely
-occluded by another child.
-Completely unobscured children are not affected.
-This is a convenience function equivalent to
-<function>XCirculateSubwindows</function>
-with
-<symbol>RaiseLowest</symbol>
-specified.
-</para>
-<para>
-<!-- .LP -->
-<function>XCirculateSubwindowsUp</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To lower the highest mapped child of a window that partially or
-completely occludes another child, use
-<function>XCirculateSubwindowsDown</function>.
-<indexterm significance="preferred"><primary>XCirculateSubwindowsDown</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XCirculateSubwindowsDown</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCirculateSubwindowsDown</function>
-function lowers the highest mapped child of the specified window that partially
-or completely occludes another child.
-Completely unobscured children are not affected.
-This is a convenience function equivalent to
-<function>XCirculateSubwindows</function>
-with
-<symbol>LowerHighest</symbol>
-specified.
-</para>
-<para>
-<!-- .LP -->
-<function>XCirculateSubwindowsDown</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To restack a set of windows from top to bottom, use
-<function>XRestackWindows</function>.
-<indexterm significance="preferred"><primary>XRestackWindows</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XRestackWindows</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> windows[]</parameter></paramdef>
- <paramdef>int<parameter> nwindows</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>windows</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array containing the windows to be restacked.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nwindows</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of windows to be restacked.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XRestackWindows</function>
-function restacks the windows in the order specified,
-from top to bottom.
-The stacking order of the first window in the windows array is unaffected,
-but the other windows in the array are stacked underneath the first window,
-in the order of the array.
-The stacking order of the other windows is not affected.
-For each window in the window array that is not a child of the specified window,
-a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-If the override-redirect attribute of a window is
-<symbol>False</symbol>
-and some
-other client has selected
-<symbol>SubstructureRedirectMask</symbol>
-on the parent, the X server generates
-<symbol>ConfigureRequest</symbol>
-events for each window whose override-redirect flag is not set,
-and no further processing is performed.
-Otherwise, the windows will be restacked in top-to-bottom order.
-</para>
-<para>
-<!-- .LP -->
-<function>XRestackWindows</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Changing_Window_Attributes">
-<title>Changing Window Attributes</title>
-<!-- .XS -->
-<!-- (SN Changing Window Attributes -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-</para>
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set window attributes.
-<function>XChangeWindowAttributes</function>
-is the more general function that allows you to set one or more window
-attributes provided by the
-<structname>XSetWindowAttributes</structname>
-structure.
-The other functions described in this section allow you to set one specific
-window attribute, such as a window's background.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To change one or more attributes for a given window, use
-<function>XChangeWindowAttributes</function>.
-<indexterm significance="preferred"><primary>XChangeWindowAttributes</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XChangeWindowAttributes</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>unsignedlong<parameter> valuemask</parameter></paramdef>
- <paramdef>XSetWindowAttributes<parameter> *attributes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>valuemask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which window attributes are defined in the attributes
-argument.
-This mask is the bitwise inclusive OR of the valid attribute mask bits.
-If valuemask is zero,
-the attributes are ignored and are not referenced.
-The values and restrictions are
-the same as for
-<function>XCreateWindow</function>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
-
- </term>
- <listitem>
- <para>
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>attributes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the structure from which the values (as specified by the value mask)
-are to be taken.
-The value mask should have the appropriate bits
-set to indicate which attributes have been set in the structure
-(see section 3.2).
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Depending on the valuemask,
-the
-<function>XChangeWindowAttributes</function>
-function uses the window attributes in the
-<structname>XSetWindowAttributes</structname>
-structure to change the specified window attributes.
-Changing the background does not cause the window contents to be
-changed.
-To repaint the window and its background, use
-<function>XClearWindow</function>.
-Setting the border or changing the background such that the
-border tile origin changes causes the border to be repainted.
-Changing the background of a root window to
-<symbol>None</symbol>
-or
-<symbol>ParentRelative</symbol>
-restores the default background pixmap.
-Changing the border of a root window to
-<symbol>CopyFromParent</symbol>
-restores the default border pixmap.
-Changing the win-gravity does not affect the current position of the
-window.
-Changing the backing-store of an obscured window to
-<symbol>WhenMapped</symbol>
-or
-<symbol>Always</symbol>,
-or changing the backing-planes, backing-pixel, or
-save-under of a mapped window may have no immediate effect.
-Changing the colormap of a window (that is, defining a new map, not
-changing the contents of the existing map) generates a
-<symbol>ColormapNotify</symbol>
-event.
-Changing the colormap of a visible window may have no
-immediate effect on the screen because the map may not be installed
-(see
-<function>XInstallColormap</function>).
-Changing the cursor of a root window to
-<symbol>None</symbol>
-restores the default
-cursor.
-Whenever possible, you are encouraged to share colormaps.
-</para>
-<para>
-<!-- .LP -->
-Multiple clients can select input on the same window.
-Their event masks are maintained separately.
-When an event is generated,
-it is reported to all interested clients.
-However, only one client at a time can select for
-<symbol>SubstructureRedirectMask</symbol>,
-<symbol>ResizeRedirectMask</symbol>,
-and
-<symbol>ButtonPressMask</symbol>.
-If a client attempts to select any of these event masks
-and some other client has already selected one,
-a
-<errorname>BadAccess</errorname>
-error results.
-There is only one do-not-propagate-mask for a window,
-not one per client.
-</para>
-<para>
-<!-- .LP -->
-<function>XChangeWindowAttributes</function>
-can generate
-<errorname>BadAccess</errorname>,
-<errorname>BadColor</errorname>,
-<errorname>BadCursor</errorname>,
-<errorname>BadMatch</errorname>,
-<errorname>BadPixmap</errorname>,
-<errorname>BadValue</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the background of a window to a given pixel, use
-<function>XSetWindowBackground</function>.
-<indexterm significance="preferred"><primary>XSetWindowBackground</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetWindowBackground</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>unsignedlong<parameter> background_pixel</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>background_pixel</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the pixel that is to be used for the background.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWindowBackground</function>
-function sets the background of the window to the specified pixel value.
-Changing the background does not cause the window contents to be changed.
-<function>XSetWindowBackground</function>
-uses a pixmap of undefined size filled with the pixel value you passed.
-If you try to change the background of an
-<symbol>InputOnly</symbol>
-window, a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetWindowBackground</function>
-can generate
-<errorname>BadMatch</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set the background of a window to a given pixmap, use
-<function>XSetWindowBackgroundPixmap</function>.
-<indexterm><primary>Window</primary><secondary>background</secondary></indexterm>
-<indexterm significance="preferred"><primary>XSetWindowBackgroundPixmap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetWindowBackgroundPixmap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Pixmap<parameter> background_pixmap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>background_pixmap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the background pixmap,
-<symbol>ParentRelative</symbol>,
-or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm><primary>Resource IDs</primary><secondary>freeing</secondary></indexterm>
-<indexterm><primary>Freeing</primary><secondary>resources</secondary></indexterm>
-The
-<function>XSetWindowBackgroundPixmap</function>
-function sets the background pixmap of the window to the specified pixmap.
-The background pixmap can immediately be freed if no further explicit
-references to it are to be made.
-If
-<symbol>ParentRelative</symbol>
-is specified,
-the background pixmap of the window's parent is used,
-or on the root window, the default background is restored.
-If you try to change the background of an
-<symbol>InputOnly</symbol>
-window, a
-<errorname>BadMatch</errorname>
-error results.
-If the background is set to
-<symbol>None</symbol>,
-the window has no defined background.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetWindowBackgroundPixmap</function>
-can generate
-<errorname>BadMatch</errorname>,
-<errorname>BadPixmap</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-<!-- .NT Note -->
-<function>XSetWindowBackground</function>
-and
-<function>XSetWindowBackgroundPixmap</function>
-do not change the current contents of the window.
-<!-- .NE -->
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To change and repaint a window's border to a given pixel, use
-<function>XSetWindowBorder</function>.
-<indexterm significance="preferred"><primary>XSetWindowBorder</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetWindowBorder</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>unsignedlong<parameter> border_pixel</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>border_pixel</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the entry in the colormap.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWindowBorder</function>
-function sets the border of the window to the pixel value you specify.
-If you attempt to perform this on an
-<symbol>InputOnly</symbol>
-window, a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetWindowBorder</function>
-can generate
-<errorname>BadMatch</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To change and repaint the border tile of a given window, use
-<function>XSetWindowBorderPixmap</function>.
-<indexterm significance="preferred"><primary>XSetWindowBorderPixmap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetWindowBorderPixmap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Pixmap<parameter> border_pixmap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>border_pixmap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the border pixmap or
-<symbol>CopyFromParent</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWindowBorderPixmap</function>
-function sets the border pixmap of the window to the pixmap you specify.
-The border pixmap can be freed immediately if no further explicit
-references to it are to be made.
-If you specify
-<symbol>CopyFromParent</symbol>,
-a copy of the parent window's border pixmap is used.
-If you attempt to perform this on an
-<symbol>InputOnly</symbol>
-window, a
-<errorname>BadMatch</errorname>
-error results.
-<indexterm><primary>Resource IDs</primary><secondary>freeing</secondary></indexterm>
-<indexterm><primary>Freeing</primary><secondary>resources</secondary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<function>XSetWindowBorderPixmap</function>
-can generate
-<errorname>BadMatch</errorname>,
-<errorname>BadPixmap</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the colormap of a given window, use
-<function>XSetWindowColormap</function>.
-<indexterm significance="preferred"><primary>XSetWindowColormap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetWindowColormap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWindowColormap</function>
-function sets the specified colormap of the specified window.
-The colormap must have the same visual type as the window,
-or a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetWindowColormap</function>
-can generate
-<errorname>BadColor</errorname>,
-<errorname>BadMatch</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To define which cursor will be used in a window, use
-<function>XDefineCursor</function>.
-<indexterm><primary>Window</primary><secondary>defining the cursor</secondary></indexterm>
-<indexterm significance="preferred"><primary>XDefineCursor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDefineCursor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Cursor<parameter> cursor</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>cursor</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the cursor that is to be displayed or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If a cursor is set, it will be used when the pointer is in the window.
-If the cursor is
-<symbol>None</symbol>,
-it is equivalent to
-<function>XUndefineCursor</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XDefineCursor</function>
-can generate
-<errorname>BadCursor</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To undefine the cursor in a given window, use
-<function>XUndefineCursor</function>.
-<indexterm><primary>Window</primary><secondary>undefining the cursor</secondary></indexterm>
-<indexterm significance="preferred"><primary>XUndefineCursor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XUndefineCursor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUndefineCursor</function>
-function undoes the effect of a previous
-<function>XDefineCursor</function>
-for this window.
-When the pointer is in the window,
-the parent's cursor will now be used.
-On the root window,
-the default cursor is restored.
-</para>
-<para>
-<!-- .LP -->
-<function>XUndefineCursor</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-<!-- .bp -->
-
-</para>
-</sect1>
-</chapter>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<chapter id="window_functions"><title>Window Functions</title>
+<sect1 id="Visual_Types">
+<title>Visual Types</title>
+<!-- .XS -->
+<!-- (SN Visual Types -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>Visual Type</primary></indexterm>
+On some display hardware,
+it may be possible to deal with color resources in more than one way.
+For example, you may be able to deal with a screen of either 12-bit depth
+with arbitrary mapping of pixel to color (pseudo-color) or 24-bit depth
+with 8 bits of the pixel dedicated to each of red, green, and blue.
+These different ways of dealing with the visual aspects of the screen
+are called visuals.
+For each screen of the display, there may be a list of valid visual types
+supported at different depths of the screen.
+Because default windows and visual types are defined for each screen,
+most simple applications need not deal with this complexity.
+Xlib provides macros and functions that return the default root window,
+the default depth of the default root window, and the default visual type
+(see sections 2.2.1 and 16.7).
+</para>
+<para>
+<!-- .LP -->
+Xlib uses an opaque
+<structname>Visual</structname>
+<indexterm significance="preferred"><primary>Visual</primary></indexterm>
+structure that contains information about the possible color mapping.
+The visual utility functions (see section 16.7) use an
+<structname>XVisualInfo</structname>
+structure to return this information to an application.
+The members of this structure pertinent to this discussion are class, red_mask,
+green_mask, blue_mask, bits_per_rgb, and colormap_size.
+The class member specifies one of the possible visual classes of the screen
+and can be
+<indexterm><primary>Visual Classes</primary><secondary>StaticGray</secondary></indexterm>
+<indexterm><primary>Visual Classes</primary><secondary>StaticColor</secondary></indexterm>
+<indexterm><primary>Visual Classes</primary><secondary>TrueColor</secondary></indexterm>
+<indexterm><primary>Visual Classes</primary><secondary>StaticColor</secondary></indexterm>
+<indexterm><primary>Visual Classes</primary><secondary>GrayScale</secondary></indexterm>
+<indexterm><primary>Visual Classes</primary><secondary>PseudoColor</secondary></indexterm>
+<symbol>StaticGray</symbol>,
+<symbol>StaticColor</symbol>,
+<symbol>TrueColor</symbol>,
+<symbol>GrayScale</symbol>,
+<symbol>PseudoColor</symbol>,
+or
+<symbol>DirectColor</symbol>.
+</para>
+<para>
+<!-- .LP -->
+The following concepts may serve to make the explanation of
+visual types clearer.
+The screen can be color or grayscale,
+can have a colormap that is writable or read-only,
+and can also have a colormap whose indices are decomposed into separate
+<acronym>RGB</acronym> pieces, provided one is not on a grayscale screen.
+This leads to the following diagram:
+</para>
+
+<literallayout class="monospaced">
+ Color Gray-Scale
+ R/O R/W R/O R/W
+----------------------------------------------
+ Undecomposed Static Pseudo Static Gray
+ Colormap Color Color Gray Scale
+
+ Decomposed True Direct
+ Colormap Color Color
+----------------------------------------------
+</literallayout>
+
+<para>
+<!-- .LP -->
+Conceptually,
+as each pixel is read out of video memory for display on the screen,
+it goes through a look-up stage by indexing into a colormap.
+Colormaps can be manipulated arbitrarily on some hardware,
+in limited ways on other hardware, and not at all on other hardware.
+The visual types affect the colormap and
+the <acronym>RGB</acronym> values in the following ways:
+</para>
+<para>
+<!-- .LP -->
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+For
+<symbol>PseudoColor</symbol>,
+a pixel value indexes a colormap to produce
+independent <acronym>RGB</acronym> values, and the <acronym>RGB</acronym> values can be changed dynamically.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<symbol>GrayScale</symbol>
+is treated the same way as
+<symbol>PseudoColor</symbol>
+except that the primary that drives the screen is undefined.
+Thus, the client should always store the
+same value for red, green, and blue in the colormaps.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+For
+<symbol>DirectColor</symbol>,
+a pixel value is decomposed into separate <acronym>RGB</acronym> subfields, and each
+subfield separately indexes the colormap for the corresponding value.
+The <acronym>RGB</acronym> values can be changed dynamically.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<symbol>TrueColor</symbol>
+is treated the same way as
+<symbol>DirectColor</symbol>
+except that the colormap has predefined, read-only <acronym>RGB</acronym> values.
+These <acronym>RGB</acronym> values are server dependent but provide linear or near-linear
+ramps in each primary.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<symbol>StaticColor</symbol>
+is treated the same way as
+<symbol>PseudoColor</symbol>
+except that the colormap has predefined,
+read-only, server-dependent <acronym>RGB</acronym> values.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<symbol>StaticGray</symbol>
+is treated the same way as
+<symbol>StaticColor</symbol>
+except that the <acronym>RGB</acronym> values are equal for any single pixel
+value, thus resulting in shades of gray.
+<symbol>StaticGray</symbol>
+with a two-entry
+colormap can be thought of as monochrome.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The red_mask, green_mask, and blue_mask members are only defined for
+<symbol>DirectColor</symbol>
+and
+<symbol>TrueColor</symbol>.
+Each has one contiguous set of bits with no
+intersections.
+The bits_per_rgb member specifies the log base 2 of the
+number of distinct color values (individually) of red, green, and blue.
+Actual <acronym>RGB</acronym> values are unsigned 16-bit numbers.
+The colormap_size member defines the number of available colormap entries
+in a newly created colormap.
+For
+<symbol>DirectColor</symbol>
+and
+<symbol>TrueColor</symbol>,
+this is the size of an individual pixel subfield.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the visual ID from a
+<structname>Visual</structname>,
+use
+<function>XVisualIDFromVisual</function>.
+<indexterm significance="preferred"><primary>XVisualIDFromVisual</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xvisualidfromvisual'>
+<funcprototype>
+ <funcdef>VisualID <function>XVisualIDFromVisual</function></funcdef>
+ <paramdef>Visual *<parameter>visual</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>visual</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the visual type.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XVisualIDFromVisual</function>
+function returns the visual ID for the specified visual type.
+</para>
+</sect1>
+<sect1 id="Window_Attributes">
+<title>Window Attributes</title>
+<!-- .XS -->
+<!-- (SN Window Attributes -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Window</primary></indexterm>
+<indexterm><primary>Window</primary><secondary>attributes</secondary></indexterm>
+All
+<symbol>InputOutput</symbol>
+windows have a border width of zero or more pixels, an optional background,
+an event suppression mask (which suppresses propagation of events from
+children), and a property list (see section 4.3).
+The window border and background can be a solid color or a pattern, called
+a tile.
+All windows except the root have a parent and are clipped by their parent.
+If a window is stacked on top of another window, it obscures that other
+window for the purpose of input.
+If a window has a background (almost all do), it obscures the other
+window for purposes of output.
+Attempts to output to the obscured area do nothing,
+and no input events (for example, pointer motion) are generated for the
+obscured area.
+</para>
+<para>
+<!-- .LP -->
+Windows also have associated property lists (see section 4.3).
+</para>
+<para>
+<!-- .LP -->
+Both
+<symbol>InputOutput</symbol>
+and
+<symbol>InputOnly</symbol>
+windows have the following common attributes,
+which are the only attributes of an
+<symbol>InputOnly</symbol>
+window:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+win-gravity
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+event-mask
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+do-not-propagate-mask
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+override-redirect
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+cursor
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+If you specify any other attributes for an
+<symbol>InputOnly</symbol>
+window,
+a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<symbol>InputOnly</symbol>
+windows are used for controlling input events in situations where
+<symbol>InputOutput</symbol>
+windows are unnecessary.
+<symbol>InputOnly</symbol>
+windows are invisible; can only be used to control such things as
+cursors, input event generation, and grabbing;
+and cannot be used in any graphics requests.
+Note that
+<symbol>InputOnly</symbol>
+windows cannot have
+<symbol>InputOutput</symbol>
+windows as inferiors.
+</para>
+<para>
+<!-- .LP -->
+Windows have borders of a programmable width and pattern
+as well as a background pattern or tile.
+<indexterm><primary>Tile</primary><secondary>pixmaps</secondary></indexterm>
+Pixel values can be used for solid colors.
+<indexterm><primary>Resource IDs</primary><secondary>freeing</secondary></indexterm>
+<indexterm><primary>Freeing</primary><secondary>resources</secondary></indexterm>
+The background and border pixmaps can be destroyed immediately after
+creating the window if no further explicit references to them
+are to be made.
+<indexterm ><primary>Tile</primary><secondary>mode</secondary></indexterm>
+The pattern can either be relative to the parent
+or absolute.
+If
+<symbol>ParentRelative</symbol>,
+the parent's background is used.
+</para>
+<para>
+<!-- .LP -->
+When windows are first created,
+they are not visible (not mapped) on the screen.
+Any output to a window that is not visible on the screen
+and that does not have backing store will be discarded.
+<indexterm><primary>Window</primary><secondary>mapping</secondary></indexterm>
+An application may wish to create a window long before it is
+mapped to the screen.
+When a window is eventually mapped to the screen
+(using
+<function>XMapWindow</function>),
+<indexterm><primary>XMapWindow</primary></indexterm>
+the X server generates an
+<symbol>Expose</symbol>
+event for the window if backing store has not been maintained.
+</para>
+<para>
+<!-- .LP -->
+A window manager can override your choice of size,
+border width, and position for a top-level window.
+Your program must be prepared to use the actual size and position
+of the top window.
+It is not acceptable for a client application to resize itself
+unless in direct response to a human command to do so.
+Instead, either your program should use the space given to it,
+or if the space is too small for any useful work, your program
+might ask the user to resize the window.
+The border of your top-level window is considered fair game
+for window managers.
+</para>
+<para>
+<!-- .LP -->
+To set an attribute of a window,
+set the appropriate member of the
+<structname>XSetWindowAttributes</structname>
+structure and OR in the corresponding value bitmask in your subsequent calls to
+<function>XCreateWindow</function>
+and
+<function>XChangeWindowAttributes</function>,
+or use one of the other convenience functions that set the appropriate
+attribute.
+The symbols for the value mask bits and the
+<structname>XSetWindowAttributes</structname>
+structure are:
+<!-- .sM -->
+</para>
+<para>
+<!-- .LP -->
+/* Window attribute value mask bits */
+
+
+<literallayout class="monospaced">
+/* Window attribute value mask bits */
+#define CWBackPixmap (1L&lt;&lt;0)
+#define CWBackPixel (1L&lt;&lt;1)
+#define CWBorderPixmap (1L&lt;&lt;2)
+#define CWBorderPixel (1L&lt;&lt;3)
+#define CWBitGravity (1L&lt;&lt;4)
+#define CWWinGravity (1L&lt;&lt;5)
+#define CWBackingStore (1L&lt;&lt;6)
+#define CWBackingPlanes (1L&lt;&lt;7)
+#define CWBackingPixel (1L&lt;&lt;8)
+#define CWOverrideRedirect (1L&lt;&lt;9)
+#define CWSaveUnder (1L&lt;&lt;10)
+#define CWEventMask (1L&lt;&lt;11)
+#define CWDontPropagate (1L&lt;&lt;12)
+#define CWColormap (1L&lt;&lt;13)
+#define CWCursor (1L&lt;&lt;14)
+</literallayout>
+
+<indexterm significance="preferred"><primary>XSetWindowAttributes</primary></indexterm>
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+/* Values */
+
+typedef struct {
+ Pixmap background_pixmap; /* background, None, or ParentRelative */
+ unsigned long background_pixel; /* background pixel */
+ Pixmap border_pixmap; /* border of the window or CopyFromParent */
+ unsigned long border_pixel; /* border pixel value */
+ int bit_gravity; /* one of bit gravity values */
+ int win_gravity; /* one of the window gravity values */
+ int backing_store; /* NotUseful, WhenMapped, Always */
+ unsigned long backing_planes; /* planes to be preserved if possible */
+ unsigned long backing_pixel; /* value to use in restoring planes */
+ Bool save_under; /* should bits under be saved? (popups) */
+ long event_mask; /* set of events that should be saved */
+ long do_not_propagate_mask; /* set of events that should not propagate */
+ Bool override_redirect; /* boolean value for override_redirect */
+ Colormap colormap; /* color map to be associated with window */
+ Cursor cursor; /* cursor to be displayed (or None) */
+} XSetWindowAttributes;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The following lists the defaults for each window attribute and indicates
+whether the attribute is applicable to
+<symbol>InputOutput</symbol>
+and
+<symbol>InputOnly</symbol>
+windows:
+</para>
+<informaltable>
+ <tgroup cols='4' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <colspec colname='c3'/>
+ <colspec colname='c4'/>
+ <thead>
+ <row>
+ <entry>Attribute</entry>
+ <entry>Default</entry>
+ <entry>InputOutput</entry>
+ <entry>nputOnly</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>background-pixmap</entry>
+ <entry><symbol>None</symbol></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry>background-pixel</entry>
+ <entry>Undefined</entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry>border-pixmap</entry>
+ <entry><symbol>CopyFromParent</symbol></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry>border-pixel</entry>
+ <entry>Undefined</entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry>bit-gravity</entry>
+ <entry><symbol>ForgetGravity</symbol></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry>win-gravity</entry>
+ <entry><symbol>NorthWestGravity</symbol></entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ </row>
+ <row>
+ <entry>backing-store</entry>
+ <entry><symbol>NotUseful</symbol></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry>backing-planes</entry>
+ <entry>All ones</entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry>backing-pixel</entry>
+ <entry>zero</entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry>save-under</entry>
+ <entry><symbol>False</symbol></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry>event-mask</entry>
+ <entry>empty set</entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ </row>
+ <row>
+ <entry>do-not-propagate-mask</entry>
+ <entry>empty set</entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ </row>
+ <row>
+ <entry>override-redirect</entry>
+ <entry><symbol>False</symbol></entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ </row>
+ <row>
+ <entry>colormap</entry>
+ <entry><symbol>CopyFromParent</symbol></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry>cursor</entry>
+ <entry><symbol>None</symbol></entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<sect2 id="Background_Attribute">
+<title>Background Attribute</title>
+<!-- .XS -->
+<!-- (SN Background Attribute -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Only
+<symbol>InputOutput</symbol>
+windows can have a background.
+You can set the background of an
+<symbol>InputOutput</symbol>
+window by using a pixel or a pixmap.
+</para>
+<para>
+<!-- .LP -->
+The background-pixmap attribute of a window specifies the pixmap to be used for
+a window's background.
+This pixmap can be of any size, although some sizes may be faster than others.
+The background-pixel attribute of a window specifies a pixel value used to paint
+a window's background in a single color.
+</para>
+<para>
+<!-- .LP -->
+You can set the background-pixmap to a pixmap,
+<symbol>None</symbol>
+(default), or
+<symbol>ParentRelative</symbol>.
+You can set the background-pixel of a window to any pixel value (no default).
+If you specify a background-pixel,
+it overrides either the default background-pixmap
+or any value you may have set in the background-pixmap.
+A pixmap of an undefined size that is filled with the background-pixel is used
+for the background.
+Range checking is not performed on the background pixel;
+it simply is truncated to the appropriate number of bits.
+</para>
+<para>
+<!-- .LP -->
+If you set the background-pixmap,
+it overrides the default.
+The background-pixmap and the window must have the same depth,
+or a
+<errorname>BadMatch</errorname>
+error results.
+If you set background-pixmap to
+<symbol>None</symbol>,
+the window has no defined background.
+If you set the background-pixmap to
+<symbol>ParentRelative</symbol>:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The parent window's background-pixmap is used.
+The child window, however, must have the same depth as
+its parent,
+or a
+<errorname>BadMatch</errorname>
+error results.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If the parent window has a background-pixmap of
+<symbol>None</symbol>,
+the window also has a background-pixmap of
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A copy of the parent window's background-pixmap is not made.
+The parent's background-pixmap is examined each time the child window's
+background-pixmap is required.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The background tile origin always aligns with the parent window's
+background tile origin.
+If the background-pixmap is not
+<symbol>ParentRelative</symbol>,
+the background tile origin is the child window's origin.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Setting a new background, whether by setting background-pixmap or
+background-pixel, overrides any previous background.
+The background-pixmap can be freed immediately if no further explicit reference
+is made to it (the X server will keep a copy to use when needed).
+If you later draw into the pixmap used for the background,
+what happens is undefined because the
+X implementation is free to make a copy of the pixmap or
+to use the same pixmap.
+</para>
+<para>
+<!-- .LP -->
+When no valid contents are available for regions of a window
+and either the regions are visible or the server is maintaining backing store,
+the server automatically tiles the regions with the window's background
+unless the window has a background of
+<symbol>None</symbol>.
+If the background is
+<symbol>None</symbol>,
+the previous screen contents from other windows of the same depth as the window
+are simply left in place as long as the contents come from the parent of the
+window or an inferior of the parent.
+Otherwise, the initial contents of the exposed regions are undefined.
+<symbol>Expose</symbol>
+events are then generated for the regions, even if the background-pixmap
+is
+<symbol>None</symbol>
+(see section 10.9).
+</para>
+</sect2>
+<sect2 id="Border_Attribute">
+<title>Border Attribute</title>
+<!-- .XS -->
+<!-- (SN Border Attribute -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Only
+<symbol>InputOutput</symbol>
+windows can have a border.
+You can set the border of an
+<symbol>InputOutput</symbol>
+window by using a pixel or a pixmap.
+</para>
+<para>
+<!-- .LP -->
+The border-pixmap attribute of a window specifies the pixmap to be used
+for a window's border.
+The border-pixel attribute of a window specifies a pixmap of undefined size
+filled with that pixel be used for a window's border.
+Range checking is not performed on the background pixel;
+it simply is truncated to the appropriate number of bits.
+The border tile origin is always the same as the background tile origin.
+</para>
+<para>
+<!-- .LP -->
+You can also set the border-pixmap to a pixmap of any size (some may be faster
+than others) or to
+<symbol>CopyFromParent</symbol>
+(default).
+You can set the border-pixel to any pixel value (no default).
+</para>
+<para>
+<!-- .LP -->
+If you set a border-pixmap,
+it overrides the default.
+The border-pixmap and the window must have the same depth,
+or a
+<errorname>BadMatch</errorname>
+error results.
+If you set the border-pixmap to
+<symbol>CopyFromParent</symbol>,
+the parent window's border-pixmap is copied.
+Subsequent changes to the parent window's border attribute do not affect
+the child window.
+However, the child window must have the same depth as the parent window,
+or a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+The border-pixmap can be freed immediately if no further explicit reference
+is made to it.
+If you later draw into the pixmap used for the border,
+what happens is undefined because the
+X implementation is free either to make a copy of the pixmap or
+to use the same pixmap.
+If you specify a border-pixel,
+it overrides either the default border-pixmap
+or any value you may have set in the border-pixmap.
+All pixels in the window's border will be set to the border-pixel.
+Setting a new border, whether by setting border-pixel or by setting
+border-pixmap, overrides any previous border.
+</para>
+<para>
+<!-- .LP -->
+Output to a window is always clipped to the inside of the window.
+Therefore, graphics operations never affect the window border.
+</para>
+</sect2>
+<sect2 id="Gravity_Attributes">
+<title>Gravity Attributes</title>
+<!-- .XS -->
+<!-- (SN Gravity Attributes -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The bit gravity of a window defines which region of the window should be
+retained when an
+<symbol>InputOutput</symbol>
+window is resized.
+The default value for the bit-gravity attribute is
+<symbol>ForgetGravity</symbol>.
+The window gravity of a window allows you to define how the
+<symbol>InputOutput</symbol>
+or
+<symbol>InputOnly</symbol>
+window should be repositioned if its parent is resized.
+The default value for the win-gravity attribute is
+<symbol>NorthWestGravity</symbol>.
+</para>
+<para>
+<!-- .LP -->
+If the inside width or height of a window is not changed
+and if the window is moved or its border is changed,
+then the contents of the window are not lost but move with the window.
+Changing the inside width or height of the window causes its contents to be
+moved or lost (depending on the bit-gravity of the window) and causes
+children to be reconfigured (depending on their win-gravity).
+For a
+change of width and height, the (x, y) pairs are defined:
+</para>
+<para>
+<!-- .LP -->
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <thead>
+ <row>
+ <entry>Gravity Direction</entry>
+ <entry>Coordinates</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><symbol>NorthWestGravity</symbol></entry>
+ <entry>(0, 0)</entry>
+ </row>
+ <row>
+ <entry><symbol>NorthGravity</symbol></entry>
+ <entry>(Width/2, 0)</entry>
+ </row>
+ <row>
+ <entry><symbol>NorthEastGravity</symbol></entry>
+ <entry>(Width, 0)</entry>
+ </row>
+ <row>
+ <entry><symbol>WestGravity</symbol></entry>
+ <entry>(0, Height/2)</entry>
+ </row>
+ <row>
+ <entry><symbol>CenterGravity</symbol></entry>
+ <entry>(Width/2, Height/2)</entry>
+ </row>
+ <row>
+ <entry><symbol>EastGravity</symbol></entry>
+ <entry>(Width, Height/2)</entry>
+ </row>
+ <row>
+ <entry><symbol>SouthWestGravity</symbol></entry>
+ <entry>(0, Height)</entry>
+ </row>
+ <row>
+ <entry><symbol>SouthGravity</symbol></entry>
+ <entry>(Width/2, Height)</entry>
+ </row>
+ <row>
+ <entry><symbol>SouthEastGravity</symbol></entry>
+ <entry>(Width, Height)</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+</para>
+<para>
+<!-- .LP -->
+When a window with one of these bit-gravity values is resized,
+the corresponding pair
+defines the change in position of each pixel in the window.
+When a window with one of these win-gravities has its parent window resized,
+the corresponding pair defines the change in position of the window
+within the parent.
+When a window is so repositioned, a
+<symbol>GravityNotify</symbol>
+event is generated (see section 10.10.5).
+</para>
+<para>
+<!-- .LP -->
+A bit-gravity of
+<symbol>StaticGravity</symbol>
+indicates that the contents or origin should not move relative to the
+origin of the root window.
+If the change in size of the window is coupled with a change in position (x, y),
+then for bit-gravity the change in position of each pixel is (&minus;x, &minus;y), and for
+win-gravity the change in position of a child when its parent is so resized is
+(&minus;x, &minus;y).
+Note that
+<symbol>StaticGravity</symbol>
+still only takes effect when the width or height of the window is changed,
+not when the window is moved.
+</para>
+<para>
+<!-- .LP -->
+A bit-gravity of
+<symbol>ForgetGravity</symbol>
+indicates that the window's contents are always discarded after a size change,
+even if a backing store or save under has been requested.
+The window is tiled with its background
+and zero or more
+<symbol>Expose</symbol>
+events are generated.
+If no background is defined, the existing screen contents are not
+altered.
+Some X servers may also ignore the specified bit-gravity and
+always generate
+<symbol>Expose</symbol>
+events.
+</para>
+<para>
+<!-- .LP -->
+The contents and borders of inferiors are not affected by their parent's
+bit-gravity.
+A server is permitted to ignore the specified bit-gravity and use
+<symbol>Forget</symbol>
+instead.
+</para>
+<para>
+<!-- .LP -->
+A win-gravity of
+<symbol>UnmapGravity</symbol>
+is like
+<symbol>NorthWestGravity</symbol>
+(the window is not moved),
+except the child is also
+unmapped when the parent is resized,
+and an
+<symbol>UnmapNotify</symbol>
+event is
+generated.
+</para>
+</sect2>
+<sect2 id="Backing_Store_Attribute">
+<title>Backing Store Attribute</title>
+<!-- .XS -->
+<!-- (SN Backing Store Attribute -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Some implementations of the X server may choose to maintain the contents of
+<symbol>InputOutput</symbol>
+windows.
+If the X server maintains the contents of a window,
+the off-screen saved pixels
+are known as backing store.
+The backing store advises the X server on what to do
+with the contents of a window.
+The backing-store attribute can be set to
+<symbol>NotUseful</symbol>
+(default),
+<symbol>WhenMapped</symbol>,
+or
+<symbol>Always</symbol>.
+</para>
+<para>
+<!-- .LP -->
+A backing-store attribute of
+<symbol>NotUseful</symbol>
+advises the X server that
+maintaining contents is unnecessary,
+although some X implementations may
+still choose to maintain contents and, therefore, not generate
+<symbol>Expose</symbol>
+events.
+A backing-store attribute of
+<symbol>WhenMapped</symbol>
+advises the X server that maintaining contents of
+obscured regions when the window is mapped would be beneficial.
+In this case,
+the server may generate an
+<symbol>Expose</symbol>
+event when the window is created.
+A backing-store attribute of
+<symbol>Always</symbol>
+advises the X server that maintaining contents even when
+the window is unmapped would be beneficial.
+Even if the window is larger than its parent,
+this is a request to the X server to maintain complete contents,
+not just the region within the parent window boundaries.
+While the X server maintains the window's contents,
+<symbol>Expose</symbol>
+events normally are not generated,
+but the X server may stop maintaining
+contents at any time.
+</para>
+<para>
+<!-- .LP -->
+When the contents of obscured regions of a window are being maintained,
+regions obscured by noninferior windows are included in the destination
+of graphics requests (and source, when the window is the source).
+However, regions obscured by inferior windows are not included.
+</para>
+</sect2>
+<sect2 id="Save_Under_Flag">
+<title>Save Under Flag</title>
+<!-- .XS -->
+<!-- (SN Save Under Flag -->
+<!-- .XE -->
+<indexterm><primary>Save Unders</primary></indexterm>
+<para>
+<!-- .LP -->
+Some server implementations may preserve contents of
+<symbol>InputOutput</symbol>
+windows under other
+<symbol>InputOutput</symbol>
+windows.
+This is not the same as preserving the contents of a window for you.
+You may get better visual
+appeal if transient windows (for example, pop-up menus) request that the system
+preserve the screen contents under them,
+so the temporarily obscured applications do not have to repaint.
+</para>
+<para>
+<!-- .LP -->
+You can set the save-under flag to
+<symbol>True</symbol>
+or
+<symbol>False</symbol>
+(default).
+If save-under is
+<symbol>True</symbol>,
+the X server is advised that, when this window is mapped,
+saving the contents of windows it obscures would be beneficial.
+</para>
+</sect2>
+<sect2 id="Backing_Planes_and_Backing_Pixel_Attributes">
+<title>Backing Planes and Backing Pixel Attributes</title>
+<!-- .XS -->
+<!-- (SN Backing Planes and Backing Pixel Attributes -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+You can set backing planes to indicate (with bits set to 1)
+which bit planes of an
+<symbol>InputOutput</symbol>
+window hold dynamic data that must be preserved in backing store
+and during save unders.
+The default value for the backing-planes attribute is all bits set to 1.
+You can set backing pixel to specify what bits to use in planes not
+covered by backing planes.
+The default value for the backing-pixel attribute is all bits set to 0.
+The X server is free to save only the specified bit planes in the backing store
+or the save under and is free to regenerate the remaining planes with
+the specified pixel value.
+Any extraneous bits in these values (that is, those bits beyond
+the specified depth of the window) may be simply ignored.
+If you request backing store or save unders,
+you should use these members to minimize the amount of off-screen memory
+required to store your window.
+</para>
+</sect2>
+<sect2 id="Event_Mask_and_Do_Not_Propagate_Mask_Attributes">
+<title>Event Mask and Do Not Propagate Mask Attributes</title>
+<!-- .XS -->
+<!-- (SN Event Mask and Do Not Propagate Mask Attributes -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The event mask defines which events the client is interested in for this
+<symbol>InputOutput</symbol>
+or
+<symbol>InputOnly</symbol>
+window (or, for some event types, inferiors of this window).
+The event mask is the bitwise inclusive OR of zero or more of the
+valid event mask bits.
+You can specify that no maskable events are reported by setting
+<symbol>NoEventMask</symbol>
+(default).
+</para>
+<para>
+<!-- .LP -->
+The do-not-propagate-mask attribute
+defines which events should not be propagated to
+ancestor windows when no client has the event type selected in this
+<symbol>InputOutput</symbol>
+or
+<symbol>InputOnly</symbol>
+window.
+The do-not-propagate-mask is the bitwise inclusive OR of zero or more
+of the following masks:
+<symbol>KeyPress</symbol>,
+<symbol>KeyRelease</symbol>,
+<symbol>ButtonPress</symbol>,
+<symbol>ButtonRelease</symbol>,
+<symbol>PointerMotion</symbol>,
+<symbol>Button1Motion</symbol>,
+<symbol>Button2Motion</symbol>,
+<symbol>Button3Motion</symbol>,
+<symbol>Button4Motion</symbol>,
+<symbol>Button5Motion</symbol>,
+and
+<symbol>ButtonMotion</symbol>.
+You can specify that all events are propagated by setting
+<symbol>NoEventMask</symbol>
+(default).
+</para>
+</sect2>
+<sect2 id="Override_Redirect_Flag">
+<title>Override Redirect Flag</title>
+<!-- .XS -->
+<!-- (SN Override Redirect Flag -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To control window placement or to add decoration,
+a window manager often needs to intercept (redirect) any map or configure
+request.
+Pop-up windows, however, often need to be mapped without a window manager
+getting in the way.
+To control whether an
+<symbol>InputOutput</symbol>
+or
+<symbol>InputOnly</symbol>
+window is to ignore these structure control facilities,
+use the override-redirect flag.
+</para>
+<para>
+<!-- .LP -->
+The override-redirect flag specifies whether map and configure requests
+on this window should override a
+<symbol>SubstructureRedirectMask</symbol>
+on the parent.
+You can set the override-redirect flag to
+<symbol>True</symbol>
+or
+<symbol>False</symbol>
+(default).
+Window managers use this information to avoid tampering with pop-up windows
+(see also chapter 14).
+</para>
+</sect2>
+<sect2 id="Colormap_Attribute">
+<title>Colormap Attribute</title>
+<!-- .XS -->
+<!-- (SN Colormap Attribute -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The colormap attribute specifies which colormap best reflects the true
+colors of the
+<symbol>InputOutput</symbol>
+window.
+The colormap must have the same visual type as the window,
+or a
+<errorname>BadMatch</errorname>
+error results.
+X servers capable of supporting multiple
+hardware colormaps can use this information,
+and window managers can use it for calls to
+<function>XInstallColormap</function>.
+You can set the colormap attribute to a colormap or to
+<symbol>CopyFromParent</symbol>
+(default).
+</para>
+<para>
+<!-- .LP -->
+If you set the colormap to
+<symbol>CopyFromParent</symbol>,
+the parent window's colormap is copied and used by its child.
+However, the child window must have the same visual type as the parent,
+or a
+<errorname>BadMatch</errorname>
+error results.
+The parent window must not have a colormap of
+<symbol>None</symbol>,
+or a
+<errorname>BadMatch</errorname>
+error results.
+The colormap is copied by sharing the colormap object between the child
+and parent, not by making a complete copy of the colormap contents.
+Subsequent changes to the parent window's colormap attribute do
+not affect the child window.
+</para>
+</sect2>
+<sect2 id="Cursor_Attribute">
+<title>Cursor Attribute</title>
+<!-- .XS -->
+<!-- (SN Cursor Attribute -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The cursor attribute specifies which cursor is to be used when the pointer is
+in the
+<symbol>InputOutput</symbol>
+or
+<symbol>InputOnly</symbol>
+window.
+You can set the cursor to a cursor or
+<symbol>None</symbol>
+(default).
+</para>
+<para>
+<!-- .LP -->
+If you set the cursor to
+<symbol>None</symbol>,
+the parent's cursor is used when the
+pointer is in the
+<symbol>InputOutput</symbol>
+or
+<symbol>InputOnly</symbol>
+window, and any change in the parent's cursor will cause an
+immediate change in the displayed cursor.
+By calling
+<function>XFreeCursor</function>,
+the cursor can be freed immediately as long as no further explicit reference
+to it is made.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Creating_Windows">
+<title>Creating Windows</title>
+<!-- .XS -->
+<!-- (SN Creating Windows -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides basic ways for creating windows,
+and toolkits often supply higher-level functions specifically for
+creating and placing top-level windows,
+which are discussed in the appropriate toolkit documentation.
+If you do not use a toolkit, however,
+you must provide some standard information or hints for the window
+manager by using the Xlib inter-client communication functions
+(see chapter 14).
+</para>
+<para>
+<!-- .LP -->
+If you use Xlib to create your own top-level windows
+(direct children of the root window),
+you must observe the following rules so that all applications interact
+reasonably across the different styles of window management:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+You must never fight with the window manager for the size or
+placement of your top-level window.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+You must be able to deal with whatever size window you get,
+even if this means that your application just prints a message
+like ``Please make me bigger'' in its window.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+You should only attempt to resize or move top-level windows in
+direct response to a user request.
+If a request to change the size of a top-level window fails,
+you must be prepared to live with what you get.
+You are free to resize or move the children of top-level
+windows as necessary.
+(Toolkits often have facilities for automatic relayout.)
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If you do not use a toolkit that automatically sets standard window properties,
+you should set these properties for top-level windows before mapping them.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+For further information,
+see chapter 14 and the <emphasis remap='I'>Inter-Client Communication Conventions Manual</emphasis>.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreateWindow</function>
+is the more general function that allows you to set specific window attributes
+when you create a window.
+<function>XCreateSimpleWindow</function>
+creates a window that inherits its attributes from its parent window.
+</para>
+<para>
+<!-- .LP -->
+<indexterm><primary>Window</primary><secondary>InputOnly</secondary></indexterm>
+The X server acts as if
+<symbol>InputOnly</symbol>
+windows do not exist for
+the purposes of graphics requests, exposure processing, and
+<symbol>VisibilityNotify</symbol>
+events.
+An
+<symbol>InputOnly</symbol>
+window cannot be used as a
+drawable (that is, as a source or destination for graphics requests).
+<symbol>InputOnly</symbol>
+and
+<symbol>InputOutput</symbol>
+windows act identically in other respects (properties,
+grabs, input control, and so on).
+Extension packages can define other classes of windows.
+</para>
+<para>
+<!-- .LP -->
+To create an unmapped window and set its window attributes, use
+<function>XCreateWindow</function>.
+<indexterm significance="preferred"><primary>XCreateWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreatewindow'>
+<funcprototype>
+ <funcdef>Window <function>XCreateWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> parent</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>unsignedint<parameter> border_width</parameter></paramdef>
+ <paramdef>int<parameter> depth</parameter></paramdef>
+ <paramdef>unsignedint<parameter> class</parameter></paramdef>
+ <paramdef>Visual<parameter> *visual</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> valuemask</parameter></paramdef>
+ <paramdef>XSetWindowAttributes<parameter> *attributes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>parent</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the parent window.
+<!-- .ds Xy , which are the top-left outside corner of the created window's \ -->
+borders and are relative to the inside of the parent window's borders
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+<!-- .ds Wh , which are the created window's inside dimensions \ -->
+and do not include the created window's borders
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+The dimensions must be nonzero,
+or a
+<errorname>BadValue</errorname>
+error results.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>border_width</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the width of the created window's border in pixels.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>depth</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window's depth.
+A depth of
+<symbol>CopyFromParent</symbol>
+means the depth is taken from the parent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>class</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the created window's class.
+You can pass
+<symbol>InputOutput</symbol>,
+<symbol>InputOnly</symbol>,
+or
+<symbol>CopyFromParent</symbol>.
+A class of
+<symbol>CopyFromParent</symbol>
+means the class
+is taken from the parent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>visual</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the visual type.
+A visual of
+<symbol>CopyFromParent</symbol>
+means the visual type is taken from the
+parent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>valuemask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which window attributes are defined in the attributes
+argument.
+This mask is the bitwise inclusive OR of the valid attribute mask bits.
+If valuemask is zero,
+the attributes are ignored and are not referenced.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>attributes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the structure from which the values (as specified by the value mask)
+are to be taken.
+The value mask should have the appropriate bits
+set to indicate which attributes have been set in the structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreateWindow</function>
+function creates an unmapped subwindow for a specified parent window,
+returns the window ID of the created window,
+and causes the X server to generate a
+<symbol>CreateNotify</symbol>
+event.
+The created window is placed on top in the stacking order
+with respect to siblings.
+</para>
+<para>
+<!-- .LP -->
+The coordinate system has the X axis horizontal and the Y axis vertical
+with the origin [0, 0] at the upper-left corner.
+Coordinates are integral,
+in terms of pixels,
+and coincide with pixel centers.
+Each window and pixmap has its own coordinate system.
+For a window,
+the origin is inside the border at the inside, upper-left corner.
+</para>
+<para>
+<!-- .LP -->
+The border_width for an
+<symbol>InputOnly</symbol>
+window must be zero, or a
+<errorname>BadMatch</errorname>
+error results.
+For class
+<symbol>InputOutput</symbol>,
+the visual type and depth must be a combination supported for the screen,
+or a
+<errorname>BadMatch</errorname>
+error results.
+The depth need not be the same as the parent,
+but the parent must not be a window of class
+<symbol>InputOnly</symbol>,
+or a
+<errorname>BadMatch</errorname>
+error results.
+For an
+<symbol>InputOnly</symbol>
+window,
+the depth must be zero, and the visual must be one supported by the screen.
+If either condition is not met,
+a
+<errorname>BadMatch</errorname>
+error results.
+The parent window, however, may have any depth and class.
+If you specify any invalid window attribute for a window, a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+The created window is not yet displayed (mapped) on the user's display.
+To display the window, call
+<function>XMapWindow</function>.
+The new window initially uses the same cursor as
+its parent.
+A new cursor can be defined for the new window by calling
+<function>XDefineCursor</function>.
+<indexterm><primary>Cursor</primary><secondary>Initial State</secondary></indexterm>
+<indexterm><primary>XDefineCursor</primary></indexterm>
+The window will not be visible on the screen unless it and all of its
+ancestors are mapped and it is not obscured by any of its ancestors.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreateWindow</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadColor</errorname>,
+<errorname>BadCursor</errorname>,
+<errorname>BadMatch</errorname>,
+<errorname>BadPixmap</errorname>,
+<errorname>BadValue</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create an unmapped
+<symbol>InputOutput</symbol>
+subwindow of a given parent window, use
+<function>XCreateSimpleWindow</function>.
+<indexterm significance="preferred"><primary>XCreateSimpleWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreatesimplewindow'>
+<funcprototype>
+ <funcdef>Window <function>XCreateSimpleWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> parent</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>unsignedint<parameter> border_width</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> border</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> background</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>parent</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the parent window.
+<!-- .ds Xy , which are the top-left outside corner of the new window's borders \ -->
+and are relative to the inside of the parent window's borders
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+<!-- .ds Wh , which are the created window's inside dimensions \ -->
+and do not include the created window's borders
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+The dimensions must be nonzero,
+or a
+<errorname>BadValue</errorname>
+error results.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>border_width</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the width of the created window's border in pixels.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>border</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the border pixel value of the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>background</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the background pixel value of the window.
+
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreateSimpleWindow</function>
+function creates an unmapped
+<symbol>InputOutput</symbol>
+subwindow for a specified parent window, returns the
+window ID of the created window, and causes the X server to generate a
+<symbol>CreateNotify</symbol>
+event.
+The created window is placed on top in the stacking order with respect to
+siblings.
+Any part of the window that extends outside its parent window is clipped.
+The border_width for an
+<symbol>InputOnly</symbol>
+window must be zero, or a
+<errorname>BadMatch</errorname>
+error results.
+<function>XCreateSimpleWindow</function>
+inherits its depth, class, and visual from its parent.
+All other window attributes, except background and border,
+have their default values.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreateSimpleWindow</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadMatch</errorname>,
+<errorname>BadValue</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect1>
+<sect1 id="Destroying_Windows">
+<title>Destroying Windows</title>
+<!-- .XS -->
+<!-- (SN Destroying Windows -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to destroy a window or destroy all
+subwindows of a window.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To destroy a window and all of its subwindows, use
+<function>XDestroyWindow</function>.
+<indexterm significance="preferred"><primary>XDestroyWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdestroywindow'>
+<funcprototype>
+ <funcdef><function>XDestroyWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDestroyWindow</function>
+function destroys the specified window as well as all of its subwindows and causes
+the X server to generate a
+<symbol>DestroyNotify</symbol>
+event for each window.
+The window should never be referenced again.
+If the window specified by the w argument is mapped,
+it is unmapped automatically.
+The ordering of the
+<symbol>DestroyNotify</symbol>
+events is such that for any given window being destroyed,
+<symbol>DestroyNotify</symbol>
+is generated on any inferiors of the window before being generated on
+the window itself.
+The ordering among siblings and across subhierarchies is not otherwise
+constrained.
+If the window you specified is a root window, no windows are destroyed.
+Destroying a mapped window will generate
+<symbol>Expose</symbol>
+events on other windows that were obscured by the window being destroyed.
+</para>
+<para>
+<!-- .LP -->
+<function>XDestroyWindow</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To destroy all subwindows of a specified window, use
+<function>XDestroySubwindows</function>.
+<indexterm significance="preferred"><primary>XDestroySubwindows</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdestroysubwindows'>
+<funcprototype>
+ <funcdef><function>XDestroySubwindows</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDestroySubwindows</function>
+function destroys all inferior windows of the specified window,
+in bottom-to-top stacking order.
+It causes the X server to generate a
+<symbol>DestroyNotify</symbol>
+event for each window.
+If any mapped
+subwindows were actually destroyed,
+<function>XDestroySubwindows</function>
+causes the X server to generate
+<symbol>Expose</symbol>
+events on the specified window.
+This is much more efficient than deleting many windows
+one at a time because much of the work need be performed only once for all
+of the windows, rather than for each window.
+The subwindows should never be referenced again.
+</para>
+<para>
+<!-- .LP -->
+<function>XDestroySubwindows</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Mapping_Windows_">
+<title>Mapping Windows </title>
+<!-- .XS -->
+<!-- (SN Mapping Windows -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+A window is considered mapped if an
+<function>XMapWindow</function>
+call has been made on it.
+It may not be visible on the screen for one of the following reasons:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+It is obscured by another opaque window.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+One of its ancestors is not mapped.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+It is entirely clipped by an ancestor.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+<symbol>Expose</symbol>
+events are generated for the window when part or all of
+it becomes visible on the screen.
+A client receives the
+<symbol>Expose</symbol>
+events only if it has asked for them.
+Windows retain their position in the stacking order when they are unmapped.
+</para>
+<para>
+<!-- .LP -->
+A window manager may want to control the placement of subwindows.
+If
+<symbol>SubstructureRedirectMask</symbol>
+has been selected by a window manager
+on a parent window (usually a root window),
+a map request initiated by other clients on a child window is not performed,
+and the window manager is sent a
+<symbol>MapRequest</symbol>
+event.
+However, if the override-redirect flag on the child had been set to
+<symbol>True</symbol>
+(usually only on pop-up menus),
+the map request is performed.
+</para>
+<para>
+<!-- .LP -->
+A tiling window manager might decide to reposition and resize other clients'
+windows and then decide to map the window to its final location.
+A window manager that wants to provide decoration might
+reparent the child into a frame first.
+For further information,
+see sections 3.2.8 and 10.10.
+Only a single client at a time can select for
+<symbol>SubstructureRedirectMask</symbol>.
+</para>
+<para>
+<!-- .LP -->
+Similarly, a single client can select for
+<symbol>ResizeRedirectMask</symbol>
+on a parent window.
+Then, any attempt to resize the window by another client is suppressed, and
+the client receives a
+<symbol>ResizeRequest</symbol>
+event.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To map a given window, use
+<function>XMapWindow</function>.
+<indexterm significance="preferred"><primary>XMapWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmapwindow'>
+<funcprototype>
+ <funcdef><function>XMapWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XMapWindow</function>
+function
+maps the window and all of its
+subwindows that have had map requests.
+Mapping a window that has an unmapped ancestor does not display the
+window but marks it as eligible for display when the ancestor becomes
+mapped.
+Such a window is called unviewable.
+When all its ancestors are mapped,
+the window becomes viewable
+and will be visible on the screen if it is not obscured by another window.
+This function has no effect if the window is already mapped.
+</para>
+<para>
+<!-- .LP -->
+If the override-redirect of the window is
+<symbol>False</symbol>
+and if some other client has selected
+<symbol>SubstructureRedirectMask</symbol>
+on the parent window, then the X server generates a
+<symbol>MapRequest</symbol>
+event, and the
+<function>XMapWindow</function>
+function does not map the window.
+Otherwise, the window is mapped, and the X server generates a
+<symbol>MapNotify</symbol>
+event.
+</para>
+<para>
+<!-- .LP -->
+If the window becomes viewable and no earlier contents for it are remembered,
+the X server tiles the window with its background.
+If the window's background is undefined,
+the existing screen contents are not
+altered, and the X server generates zero or more
+<symbol>Expose</symbol>
+events.
+If backing-store was maintained while the window was unmapped, no
+<symbol>Expose</symbol>
+events
+are generated.
+If backing-store will now be maintained,
+a full-window exposure is always generated.
+Otherwise, only visible regions may be reported.
+Similar tiling and exposure take place for any newly viewable inferiors.
+</para>
+<para>
+<!-- .LP -->
+<indexterm><primary>XMapWindow</primary></indexterm>
+If the window is an
+<symbol>InputOutput</symbol>
+window,
+<function>XMapWindow</function>
+generates
+<symbol>Expose</symbol>
+events on each
+<symbol>InputOutput</symbol>
+window that it causes to be displayed.
+If the client maps and paints the window
+and if the client begins processing events,
+the window is painted twice.
+To avoid this,
+first ask for
+<symbol>Expose</symbol>
+events and then map the window,
+so the client processes input events as usual.
+The event list will include
+<symbol>Expose</symbol>
+for each
+window that has appeared on the screen.
+The client's normal response to
+an
+<symbol>Expose</symbol>
+event should be to repaint the window.
+This method usually leads to simpler programs and to proper interaction
+with window managers.
+</para>
+<para>
+<!-- .LP -->
+<function>XMapWindow</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To map and raise a window, use
+<function>XMapRaised</function>.
+<indexterm significance="preferred"><primary>XMapRaised</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmapraised'>
+<funcprototype>
+ <funcdef><function>XMapRaised</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XMapRaised</function>
+function
+essentially is similar to
+<function>XMapWindow</function>
+in that it maps the window and all of its
+subwindows that have had map requests.
+However, it also raises the specified window to the top of the stack.
+For additional information,
+see
+<function>XMapWindow</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XMapRaised</function>
+can generate multiple
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To map all subwindows for a specified window, use
+<function>XMapSubwindows</function>.
+<indexterm significance="preferred"><primary>XMapSubwindows</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmapsubwindows'>
+<funcprototype>
+ <funcdef><function>XMapSubwindows</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XMapSubwindows</function>
+<indexterm><primary>XMapSubwindows</primary></indexterm>
+function maps all subwindows for a specified window in top-to-bottom stacking
+order.
+The X server generates
+<symbol>Expose</symbol>
+events on each newly displayed window.
+This may be much more efficient than mapping many windows
+one at a time because the server needs to perform much of the work
+only once, for all of the windows, rather than for each window.
+</para>
+<para>
+<!-- .LP -->
+<function>XMapSubwindows</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Unmapping_Windows">
+<title>Unmapping Windows</title>
+<!-- .XS -->
+<!-- (SN Unmapping Windows -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to unmap a window or all subwindows.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To unmap a window, use
+<function>XUnmapWindow</function>.
+<indexterm significance="preferred"><primary>XUnmapWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xunmapwindow'>
+<funcprototype>
+ <funcdef><function>XUnmapWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUnmapWindow</function>
+function unmaps the specified window and causes the X server to generate an
+<symbol>UnmapNotify</symbol>
+<indexterm><primary>UnmapNotify Event</primary></indexterm>
+<indexterm><primary>XUnmapWindow</primary></indexterm>
+event.
+If the specified window is already unmapped,
+<function>XUnmapWindow</function>
+has no effect.
+Normal exposure processing on formerly obscured windows is performed.
+Any child window will no longer be visible until another map call is
+made on the parent.
+In other words, the subwindows are still mapped but are not visible
+until the parent is mapped.
+Unmapping a window will generate
+<symbol>Expose</symbol>
+events on windows that were formerly obscured by it.
+</para>
+<para>
+<!-- .LP -->
+<function>XUnmapWindow</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To unmap all subwindows for a specified window, use
+<function>XUnmapSubwindows</function>.
+<indexterm significance="preferred"><primary>XUnmapSubwindows</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xunmapsubwindows'>
+<funcprototype>
+ <funcdef><function>XUnmapSubwindows</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUnmapSubwindows</function>
+function unmaps all subwindows for the specified window in bottom-to-top
+stacking order.
+It causes the X server to generate an
+<symbol>UnmapNotify</symbol>
+event on each subwindow and
+<symbol>Expose</symbol>
+events on formerly obscured windows.
+<indexterm><primary>UnmapNotify Event</primary></indexterm>
+Using this function is much more efficient than unmapping multiple windows
+one at a time because the server needs to perform much of the work
+only once, for all of the windows, rather than for each window.
+</para>
+<para>
+<!-- .LP -->
+<function>XUnmapSubwindows</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Configuring_Windows">
+<title>Configuring Windows</title>
+<!-- .XS -->
+<!-- (SN Configuring Windows -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+</para>
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to
+move a window, resize a window, move and resize a window, or
+change a window's border width.
+To change one of these parameters,
+set the appropriate member of the
+<structname>XWindowChanges</structname>
+structure and OR in the corresponding value mask in subsequent calls to
+<function>XConfigureWindow</function>.
+The symbols for the value mask bits and the
+<structname>XWindowChanges</structname>
+structure are:
+<!-- .sM -->
+</para>
+<para>
+<!-- .LP -->
+
+<literallayout class="monospaced">
+/* Configure window value mask bits */
+#define CWX (1&lt;&lt;0)
+#define CWY (1&lt;&lt;1)
+#define CWWidth (1&lt;&lt;2)
+#define CWHeight (1&lt;&lt;3)
+#define CWBorderWidth (1&lt;&lt;4)
+#define CWSibling (1&lt;&lt;5)
+#define CWStackMode (1&lt;&lt;6)
+</literallayout>
+
+<indexterm significance="preferred"><primary>XWindowChanges</primary></indexterm>
+<literallayout class="monospaced">
+/* Values */
+
+typedef struct {
+ int x, y;
+ int width, height;
+ int border_width;
+ Window sibling;
+ int stack_mode;
+} XWindowChanges;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The x and y members are used to set the window's x and y coordinates,
+which are relative to the parent's origin
+and indicate the position of the upper-left outer corner of the window.
+The width and height members are used to set the inside size of the window,
+not including the border, and must be nonzero, or a
+<errorname>BadValue</errorname>
+error results.
+Attempts to configure a root window have no effect.
+</para>
+<para>
+<!-- .LP -->
+The border_width member is used to set the width of the border in pixels.
+Note that setting just the border width leaves the outer-left corner of the window
+in a fixed position but moves the absolute position of the window's origin.
+If you attempt to set the border-width attribute of an
+<symbol>InputOnly</symbol>
+window nonzero, a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+The sibling member is used to set the sibling window for stacking operations.
+The stack_mode member is used to set how the window is to be restacked
+and can be set to
+<symbol>Above</symbol>,
+<symbol>Below</symbol>,
+<symbol>TopIf</symbol>,
+<symbol>BottomIf</symbol>,
+or
+<symbol>Opposite</symbol>.
+</para>
+<para>
+<!-- .LP -->
+If the override-redirect flag of the window is
+<symbol>False</symbol>
+and if some other client has selected
+<symbol>SubstructureRedirectMask</symbol>
+on the parent, the X server generates a
+<symbol>ConfigureRequest</symbol>
+event, and no further processing is performed.
+Otherwise,
+if some other client has selected
+<symbol>ResizeRedirectMask</symbol>
+on the window and the inside
+width or height of the window is being changed,
+a
+<symbol>ResizeRequest</symbol>
+event is generated, and the current inside width and height are
+used instead.
+Note that the override-redirect flag of the window has no effect
+on
+<symbol>ResizeRedirectMask</symbol>
+and that
+<symbol>SubstructureRedirectMask</symbol>
+on the parent has precedence over
+<symbol>ResizeRedirectMask</symbol>
+on the window.
+</para>
+<para>
+<!-- .LP -->
+When the geometry of the window is changed as specified,
+the window is restacked among siblings, and a
+<symbol>ConfigureNotify</symbol>
+event is generated if the state of the window actually changes.
+<symbol>GravityNotify</symbol>
+events are generated after
+<symbol>ConfigureNotify</symbol>
+events.
+If the inside width or height of the window has actually changed,
+children of the window are affected as specified.
+</para>
+<para>
+<!-- .LP -->
+If a window's size actually changes,
+the window's subwindows move according to their window gravity.
+Depending on the window's bit gravity,
+the contents of the window also may be moved (see section 3.2.3).
+</para>
+<para>
+<!-- .LP -->
+If regions of the window were obscured but now are not,
+exposure processing is performed on these formerly obscured windows,
+including the window itself and its inferiors.
+As a result of increasing the width or height,
+exposure processing is also performed on any new regions of the window
+and any regions where window contents are lost.
+</para>
+<para>
+<!-- .LP -->
+The restack check (specifically, the computation for
+<symbol>BottomIf</symbol>,
+<symbol>TopIf</symbol>,
+and
+<symbol>Opposite</symbol>)
+is performed with respect to the window's final size and position (as
+controlled by the other arguments of the request), not its initial position.
+If a sibling is specified without a stack_mode,
+a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+If a sibling and a stack_mode are specified,
+the window is restacked as follows:
+</para>
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <tbody>
+ <row>
+ <entry><symbol>Above</symbol></entry>
+ <entry>The window is placed just above the sibling.</entry>
+ </row>
+ <row>
+ <entry><symbol>Below</symbol></entry>
+ <entry>The window is placed just below the sibling.</entry>
+ </row>
+ <row>
+ <entry><symbol>TopIf</symbol></entry>
+ <entry>If the sibling occludes the window, the window is placed at the top of the stack.</entry>
+ </row>
+ <row>
+ <entry><symbol>BottomIf</symbol></entry>
+ <entry>If the window occludes the sibling, the window is placed at the bottom of the stack.</entry>
+ </row>
+ <row>
+ <entry><symbol>Opposite</symbol></entry>
+ <entry>
+If the sibling occludes the window, the window is placed at the top of the stack.
+If the window occludes the sibling,
+the window is placed at the bottom of the stack.
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+If a stack_mode is specified but no sibling is specified,
+the window is restacked as follows:
+</para>
+
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <tbody>
+ <row>
+ <entry><symbol>Above</symbol></entry>
+ <entry>The window is placed at the top of the stack.</entry>
+ </row>
+ <row>
+ <entry><symbol>Below</symbol></entry>
+ <entry>The window is placed at the bottom of the stack.</entry>
+ </row>
+ <row>
+ <entry><symbol>TopIf</symbol></entry>
+ <entry>
+If any sibling occludes the window, the window is placed at
+the top of the stack.
+ </entry>
+ </row>
+ <row>
+ <entry>
+If the window occludes any sibling, the window is placed at
+the bottom of the stack.
+ </entry>
+ </row>
+ <row>
+ <entry><symbol>Opposite</symbol></entry>
+ <entry>
+If any sibling occludes the window, the window
+is placed at the top of the stack.
+If the window occludes any sibling,
+the window is placed at the bottom of the stack.
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+Attempts to configure a root window have no effect.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To configure a window's size, location, stacking, or border, use
+<function>XConfigureWindow</function>.
+<indexterm significance="preferred"><primary>XConfigureWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xconfigurewindow'>
+<funcprototype>
+ <funcdef><function>XConfigureWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>unsignedint<parameter> value_mask</parameter></paramdef>
+ <paramdef>XWindowChanges<parameter> *values</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Wi to be reconfigured -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window (Wi.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which values are to be set using information in
+the values structure.
+This mask is the bitwise inclusive OR of the valid configure window values bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>values</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XWindowChanges</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XConfigureWindow</function>
+function uses the values specified in the
+<structname>XWindowChanges</structname>
+structure to reconfigure a window's size, position, border, and stacking order.
+Values not specified are taken from the existing geometry of the window.
+</para>
+<para>
+<!-- .LP -->
+If a sibling is specified without a stack_mode or if the window
+is not actually a sibling,
+a
+<errorname>BadMatch</errorname>
+error results.
+Note that the computations for
+<symbol>BottomIf</symbol>,
+<symbol>TopIf</symbol>,
+and
+<symbol>Opposite</symbol>
+are performed with respect to the window's final geometry (as controlled by the
+other arguments passed to
+<function>XConfigureWindow</function>),
+not its initial geometry.
+Any backing store contents of the window, its
+inferiors, and other newly visible windows are either discarded or
+changed to reflect the current screen contents
+(depending on the implementation).
+</para>
+<para>
+<!-- .LP -->
+<function>XConfigureWindow</function>
+can generate
+<errorname>BadMatch</errorname>,
+<errorname>BadValue</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To move a window without changing its size, use
+<function>XMoveWindow</function>.
+<indexterm significance="preferred"><primary>XMoveWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmovewindow'>
+<funcprototype>
+ <funcdef><function>XMoveWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Wi to be moved -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window (Wi.
+<!-- .ds Xy , which define the new location of the top-left pixel \ -->
+of the window's border or the window itself if it has no border
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XMoveWindow</function>
+function moves the specified window to the specified x and y coordinates,
+but it does not change the window's size, raise the window, or
+change the mapping state of the window.
+Moving a mapped window may or may not lose the window's contents
+depending on if the window is obscured by nonchildren
+and if no backing store exists.
+If the contents of the window are lost,
+the X server generates
+<symbol>Expose</symbol>
+events.
+Moving a mapped window generates
+<symbol>Expose</symbol>
+events on any formerly obscured windows.
+</para>
+<para>
+<!-- .LP -->
+If the override-redirect flag of the window is
+<symbol>False</symbol>
+and some
+other client has selected
+<symbol>SubstructureRedirectMask</symbol>
+on the parent, the X server generates a
+<symbol>ConfigureRequest</symbol>
+event, and no further processing is
+performed.
+Otherwise, the window is moved.
+</para>
+<para>
+<!-- .LP -->
+<function>XMoveWindow</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To change a window's size without changing the upper-left coordinate, use
+<function>XResizeWindow</function>.
+<indexterm significance="preferred"><primary>XResizeWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xresizewindow'>
+<funcprototype>
+ <funcdef><function>XResizeWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+<!-- .ds Wh , which are the interior dimensions of the window \ -->
+after the call completes
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XResizeWindow</function>
+function changes the inside dimensions of the specified window, not including
+its borders.
+This function does not change the window's upper-left coordinate or
+the origin and does not restack the window.
+Changing the size of a mapped window may lose its contents and generate
+<symbol>Expose</symbol>
+events.
+If a mapped window is made smaller,
+changing its size generates
+<symbol>Expose</symbol>
+events on windows that the mapped window formerly obscured.
+</para>
+<para>
+<!-- .LP -->
+If the override-redirect flag of the window is
+<symbol>False</symbol>
+and some
+other client has selected
+<symbol>SubstructureRedirectMask</symbol>
+on the parent, the X server generates a
+<symbol>ConfigureRequest</symbol>
+event, and no further processing is performed.
+If either width or height is zero,
+a
+<errorname>BadValue</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XResizeWindow</function>
+can generate
+<errorname>BadValue</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To change the size and location of a window, use
+<function>XMoveResizeWindow</function>.
+<indexterm significance="preferred"><primary>XMoveResizeWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmoveresizewindow'>
+<funcprototype>
+ <funcdef><function>XMoveResizeWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Wi to be reconfigured -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window (Wi.
+<!-- .ds Xy , which define the new position of the window relative to its parent -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+<!-- .ds Wh , which define the interior size of the window -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XMoveResizeWindow</function>
+function changes the size and location of the specified window
+without raising it.
+Moving and resizing a mapped window may generate an
+<symbol>Expose</symbol>
+event on the window.
+Depending on the new size and location parameters,
+moving and resizing a window may generate
+<symbol>Expose</symbol>
+events on windows that the window formerly obscured.
+</para>
+<para>
+<!-- .LP -->
+If the override-redirect flag of the window is
+<symbol>False</symbol>
+and some
+other client has selected
+<symbol>SubstructureRedirectMask</symbol>
+on the parent, the X server generates a
+<symbol>ConfigureRequest</symbol>
+event, and no further processing is performed.
+Otherwise, the window size and location are changed.
+</para>
+<para>
+<!-- .LP -->
+<function>XMoveResizeWindow</function>
+can generate
+<errorname>BadValue</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To change the border width of a given window, use
+<function>XSetWindowBorderWidth</function>.
+<indexterm significance="preferred"><primary>XSetWindowBorderWidth</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwindowborderwidth'>
+<funcprototype>
+ <funcdef><function>XSetWindowBorderWidth</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>unsignedint<parameter> width</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the width of the window border.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWindowBorderWidth</function>
+function sets the specified window's border width to the specified width.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetWindowBorderWidth</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Changing_Window_Stacking_Order">
+<title>Changing Window Stacking Order</title>
+<!-- .XS -->
+<!-- (SN Changing Window Stacking Order -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+</para>
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to raise, lower, circulate,
+or restack windows.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To raise a window so that no sibling window obscures it, use
+<function>XRaiseWindow</function>.
+<indexterm significance="preferred"><primary>XRaiseWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xraisewindow'>
+<funcprototype>
+ <funcdef><function>XRaiseWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XRaiseWindow</function>
+function
+raises the specified window to the top of the stack so that no sibling window
+obscures it.
+If the windows are regarded as overlapping sheets of paper stacked
+on a desk,
+then raising a window is analogous to moving the sheet to the top of
+the stack but leaving its x and y location on the desk constant.
+Raising a mapped window may generate
+<symbol>Expose</symbol>
+events for the window and any mapped subwindows that were formerly obscured.
+</para>
+<para>
+<!-- .LP -->
+If the override-redirect attribute of the window is
+<symbol>False</symbol>
+and some
+other client has selected
+<symbol>SubstructureRedirectMask</symbol>
+on the parent, the X server generates a
+<symbol>ConfigureRequest</symbol>
+event, and no processing is performed.
+Otherwise, the window is raised.
+</para>
+<para>
+<!-- .LP -->
+<function>XRaiseWindow</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To lower a window so that it does not obscure any sibling windows, use
+<function>XLowerWindow</function>.
+<indexterm significance="preferred"><primary>XLowerWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xlowerwindow'>
+<funcprototype>
+ <funcdef><function>XLowerWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XLowerWindow</function>
+function lowers the specified window to the bottom of the stack
+so that it does not obscure any sibling
+windows.
+If the windows are regarded as overlapping sheets of paper
+stacked on a desk, then lowering a window is analogous to moving the
+sheet to the bottom of the stack but leaving its x and y location on
+the desk constant.
+Lowering a mapped window will generate
+<symbol>Expose</symbol>
+events on any windows it formerly obscured.
+</para>
+<para>
+<!-- .LP -->
+If the override-redirect attribute of the window is
+<symbol>False</symbol>
+and some
+other client has selected
+<symbol>SubstructureRedirectMask</symbol>
+on the parent, the X server generates a
+<symbol>ConfigureRequest</symbol>
+event, and no processing is performed.
+Otherwise, the window is lowered to the bottom of the
+stack.
+</para>
+<para>
+<!-- .LP -->
+<function>XLowerWindow</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To circulate a subwindow up or down, use
+<function>XCirculateSubwindows</function>.
+<indexterm significance="preferred"><primary>XCirculateSubwindows</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcirculatesubwindows'>
+<funcprototype>
+ <funcdef><function>XCirculateSubwindows</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>int<parameter> direction</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>direction</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the direction (up or down) that you want to circulate
+the window.
+You can pass
+<symbol>RaiseLowest</symbol>
+or
+<symbol>LowerHighest</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCirculateSubwindows</function>
+function circulates children of the specified window in the specified
+direction.
+If you specify
+<symbol>RaiseLowest</symbol>,
+<function>XCirculateSubwindows</function>
+raises the lowest mapped child (if any) that is occluded
+by another child to the top of the stack.
+If you specify
+<symbol>LowerHighest</symbol>,
+<function>XCirculateSubwindows</function>
+lowers the highest mapped child (if any) that occludes another child
+to the bottom of the stack.
+Exposure processing is then performed on formerly obscured windows.
+If some other client has selected
+<symbol>SubstructureRedirectMask</symbol>
+on the window, the X server generates a
+<symbol>CirculateRequest</symbol>
+event, and no further processing is performed.
+If a child is actually restacked,
+the X server generates a
+<symbol>CirculateNotify</symbol>
+event.
+</para>
+<para>
+<!-- .LP -->
+<function>XCirculateSubwindows</function>
+can generate
+<errorname>BadValue</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To raise the lowest mapped child of a window that is partially or completely
+occluded by another child, use
+<function>XCirculateSubwindowsUp</function>.
+<indexterm significance="preferred"><primary>XCirculateSubwindowsUp</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcirculatesubwindowsup'>
+<funcprototype>
+ <funcdef><function>XCirculateSubwindowsUp</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCirculateSubwindowsUp</function>
+function raises the lowest mapped child of the specified window that
+is partially
+or completely
+occluded by another child.
+Completely unobscured children are not affected.
+This is a convenience function equivalent to
+<function>XCirculateSubwindows</function>
+with
+<symbol>RaiseLowest</symbol>
+specified.
+</para>
+<para>
+<!-- .LP -->
+<function>XCirculateSubwindowsUp</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To lower the highest mapped child of a window that partially or
+completely occludes another child, use
+<function>XCirculateSubwindowsDown</function>.
+<indexterm significance="preferred"><primary>XCirculateSubwindowsDown</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcirculatesubwindowsdown'>
+<funcprototype>
+ <funcdef><function>XCirculateSubwindowsDown</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCirculateSubwindowsDown</function>
+function lowers the highest mapped child of the specified window that partially
+or completely occludes another child.
+Completely unobscured children are not affected.
+This is a convenience function equivalent to
+<function>XCirculateSubwindows</function>
+with
+<symbol>LowerHighest</symbol>
+specified.
+</para>
+<para>
+<!-- .LP -->
+<function>XCirculateSubwindowsDown</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To restack a set of windows from top to bottom, use
+<function>XRestackWindows</function>.
+<indexterm significance="preferred"><primary>XRestackWindows</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrestackwindows'>
+<funcprototype>
+ <funcdef><function>XRestackWindows</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> windows[]</parameter></paramdef>
+ <paramdef>int<parameter> nwindows</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>windows</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array containing the windows to be restacked.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nwindows</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of windows to be restacked.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XRestackWindows</function>
+function restacks the windows in the order specified,
+from top to bottom.
+The stacking order of the first window in the windows array is unaffected,
+but the other windows in the array are stacked underneath the first window,
+in the order of the array.
+The stacking order of the other windows is not affected.
+For each window in the window array that is not a child of the specified window,
+a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+If the override-redirect attribute of a window is
+<symbol>False</symbol>
+and some
+other client has selected
+<symbol>SubstructureRedirectMask</symbol>
+on the parent, the X server generates
+<symbol>ConfigureRequest</symbol>
+events for each window whose override-redirect flag is not set,
+and no further processing is performed.
+Otherwise, the windows will be restacked in top-to-bottom order.
+</para>
+<para>
+<!-- .LP -->
+<function>XRestackWindows</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Changing_Window_Attributes">
+<title>Changing Window Attributes</title>
+<!-- .XS -->
+<!-- (SN Changing Window Attributes -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+</para>
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set window attributes.
+<function>XChangeWindowAttributes</function>
+is the more general function that allows you to set one or more window
+attributes provided by the
+<structname>XSetWindowAttributes</structname>
+structure.
+The other functions described in this section allow you to set one specific
+window attribute, such as a window's background.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To change one or more attributes for a given window, use
+<function>XChangeWindowAttributes</function>.
+<indexterm significance="preferred"><primary>XChangeWindowAttributes</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xchangewindowattributes'>
+<funcprototype>
+ <funcdef><function>XChangeWindowAttributes</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> valuemask</parameter></paramdef>
+ <paramdef>XSetWindowAttributes<parameter> *attributes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>valuemask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which window attributes are defined in the attributes
+argument.
+This mask is the bitwise inclusive OR of the valid attribute mask bits.
+If valuemask is zero,
+the attributes are ignored and are not referenced.
+The values and restrictions are
+the same as for
+<function>XCreateWindow</function>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+
+ </term>
+ <listitem>
+ <para>
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>attributes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the structure from which the values (as specified by the value mask)
+are to be taken.
+The value mask should have the appropriate bits
+set to indicate which attributes have been set in the structure
+(see section 3.2).
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Depending on the valuemask,
+the
+<function>XChangeWindowAttributes</function>
+function uses the window attributes in the
+<structname>XSetWindowAttributes</structname>
+structure to change the specified window attributes.
+Changing the background does not cause the window contents to be
+changed.
+To repaint the window and its background, use
+<function>XClearWindow</function>.
+Setting the border or changing the background such that the
+border tile origin changes causes the border to be repainted.
+Changing the background of a root window to
+<symbol>None</symbol>
+or
+<symbol>ParentRelative</symbol>
+restores the default background pixmap.
+Changing the border of a root window to
+<symbol>CopyFromParent</symbol>
+restores the default border pixmap.
+Changing the win-gravity does not affect the current position of the
+window.
+Changing the backing-store of an obscured window to
+<symbol>WhenMapped</symbol>
+or
+<symbol>Always</symbol>,
+or changing the backing-planes, backing-pixel, or
+save-under of a mapped window may have no immediate effect.
+Changing the colormap of a window (that is, defining a new map, not
+changing the contents of the existing map) generates a
+<symbol>ColormapNotify</symbol>
+event.
+Changing the colormap of a visible window may have no
+immediate effect on the screen because the map may not be installed
+(see
+<function>XInstallColormap</function>).
+Changing the cursor of a root window to
+<symbol>None</symbol>
+restores the default
+cursor.
+Whenever possible, you are encouraged to share colormaps.
+</para>
+<para>
+<!-- .LP -->
+Multiple clients can select input on the same window.
+Their event masks are maintained separately.
+When an event is generated,
+it is reported to all interested clients.
+However, only one client at a time can select for
+<symbol>SubstructureRedirectMask</symbol>,
+<symbol>ResizeRedirectMask</symbol>,
+and
+<symbol>ButtonPressMask</symbol>.
+If a client attempts to select any of these event masks
+and some other client has already selected one,
+a
+<errorname>BadAccess</errorname>
+error results.
+There is only one do-not-propagate-mask for a window,
+not one per client.
+</para>
+<para>
+<!-- .LP -->
+<function>XChangeWindowAttributes</function>
+can generate
+<errorname>BadAccess</errorname>,
+<errorname>BadColor</errorname>,
+<errorname>BadCursor</errorname>,
+<errorname>BadMatch</errorname>,
+<errorname>BadPixmap</errorname>,
+<errorname>BadValue</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the background of a window to a given pixel, use
+<function>XSetWindowBackground</function>.
+<indexterm significance="preferred"><primary>XSetWindowBackground</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwindowbackground'>
+<funcprototype>
+ <funcdef><function>XSetWindowBackground</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> background_pixel</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>background_pixel</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the pixel that is to be used for the background.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWindowBackground</function>
+function sets the background of the window to the specified pixel value.
+Changing the background does not cause the window contents to be changed.
+<function>XSetWindowBackground</function>
+uses a pixmap of undefined size filled with the pixel value you passed.
+If you try to change the background of an
+<symbol>InputOnly</symbol>
+window, a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetWindowBackground</function>
+can generate
+<errorname>BadMatch</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set the background of a window to a given pixmap, use
+<function>XSetWindowBackgroundPixmap</function>.
+<indexterm><primary>Window</primary><secondary>background</secondary></indexterm>
+<indexterm significance="preferred"><primary>XSetWindowBackgroundPixmap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwindowbackgroundpixmap'>
+<funcprototype>
+ <funcdef><function>XSetWindowBackgroundPixmap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Pixmap<parameter> background_pixmap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>background_pixmap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the background pixmap,
+<symbol>ParentRelative</symbol>,
+or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm><primary>Resource IDs</primary><secondary>freeing</secondary></indexterm>
+<indexterm><primary>Freeing</primary><secondary>resources</secondary></indexterm>
+The
+<function>XSetWindowBackgroundPixmap</function>
+function sets the background pixmap of the window to the specified pixmap.
+The background pixmap can immediately be freed if no further explicit
+references to it are to be made.
+If
+<symbol>ParentRelative</symbol>
+is specified,
+the background pixmap of the window's parent is used,
+or on the root window, the default background is restored.
+If you try to change the background of an
+<symbol>InputOnly</symbol>
+window, a
+<errorname>BadMatch</errorname>
+error results.
+If the background is set to
+<symbol>None</symbol>,
+the window has no defined background.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetWindowBackgroundPixmap</function>
+can generate
+<errorname>BadMatch</errorname>,
+<errorname>BadPixmap</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+<!-- .NT Note -->
+<function>XSetWindowBackground</function>
+and
+<function>XSetWindowBackgroundPixmap</function>
+do not change the current contents of the window.
+<!-- .NE -->
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To change and repaint a window's border to a given pixel, use
+<function>XSetWindowBorder</function>.
+<indexterm significance="preferred"><primary>XSetWindowBorder</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwindowborder'>
+<funcprototype>
+ <funcdef><function>XSetWindowBorder</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> border_pixel</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>border_pixel</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the entry in the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWindowBorder</function>
+function sets the border of the window to the pixel value you specify.
+If you attempt to perform this on an
+<symbol>InputOnly</symbol>
+window, a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetWindowBorder</function>
+can generate
+<errorname>BadMatch</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To change and repaint the border tile of a given window, use
+<function>XSetWindowBorderPixmap</function>.
+<indexterm significance="preferred"><primary>XSetWindowBorderPixmap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwindowborderpixmap'>
+<funcprototype>
+ <funcdef><function>XSetWindowBorderPixmap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Pixmap<parameter> border_pixmap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>border_pixmap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the border pixmap or
+<symbol>CopyFromParent</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWindowBorderPixmap</function>
+function sets the border pixmap of the window to the pixmap you specify.
+The border pixmap can be freed immediately if no further explicit
+references to it are to be made.
+If you specify
+<symbol>CopyFromParent</symbol>,
+a copy of the parent window's border pixmap is used.
+If you attempt to perform this on an
+<symbol>InputOnly</symbol>
+window, a
+<errorname>BadMatch</errorname>
+error results.
+<indexterm><primary>Resource IDs</primary><secondary>freeing</secondary></indexterm>
+<indexterm><primary>Freeing</primary><secondary>resources</secondary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<function>XSetWindowBorderPixmap</function>
+can generate
+<errorname>BadMatch</errorname>,
+<errorname>BadPixmap</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the colormap of a given window, use
+<function>XSetWindowColormap</function>.
+<indexterm significance="preferred"><primary>XSetWindowColormap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwindowcolormap'>
+<funcprototype>
+ <funcdef><function>XSetWindowColormap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWindowColormap</function>
+function sets the specified colormap of the specified window.
+The colormap must have the same visual type as the window,
+or a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetWindowColormap</function>
+can generate
+<errorname>BadColor</errorname>,
+<errorname>BadMatch</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To define which cursor will be used in a window, use
+<function>XDefineCursor</function>.
+<indexterm><primary>Window</primary><secondary>defining the cursor</secondary></indexterm>
+<indexterm significance="preferred"><primary>XDefineCursor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdefinecursor'>
+<funcprototype>
+ <funcdef><function>XDefineCursor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Cursor<parameter> cursor</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>cursor</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the cursor that is to be displayed or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If a cursor is set, it will be used when the pointer is in the window.
+If the cursor is
+<symbol>None</symbol>,
+it is equivalent to
+<function>XUndefineCursor</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XDefineCursor</function>
+can generate
+<errorname>BadCursor</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To undefine the cursor in a given window, use
+<function>XUndefineCursor</function>.
+<indexterm><primary>Window</primary><secondary>undefining the cursor</secondary></indexterm>
+<indexterm significance="preferred"><primary>XUndefineCursor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xundefinecursor'>
+<funcprototype>
+ <funcdef><function>XUndefineCursor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUndefineCursor</function>
+function undoes the effect of a previous
+<function>XDefineCursor</function>
+for this window.
+When the pointer is in the window,
+the parent's cursor will now be used.
+On the root window,
+the default cursor is restored.
+</para>
+<para>
+<!-- .LP -->
+<function>XUndefineCursor</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+<!-- .bp -->
+
+</para>
+</sect1>
+</chapter>
diff --git a/libX11/specs/libX11/CH04.xml b/libX11/specs/libX11/CH04.xml
index 8a3e8c535..d224216d3 100644
--- a/libX11/specs/libX11/CH04.xml
+++ b/libX11/specs/libX11/CH04.xml
@@ -40,7 +40,7 @@ a given window, use
<indexterm><primary>Parent Window</primary></indexterm>
<indexterm significance="preferred"><primary>XQueryTree</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xquerytree'>
<funcprototype>
<funcdef>Status <function>XQueryTree</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -147,7 +147,7 @@ To obtain the current attributes of a given window, use
<function>XGetWindowAttributes</function>.
<indexterm significance="preferred"><primary>XGetWindowAttributes</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xgetwindowattributes'>
<funcprototype>
<funcdef>Status <function>XGetWindowAttributes</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -372,7 +372,7 @@ To obtain the current geometry of a given drawable, use
<function>XGetGeometry</function>.
<indexterm significance="preferred"><primary>XGetGeometry</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xgetgeometry'>
<funcprototype>
<funcdef>Status <function>XGetGeometry</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -533,7 +533,7 @@ space of another window, use
<function>XTranslateCoordinates</function>.
<indexterm significance="preferred"><primary>XTranslateCoordinates</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xtranslatecoordinates'>
<funcprototype>
<funcdef>Bool <function>XTranslateCoordinates</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -667,7 +667,7 @@ or to determine the pointer coordinates relative to a specified window, use
<function>XQueryPointer</function>.
<indexterm significance="preferred"><primary>XQueryPointer</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xquerypointer'>
<funcprototype>
<funcdef>Bool <function>XQueryPointer</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1050,7 +1050,7 @@ To return an atom for a given name, use
<indexterm><primary>Atom</primary><secondary>interning</secondary></indexterm>
<indexterm significance="preferred"><primary>XInternAtom</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xinternatom'>
<funcprototype>
<funcdef>Atom <function>XInternAtom</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1132,7 +1132,7 @@ To return atoms for an array of names, use
<indexterm><primary>Atom</primary><secondary>interning</secondary></indexterm>
<indexterm significance="preferred"><primary>XInternAtoms</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xinternatoms'>
<funcprototype>
<funcdef>Status <function>XInternAtoms</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1233,7 +1233,7 @@ To return a name for a given atom identifier, use
<indexterm><primary>Atom</primary><secondary>getting name</secondary></indexterm>
<indexterm significance="preferred"><primary>XGetAtomName</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xgetatomname'>
<funcprototype>
<funcdef>char *<function>XGetAtomName</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1292,7 +1292,7 @@ To return the names for an array of atom identifiers, use
<indexterm><primary>Atom</primary><secondary>getting name</secondary></indexterm>
<indexterm significance="preferred"><primary>XGetAtomNames</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xgetatomnames'>
<funcprototype>
<funcdef>Status <function>XGetAtomNames</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1409,7 +1409,7 @@ To obtain the type, format, and value of a property of a given window, use
<!-- .LP -->
<indexterm significance="preferred"><primary>XGetWindowProperty</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xgetwindowproperty'>
<funcprototype>
<funcdef>int <function>XGetWindowProperty</function></funcdef>
<paramdef><parameter> display</parameter></paramdef>
@@ -1689,7 +1689,7 @@ To obtain a given window's property list, use
<indexterm><primary>Property</primary><secondary>listing</secondary></indexterm>
<indexterm significance="preferred"><primary>XListProperties</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xlistproperties'>
<funcprototype>
<funcdef>Atom *<function>XListProperties</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1762,7 +1762,7 @@ To change a property of a given window, use
<indexterm><primary>Property</primary><secondary>type</secondary></indexterm>
<indexterm significance="preferred"><primary>XChangeProperty</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xchangeproperty'>
<funcprototype>
<funcdef><function>XChangeProperty</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -1963,7 +1963,7 @@ To rotate a window's property list, use
<!-- .LP -->
<indexterm significance="preferred"><primary>XRotateWindowProperties</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xrotatewindowproperties'>
<funcprototype>
<funcdef><function>XRotateWindowProperties</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -2077,7 +2077,7 @@ To delete a property on a given window, use
<indexterm><primary>Property</primary><secondary>deleting</secondary></indexterm>
<indexterm significance="preferred"><primary>XDeleteProperty</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xdeleteproperty'>
<funcprototype>
<funcdef><function>XDeleteProperty</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -2200,7 +2200,7 @@ To set the selection owner, use
<indexterm><primary>Selection</primary><secondary>setting the owner</secondary></indexterm>
<indexterm significance="preferred"><primary>XSetSelectionOwner</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xsetselectionowner'>
<funcprototype>
<funcdef><function>XSetSelectionOwner</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -2323,7 +2323,7 @@ To return the selection owner, use
<indexterm><primary>Selection</primary><secondary>getting the owner</secondary></indexterm>
<indexterm significance="preferred"><primary>XGetSelectionOwner</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xgetselectionowner'>
<funcprototype>
<funcdef>Window <function>XGetSelectionOwner</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
@@ -2385,7 +2385,7 @@ To request conversion of a selection, use
<indexterm><primary>Selection</primary><secondary>converting</secondary></indexterm>
<indexterm significance="preferred"><primary>XConvertSelection</primary></indexterm>
<!-- .sM -->
-<funcsynopsis>
+<funcsynopsis id='xconvertselection'>
<funcprototype>
<funcdef><function>XConvertSelection</function></funcdef>
<paramdef>Display<parameter> *display</parameter></paramdef>
diff --git a/libX11/specs/libX11/CH05.xml b/libX11/specs/libX11/CH05.xml
index 08d78d666..3ad7076ea 100644
--- a/libX11/specs/libX11/CH05.xml
+++ b/libX11/specs/libX11/CH05.xml
@@ -1,818 +1,818 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<chapter id="pixmap_and_cursor_functions">
-<title>Pixmap and Cursor Functions</title>
-<sect1 id="Creating_and_Freeing_Pixmaps">
-<title>Creating and Freeing Pixmaps</title>
-<!-- .XS -->
-<!-- (SN Creating and Freeing Pixmaps -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Pixmaps can only be used on the screen on which they were created.
-Pixmaps are off-screen resources that are used for various operations,
-such as defining cursors as tiling patterns
-or as the source for certain raster operations.
-Most graphics requests can operate either on a window or on a pixmap.
-A bitmap is a single bit-plane pixmap.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create a pixmap of a given size, use
-<function>XCreatePixmap</function>.
-<indexterm significance="preferred"><primary>XCreatePixmap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Pixmap <function>XCreatePixmap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>unsignedint<parameter> depth</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which screen the pixmap is created on.
-<!-- .ds Wh , which define the dimensions of the pixmap -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>depth</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the depth of the pixmap.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreatePixmap</function>
-function creates a pixmap of the width, height, and depth you specified
-and returns a pixmap ID that identifies it.
-It is valid to pass an
-<symbol>InputOnly</symbol>
-window to the drawable argument.
-The width and height arguments must be nonzero,
-or a
-<errorname>BadValue</errorname>
-error results.
-The depth argument must be one of the depths supported by the screen
-of the specified drawable,
-or a
-<errorname>BadValue</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-The server uses the specified drawable to determine on which screen
-to create the pixmap.
-The pixmap can be used only on this screen
-and only with other drawables of the same depth (see
-<function>XCopyPlane</function>
-for an exception to this rule).
-The initial contents of the pixmap are undefined.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreatePixmap</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadDrawable</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To free all storage associated with a specified pixmap, use
-<function>XFreePixmap</function>.
-<indexterm significance="preferred"><primary>XFreePixmap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFreePixmap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Pixmap<parameter> pixmap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pixmap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the pixmap.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreePixmap</function>
-function first deletes the association between the pixmap ID and the pixmap.
-Then, the X server frees the pixmap storage when there are no references to it.
-The pixmap should never be referenced again.
-</para>
-<para>
-<!-- .LP -->
-<function>XFreePixmap</function>
-can generate a
-<errorname>BadPixmap</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Creating_Recoloring_and_Freeing_Cursors">
-<title>Creating, Recoloring, and Freeing Cursors</title>
-<!-- .XS -->
-<!-- (SN Creating, Recoloring, and Freeing Cursors -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Each window can have a different cursor defined for it.
-Whenever the pointer is in a visible window,
-it is set to the cursor defined for that window.
-If no cursor was defined for that window,
-the cursor is the one defined for the parent window.
-</para>
-<para>
-<!-- .LP -->
-From X's perspective,
-a cursor consists of a cursor source, mask, colors, and a hotspot.
-The mask pixmap determines the shape of the cursor and must be a depth
-of one.
-The source pixmap must have a depth of one,
-and the colors determine the colors of the source.
-The hotspot defines the point on the cursor that is reported
-when a pointer event occurs.
-There may be limitations imposed by the hardware on
-cursors as to size and whether a mask is implemented.
-<indexterm><primary>XQueryBestCursor</primary></indexterm>
-<function>XQueryBestCursor</function>
-can be used to find out what sizes are possible.
-There is a standard font for creating cursors, but
-Xlib provides functions that you can use to create cursors
-from an arbitrary font or from bitmaps.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create a cursor from the standard cursor font, use
-<function>XCreateFontCursor</function>.
-</para>
-<para>
-#include &lt;X11/cursorfont.h&gt;
-</para>
-
-<indexterm significance="preferred"><primary>XCreateFontCursor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Cursor <function>XCreateFontCursor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>unsignedint<parameter> shape</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>shape</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the shape of the cursor.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-X provides a set of standard cursor shapes in a special font named
-cursor.
-Applications are encouraged to use this interface for their cursors
-because the font can be customized for the individual display type.
-The shape argument specifies which glyph of the standard fonts
-to use.
-</para>
-<para>
-<!-- .LP -->
-The hotspot comes from the information stored in the cursor font.
-The initial colors of a cursor are a black foreground and a white
-background (see
-<function>XRecolorCursor</function>).
-For further information about cursor shapes,
-see appendix B.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreateFontCursor</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create a cursor from font glyphs, use
-<function>XCreateGlyphCursor</function>.
-<indexterm significance="preferred"><primary>XCreateGlyphCursor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Cursor <function>XCreateGlyphCursor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Fontsource_font,<parameter> mask_font</parameter></paramdef>
- <paramdef>unsignedintsource_char,<parameter> mask_char</parameter></paramdef>
- <paramdef>XColor<parameter> *foreground_color</parameter></paramdef>
- <paramdef>XColor<parameter> *background_color</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>source_font</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font for the source glyph.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>mask_font</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font for the mask glyph or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>source_char</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character glyph for the source.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>mask_char</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the glyph character for the mask.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>foreground_color</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the <acronym>RGB</acronym> values for the foreground of the source.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>background_color</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the <acronym>RGB</acronym> values for the background of the source.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreateGlyphCursor</function>
-function is similar to
-<function>XCreatePixmapCursor</function>
-except that the source and mask bitmaps are obtained from the specified
-font glyphs.
-The source_char must be a defined glyph in source_font,
-or a
-<errorname>BadValue</errorname>
-error results.
-If mask_font is given,
-mask_char must be a defined glyph in mask_font,
-or a
-<errorname>BadValue</errorname>
-error results.
-The mask_font and character are optional.
-The origins of the source_char and mask_char (if defined) glyphs are
-positioned coincidently and define the hotspot.
-The source_char and mask_char need not have the same bounding box metrics,
-and there is no restriction on the placement of the hotspot relative to the bounding
-boxes.
-If no mask_char is given, all pixels of the source are displayed.
-You can free the fonts immediately by calling
-<function>XFreeFont</function>
-if no further explicit references to them are to be made.
-</para>
-<para>
-<!-- .LP -->
-For 2-byte matrix fonts,
-the 16-bit value should be formed with the byte1
-member in the most significant byte and the byte2 member in the
-least significant byte.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreateGlyphCursor</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadFont</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create a cursor from two bitmaps,
-use
-<function>XCreatePixmapCursor</function>.
-<indexterm significance="preferred"><primary>XCreatePixmapCursor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Cursor <function>XCreatePixmapCursor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Pixmap<parameter> source</parameter></paramdef>
- <paramdef>Pixmap<parameter> mask</parameter></paramdef>
- <paramdef>XColor<parameter> *foreground_color</parameter></paramdef>
- <paramdef>XColor<parameter> *background_color</parameter></paramdef>
- <paramdef>unsignedintx,<parameter> y</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>source</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the shape of the source cursor.
-<!-- .\" *** JIM: NEED TO CHECK THIS. *** -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the cursor's source bits to be displayed or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>foreground_color</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the <acronym>RGB</acronym> values for the foreground of the source.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>background_color</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the <acronym>RGB</acronym> values for the background of the source.
-<!-- .ds Xy , which indicate the hotspot relative to the source's origin -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreatePixmapCursor</function>
-function creates a cursor and returns the cursor ID associated with it.
-The foreground and background <acronym>RGB</acronym> values must be specified using
-foreground_color and background_color,
-even if the X server only has a
-<symbol>StaticGray</symbol>
-or
-<symbol>GrayScale</symbol>
-screen.
-The foreground color is used for the pixels set to 1 in the
-source, and the background color is used for the pixels set to 0.
-Both source and mask, if specified, must have depth one (or a
-<errorname>BadMatch</errorname>
-error results) but can have any root.
-The mask argument defines the shape of the cursor.
-The pixels set to 1 in the mask define which source pixels are displayed,
-and the pixels set to 0 define which pixels are ignored.
-If no mask is given,
-all pixels of the source are displayed.
-The mask, if present, must be the same size as the pixmap defined by the
-source argument, or a
-<errorname>BadMatch</errorname>
-error results.
-The hotspot must be a point within the source,
-or a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-The components of the cursor can be transformed arbitrarily to meet
-display limitations.
-The pixmaps can be freed immediately if no further explicit references
-to them are to be made.
-Subsequent drawing in the source or mask pixmap has an undefined effect on the
-cursor.
-The X server might or might not make a copy of the pixmap.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreatePixmapCursor</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadPixmap</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To determine useful cursor sizes, use
-<function>XQueryBestCursor</function>.
-<indexterm significance="preferred"><primary>XQueryBestCursor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XQueryBestCursor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Dr , which indicates the screen -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable(Dr.
-<!-- .ds Wh \ of the cursor that you want the size information for -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the best width and height that is closest to the specified width
-and height.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Some displays allow larger cursors than other displays.
-The
-<function>XQueryBestCursor</function>
-function provides a way to find out what size cursors are actually
-possible on the display.
-<indexterm ><primary>Cursor</primary><secondary>limitations</secondary></indexterm>
-It returns the largest size that can be displayed.
-Applications should be prepared to use smaller cursors on displays that
-cannot support large ones.
-</para>
-<para>
-<!-- .LP -->
-<function>XQueryBestCursor</function>
-can generate a
-<errorname>BadDrawable</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To change the color of a given cursor, use
-<function>XRecolorCursor</function>.
-<indexterm significance="preferred"><primary>XRecolorCursor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XRecolorCursor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Cursor<parameter> cursor</parameter></paramdef>
- <paramdef>XColor*foreground_color,<parameter> *background_color</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>cursor</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the cursor.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>foreground_color</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the <acronym>RGB</acronym> values for the foreground of the source.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>background_color</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the <acronym>RGB</acronym> values for the background of the source.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XRecolorCursor</function>
-function changes the color of the specified cursor, and
-if the cursor is being displayed on a screen,
-the change is visible immediately.
-The pixel members of the
-<structname>XColor</structname>
-structures are ignored; only the <acronym>RGB</acronym> values are used.
-</para>
-<para>
-<!-- .LP -->
-<function>XRecolorCursor</function>
-can generate a
-<errorname>BadCursor</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To free (destroy) a given cursor, use
-<function>XFreeCursor</function>.
-<indexterm significance="preferred"><primary>XFreeCursor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFreeCursor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Cursor<parameter> cursor</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>cursor</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the cursor.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreeCursor</function>
-function deletes the association between the cursor resource ID
-and the specified cursor.
-The cursor storage is freed when no other resource references it.
-The specified cursor ID should not be referred to again.
-</para>
-<para>
-<!-- .LP -->
-<function>XFreeCursor</function>
-can generate a
-<errorname>BadCursor</errorname>
-error.
-<!-- .bp -->
-
-</para>
-</sect1>
-</chapter>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<chapter id="pixmap_and_cursor_functions">
+<title>Pixmap and Cursor Functions</title>
+<sect1 id="Creating_and_Freeing_Pixmaps">
+<title>Creating and Freeing Pixmaps</title>
+<!-- .XS -->
+<!-- (SN Creating and Freeing Pixmaps -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Pixmaps can only be used on the screen on which they were created.
+Pixmaps are off-screen resources that are used for various operations,
+such as defining cursors as tiling patterns
+or as the source for certain raster operations.
+Most graphics requests can operate either on a window or on a pixmap.
+A bitmap is a single bit-plane pixmap.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create a pixmap of a given size, use
+<function>XCreatePixmap</function>.
+<indexterm significance="preferred"><primary>XCreatePixmap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreatepixmap'>
+<funcprototype>
+ <funcdef>Pixmap <function>XCreatePixmap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>unsignedint<parameter> depth</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which screen the pixmap is created on.
+<!-- .ds Wh , which define the dimensions of the pixmap -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>depth</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the depth of the pixmap.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreatePixmap</function>
+function creates a pixmap of the width, height, and depth you specified
+and returns a pixmap ID that identifies it.
+It is valid to pass an
+<symbol>InputOnly</symbol>
+window to the drawable argument.
+The width and height arguments must be nonzero,
+or a
+<errorname>BadValue</errorname>
+error results.
+The depth argument must be one of the depths supported by the screen
+of the specified drawable,
+or a
+<errorname>BadValue</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+The server uses the specified drawable to determine on which screen
+to create the pixmap.
+The pixmap can be used only on this screen
+and only with other drawables of the same depth (see
+<function>XCopyPlane</function>
+for an exception to this rule).
+The initial contents of the pixmap are undefined.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreatePixmap</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadDrawable</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To free all storage associated with a specified pixmap, use
+<function>XFreePixmap</function>.
+<indexterm significance="preferred"><primary>XFreePixmap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfreepixmap'>
+<funcprototype>
+ <funcdef><function>XFreePixmap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Pixmap<parameter> pixmap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pixmap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the pixmap.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreePixmap</function>
+function first deletes the association between the pixmap ID and the pixmap.
+Then, the X server frees the pixmap storage when there are no references to it.
+The pixmap should never be referenced again.
+</para>
+<para>
+<!-- .LP -->
+<function>XFreePixmap</function>
+can generate a
+<errorname>BadPixmap</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Creating_Recoloring_and_Freeing_Cursors">
+<title>Creating, Recoloring, and Freeing Cursors</title>
+<!-- .XS -->
+<!-- (SN Creating, Recoloring, and Freeing Cursors -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Each window can have a different cursor defined for it.
+Whenever the pointer is in a visible window,
+it is set to the cursor defined for that window.
+If no cursor was defined for that window,
+the cursor is the one defined for the parent window.
+</para>
+<para>
+<!-- .LP -->
+From X's perspective,
+a cursor consists of a cursor source, mask, colors, and a hotspot.
+The mask pixmap determines the shape of the cursor and must be a depth
+of one.
+The source pixmap must have a depth of one,
+and the colors determine the colors of the source.
+The hotspot defines the point on the cursor that is reported
+when a pointer event occurs.
+There may be limitations imposed by the hardware on
+cursors as to size and whether a mask is implemented.
+<indexterm><primary>XQueryBestCursor</primary></indexterm>
+<function>XQueryBestCursor</function>
+can be used to find out what sizes are possible.
+There is a standard font for creating cursors, but
+Xlib provides functions that you can use to create cursors
+from an arbitrary font or from bitmaps.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create a cursor from the standard cursor font, use
+<function>XCreateFontCursor</function>.
+</para>
+<para>
+#include &lt;X11/cursorfont.h&gt;
+</para>
+
+<indexterm significance="preferred"><primary>XCreateFontCursor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreatefontcursor'>
+<funcprototype>
+ <funcdef>Cursor <function>XCreateFontCursor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>unsignedint<parameter> shape</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>shape</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the shape of the cursor.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+X provides a set of standard cursor shapes in a special font named
+cursor.
+Applications are encouraged to use this interface for their cursors
+because the font can be customized for the individual display type.
+The shape argument specifies which glyph of the standard fonts
+to use.
+</para>
+<para>
+<!-- .LP -->
+The hotspot comes from the information stored in the cursor font.
+The initial colors of a cursor are a black foreground and a white
+background (see
+<function>XRecolorCursor</function>).
+For further information about cursor shapes,
+see appendix B.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreateFontCursor</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create a cursor from font glyphs, use
+<function>XCreateGlyphCursor</function>.
+<indexterm significance="preferred"><primary>XCreateGlyphCursor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreateglyphcursor'>
+<funcprototype>
+ <funcdef>Cursor <function>XCreateGlyphCursor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Fontsource_font,<parameter> mask_font</parameter></paramdef>
+ <paramdef>unsignedintsource_char,<parameter> mask_char</parameter></paramdef>
+ <paramdef>XColor<parameter> *foreground_color</parameter></paramdef>
+ <paramdef>XColor<parameter> *background_color</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>source_font</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font for the source glyph.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>mask_font</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font for the mask glyph or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>source_char</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character glyph for the source.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>mask_char</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the glyph character for the mask.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>foreground_color</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the <acronym>RGB</acronym> values for the foreground of the source.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>background_color</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the <acronym>RGB</acronym> values for the background of the source.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreateGlyphCursor</function>
+function is similar to
+<function>XCreatePixmapCursor</function>
+except that the source and mask bitmaps are obtained from the specified
+font glyphs.
+The source_char must be a defined glyph in source_font,
+or a
+<errorname>BadValue</errorname>
+error results.
+If mask_font is given,
+mask_char must be a defined glyph in mask_font,
+or a
+<errorname>BadValue</errorname>
+error results.
+The mask_font and character are optional.
+The origins of the source_char and mask_char (if defined) glyphs are
+positioned coincidently and define the hotspot.
+The source_char and mask_char need not have the same bounding box metrics,
+and there is no restriction on the placement of the hotspot relative to the bounding
+boxes.
+If no mask_char is given, all pixels of the source are displayed.
+You can free the fonts immediately by calling
+<function>XFreeFont</function>
+if no further explicit references to them are to be made.
+</para>
+<para>
+<!-- .LP -->
+For 2-byte matrix fonts,
+the 16-bit value should be formed with the byte1
+member in the most significant byte and the byte2 member in the
+least significant byte.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreateGlyphCursor</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadFont</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create a cursor from two bitmaps,
+use
+<function>XCreatePixmapCursor</function>.
+<indexterm significance="preferred"><primary>XCreatePixmapCursor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreatepixmapcursor'>
+<funcprototype>
+ <funcdef>Cursor <function>XCreatePixmapCursor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Pixmap<parameter> source</parameter></paramdef>
+ <paramdef>Pixmap<parameter> mask</parameter></paramdef>
+ <paramdef>XColor<parameter> *foreground_color</parameter></paramdef>
+ <paramdef>XColor<parameter> *background_color</parameter></paramdef>
+ <paramdef>unsignedintx,<parameter> y</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>source</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the shape of the source cursor.
+<!-- .\" *** JIM: NEED TO CHECK THIS. *** -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the cursor's source bits to be displayed or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>foreground_color</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the <acronym>RGB</acronym> values for the foreground of the source.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>background_color</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the <acronym>RGB</acronym> values for the background of the source.
+<!-- .ds Xy , which indicate the hotspot relative to the source's origin -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreatePixmapCursor</function>
+function creates a cursor and returns the cursor ID associated with it.
+The foreground and background <acronym>RGB</acronym> values must be specified using
+foreground_color and background_color,
+even if the X server only has a
+<symbol>StaticGray</symbol>
+or
+<symbol>GrayScale</symbol>
+screen.
+The foreground color is used for the pixels set to 1 in the
+source, and the background color is used for the pixels set to 0.
+Both source and mask, if specified, must have depth one (or a
+<errorname>BadMatch</errorname>
+error results) but can have any root.
+The mask argument defines the shape of the cursor.
+The pixels set to 1 in the mask define which source pixels are displayed,
+and the pixels set to 0 define which pixels are ignored.
+If no mask is given,
+all pixels of the source are displayed.
+The mask, if present, must be the same size as the pixmap defined by the
+source argument, or a
+<errorname>BadMatch</errorname>
+error results.
+The hotspot must be a point within the source,
+or a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+The components of the cursor can be transformed arbitrarily to meet
+display limitations.
+The pixmaps can be freed immediately if no further explicit references
+to them are to be made.
+Subsequent drawing in the source or mask pixmap has an undefined effect on the
+cursor.
+The X server might or might not make a copy of the pixmap.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreatePixmapCursor</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadPixmap</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To determine useful cursor sizes, use
+<function>XQueryBestCursor</function>.
+<indexterm significance="preferred"><primary>XQueryBestCursor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xquerybestcursor'>
+<funcprototype>
+ <funcdef>Status <function>XQueryBestCursor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Dr , which indicates the screen -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable(Dr.
+<!-- .ds Wh \ of the cursor that you want the size information for -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the best width and height that is closest to the specified width
+and height.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Some displays allow larger cursors than other displays.
+The
+<function>XQueryBestCursor</function>
+function provides a way to find out what size cursors are actually
+possible on the display.
+<indexterm ><primary>Cursor</primary><secondary>limitations</secondary></indexterm>
+It returns the largest size that can be displayed.
+Applications should be prepared to use smaller cursors on displays that
+cannot support large ones.
+</para>
+<para>
+<!-- .LP -->
+<function>XQueryBestCursor</function>
+can generate a
+<errorname>BadDrawable</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To change the color of a given cursor, use
+<function>XRecolorCursor</function>.
+<indexterm significance="preferred"><primary>XRecolorCursor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrecolorcursor'>
+<funcprototype>
+ <funcdef><function>XRecolorCursor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Cursor<parameter> cursor</parameter></paramdef>
+ <paramdef>XColor*foreground_color,<parameter> *background_color</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>cursor</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the cursor.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>foreground_color</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the <acronym>RGB</acronym> values for the foreground of the source.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>background_color</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the <acronym>RGB</acronym> values for the background of the source.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XRecolorCursor</function>
+function changes the color of the specified cursor, and
+if the cursor is being displayed on a screen,
+the change is visible immediately.
+The pixel members of the
+<structname>XColor</structname>
+structures are ignored; only the <acronym>RGB</acronym> values are used.
+</para>
+<para>
+<!-- .LP -->
+<function>XRecolorCursor</function>
+can generate a
+<errorname>BadCursor</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To free (destroy) a given cursor, use
+<function>XFreeCursor</function>.
+<indexterm significance="preferred"><primary>XFreeCursor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfreecursor'>
+<funcprototype>
+ <funcdef><function>XFreeCursor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Cursor<parameter> cursor</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>cursor</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the cursor.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreeCursor</function>
+function deletes the association between the cursor resource ID
+and the specified cursor.
+The cursor storage is freed when no other resource references it.
+The specified cursor ID should not be referred to again.
+</para>
+<para>
+<!-- .LP -->
+<function>XFreeCursor</function>
+can generate a
+<errorname>BadCursor</errorname>
+error.
+<!-- .bp -->
+
+</para>
+</sect1>
+</chapter>
diff --git a/libX11/specs/libX11/CH06.xml b/libX11/specs/libX11/CH06.xml
index a8224d8fc..ab5cec031 100644
--- a/libX11/specs/libX11/CH06.xml
+++ b/libX11/specs/libX11/CH06.xml
@@ -1,7448 +1,7448 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<chapter id="color_management_functions">
-<title>Color Management Functions</title>
-<!-- .sp 2 -->
-<!-- .nr H1 6 -->
-<!-- .nr H2 0 -->
-<!-- .nr H3 0 -->
-<!-- .nr H4 0 -->
-<!-- .nr H5 0 -->
-<!-- .na -->
-<para>
-<!-- .LP -->
-<!-- .XS -->
-<!-- Chapter 6: Color Management Functions -->
-<!-- .XE -->
-Each X window always has an associated colormap that
-provides a level of indirection between pixel values and colors displayed
-on the screen.
-Xlib provides functions that you can use to manipulate a colormap.
-The X protocol defines colors using values in the <acronym>RGB</acronym> color space.
-The <acronym>RGB</acronym> color space is device dependent;
-rendering an <acronym>RGB</acronym> value on differing output devices typically results
-in different colors.
-Xlib also provides a means for clients to specify color using
-device-independent color spaces for consistent results across devices.
-Xlib supports device-independent color spaces derivable from the <acronym>CIE</acronym> XYZ
-color space.
-This includes the <acronym>CIE</acronym> XYZ, xyY, L*u*v*, and L*a*b* color spaces as well as
-the TekHVC color space.
-</para>
-<para>
-<!-- .LP -->
-This chapter discusses how to:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Create, copy, and destroy a colormap
- </para>
- </listitem>
- <listitem>
- <para>
-Specify colors by name or value
- </para>
- </listitem>
- <listitem>
- <para>
-Allocate, modify, and free color cells
- </para>
- </listitem>
- <listitem>
- <para>
-Read entries in a colormap
- </para>
- </listitem>
- <listitem>
- <para>
-Convert between color spaces
- </para>
- </listitem>
- <listitem>
- <para>
-Control aspects of color conversion
- </para>
- </listitem>
- <listitem>
- <para>
-Query the color gamut of a screen
- </para>
- </listitem>
- <listitem>
- <para>
-Add new color spaces
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-All functions, types, and symbols in this chapter with the prefix ``Xcms''
-are defined in
-<filename class="headerfile">&lt;X11/Xcms.h&gt;</filename>.
-<indexterm type="file"><primary><filename class="headerfile">X11/Xcms.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xcms.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xcms.h&gt;</filename></secondary></indexterm>
-The remaining functions and types are defined in
-<filename class="headerfile">&lt;X11/Xlib.h&gt;</filename>.
-<indexterm type="file"><primary><filename class="headerfile">X11/Xlib.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xlib.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xlib.h&gt;</filename></secondary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-Functions in this chapter manipulate the representation of color on the
-screen.
-For each possible value that a pixel can take in a window,
-there is a color cell in the colormap.
-For example,
-if a window is 4 bits deep, pixel values 0 through 15 are defined.
-A colormap is a collection of color cells.
-A color cell consists of a triple of red, green, and blue (<acronym>RGB</acronym>) values.
-The hardware imposes limits on the number of significant
-bits in these values.
-As each pixel is read out of display memory, the pixel
-is looked up in a colormap.
-The <acronym>RGB</acronym> value of the cell determines what color is displayed on the screen.
-On a grayscale display with a black-and-white monitor,
-the values are combined to determine the brightness on the screen.
-</para>
-<para>
-<!-- .LP -->
-Typically, an application allocates color cells or sets of color cells
-to obtain the desired colors.
-The client can allocate read-only cells.
-In which case,
-the pixel values for these colors can be shared among multiple applications,
-and the <acronym>RGB</acronym> value of the cell cannot be changed.
-If the client allocates read/write cells,
-they are exclusively owned by the client,
-and the color associated with the pixel value can be changed at will.
-Cells must be allocated (and, if read/write, initialized with an <acronym>RGB</acronym> value)
-by a client to obtain desired colors.
-The use of pixel value for an
-unallocated cell results in an undefined color.
-</para>
-<para>
-<!-- .LP -->
-Because colormaps are associated with windows, X supports displays
-with multiple colormaps and, indeed, different types of colormaps.
-If there are insufficient colormap resources in the display,
-some windows will display in their true colors, and others
-will display with incorrect colors.
-A window manager usually controls which windows are displayed
-in their true colors if more than one colormap is required for
-the color resources the applications are using.
-At any time, there is a set of installed colormaps for a screen.
-Windows using one of the installed colormaps display with true colors, and
-windows using other colormaps generally display with incorrect colors.
-You can control the set of installed colormaps by using
-<function>XInstallColormap</function>
-and
-<function>XUninstallColormap</function>.
-</para>
-<para>
-<!-- .LP -->
-Colormaps are local to a particular screen.
-Screens always have a default colormap,
-and programs typically allocate cells out of this colormap.
-Generally, you should not write applications that monopolize
-color resources.
-Although some hardware supports multiple colormaps installed at one time,
-many of the hardware displays
-built today support only a single installed colormap, so the primitives
-are written to encourage sharing of colormap entries between applications.
-</para>
-<para>
-<!-- .LP -->
-The
-<function>DefaultColormap</function>
-macro returns the default colormap.
-The
-<function>DefaultVisual</function>
-macro
-returns the default visual type for the specified screen.
-<indexterm><primary>Color map</primary></indexterm>
-Possible visual types are
-<symbol>StaticGray</symbol>,
-<symbol>GrayScale</symbol>,
-<symbol>StaticColor</symbol>,
-<symbol>PseudoColor</symbol>,
-<symbol>TrueColor</symbol>,
-or
-<symbol>DirectColor</symbol>
-(see section 3.1).
-</para>
-<sect1 id="Color_Structures">
-<title>Color Structures</title>
-<!-- .XS -->
-<!-- (SN Color Structures -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Functions that operate only on <acronym>RGB</acronym> color space values use an
-<structname>XColor</structname>
-structure, which contains:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XColor</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- unsigned long pixel; /* pixel value */
- unsigned short red, green, blue; /* rgb values */
- char flags; /* DoRed, DoGreen, DoBlue */
- char pad;
-} XColor;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The red, green, and blue values are always in the range 0 to 65535
-inclusive, independent of the number of bits actually used in the
-display hardware.
-The server scales these values down to the range used by the hardware.
-Black is represented by (0,0,0),
-and white is represented by (65535,65535,65535).
-<indexterm><primary>Color</primary></indexterm>
-In some functions,
-the flags member controls which of the red, green, and blue members is used
-and can be the inclusive OR of zero or more of
-<symbol>DoRed</symbol>,
-<symbol>DoGreen</symbol>,
-and
-<symbol>DoBlue</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-Functions that operate on all color space values use an
-<structname>XcmsColor</structname>
-structure.
-This structure contains a union of substructures,
-each supporting color specification encoding for a particular color space.
-Like the
-<structname>XColor</structname>
-structure, the
-<structname>XcmsColor</structname>
-structure contains pixel
-and color specification information (the spec member in the
-<structname>XcmsColor</structname>
-structure).
-<indexterm significance="preferred"><primary>XcmsColor</primary></indexterm>
-<!-- .sM -->
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 1i 2.5i -->
-<!-- .ta .5i 1i 2.5i -->
-typedef unsigned long XcmsColorFormat; /* Color Specification Format */
-
-typedef struct {
- union {
- XcmsRGB RGB;
- XcmsRGBi RGBi;
- XcmsCIEXYZ CIEXYZ;
- XcmsCIEuvY CIEuvY;
- XcmsCIExyY CIExyY;
- XcmsCIELab CIELab;
- XcmsCIELuv CIELuv;
- XcmsTekHVC TekHVC;
- XcmsPad Pad;
- } spec;
- unsigned long pixel;
- XcmsColorFormat format;
-} XcmsColor; /* Xcms Color Structure */
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Because the color specification can be encoded for the various color spaces,
-encoding for the spec member is identified by the format member,
-which is of type
-<type>XcmsColorFormat</type>.
-The following macros define standard formats.
-<!-- .sM -->
-</para>
-
-<literallayout class="monospaced">
-#define XcmsUndefinedFormat 0x00000000
-#define XcmsCIEXYZFormat 0x00000001 /* CIE XYZ */
-#define XcmsCIEuvYFormat 0x00000002 /* CIE u'v'Y */
-#define XcmsCIExyYFormat 0x00000003 /* CIE xyY */
-#define XcmsCIELabFormat 0x00000004 /* CIE L*a*b* */
-#define XcmsCIELuvFormat 0x00000005 /* CIE L*u*v* */
-#define XcmsTekHVCFormat 0x00000006 /* TekHVC */
-#define XcmsRGBFormat 0x80000000 /* RGB Device */
-#define XcmsRGBiFormat 0x80000001 /* RGB Intensity */
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Formats for device-independent color spaces are
-distinguishable from those for device-dependent spaces by the 32nd bit.
-If this bit is set,
-it indicates that the color specification is in a device-dependent form;
-otherwise, it is in a device-independent form.
-If the 31st bit is set,
-this indicates that the color space has been added to Xlib at run time
-(see section 6.12.4).
-The format value for a color space added at run time may be different each
-time the program is executed.
-If references to such a color space must be made outside the client
-(for example, storing a color specification in a file),
-then reference should be made by color space string prefix
-(see
-<function>XcmsFormatOfPrefix</function>
-and
-<function>XcmsPrefixOfFormat</function>).
-</para>
-<para>
-<!-- .LP -->
-Data types that describe the color specification encoding for the various
-color spaces are defined as follows:
-<!-- .sM -->
-<indexterm significance="preferred"><primary>XcmsRGB</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef double XcmsFloat;
-
-typedef struct {
- unsigned short red; /* 0x0000 to 0xffff */
- unsigned short green; /* 0x0000 to 0xffff */
- unsigned short blue; /* 0x0000 to 0xffff */
-} XcmsRGB; /* RGB Device */
-</literallayout>
-<indexterm significance="preferred"><primary>XcmsRGBi</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- XcmsFloat red; /* 0.0 to 1.0 */
- XcmsFloat green; /* 0.0 to 1.0 */
- XcmsFloat blue; /* 0.0 to 1.0 */
-} XcmsRGBi; /* RGB Intensity */
-</literallayout>
-<indexterm significance="preferred"><primary>XcmsCIEXYZ</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- XcmsFloat X;
- XcmsFloat Y; /* 0.0 to 1.0 */
- XcmsFloat Z;
-} XcmsCIEXYZ; /* CIE XYZ */
-</literallayout>
-<indexterm significance="preferred"><primary>XcmsCIEuvY</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- XcmsFloat u_prime; /* 0.0 to ~0.6 */
- XcmsFloat v_prime; /* 0.0 to ~0.6 */
- XcmsFloat Y; /* 0.0 to 1.0 */
-} XcmsCIEuvY; /* CIE u'v'Y */
-</literallayout>
-<indexterm significance="preferred"><primary>XcmsCIExyY</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- XcmsFloat x; /* 0.0 to ~.75 */
- XcmsFloat y; /* 0.0 to ~.85 */
- XcmsFloat Y; /* 0.0 to 1.0 */
-} XcmsCIExyY; /* CIE xyY */
-</literallayout>
-<indexterm significance="preferred"><primary>XcmsCIELab</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- XcmsFloat L_star; /* 0.0 to 100.0 */
- XcmsFloat a_star;
- XcmsFloat b_star;
-} XcmsCIELab; /* CIE L*a*b* */
-</literallayout>
-<indexterm significance="preferred"><primary>XcmsCIELuv</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- XcmsFloat L_star; /* 0.0 to 100.0 */
- XcmsFloat u_star;
- XcmsFloat v_star;
-} XcmsCIELuv; /* CIE L*u*v* */
-</literallayout>
-<indexterm significance="preferred"><primary>XcmsTekHVC</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- XcmsFloat H; /* 0.0 to 360.0 */
- XcmsFloat V; /* 0.0 to 100.0 */
- XcmsFloat C; /* 0.0 to 100.0 */
-} XcmsTekHVC; /* TekHVC */
-</literallayout>
-<indexterm significance="preferred"><primary>XcmsPad</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- XcmsFloat pad0;
- XcmsFloat pad1;
- XcmsFloat pad2;
- XcmsFloat pad3;
-} XcmsPad; /* four doubles */
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The device-dependent formats provided allow color specification in:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-<acronym>RGB</acronym> Intensity
-(<structname>XcmsRGBi</structname>)
- </para>
- </listitem>
- <listitem>
- <para>
-Red, green, and blue linear intensity values,
-floating-point values from 0.0 to 1.0,
-where 1.0 indicates full intensity, 0.5 half intensity, and so on.
- </para>
- </listitem>
- <listitem>
- <para>
-<acronym>RGB</acronym> Device
-(<structname>XcmsRGB</structname>)
- </para>
- </listitem>
- <listitem>
- <para>
-Red, green, and blue values appropriate for the specified output device.
-<structname>XcmsRGB</structname>
-values are of type unsigned short,
-scaled from 0 to 65535 inclusive,
-and are interchangeable with the red, green, and blue values in an
-<structname>XColor</structname>
-structure.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-It is important to note that <acronym>RGB</acronym> Intensity values are not gamma corrected
-values.
-In contrast,
-<acronym>RGB</acronym> Device values generated as a result of converting color specifications
-are always gamma corrected, and
-<acronym>RGB</acronym> Device values acquired as a result of querying a colormap
-or passed in by the client are assumed by Xlib to be gamma corrected.
-The term <emphasis remap='I'><acronym>RGB</acronym> value</emphasis> in this manual always refers to an <acronym>RGB</acronym> Device value.
-</para>
-</sect1>
-<sect1 id="Color_Strings">
-<title>Color Strings</title>
-<!-- .XS -->
-<!-- (SN Color Strings -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides a mechanism for using string names for colors.
-A color string may either contain an abstract color name
-or a numerical color specification.
-Color strings are case-insensitive.
-</para>
-<para>
-<!-- .LP -->
-Color strings are used in the following functions:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-<function>XAllocNamedColor</function>
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XcmsAllocNamedColor</function>
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XLookupColor</function>
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XcmsLookupColor</function>
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XParseColor</function>
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XStoreNamedColor</function>
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Xlib supports the use of abstract color names, for example, red or blue.
-A value for this abstract name is obtained by searching one or more color
-name databases.
-Xlib first searches zero or more client-side databases;
-the number, location, and content of these databases is
-implementation-dependent and might depend on the current locale.
-If the name is not found, Xlib then looks for the color in the
-X server's database.
-If the color name is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-A numerical color specification
-consists of a color space name and a set of values in the following syntax:
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<literallayout class="monospaced">
-<emphasis remap='I'>&lt;color_space_name&gt;</emphasis>:<emphasis remap='I'>&lt;value&gt;/.../&lt;value&gt;</emphasis>
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The following are examples of valid color strings.
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-"CIEXYZ:0.3227/0.28133/0.2493"
-"RGBi:1.0/0.0/0.0"
-"rgb:00/ff/00"
-"CIELuv:50.0/0.0/0.0"
-</literallayout>
-The syntax and semantics of numerical specifications are given
-for each standard color space in the following sections.
-</para>
-<sect2 id="RGB_Device_String_Specification">
-<title><acronym>RGB</acronym> Device String Specification</title>
-<!-- .XS -->
-<!-- (SN <acronym>RGB</acronym> Device String Specification -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-An <acronym>RGB</acronym> Device specification is identified by
-the prefix ``rgb:'' and conforms to the following syntax:
-</para>
-<para>
-<!-- .LP -->
-<!-- .\" Start marker code here -->
-<literallayout class="monospaced">
-rgb:<emphasis remap='I'>&lt;red&gt;/&lt;green&gt;/&lt;blue&gt;</emphasis>
-
- <emphasis remap='I'>&lt;red&gt;</emphasis>, <emphasis remap='I'>&lt;green&gt;</emphasis>, <emphasis remap='I'>&lt;blue&gt;</emphasis> := <emphasis remap='I'>h</emphasis> | <emphasis remap='I'>hh</emphasis> | <emphasis remap='I'>hhh</emphasis> | <emphasis remap='I'>hhhh</emphasis>
- <emphasis remap='I'>h</emphasis> := single hexadecimal digits (case insignificant)
-</literallayout>
-<!-- .\" End marker code here -->
-</para>
-<para>
-<!-- .LP -->
-Note that <emphasis remap='I'>h</emphasis> indicates the value scaled in 4 bits,
-<emphasis remap='I'>hh</emphasis> the value scaled in 8 bits,
-<emphasis remap='I'>hhh</emphasis> the value scaled in 12 bits,
-and <emphasis remap='I'>hhhh</emphasis> the value scaled in 16 bits, respectively.
-</para>
-<para>
-<!-- .LP -->
-Typical examples are the strings ``rgb:ea/75/52'' and ``rgb:ccc/320/320'',
-but mixed numbers of hexadecimal digit strings
-(``rgb:ff/a5/0'' and ``rgb:ccc/32/0'')
-are also allowed.
-</para>
-<para>
-<!-- .LP -->
-For backward compatibility, an older syntax for <acronym>RGB</acronym> Device is
-supported, but its continued use is not encouraged.
-The syntax is an initial sharp sign character followed by
-a numeric specification, in one of the following formats:
-</para>
-<para>
-<!-- .LP -->
-<!-- .\" Start marker code here -->
-<literallayout class="monospaced">
-<!-- .TA 2i -->
-<!-- .ta 2i -->
-#RGB (4 bits each)
-#RRGGBB (8 bits each)
-#RRRGGGBBB (12 bits each)
-#RRRRGGGGBBBB (16 bits each)
-</literallayout>
-<!-- .\" End marker code here -->
-</para>
-<para>
-<!-- .LP -->
-The R, G, and B represent single hexadecimal digits.
-When fewer than 16 bits each are specified,
-they represent the most significant bits of the value
-(unlike the ``rgb:'' syntax, in which values are scaled).
-For example, the string ``#3a7'' is the same as ``#3000a0007000''.
-</para>
-</sect2>
-<sect2 id="RGB_Intensity_String_Specification">
-<title><acronym>RGB</acronym> Intensity String Specification</title>
-<!-- .XS -->
-<!-- (SN RGB Intensity String Specification -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-An <acronym>RGB</acronym> intensity specification is identified
-by the prefix ``rgbi:'' and conforms to the following syntax:
-</para>
-<para>
-<!-- .LP -->
-<!-- .\" Start marker code here -->
-<literallayout class="monospaced">
-rgbi:<emphasis remap='I'>&lt;red&gt;/&lt;green&gt;/&lt;blue&gt;</emphasis>
-</literallayout>
-<!-- .\" End marker code here -->
-</para>
-<para>
-<!-- .LP -->
-Note that red, green, and blue are floating-point values
-between 0.0 and 1.0, inclusive.
-The input format for these values is an optional sign,
-a string of numbers possibly containing a decimal point,
-and an optional exponent field containing an E or e
-followed by a possibly signed integer string.
-</para>
-</sect2>
-<sect2 id="Device_Independent_String_Specifications">
-<title>Device-Independent String Specifications</title>
-<!-- .XS -->
-<!-- (SN Device-Independent String Specifications -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The standard device-independent string specifications have
-the following syntax:
-</para>
-<para>
-<!-- .LP -->
-<!-- .\" Start marker code here -->
-<literallayout class="monospaced">
-CIEXYZ:<emphasis remap='I'>&lt;X&gt;/&lt;Y&gt;/&lt;Z&gt;</emphasis>
-CIEuvY:<emphasis remap='I'>&lt;u&gt;/&lt;v&gt;/&lt;Y&gt;</emphasis>
-CIExyY:<emphasis remap='I'>&lt;x&gt;/&lt;y&gt;/&lt;Y&gt;</emphasis>
-CIELab:<emphasis remap='I'>&lt;L&gt;/&lt;a&gt;/&lt;b&gt;</emphasis>
-CIELuv:<emphasis remap='I'>&lt;L&gt;/&lt;u&gt;/&lt;v&gt;</emphasis>
-TekHVC:<emphasis remap='I'>&lt;H&gt;/&lt;V&gt;/&lt;C&gt;</emphasis>
-</literallayout>
-<!-- .\" End marker code here -->
-</para>
-<para>
-<!-- .LP -->
-All of the values (C, H, V, X, Y, Z, a, b, u, v, y, x) are
-floating-point values.
-The syntax for these values is an optional plus or minus sign,
-a string of digits possibly containing a decimal point,
-and an optional exponent field consisting of an ``E'' or ``e''
-followed by an optional plus or minus followed by a string of digits.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Color_Conversion_Contexts_and_Gamut_Mapping">
-<title>Color Conversion Contexts and Gamut Mapping</title>
-<!-- .XS -->
-<!-- (SN Color Conversion Contexts and Gamut Mapping -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-When Xlib converts device-independent color specifications
-into device-dependent specifications and vice versa,
-it uses knowledge about the color limitations of the screen hardware.
-This information, typically called the device profile,
-<indexterm><primary>Device profile</primary></indexterm>
-is available in a Color Conversion Context (CCC).
-<indexterm><primary>Color Conversion Context</primary></indexterm>
-<indexterm><primary>CCC</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-Because a specified color may be outside the color gamut of the target screen
-and the white point associated with the color specification may differ
-from the white point inherent to the screen,
-Xlib applies gamut mapping when it encounters certain conditions:
-<indexterm><primary>White point</primary></indexterm>
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Gamut compression occurs when conversion of device-independent
-color specifications to device-dependent color specifications
-results in a color out of the target screen's gamut.
- </para>
- </listitem>
- <listitem>
- <para>
-White adjustment occurs when the inherent white point of the screen
-differs from the white point assumed by the client.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Gamut handling methods are stored as callbacks in the CCC,
-which in turn are used by the color space conversion routines.
-Client data is also stored in the CCC for each callback.
-The CCC also contains the white point the client assumes to be
-associated with color specifications (that is, the Client White Point).
-<indexterm><primary>Client White Point</primary></indexterm>
-<indexterm><primary>Gamut compression</primary></indexterm>
-<indexterm><primary>Gamut handling</primary></indexterm>
-<indexterm><primary>White point adjustment</primary></indexterm>
-The client can specify the gamut handling callbacks and client data
-as well as the Client White Point.
-Xlib does not preclude the X client from performing other
-forms of gamut handling (for example, gamut expansion);
-however, Xlib does not provide direct support for gamut handling
-other than white adjustment and gamut compression.
-</para>
-<para>
-<!-- .LP -->
-Associated with each colormap is an initial CCC transparently generated by
-Xlib.
-<indexterm><primary>Color Conversion Context</primary><secondary>creation</secondary></indexterm>
-Therefore,
-when you specify a colormap as an argument to an Xlib function,
-you are indirectly specifying a CCC.
-<indexterm><primary>CCC</primary><secondary>of colormap</secondary></indexterm>
-<indexterm><primary>Color Conversion Context</primary><secondary>of colormap</secondary></indexterm>
-There is a default CCC associated with each screen.
-Newly created CCCs inherit attributes from the default CCC,
-so the default CCC attributes can be modified to affect new CCCs.
-<indexterm><primary>CCC</primary><secondary>default</secondary></indexterm>
-<indexterm><primary>Color Conversion Context</primary><secondary>default</secondary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-Xcms functions in which gamut mapping can occur return
-<type>Status</type>
-and have specific status values defined for them,
-as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-<symbol>XcmsFailure</symbol>
-indicates that the function failed.
- </para>
- </listitem>
- <listitem>
- <para>
-<symbol>XcmsSuccess</symbol>
-indicates that the function succeeded.
-In addition,
-if the function performed any color conversion,
-the colors did not need to be compressed.
- </para>
- </listitem>
- <listitem>
- <para>
-<symbol>XcmsSuccessWithCompression</symbol>
-indicates the function performed color conversion
-and at least one of the colors needed to be compressed.
-The gamut compression method is determined by the gamut compression
-procedure in the CCC that is specified directly as a function argument
-or in the CCC indirectly specified by means of the colormap argument.
- </para>
- </listitem>
-</itemizedlist>
-</sect1>
-<sect1 id="Creating_Copying_and_Destroying_Colormaps">
-<title>Creating, Copying, and Destroying Colormaps</title>
-<!-- .XS -->
-<!-- (SN Creating, Copying, and Destroying Colormaps -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To create a colormap for a screen, use
-<function>XCreateColormap</function>.</para>
-<indexterm significance="preferred"><primary>XCreateColormap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Colormap <function>XCreateColormap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Visual<parameter> *visual</parameter></paramdef>
- <paramdef>int<parameter> alloc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Wi on whose screen you want to create a colormap -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window (Wi.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>visual</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a visual type supported on the screen.
-If the visual type is not one supported by the screen,
-a
-<errorname>BadMatch</errorname>
-error results.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>alloc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap entries to be allocated.
-You can pass
-<symbol>AllocNone</symbol>
-or
-<symbol>AllocAll</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreateColormap</function>
-function creates a colormap of the specified visual type for the screen
-on which the specified window resides and returns the colormap ID
-associated with it.
-Note that the specified window is only used to determine the screen.
-</para>
-<para>
-<!-- .LP -->
-The initial values of the colormap entries are undefined for the
-visual classes
-<symbol>GrayScale</symbol>,
-<symbol>PseudoColor</symbol>,
-and
-<symbol>DirectColor</symbol>.
-For
-<symbol>StaticGray</symbol>,
-<symbol>StaticColor</symbol>,
-and
-<symbol>TrueColor</symbol>,
-the entries have defined values,
-but those values are specific to the visual and are not defined by X.
-For
-<symbol>StaticGray</symbol>,
-<symbol>StaticColor</symbol>,
-and
-<symbol>TrueColor</symbol>,
-alloc must be
-<symbol>AllocNone</symbol>,
-or a
-<errorname>BadMatch</errorname>
-error results.
-For the other visual classes,
-if alloc is
-<symbol>AllocNone</symbol>,
-the colormap initially has no allocated entries,
-and clients can allocate them.
-For information about the visual types,
-see section 3.1.
-</para>
-<para>
-<!-- .LP -->
-If alloc is
-<symbol>AllocAll</symbol>,
-the entire colormap is allocated writable.
-The initial values of all allocated entries are undefined.
-For
-<symbol>GrayScale</symbol>
-and
-<symbol>PseudoColor</symbol>,
-the effect is as if an
-<function>XAllocColorCells</function>
-call returned all pixel values from zero to N - 1,
-where N is the colormap entries value in the specified visual.
-For
-<symbol>DirectColor</symbol>,
-the effect is as if an
-<function>XAllocColorPlanes</function>
-call returned a pixel value of zero and red_mask, green_mask,
-and blue_mask values containing the same bits as the corresponding
-masks in the specified visual.
-However, in all cases,
-none of these entries can be freed by using
-<function>XFreeColors</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreateColormap</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadMatch</errorname>,
-<errorname>BadValue</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create a new colormap when the allocation out of a previously
-shared colormap has failed because of resource exhaustion, use
-<function>XCopyColormapAndFree</function>.
-<indexterm significance="preferred"><primary>XCopyColormapAndFree</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Colormap <function>XCopyColormapAndFree</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCopyColormapAndFree</function>
-function creates a colormap of the same visual type and for the same screen
-as the specified colormap and returns the new colormap ID.
-It also moves all of the client's existing allocation from the specified
-colormap to the new colormap with their color values intact
-and their read-only or writable characteristics intact and frees those entries
-in the specified colormap.
-Color values in other entries in the new colormap are undefined.
-If the specified colormap was created by the client with alloc set to
-<symbol>AllocAll</symbol>,
-the new colormap is also created with
-<symbol>AllocAll</symbol>,
-all color values for all entries are copied from the specified colormap,
-and then all entries in the specified colormap are freed.
-If the specified colormap was not created by the client with
-<symbol>AllocAll</symbol>,
-the allocations to be moved are all those pixels and planes
-that have been allocated by the client using
-<function>XAllocColor</function>,
-<function>XAllocNamedColor</function>,
-<function>XAllocColorCells</function>,
-or
-<function>XAllocColorPlanes</function>
-and that have not been freed since they were allocated.
-</para>
-<para>
-<!-- .LP -->
-<function>XCopyColormapAndFree</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadColor</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To destroy a colormap, use
-<function>XFreeColormap</function>.
-<indexterm significance="preferred"><primary>XFreeColormap</primary></indexterm>
-</para>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFreeColormap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Cm that you want to destroy -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap (Cm.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreeColormap</function>
-function deletes the association between the colormap resource ID
-and the colormap and frees the colormap storage.
-However, this function has no effect on the default colormap for a screen.
-If the specified colormap is an installed map for a screen,
-it is uninstalled (see
-<function>XUninstallColormap</function>).
-If the specified colormap is defined as the colormap for a window (by
-<function>XCreateWindow</function>,
-<function>XSetWindowColormap</function>,
-or
-<function>XChangeWindowAttributes</function>),
-<function>XFreeColormap</function>
-changes the colormap associated with the window to
-<symbol>None</symbol>
-and generates a
-<symbol>ColormapNotify</symbol>
-event.
-X does not define the colors displayed for a window with a colormap of
-<symbol>None</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<function>XFreeColormap</function>
-can generate a
-<errorname>BadColor</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Mapping_Color_Names_to_Values">
-<title>Mapping Color Names to Values</title>
-<!-- .XS -->
-<!-- (SN Mapping Color Names to Values -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To map a color name to an <acronym>RGB</acronym> value, use
-<function>XLookupColor</function>.
-<indexterm><primary>Color</primary><secondary>naming</secondary></indexterm>
-<indexterm significance="preferred"><primary>XLookupColor</primary></indexterm>
-<!-- .sM -->
-</para>
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XLookupColor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>char<parameter> *color_name</parameter></paramdef>
- <paramdef>XColor*exact_def_return,<parameter> *screen_def_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color name string (for example, red) whose color
-definition structure you want returned.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>exact_def_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the exact <acronym>RGB</acronym> values.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen_def_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the closest <acronym>RGB</acronym> values provided by the hardware.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XLookupColor</function>
-function looks up the string name of a color with respect to the screen
-associated with the specified colormap.
-It returns both the exact color values and
-the closest values provided by the screen
-with respect to the visual type of the specified colormap.
-If the color name is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-Use of uppercase or lowercase does not matter.
-<function>XLookupColor</function>
-returns nonzero if the name is resolved;
-otherwise, it returns zero.
-</para>
-<para>
-<!-- .LP -->
-<function>XLookupColor</function>
-can generate a
-<errorname>BadColor</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To map a color name to the exact <acronym>RGB</acronym> value, use
-<function>XParseColor</function>.
-</para>
-<indexterm><primary>Color</primary><secondary>naming</secondary></indexterm>
-<indexterm significance="preferred"><primary>XParseColor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XParseColor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>char<parameter> *spec</parameter></paramdef>
- <paramdef>XColor<parameter> *exact_def_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>spec</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color name string;
-case is ignored.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>exact_def_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the exact color value for later use and sets the
-<symbol>DoRed</symbol>,
-<symbol>DoGreen</symbol>,
-and
-<symbol>DoBlue</symbol>
-flags.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XParseColor</function>
-function looks up the string name of a color with respect to the screen
-associated with the specified colormap.
-It returns the exact color value.
-If the color name is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-Use of uppercase or lowercase does not matter.
-<function>XParseColor</function>
-returns nonzero if the name is resolved;
-otherwise, it returns zero.
-</para>
-<para>
-<!-- .LP -->
-<function>XParseColor</function>
-can generate a
-<errorname>BadColor</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To map a color name to a value in an arbitrary color space, use
-<function>XcmsLookupColor</function>.
-</para>
-<indexterm><primary>Color</primary><secondary>naming</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsLookupColor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsLookupColor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>char<parameter> *color_string</parameter></paramdef>
- <paramdef>XcmsColor*color_exact_return,<parameter> *color_screen_return</parameter></paramdef>
- <paramdef>XcmsColorFormat<parameter> result_format</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
-<!-- .ds St -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color string(St.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_exact_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the color specification parsed from the color string
-or parsed from the corresponding string found in a color-name database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_screen_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the color that can be reproduced on the screen.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>result_format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color format for the returned color
-specifications (color_screen_return and color_exact_return arguments).
-If the format is
-<symbol>XcmsUndefinedFormat</symbol>
-and the color string contains a
-numerical color specification,
-the specification is returned in the format used in that numerical
-color specification.
-If the format is
-<symbol>XcmsUndefinedFormat</symbol>
-and the color string contains a color name,
-the specification is returned in the format used
-to store the color in the database.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsLookupColor</function>
-function looks up the string name of a color with respect to the screen
-associated with the specified colormap.
-It returns both the exact color values and
-the closest values provided by the screen
-with respect to the visual type of the specified colormap.
-The values are returned in the format specified by result_format.
-If the color name is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-Use of uppercase or lowercase does not matter.
-<function>XcmsLookupColor</function>
-returns
-<symbol>XcmsSuccess</symbol>
-or
-<symbol>XcmsSuccessWithCompression</symbol>
-if the name is resolved; otherwise, it returns
-<symbol>XcmsFailure</symbol>.
-If
-<symbol>XcmsSuccessWithCompression</symbol>
-is returned, the color specification returned in
-color_screen_return is the result of gamut compression.
-</para>
-</sect1>
-
-<sect1 id="Allocating_and_Freeing_Color_Cells">
-<title>Allocating and Freeing Color Cells</title>
-<!-- .XS -->
-<!-- (SN Allocating and Freeing Color Cells -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-There are two ways of allocating color cells:
-explicitly as read-only entries, one pixel value at a time,
-or read/write,
-where you can allocate a number of color cells and planes simultaneously.
-<indexterm><primary>Read-only colormap cells</primary></indexterm>
-A read-only cell has its <acronym>RGB</acronym> value set by the server.
-<indexterm><primary>Read/write colormap cells</primary></indexterm>
-Read/write cells do not have defined colors initially;
-functions described in the next section must be used to store values into them.
-Although it is possible for any client to store values into a read/write
-cell allocated by another client,
-read/write cells normally should be considered private to the client
-that allocated them.
-</para>
-<para>
-<!-- .LP -->
-Read-only colormap cells are shared among clients.
-The server counts each allocation and freeing of the cell by clients.
-When the last client frees a shared cell, the cell is finally deallocated.
-If a single client allocates the same read-only cell multiple
-times, the server counts each such allocation, not just the first one.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To allocate a read-only color cell with an <acronym>RGB</acronym> value, use
-<function>XAllocColor</function>.
-</para>
-<indexterm><primary>Allocation</primary><secondary>read-only colormap cells</secondary></indexterm>
-<indexterm><primary>Read-only colormap cells</primary><secondary>allocating</secondary></indexterm>
-<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
-<indexterm significance="preferred"><primary>XAllocColor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XAllocColor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>XColor<parameter> *screen_in_out</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies and returns the values actually used in the colormap.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAllocColor</function>
-function allocates a read-only colormap entry corresponding to the closest
-<acronym>RGB</acronym> value supported by the hardware.
-<function>XAllocColor</function>
-returns the pixel value of the color closest to the specified
-<acronym>RGB</acronym> elements supported by the hardware
-and returns the <acronym>RGB</acronym> value actually used.
-The corresponding colormap cell is read-only.
-In addition,
-<function>XAllocColor</function>
-returns nonzero if it succeeded or zero if it failed.
-<indexterm><primary>Color map</primary></indexterm>
-<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
-<indexterm><primary>Allocation</primary><secondary>colormap</secondary></indexterm>
-<indexterm><primary>read-only colormap cells</primary></indexterm>
-Multiple clients that request the same effective <acronym>RGB</acronym> value can be assigned
-the same read-only entry, thus allowing entries to be shared.
-When the last client deallocates a shared cell, it is deallocated.
-<function>XAllocColor</function>
-does not use or affect the flags in the
-<structname>XColor</structname>
-structure.
-</para>
-<para>
-<!-- .LP -->
-<function>XAllocColor</function>
-can generate a
-<errorname>BadColor</errorname>
-error.
-<!-- .EQ -->
-delim %%
-<!-- .EN -->
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To allocate a read-only color cell with a color in arbitrary format, use
-<function>XcmsAllocColor</function>.
-</para>
-<indexterm><primary>Allocation</primary><secondary>read-only colormap cells</secondary></indexterm>
-<indexterm><primary>Read-only colormap cells</primary><secondary>allocating</secondary></indexterm>
-<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsAllocColor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsAllocColor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_in_out</parameter></paramdef>
- <paramdef>XcmsColorFormat<parameter> result_format</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color to allocate and returns the pixel and color
-that is actually used in the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>result_format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color format for the returned color specification.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsAllocColor</function>
-function is similar to
-<function>XAllocColor</function>
-except the color can be specified in any format.
-The
-<function>XcmsAllocColor</function>
-function ultimately calls
-<function>XAllocColor</function>
-to allocate a read-only color cell (colormap entry) with the specified color.
-<function>XcmsAllocColor</function>
-first converts the color specified
-to an <acronym>RGB</acronym> value and then passes this to
-<function>XAllocColor</function>.
-<function>XcmsAllocColor</function>
-returns the pixel value of the color cell and the color specification
-actually allocated.
-This returned color specification is the result of converting the <acronym>RGB</acronym> value
-returned by
-<function>XAllocColor</function>
-into the format specified with the result_format argument.
-If there is no interest in a returned color specification,
-unnecessary computation can be bypassed if result_format is set to
-<symbol>XcmsRGBFormat</symbol>.
-The corresponding colormap cell is read-only.
-If this routine returns
-<symbol>XcmsFailure</symbol>,
-the color_in_out color specification is left unchanged.
-</para>
-<para>
-<!-- .LP -->
-<function>XcmsAllocColor</function>
-can generate a
-<errorname>BadColor</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To allocate a read-only color cell using a color name and return the closest
-color supported by the hardware in <acronym>RGB</acronym> format, use
-<function>XAllocNamedColor</function>.
-</para>
-<indexterm><primary>Allocation</primary><secondary>read-only colormap cells</secondary></indexterm>
-<indexterm><primary>Read-only colormap cells</primary><secondary>allocating</secondary></indexterm>
-<indexterm><primary>Color</primary><secondary>naming</secondary></indexterm>
-<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
-<indexterm significance="preferred"><primary>XAllocNamedColor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XAllocNamedColor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>char<parameter> *color_name</parameter></paramdef>
- <paramdef>XColor*screen_def_return,<parameter> *exact_def_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color name string (for example, red) whose color
-definition structure you want returned.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen_def_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the closest <acronym>RGB</acronym> values provided by the hardware.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>exact_def_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the exact <acronym>RGB</acronym> values.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAllocNamedColor</function>
-function looks up the named color with respect to the screen that is
-associated with the specified colormap.
-It returns both the exact database definition and
-the closest color supported by the screen.
-The allocated color cell is read-only.
-The pixel value is returned in screen_def_return.
-If the color name is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-Use of uppercase or lowercase does not matter.
-If screen_def_return and exact_def_return
-point to the same structure, the pixel field will be set correctly,
-but the color values are undefined.
-<function>XAllocNamedColor</function>
-returns nonzero if a cell is allocated;
-otherwise, it returns zero.
-</para>
-<para>
-<!-- .LP -->
-<function>XAllocNamedColor</function>
-can generate a
-<errorname>BadColor</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To allocate a read-only color cell using a color name and return the closest
-color supported by the hardware in an arbitrary format, use
-<function>XcmsAllocNamedColor</function>.
-</para>
-<indexterm><primary>Allocation</primary><secondary>read-only colormap cells</secondary></indexterm>
-<indexterm><primary>Read-only colormap cells</primary><secondary>allocating</secondary></indexterm>
-<indexterm><primary>Color</primary><secondary>naming</secondary></indexterm>
-<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsAllocNamedColor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsAllocNamedColor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>char<parameter> *color_string</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_screen_return</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_exact_return</parameter></paramdef>
- <paramdef>XcmsColorFormat<parameter> result_format</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
-<!-- .ds St \ whose color definition structure is to be returned -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color string(St.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_screen_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the pixel value of the color cell and color specification
-that actually is stored for that cell.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_exact_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the color specification parsed from the color string
-or parsed from the corresponding string found in a color-name database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>result_format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color format for the returned color
-specifications (color_screen_return and color_exact_return arguments).
-If the format is
-<symbol>XcmsUndefinedFormat</symbol>
-and the color string contains a
-numerical color specification,
-the specification is returned in the format used in that numerical
-color specification.
-If the format is
-<symbol>XcmsUndefinedFormat</symbol>
-and the color string contains a color name,
-the specification is returned in the format used
-to store the color in the database.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsAllocNamedColor</function>
-function is similar to
-<function>XAllocNamedColor</function>
-except that the color returned can be in any format specified.
-This function
-ultimately calls
-<function>XAllocColor</function>
-to allocate a read-only color cell with
-the color specified by a color string.
-The color string is parsed into an
-<structname>XcmsColor</structname>
-structure (see
-<function>XcmsLookupColor</function>),
-converted
-to an <acronym>RGB</acronym> value, and finally passed to
-<function>XAllocColor</function>.
-If the color name is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-Use of uppercase or lowercase does not matter.
-</para>
-<para>
-<!-- .LP -->
-This function returns both the color specification as a result
-of parsing (exact specification) and the actual color specification
-stored (screen specification).
-This screen specification is the result of converting the <acronym>RGB</acronym> value
-returned by
-<function>XAllocColor</function>
-into the format specified in result_format.
-If there is no interest in a returned color specification,
-unnecessary computation can be bypassed if result_format is set to
-<symbol>XcmsRGBFormat</symbol>.
-If color_screen_return and color_exact_return
-point to the same structure, the pixel field will be set correctly,
-but the color values are undefined.
-</para>
-<para>
-<!-- .LP -->
-<function>XcmsAllocNamedColor</function>
-can generate a
-<errorname>BadColor</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To allocate read/write color cell and color plane combinations for a
-<symbol>PseudoColor</symbol>
-model, use
-<function>XAllocColorCells</function>.
-</para>
-<indexterm><primary>Read/write colormap cells</primary><secondary>allocating</secondary></indexterm>
-<indexterm><primary>Allocation</primary><secondary>read/write colormap cells</secondary></indexterm>
-<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
-<indexterm significance="preferred"><primary>XAllocColorCells</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XAllocColorCells</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>Bool<parameter> contig</parameter></paramdef>
- <paramdef>unsignedlong<parameter> plane_masks_return[]</parameter></paramdef>
- <paramdef>unsignedint<parameter> nplanes</parameter></paramdef>
- <paramdef>unsignedlong<parameter> pixels_return[]</parameter></paramdef>
- <paramdef>unsignedint<parameter> npixels</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>contig</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value that indicates whether the planes must be contiguous.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>plane_mask_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns an array of plane masks.
-<!-- .\" *** JIM: NEED MORE INFO FOR THIS. *** -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nplanes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of plane masks that are to be returned in the plane masks
-array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pixels_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns an array of pixel values.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>npixels</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of pixel values that are to be returned in the
-pixels_return array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAllocColorCells</function>
-function allocates read/write color cells.
-The number of colors must be positive and the number of planes nonnegative,
-or a
-<errorname>BadValue</errorname>
-error results.
-If ncolors and nplanes are requested,
-then ncolors pixels
-and nplane plane masks are returned.
-No mask will have any bits set to 1 in common with
-any other mask or with any of the pixels.
-By ORing together each pixel with zero or more masks,
-ncolors &times; 2<superscript><emphasis>nplanes</emphasis></superscript>
-distinct pixels can be produced.
-All of these are
-allocated writable by the request.
-For
-<symbol>GrayScale</symbol>
-or
-<symbol>PseudoColor</symbol>,
-each mask has exactly one bit set to 1.
-For
-<symbol>DirectColor</symbol>,
-each has exactly three bits set to 1.
-If contig is
-<symbol>True</symbol>
-and if all masks are ORed
-together, a single contiguous set of bits set to 1 will be formed for
-<symbol>GrayScale</symbol>
-or
-<symbol>PseudoColor</symbol>
-and three contiguous sets of bits set to 1 (one within each
-pixel subfield) for
-<symbol>DirectColor</symbol>.
-The <acronym>RGB</acronym> values of the allocated
-entries are undefined.
-<function>XAllocColorCells</function>
-returns nonzero if it succeeded or zero if it failed.
-</para>
-<para>
-<!-- .LP -->
-<function>XAllocColorCells</function>
-can generate
-<errorname>BadColor</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To allocate read/write color resources for a
-<symbol>DirectColor</symbol>
-model, use
-<function>XAllocColorPlanes</function>.
-</para>
-<indexterm><primary>Read/write colormap planes</primary><secondary>allocating</secondary></indexterm>
-<indexterm><primary>Allocation</primary><secondary>read/write colormap planes</secondary></indexterm>
-<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
-<indexterm significance="preferred"><primary>XAllocColorPlanes</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XAllocColorPlanes</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>Bool<parameter> contig</parameter></paramdef>
- <paramdef>unsignedlong<parameter> pixels_return[]</parameter></paramdef>
- <paramdef>int<parameter> ncolors</parameter></paramdef>
- <paramdef>intnreds,ngreens,<parameter> nblues</parameter></paramdef>
- <paramdef>unsignedlong*rmask_return,*gmask_return,<parameter> *bmask_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>contig</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value that indicates whether the planes must be contiguous.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pixels_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns an array of pixel values.
-<function>XAllocColorPlanes</function>
-returns the pixel values in this array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ncolors</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of pixel values that are to be returned in the
-pixels_return array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nreds</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ngreens</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nblues</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
-Specify the number of red, green, and blue planes.
-The value you pass must be nonnegative.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>rmask_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gmask_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bmask_return</emphasis>
- </term>
- <listitem>
- <para>
-Return bit masks for the red, green, and blue planes.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The specified ncolors must be positive;
-and nreds, ngreens, and nblues must be nonnegative,
-or a
-<errorname>BadValue</errorname>
-error results.
-If ncolors colors, nreds reds, ngreens greens, and nblues blues are requested,
-ncolors pixels are returned; and the masks have nreds, ngreens, and
-nblues bits set to 1, respectively.
-If contig is
-<symbol>True</symbol>,
-each mask will have
-a contiguous set of bits set to 1.
-No mask will have any bits set to 1 in common with
-any other mask or with any of the pixels.
-For
-<symbol>DirectColor</symbol>,
-each mask
-will lie within the corresponding pixel subfield.
-By ORing together
-subsets of masks with each pixel value,
-ncolors &times; 2<superscript><emphasis>(nreds+ngreens+nblues)</emphasis></superscript>
-distinct pixel values can be produced.
-All of these are allocated by the request.
-However, in the
-colormap, there are only
-ncolors &times; 2<superscript><emphasis>nreds</emphasis></superscript>
-independent red entries,
-ncolors &times; 2<superscript><emphasis>ngreens</emphasis></superscript>
-independent green entries, and
-ncolors &times; 2<superscript><emphasis>nblues</emphasis></superscript>
-independent blue entries.
-This is true even for
-<symbol>PseudoColor</symbol>.
-When the colormap entry of a pixel
-value is changed (using
-<function>XStoreColors</function>,
-<function>XStoreColor</function>,
-or
-<function>XStoreNamedColor</function>),
-the pixel is decomposed according to the masks,
-and the corresponding independent entries are updated.
-<function>XAllocColorPlanes</function>
-returns nonzero if it succeeded or zero if it failed.
-</para>
-<para>
-<!-- .LP -->
-<function>XAllocColorPlanes</function>
-can generate
-<errorname>BadColor</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-<indexterm><primary>Freeing</primary><secondary>colors</secondary></indexterm>
-To free colormap cells, use
-<function>XFreeColors</function>.
-<indexterm significance="preferred"><primary>XFreeColors</primary></indexterm>
-<indexterm><primary>Color</primary><secondary>deallocation</secondary></indexterm>
-<!-- .sM -->
-</para>
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFreeColors</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>unsignedlong<parameter> pixels[]</parameter></paramdef>
- <paramdef>int<parameter> npixels</parameter></paramdef>
- <paramdef>unsignedlong<parameter> planes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
-<!-- .ds Pi that map to the cells in the specified colormap -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pixels</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of pixel values (Pi.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>npixels</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of pixels.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>planes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the planes you want to free.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreeColors</function>
-function frees the cells represented by pixels whose values are in the
-pixels array.
-The planes argument should not have any bits set to 1 in common with any of the
-pixels.
-The set of all pixels is produced by ORing together subsets of
-the planes argument with the pixels.
-The request frees all of these pixels that
-were allocated by the client (using
-<indexterm><primary>XAllocColor</primary></indexterm>
-<indexterm><primary>XAllocNamedColor</primary></indexterm>
-<indexterm><primary>XAllocColorCells</primary></indexterm>
-<indexterm><primary>XAllocColorPlanes</primary></indexterm>
-<function>XAllocColor</function>,
-<function>XAllocNamedColor</function>,
-<function>XAllocColorCells</function>,
-and
-<function>XAllocColorPlanes</function>).
-Note that freeing an
-individual pixel obtained from
-<function>XAllocColorPlanes</function>
-may not actually allow
-it to be reused until all of its related pixels are also freed.
-Similarly,
-a read-only entry is not actually freed until it has been freed by all clients,
-and if a client allocates the same read-only entry multiple times,
-it must free the entry that many times before the entry is actually freed.
-</para>
-<para>
-<!-- .LP -->
-All specified pixels that are allocated by the client in the colormap are
-freed, even if one or more pixels produce an error.
-If a specified pixel is not a valid index into the colormap, a
-<errorname>BadValue</errorname>
-error results.
-If a specified pixel is not allocated by the
-client (that is, is unallocated or is only allocated by another client)
-or if the colormap was created with all entries writable (by passing
-<symbol>AllocAll</symbol>
-to
-<function>XCreateColormap</function>),
-a
-<errorname>BadAccess</errorname>
-error results.
-If more than one pixel is in error,
-the one that gets reported is arbitrary.
-</para>
-<para>
-<!-- .LP -->
-<function>XFreeColors</function>
-can generate
-<errorname>BadAccess</errorname>,
-<errorname>BadColor</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-</sect1>
-<sect1 id="Modifying_and_Querying_Colormap_Cells">
-<title>Modifying and Querying Colormap Cells</title>
-<!-- .XS -->
-<!-- (SN Modifying and Querying Colormap Cells -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To store an <acronym>RGB</acronym> value in a single colormap cell, use
-<function>XStoreColor</function>.
-</para>
-<indexterm><primary>Color</primary><secondary>storing</secondary></indexterm>
-<indexterm significance="preferred"><primary>XStoreColor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XStoreColor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>XColor<parameter> *color</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the pixel and <acronym>RGB</acronym> values.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XStoreColor</function>
-function changes the colormap entry of the pixel value specified in the
-pixel member of the
-<structname>XColor</structname>
-structure.
-You specified this value in the
-pixel member of the
-<structname>XColor</structname>
-structure.
-This pixel value must be a read/write cell and a valid index into the colormap.
-If a specified pixel is not a valid index into the colormap,
-a
-<errorname>BadValue</errorname>
-error results.
-<function>XStoreColor</function>
-also changes the red, green, and/or blue color components.
-You specify which color components are to be changed by setting
-<symbol>DoRed</symbol>,
-<symbol>DoGreen</symbol>,
-and/or
-<symbol>DoBlue</symbol>
-in the flags member of the
-<structname>XColor</structname>
-structure.
-If the colormap is an installed map for its screen,
-the changes are visible immediately.
-</para>
-<para>
-<!-- .LP -->
-<function>XStoreColor</function>
-can generate
-<errorname>BadAccess</errorname>,
-<errorname>BadColor</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To store multiple <acronym>RGB</acronym> values in multiple colormap cells, use
-<function>XStoreColors</function>.
-</para>
-<indexterm><primary>Color</primary><secondary>storing</secondary></indexterm>
-<indexterm significance="preferred"><primary>XStoreColors</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XStoreColors</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>XColor<parameter> color[]</parameter></paramdef>
- <paramdef>int<parameter> ncolors</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of color definition structures to be stored.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ncolors</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .\"Specifies the number of color definition structures. -->
-Specifies the number of
-<structname>XColor</structname>
-structures in the color definition array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XStoreColors</function>
-function changes the colormap entries of the pixel values
-specified in the pixel members of the
-<structname>XColor</structname>
-structures.
-You specify which color components are to be changed by setting
-<symbol>DoRed</symbol>,
-<symbol>DoGreen</symbol>,
-and/or
-<symbol>DoBlue</symbol>
-in the flags member of the
-<structname>XColor</structname>
-structures.
-If the colormap is an installed map for its screen, the
-changes are visible immediately.
-<function>XStoreColors</function>
-changes the specified pixels if they are allocated writable in the colormap
-by any client, even if one or more pixels generates an error.
-If a specified pixel is not a valid index into the colormap, a
-<errorname>BadValue</errorname>
-error results.
-If a specified pixel either is unallocated or is allocated read-only, a
-<errorname>BadAccess</errorname>
-error results.
-If more than one pixel is in error,
-the one that gets reported is arbitrary.
-</para>
-<para>
-<!-- .LP -->
-<function>XStoreColors</function>
-can generate
-<errorname>BadAccess</errorname>,
-<errorname>BadColor</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To store a color of arbitrary format in a single colormap cell, use
-<function>XcmsStoreColor</function>.
-</para>
-<indexterm><primary>Color</primary><secondary>storing</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsStoreColor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsStoreColor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color cell and the color to store.
-Values specified in this
-<structname>XcmsColor</structname>
-structure remain unchanged on return.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsStoreColor</function>
-function converts the color specified in the
-<structname>XcmsColor</structname>
-structure into <acronym>RGB</acronym> values.
-It then uses this <acronym>RGB</acronym> specification in an
-<structname>XColor</structname>
-structure, whose three flags
-(<symbol>DoRed</symbol>,
-<symbol>DoGreen</symbol>,
-and
-<symbol>DoBlue</symbol>)
-are set, in a call to
-<function>XStoreColor</function>
-to change the color cell specified by the pixel member of the
-<structname>XcmsColor</structname>
-structure.
-This pixel value must be a valid index for the specified colormap,
-and the color cell specified by the pixel value must be a read/write cell.
-If the pixel value is not a valid index, a
-<errorname>BadValue</errorname>
-error results.
-If the color cell is unallocated or is allocated read-only, a
-<errorname>BadAccess</errorname>
-error results.
-If the colormap is an installed map for its screen,
-the changes are visible immediately.
-</para>
-<para>
-<!-- .LP -->
-Note that
-<function>XStoreColor</function>
-has no return value; therefore, an
-<symbol>XcmsSuccess</symbol>
-return value from this function indicates that the conversion
-to <acronym>RGB</acronym> succeeded and the call to
-<function>XStoreColor</function>
-was made.
-To obtain the actual color stored, use
-<function>XcmsQueryColor</function>.
-Because of the screen's hardware limitations or gamut compression,
-the color stored in the colormap may not be identical
-to the color specified.
-</para>
-<para>
-<!-- .LP -->
-<function>XcmsStoreColor</function>
-can generate
-<errorname>BadAccess</errorname>,
-<errorname>BadColor</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To store multiple colors of arbitrary format in multiple colormap cells, use
-<function>XcmsStoreColors</function>.
-</para>
-<indexterm><primary>Color</primary><secondary>storing</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsStoreColors</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsStoreColors</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>XcmsColor<parameter> colors[]</parameter></paramdef>
- <paramdef>int<parameter> ncolors</parameter></paramdef>
- <paramdef>Bool<parameter> compression_flags_return[]</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colors</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color specification array of
-<structname>XcmsColor</structname>
-structures, each specifying a color cell and the color to store in that
-cell.
-Values specified in the array remain unchanged upon return.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ncolors</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of
-<structname>XcmsColor</structname>
-structures in the color-specification array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>compression_flags_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns an array of Boolean values indicating compression status.
-If a non-NULL pointer is supplied,
-each element of the array is set to
-<symbol>True</symbol>
-if the corresponding color was compressed and
-<symbol>False</symbol>
-otherwise.
-Pass NULL if the compression status is not useful.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsStoreColors</function>
-function converts the colors specified in the array of
-<structname>XcmsColor</structname>
-structures into <acronym>RGB</acronym> values and then uses these <acronym>RGB</acronym> specifications in
-<structname>XColor</structname>
-structures, whose three flags
-(<symbol>DoRed</symbol>,
-<symbol>DoGreen</symbol>,
-and
-<symbol>DoBlue</symbol>)
-are set, in a call to
-<function>XStoreColors</function>
-to change the color cells specified by the pixel member of the corresponding
-<structname>XcmsColor</structname>
-structure.
-Each pixel value must be a valid index for the specified colormap,
-and the color cell specified by each pixel value must be a read/write cell.
-If a pixel value is not a valid index, a
-<errorname>BadValue</errorname>
-error results.
-If a color cell is unallocated or is allocated read-only, a
-<errorname>BadAccess</errorname>
-error results.
-If more than one pixel is in error,
-the one that gets reported is arbitrary.
-If the colormap is an installed map for its screen,
-the changes are visible immediately.
-</para>
-<para>
-<!-- .LP -->
-Note that
-<function>XStoreColors</function>
-has no return value; therefore, an
-<symbol>XcmsSuccess</symbol>
-return value from this function indicates that conversions
-to <acronym>RGB</acronym> succeeded and the call to
-<function>XStoreColors</function>
-was made.
-To obtain the actual colors stored, use
-<function>XcmsQueryColors</function>.
-Because of the screen's hardware limitations or gamut compression,
-the colors stored in the colormap may not be identical
-to the colors specified.
-</para>
-<para>
-<!-- .LP -->
-<function>XcmsStoreColors</function>
-can generate
-<errorname>BadAccess</errorname>,
-<errorname>BadColor</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To store a color specified by name in a single colormap cell, use
-<function>XStoreNamedColor</function>.
-</para>
-<indexterm><primary>Color</primary><secondary>storing</secondary></indexterm>
-<indexterm><primary>Color</primary><secondary>naming</secondary></indexterm>
-<indexterm significance="preferred"><primary>XStoreNamedColor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XStoreNamedColor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>char<parameter> *color</parameter></paramdef>
- <paramdef>unsignedlong<parameter> pixel</parameter></paramdef>
- <paramdef>int<parameter> flags</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color name string (for example, red).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pixel</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the entry in the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>flags</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which red, green, and blue components are set.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XStoreNamedColor</function>
-function looks up the named color with respect to the screen associated with
-the colormap and stores the result in the specified colormap.
-The pixel argument determines the entry in the colormap.
-The flags argument determines which of the red, green, and blue components
-are set.
-You can set this member to the
-bitwise inclusive OR of the bits
-<symbol>DoRed</symbol>,
-<symbol>DoGreen</symbol>,
-and
-<symbol>DoBlue</symbol>.
-If the color name is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-Use of uppercase or lowercase does not matter.
-If the specified pixel is not a valid index into the colormap, a
-<errorname>BadValue</errorname>
-error results.
-If the specified pixel either is unallocated or is allocated read-only, a
-<errorname>BadAccess</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XStoreNamedColor</function>
-can generate
-<errorname>BadAccess</errorname>,
-<errorname>BadColor</errorname>,
-<errorname>BadName</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-The
-<function>XQueryColor</function>
-and
-<function>XQueryColors</function>
-functions take pixel values in the pixel member of
-<structname>XColor</structname>
-structures and store in the structures the <acronym>RGB</acronym> values for those
-pixels from the specified colormap.
-The values returned for an unallocated entry are undefined.
-These functions also set the flags member in the
-<structname>XColor</structname>
-structure to all three colors.
-If a pixel is not a valid index into the specified colormap, a
-<errorname>BadValue</errorname>
-error results.
-If more than one pixel is in error,
-the one that gets reported is arbitrary.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To query the <acronym>RGB</acronym> value of a single colormap cell, use
-<function>XQueryColor</function>.
-</para>
-<indexterm><primary>Color</primary><secondary>querying</secondary></indexterm>
-<indexterm significance="preferred"><primary>XQueryColor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XQueryColor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>XColor<parameter> *def_in_out</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>def_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies and returns the <acronym>RGB</acronym> values for the pixel specified in the structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XQueryColor</function>
-function returns the current <acronym>RGB</acronym> value for the pixel in the
-<structname>XColor</structname>
-structure and sets the
-<symbol>DoRed</symbol>,
-<symbol>DoGreen</symbol>,
-and
-<symbol>DoBlue</symbol>
-flags.
-</para>
-<para>
-<!-- .LP -->
-<function>XQueryColor</function>
-can generate
-<errorname>BadColor</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To query the <acronym>RGB</acronym> values of multiple colormap cells, use
-<function>XQueryColors</function>.
-</para>
-<indexterm><primary>Color</primary><secondary>querying</secondary></indexterm>
-<indexterm significance="preferred"><primary>XQueryColors</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XQueryColors</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>XColor<parameter> defs_in_out[]</parameter></paramdef>
- <paramdef>int<parameter> ncolors</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>defs_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies and returns an array of color definition structures for the pixel
-specified in the structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ncolors</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .\"Specifies the number of color definition structures. -->
-Specifies the number of
-<structname>XColor</structname>
-structures in the color definition array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XQueryColors</function>
-function returns the <acronym>RGB</acronym> value for each pixel in each
-<structname>XColor</structname>
-structure and sets the
-<symbol>DoRed</symbol>,
-<symbol>DoGreen</symbol>,
-and
-<symbol>DoBlue</symbol>
-flags in each structure.
-
-</para>
-<para>
-<!-- .LP -->
-<function>XQueryColors</function>
-can generate
-<errorname>BadColor</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To query the color of a single colormap cell in an arbitrary format, use
-<function>XcmsQueryColor</function>.
-</para>
-<indexterm><primary>Color</primary><secondary>querying</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsQueryColor</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsQueryColor</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_in_out</parameter></paramdef>
- <paramdef>XcmsColorFormat<parameter> result_format</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the pixel member that indicates the color cell to query.
-The color specification stored for the color cell is returned in this
-<structname>XcmsColor</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>result_format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color format for the returned color specification.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsQueryColor</function>
-function obtains the <acronym>RGB</acronym> value
-for the pixel value in the pixel member of the specified
-<structname>XcmsColor</structname>
-structure and then
-converts the value to the target format as
-specified by the result_format argument.
-If the pixel is not a valid index in the specified colormap, a
-<errorname>BadValue</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XcmsQueryColor</function>
-can generate
-<errorname>BadColor</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To query the color of multiple colormap cells in an arbitrary format, use
-<function>XcmsQueryColors</function>.
-</para>
-<indexterm><primary>Color</primary><secondary>querying</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsQueryColors</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsQueryColors</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>XcmsColor<parameter> colors_in_out[]</parameter></paramdef>
- <paramdef>unsignedint<parameter> ncolors</parameter></paramdef>
- <paramdef>XcmsColorFormat<parameter> result_format</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colors_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of
-<structname>XcmsColor</structname>
-structures, each pixel member indicating the color cell to query.
-The color specifications for the color cells are returned in these structures.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ncolors</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of
-<structname>XcmsColor</structname>
-structures in the color-specification array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>result_format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color format for the returned color specification.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsQueryColors</function>
-function obtains the <acronym>RGB</acronym> values
-for pixel values in the pixel members of
-<structname>XcmsColor</structname>
-structures and then
-converts the values to the target format as
-specified by the result_format argument.
-If a pixel is not a valid index into the specified colormap, a
-<errorname>BadValue</errorname>
-error results.
-If more than one pixel is in error,
-the one that gets reported is arbitrary.
-</para>
-<para>
-<!-- .LP -->
-<function>XcmsQueryColors</function>
-can generate
-<errorname>BadColor</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-</sect1>
-<sect1 id="Color_Conversion_Context_Functions">
-<title>Color Conversion Context Functions</title>
-<!-- .XS -->
-<!-- (SN Color Conversion Context Functions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This section describes functions to create, modify,
-and query Color Conversion Contexts (CCCs).
-</para>
-<para>
-<!-- .LP -->
-Associated with each colormap is an initial CCC transparently generated by
-Xlib.
-<indexterm><primary>Color Conversion Context</primary><secondary>creation</secondary></indexterm>
-Therefore, when you specify a colormap as an argument to a function,
-you are indirectly specifying a CCC.
-<indexterm><primary>CCC</primary><secondary>of colormap</secondary></indexterm>
-<indexterm><primary>Color Conversion Context</primary><secondary>of colormap</secondary></indexterm>
-The CCC attributes that can be modified by the X client are:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Client White Point
- </para>
- </listitem>
- <listitem>
- <para>
-Gamut compression procedure and client data
- </para>
- </listitem>
- <listitem>
- <para>
-White point adjustment procedure and client data
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The initial values for these attributes are implementation specific.
-The CCC attributes for subsequently created CCCs can be defined
-by changing the CCC attributes of the default CCC.
-<indexterm><primary>CCC</primary><secondary>default</secondary></indexterm>
-<indexterm><primary>Color Conversion Context</primary><secondary>default</secondary></indexterm>
-There is a default CCC associated with each screen.
-</para>
-<sect2 id="Getting_and_Setting_the_Color_Conversion_Context_of_a_Colormap">
-<title>Getting and Setting the Color Conversion Context of a Colormap</title>
-<!-- .XS -->
-<!-- (SN Getting and Setting the Color Conversion Context of a Colormap -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the CCC associated with a colormap, use
-<function>XcmsCCCOfColormap</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsCCCOfColormap</primary></indexterm>
-<indexterm><primary>Colormap</primary><secondary>CCC of</secondary></indexterm>
-<indexterm><primary>CCC</primary><secondary>of colormap</secondary></indexterm>
-<indexterm><primary>Color Conversion Context</primary><secondary>of colormap</secondary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XcmsCCC <function>XcmsCCCOfColormap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsCCCOfColormap</function>
-function returns the CCC associated with the specified colormap.
-Once obtained,
-the CCC attributes can be queried or modified.
-Unless the CCC associated with the specified colormap is changed with
-<function>XcmsSetCCCOfColormap</function>,
-this CCC is used when the specified colormap is used as an argument
-to color functions.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To change the CCC associated with a colormap, use
-<function>XcmsSetCCCOfColormap</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsSetCCCOfColormap</primary></indexterm>
-<indexterm><primary>Colormap</primary><secondary>CCC of</secondary></indexterm>
-<indexterm><primary>CCC</primary><secondary>of colormap</secondary></indexterm>
-<indexterm><primary>Color Conversion Context</primary><secondary>of colormap</secondary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XcmsCCC <function>XcmsSetCCCOfColormap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsSetCCCOfColormap</function>
-function changes the CCC associated with the specified colormap.
-It returns the CCC previously associated with the colormap.
-If they are not used again in the application,
-CCCs should be freed by calling
-<function>XcmsFreeCCC</function>.
-Several colormaps may share the same CCC without restriction; this
-includes the CCCs generated by Xlib with each colormap. Xlib, however,
-creates a new CCC with each new colormap.
-</para>
-</sect2>
-<sect2 id="Obtaining_the_Default_Color_Conversion_Context">
-<title>Obtaining the Default Color Conversion Context</title>
-<!-- .XS -->
-<!-- (SN Obtaining the Default Color Conversion Context -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-You can change the default CCC attributes for subsequently created CCCs
-by changing the CCC attributes of the default CCC.
-<indexterm><primary>CCC</primary><secondary>default</secondary></indexterm>
-<indexterm><primary>Color Conversion Context</primary><secondary>default</secondary></indexterm>
-A default CCC is associated with each screen.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the default CCC for a screen, use
-<function>XcmsDefaultCCC</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsDefaultCCC</primary></indexterm>
-<indexterm><primary>Color Conversion Context</primary><secondary>default</secondary></indexterm>
-<indexterm><primary>CCC</primary><secondary>default</secondary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XcmsCCC <function>XcmsDefaultCCC</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> screen_number</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen_number</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the appropriate screen number on the host server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsDefaultCCC</function>
-function returns the default CCC for the specified screen.
-Its visual is the default visual of the screen.
-Its initial gamut compression and white point
-adjustment procedures as well as the associated client data are implementation
-specific.
-</para>
-</sect2>
-<sect2 id="Color_Conversion_Context_Macros">
-<title>Color Conversion Context Macros</title>
-<!-- .XS -->
-<!-- (SN Color Conversion Context Macros -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Applications should not directly modify any part of the
-<structname>XcmsCCC</structname>.
-The following lists the C language macros, their corresponding function
-equivalents for other language bindings, and what data they both
-can return.
-<!-- .sp -->
-</para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>DisplayOfCCC</primary></indexterm>
-<indexterm significance="preferred"><primary>XcmsDisplayOfCCC</primary></indexterm>
-<!-- .sM -->
-
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>DisplayOfCCC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<funcsynopsis>
-<funcprototype>
- <funcdef>Display *<function>XcmsDisplayOfCCC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Both return the display associated with the specified CCC.
-</para>
-<!-- .LP -->
-<!-- .sp -->
-<indexterm significance="preferred"><primary>VisualOfCCC</primary></indexterm>
-<indexterm significance="preferred"><primary>XcmsVisualOfCCC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>VisualOfCCC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<funcsynopsis>
-<funcprototype>
- <funcdef>Visual *<function>XcmsVisualOfCCC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Both return the visual associated with the specified CCC.
-<!-- .sp -->
-</para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>ScreenNumberOfCCC</primary></indexterm>
-<indexterm significance="preferred"><primary>XcmsScreenNumberOfCCC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>ScreenNumberOfCCC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XcmsScreenNumberOfCCC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Both return the number of the screen associated with the specified CCC.
-<!-- .sp -->
-</para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>ScreenWhitePointOfCCC</primary></indexterm>
-<indexterm significance="preferred"><primary>XcmsScreenWhitePointOfCCC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>ScreenWhitePointOfCCC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<funcsynopsis>
-<funcprototype>
- <funcdef>XcmsColor <function>XcmsScreenWhitePointOfCCC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Both return the white point of the screen associated with the specified CCC.
-<!-- .sp -->
-</para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>ClientWhitePointOfCCC</primary></indexterm>
-<indexterm significance="preferred"><primary>XcmsClientWhitePointOfCCC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef> <function>ClientWhitePointOfCCC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<funcsynopsis>
-<funcprototype>
- <funcdef>XcmsColor *<function>XcmsClientWhitePointOfCCC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Both return the Client White Point of the specified CCC.
-</para>
-</sect2>
-
-<sect2 id="Modifying_Attributes_of_a_Color_Conversion_Context">
-<title>Modifying Attributes of a Color Conversion Context</title>
-<!-- .XS -->
-<!-- (SN Modifying Attributes of a Color Conversion Context -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To set the Client White Point in the CCC, use
-<function>XcmsSetWhitePoint</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsSetWhitePoint</primary></indexterm>
-<indexterm><primary>Client White Point</primary><secondary>of Color Conversion Context</secondary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsSetWhitePoint</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-<!-- .ds Co new Client White Point -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the new Client White Point.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsSetWhitePoint</function>
-function changes the Client White Point in the specified CCC.
-Note that the pixel member is ignored
-and that the color specification is left unchanged upon return.
-The format for the new white point must be
-<symbol>XcmsCIEXYZFormat</symbol>,
-<symbol>XcmsCIEuvYFormat</symbol>,
-<symbol>XcmsCIExyYFormat</symbol>,
-or
-<symbol>XcmsUndefinedFormat</symbol>.
-If the color argument is NULL, this function sets the format component of the
-Client White Point specification to
-<symbol>XcmsUndefinedFormat</symbol>,
-indicating that the Client White Point is assumed to be the same as the
-Screen White Point.
-</para>
-<para>
-<!-- .LP -->
-This function returns nonzero status
-if the format for the new white point is valid;
-otherwise, it returns zero.
-
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set the gamut compression procedure and corresponding client data
-in a specified CCC, use
-<function>XcmsSetCompressionProc</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsSetCompressionProc</primary></indexterm>
-<indexterm><primary>Gamut compression</primary><secondary>setting in Color Conversion Context</secondary></indexterm>
-<indexterm><primary>Gamut compression</primary><secondary>procedure</secondary></indexterm>
-<indexterm><primary>Gamut compression</primary><secondary>client data</secondary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XcmsCompressionProc <function>XcmsSetCompressionProc</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsCompressionProc<parameter> compression_proc</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>compression_proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the gamut compression procedure that is to be applied
-when a color lies outside the screen's color gamut.
-If NULL is specified and a function using this CCC must convert
-a color specification to a device-dependent format and encounters a color
-that lies outside the screen's color gamut,
-that function will return
-<symbol>XcmsFailure</symbol>.
-<!-- .ds Cd the gamut compression procedure -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies client data for gamut compression procedure or NULL.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsSetCompressionProc</function>
-function first sets the gamut compression procedure and client data
-in the specified CCC with the newly specified procedure and client data
-and then returns the old procedure.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set the white point adjustment procedure and corresponding client data
-in a specified CCC, use
-<function>XcmsSetWhiteAdjustProc</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsSetWhiteAdjustProc</primary></indexterm>
-<indexterm><primary>White point adjustment</primary><secondary>setting in Color Conversion Context</secondary></indexterm>
-<indexterm><primary>White point adjustment</primary><secondary>procedure</secondary></indexterm>
-<indexterm><primary>White point adjustment</primary><secondary>client data</secondary></indexterm>
-<funcsynopsis>
-<funcprototype>
- <funcdef>XcmsWhiteAdjustProc <function>XcmsSetWhiteAdjustProc</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsWhiteAdjustProc<parameter> white_adjust_proc</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>white_adjust_proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the white point adjustment procedure.
-<!-- .ds Cd the white point adjustment procedure -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies client data for white point adjustment procedure or NULL.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsSetWhiteAdjustProc</function>
-function first sets the white point adjustment procedure and client data
-in the specified CCC with the newly specified procedure and client data
-and then returns the old procedure.
-</para>
-</sect2>
-<sect2 id="Creating_and_Freeing_a_Color_Conversion_Context">
-<title>Creating and Freeing a Color Conversion Context</title>
-<!-- .XS -->
-<!-- (SN Creating and Freeing a Color Conversion Context -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-You can explicitly create a CCC within your application by calling
-<function>XcmsCreateCCC</function>.
-These created CCCs can then be used by those functions that explicitly
-call for a CCC argument.
-Old CCCs that will not be used by the application should be freed using
-<function>XcmsFreeCCC</function>.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To create a CCC, use
-<function>XcmsCreateCCC</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsCreateCCC</primary></indexterm>
-<indexterm><primary>Color Conversion Context</primary><secondary>creation</secondary></indexterm>
-<indexterm><primary>CCC</primary><secondary>creation</secondary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XcmsCCC <function>XcmsCreateCCC</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> screen_number</parameter></paramdef>
- <paramdef>Visual<parameter> *visual</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *client_white_point</parameter></paramdef>
- <paramdef>XcmsCompressionProc<parameter> compression_proc</parameter></paramdef>
- <paramdef>XPointer<parameter> compression_client_data</parameter></paramdef>
- <paramdef>XcmsWhiteAdjustProc<parameter> white_adjust_proc</parameter></paramdef>
- <paramdef>XPointer<parameter> white_adjust_client_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen_number</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the appropriate screen number on the host server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>visual</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the visual type.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_white_point</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the Client White Point.
-If NULL is specified,
-the Client White Point is to be assumed to be the same as the
-Screen White Point.
-Note that the pixel member is ignored.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>compression_proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the gamut compression procedure that is to be applied
-when a color lies outside the screen's color gamut.
-If NULL is specified and a function using this CCC must convert
-a color specification to a device-dependent format and encounters a color
-that lies outside the screen's color gamut,
-that function will return
-<symbol>XcmsFailure</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>compression_client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies client data for use by the gamut compression procedure or NULL.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>white_adjust_proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the white adjustment procedure that is to be applied
-when the Client White Point differs from the Screen White Point.
-NULL indicates that no white point adjustment is desired.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>white_adjust_client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies client data for use with the white point adjustment procedure or NULL.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsCreateCCC</function>
-function creates a CCC for the specified display, screen, and visual.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To free a CCC, use
-<function>XcmsFreeCCC</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsFreeCCC</primary></indexterm>
-<indexterm><primary>Color Conversion Context</primary><secondary>freeing</secondary></indexterm>
-<indexterm><primary>CCC</primary><secondary>freeing</secondary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XcmsFreeCCC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsFreeCCC</function>
-function frees the memory used for the specified CCC.
-Note that default CCCs and those currently associated with colormaps
-are ignored.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Converting_between_Color_Spaces">
-<title>Converting between Color Spaces</title>
-<!-- .XS -->
-<!-- (SN Converting between Color Spaces -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To convert an array of color specifications in arbitrary color formats
-to a single destination format, use
-<function>XcmsConvertColors</function>.
-</para>
-<indexterm><primary>Color conversion</primary></indexterm>
-<indexterm><primary>Color</primary><secondary>conversion</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsConvertColors</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsConvertColors</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsColor<parameter> colors_in_out[]</parameter></paramdef>
- <paramdef>unsignedint<parameter> ncolors</parameter></paramdef>
- <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
- <paramdef>Bool<parameter> compression_flags_return[]</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-If conversion is between device-independent color spaces only
-(for example, TekHVC to CIELuv),
-the CCC is necessary only to specify the Client White Point.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colors_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of color specifications.
-Pixel members are ignored and remain unchanged upon return.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ncolors</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of
-<structname>XcmsColor</structname>
-structures in the color-specification array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>target_format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the target color specification format.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>compression_flags_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns an array of Boolean values indicating compression status.
-If a non-NULL pointer is supplied,
-each element of the array is set to
-<symbol>True</symbol>
-if the corresponding color was compressed and
-<symbol>False</symbol>
-otherwise.
-Pass NULL if the compression status is not useful.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsConvertColors</function>
-function converts the color specifications in the specified array of
-<structname>XcmsColor</structname>
-structures from their current format to a single target format,
-using the specified CCC.
-When the return value is
-<symbol>XcmsFailure</symbol>,
-the contents of the color specification array are left unchanged.
-</para>
-<para>
-<!-- .LP -->
-The array may contain a mixture of color specification formats
-(for example, 3 <acronym>CIE</acronym> XYZ, 2 <acronym>CIE</acronym> Luv, and so on).
-When the array contains both device-independent and
-device-dependent color specifications and the target_format argument specifies
-a device-dependent format (for example,
-<symbol>XcmsRGBiFormat</symbol>,
-<symbol>XcmsRGBFormat</symbol>),
-all specifications are converted to <acronym>CIE</acronym> XYZ format and then to the target
-device-dependent format.
-</para>
-</sect1>
-<sect1 id="Callback_Functions">
-<title>Callback Functions</title>
-<!-- .XS -->
-<!-- (SN Callback Functions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This section describes the gamut compression and white point
-adjustment callbacks.
-</para>
-<para>
-<!-- .LP -->
-The gamut compression procedure specified in the CCC
-is called when an attempt to convert a color specification from
-<structname>XcmsCIEXYZ</structname>
-to a device-dependent format (typically
-<structname>XcmsRGBi</structname>)
-results in a color that lies outside the screen's color gamut.
-If the gamut compression procedure requires client data, this data is passed
-via the gamut compression client data in the CCC.
-</para>
-<para>
-<!-- .LP -->
-During color specification conversion between device-independent
-and device-dependent color spaces,
-if a white point adjustment procedure is specified in the CCC,
-it is triggered when the Client White Point and Screen White Point differ.
-If required, the client data is obtained from the CCC.
-</para>
-<sect2 id="Prototype_Gamut_Compression_Procedure">
-<title>Prototype Gamut Compression Procedure</title>
-<!-- .XS -->
-<!-- (SN Prototype Gamut Compression Procedure -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The gamut compression callback interface must adhere to the
-following:
-</para>
-<indexterm significance="preferred"><primary>XcmsCompressionProc</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>typedef Status<function>(*XcmsCompressionProc</function>)</funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsColor<parameter> colors_in_out[]</parameter></paramdef>
- <paramdef>unsignedint<parameter> ncolors</parameter></paramdef>
- <paramdef>unsignedint<parameter> index</parameter></paramdef>
- <paramdef>Bool<parameter> compression_flags_return[]</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colors_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of color specifications.
-Pixel members should be ignored and must remain unchanged upon return.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ncolors</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of
-<structname>XcmsColor</structname>
-structures in the color-specification array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>index</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the index into the array of
-<structname>XcmsColor</structname>
-structures for the encountered color specification that lies outside the
-screen's color gamut.
-Valid values are 0 (for the first element) to ncolors - 1.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>compression_flags_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns an array of Boolean values for indicating compression status.
-If a non-NULL pointer is supplied
-and a color at a given index is compressed, then
-<symbol>True</symbol>
-should be stored at the corresponding index in this array;
-otherwise, the array should not be modified.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-When implementing a gamut compression procedure, consider the following
-rules and assumptions:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The gamut compression procedure can attempt to compress one or multiple
-specifications at a time.
- </para>
- </listitem>
- <listitem>
- <para>
-When called, elements 0 to index - 1 in the color specification
-array can be assumed to fall within the screen's color gamut.
-In addition, these color specifications are already in some device-dependent
-format (typically
-<structname>XcmsRGBi</structname>).
-If any modifications are made to these color specifications,
-they must be in their initial device-dependent format upon return.
- </para>
- </listitem>
- <listitem>
- <para>
-When called, the element in the color specification array specified
-by the index argument contains the color specification outside the
-screen's color gamut encountered by the calling routine.
-In addition, this color specification can be assumed to be in
-<structname>XcmsCIEXYZ</structname>.
-Upon return, this color specification must be in
-<structname>XcmsCIEXYZ</structname>.
- </para>
- </listitem>
- <listitem>
- <para>
-When called, elements from index to ncolors - 1
-in the color specification array may or may not fall within the
-screen's color gamut.
-In addition, these color specifications can be assumed to be in
-<structname>XcmsCIEXYZ</structname>.
-If any modifications are made to these color specifications,
-they must be in
-<structname>XcmsCIEXYZ</structname>
-upon return.
- </para>
- </listitem>
- <listitem>
- <para>
-The color specifications passed to the gamut compression procedure
-have already been adjusted to the Screen White Point.
-This means that at this point the color specification's white point
-is the Screen White Point.
- </para>
- </listitem>
- <listitem>
- <para>
-If the gamut compression procedure uses a device-independent color space not
-initially accessible for use in the color management system, use
-<function>XcmsAddColorSpace</function>
-to ensure that it is added.
- </para>
- </listitem>
-</itemizedlist>
-</sect2>
-<sect2 id="Supplied_Gamut_Compression_Procedures">
-<title>Supplied Gamut Compression Procedures</title>
-<!-- .XS -->
-<!-- (SN Supplied Gamut Compression Procedures -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The following equations are useful in describing gamut compression
-functions:
-<!-- .EQ -->
-delim %%
-<!-- .EN -->
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-%CIELab~Psychometric~Chroma ~=~ sqrt(a_star sup 2 ~+~ b_star sup 2 )%
-
-%CIELab~Psychometric~Hue ~=~ tan sup -1 left [ b_star over a_star right ]%
-
-%CIELuv~Psychometric~Chroma ~=~ sqrt(u_star sup 2 ~+~ v_star sup 2 )%
-
-%CIELuv~Psychometric~Hue ~=~ tan sup -1 left [ v_star over u_star right ]%
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The gamut compression callback procedures provided by Xlib are as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-<function>XcmsCIELabClipL</function>
- </para>
- </listitem>
- <listitem>
- <para>
-This brings the encountered out-of-gamut color specification into the
-screen's color gamut by reducing or increasing <acronym>CIE</acronym> metric lightness (L*)
-in the <acronym>CIE</acronym> L*a*b* color space until the color is within the gamut.
-If the Psychometric Chroma of the color specification
-is beyond maximum for the Psychometric Hue Angle,
-then while maintaining the same Psychometric Hue Angle,
-the color will be clipped to the <acronym>CIE</acronym> L*a*b* coordinates of maximum
-Psychometric Chroma.
-See
-<function>XcmsCIELabQueryMaxC</function>.
-No client data is necessary.
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XcmsCIELabClipab</function>
- </para>
- </listitem>
- <listitem>
- <para>
-This brings the encountered out-of-gamut color specification into the
-screen's color gamut by reducing Psychometric Chroma,
-while maintaining Psychometric Hue Angle,
-until the color is within the gamut.
-No client data is necessary.
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XcmsCIELabClipLab</function>
- </para>
- </listitem>
- <listitem>
- <para>
-This brings the encountered out-of-gamut color specification into the
-screen's color gamut by replacing it with <acronym>CIE</acronym> L*a*b* coordinates
-that fall within the color gamut while maintaining the original
-Psychometric Hue
-Angle and whose vector to the original coordinates is the shortest attainable.
-No client data is necessary.
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XcmsCIELuvClipL</function>
- </para>
- </listitem>
- <listitem>
- <para>
-This brings the encountered out-of-gamut color specification into the
-screen's color gamut by reducing or increasing <acronym>CIE</acronym> metric lightness (L*)
-in the <acronym>CIE</acronym> L*u*v* color space until the color is within the gamut.
-If the Psychometric Chroma of the color specification
-is beyond maximum for the Psychometric Hue Angle,
-then, while maintaining the same Psychometric Hue Angle,
-the color will be clipped to the <acronym>CIE</acronym> L*u*v* coordinates of maximum
-Psychometric Chroma.
-See
-<function>XcmsCIELuvQueryMaxC</function>.
-No client data is necessary.
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XcmsCIELuvClipuv</function>
- </para>
- </listitem>
- <listitem>
- <para>
-This brings the encountered out-of-gamut color specification into the
-screen's color gamut by reducing
-Psychometric Chroma, while maintaining Psychometric Hue Angle,
-until the color is within the gamut.
-No client data is necessary.
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XcmsCIELuvClipLuv</function>
- </para>
- </listitem>
- <listitem>
- <para>
-This brings the encountered out-of-gamut color specification into the
-screen's color gamut by replacing it with <acronym>CIE</acronym> L*u*v* coordinates
-that fall within the color gamut while maintaining the original
-Psychometric Hue
-Angle and whose vector to the original coordinates is the shortest attainable.
-No client data is necessary.
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XcmsTekHVCClipV</function>
- </para>
- </listitem>
- <listitem>
- <para>
-This brings the encountered out-of-gamut color specification into the
-screen's color gamut by reducing or increasing the Value dimension
-in the TekHVC color space until the color is within the gamut.
-If Chroma of the color specification is beyond maximum for the particular Hue,
-then, while maintaining the same Hue,
-the color will be clipped to the Value and Chroma coordinates
-that represent maximum Chroma for that particular Hue.
-No client data is necessary.
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XcmsTekHVCClipC</function>
- </para>
- </listitem>
- <listitem>
- <para>
-This brings the encountered out-of-gamut color specification into the
-screen's color gamut by reducing the Chroma dimension
-in the TekHVC color space until the color is within the gamut.
-No client data is necessary.
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XcmsTekHVCClipVC</function>
- </para>
- </listitem>
- <listitem>
- <para>
-This brings the encountered out-of-gamut color specification into the
-screen's color gamut by replacing it with TekHVC coordinates
-that fall within the color gamut while maintaining the original Hue
-and whose vector to the original coordinates is the shortest attainable.
-No client data is necessary.
- </para>
- </listitem>
-</itemizedlist>
-</sect2>
-<sect2 id="Prototype_White_Point_Adjustment_Procedure">
-<title>Prototype White Point Adjustment Procedure</title>
-<!-- .XS -->
-<!-- (SN Prototype White Point Adjustment Procedure -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The white point adjustment procedure interface must adhere to the following:
-</para>
-<indexterm significance="preferred"><primary>XcmsWhiteAdjustProc</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>typedef Status <function>(*XcmsWhiteAdjustProc</function>)</funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *initial_white_point</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *target_white_point</parameter></paramdef>
- <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
- <paramdef>XcmsColor<parameter> colors_in_out[]</parameter></paramdef>
- <paramdef>unsignedint<parameter> ncolors</parameter></paramdef>
- <paramdef>Bool<parameter> compression_flags_return[]</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>initial_white_point</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the initial white point.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>target_white_point</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the target white point.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>target_format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the target color specification format.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colors_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of color specifications.
-Pixel members should be ignored and must remain unchanged upon return.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ncolors</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of
-<structname>XcmsColor</structname>
-structures in the color-specification array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>compression_flags_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns an array of Boolean values for indicating compression status.
-If a non-NULL pointer is supplied
-and a color at a given index is compressed, then
-<symbol>True</symbol>
-should be stored at the corresponding index in this array;
-otherwise, the array should not be modified.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-</para>
-</sect2>
-<sect2 id="Supplied_White_Point_Adjustment_Procedures">
-<title>Supplied White Point Adjustment Procedures</title>
-<!-- .XS -->
-<!-- (SN Supplied White Point Adjustment Procedures -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-White point adjustment procedures provided by Xlib are as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-<function>XcmsCIELabWhiteShiftColors</function>
- </para>
- </listitem>
- <listitem>
- <para>
-This uses the <acronym>CIE</acronym> L*a*b* color space for adjusting the chromatic character
-of colors to compensate for the chromatic differences between the source
-and destination white points.
-This procedure simply converts the color specifications to
-<structname>XcmsCIELab</structname>
-using the source white point and then converts to the target specification
-format using the destination's white point.
-No client data is necessary.
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XcmsCIELuvWhiteShiftColors</function>
- </para>
- </listitem>
- <listitem>
- <para>
-This uses the <acronym>CIE</acronym> L*u*v* color space for adjusting the chromatic character
-of colors to compensate for the chromatic differences between the source
-and destination white points.
-This procedure simply converts the color specifications to
-<structname>XcmsCIELuv</structname>
-using the source white point and then converts to the target specification
-format using the destination's white point.
-No client data is necessary.
- </para>
- </listitem>
- <listitem>
- <para>
-<function>XcmsTekHVCWhiteShiftColors</function>
- </para>
- </listitem>
- <listitem>
- <para>
-This uses the TekHVC color space for adjusting the chromatic character
-of colors to compensate for the chromatic differences between the source
-and destination white points.
-This procedure simply converts the color specifications to
-<structname>XcmsTekHVC</structname>
-using the source white point and then converts to the target specification
-format using the destination's white point.
-An advantage of this procedure over those previously described
-is an attempt to minimize hue shift.
-No client data is necessary.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-From an implementation point of view,
-these white point adjustment procedures convert the color specifications
-to a device-independent but white-point-dependent color space
-(for example, <acronym>CIE</acronym> L*u*v*, <acronym>CIE</acronym> L*a*b*, TekHVC) using one white point
-and then converting those specifications to the target color space
-using another white point.
-In other words,
-the specification goes in the color space with one white point
-but comes out with another white point,
-resulting in a chromatic shift based on the chromatic displacement
-between the initial white point and target white point.
-The <acronym>CIE</acronym> color spaces that are assumed to be white-point-independent
-are <acronym>CIE</acronym> u'v'Y, <acronym>CIE</acronym> XYZ, and <acronym>CIE</acronym> xyY.
-When developing a custom white point adjustment procedure that uses a
-device-independent color space not initially accessible for use in the
-color management system, use
-<function>XcmsAddColorSpace</function>
-to ensure that it is added.
-</para>
-<para>
-<!-- .LP -->
-As an example,
-if the CCC specifies a white point adjustment procedure
-and if the Client White Point and Screen White Point differ, the
-<function>XcmsAllocColor</function>
-function will use the white point adjustment
-procedure twice:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Once to convert to
-<structname>XcmsRGB</structname>
- </para>
- </listitem>
- <listitem>
- <para>
-A second time to convert from
-<structname>XcmsRGB</structname>
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-For example, assume the specification is in
-<structname>XcmsCIEuvY</structname>
-and the adjustment procedure is
-<function>XcmsCIELuvWhiteShiftColors</function>.
-During conversion to
-<structname>XcmsRGB</structname>,
-the call to
-<function>XcmsAllocColor</function>
-results in the following series of color specification conversions:
-<!-- .\" Do these need to be font coded? -->
-</para>
-<itemizedlist>
- <listitem>
- <para>
-From
-<structname>XcmsCIEuvY</structname>
-to
-<structname>XcmsCIELuv</structname>
-using the Client White Point
- </para>
- </listitem>
- <listitem>
- <para>
-From
-<structname>XcmsCIELuv</structname>
-to
-<structname>XcmsCIEuvY</structname>
-using the Screen White Point
- </para>
- </listitem>
- <listitem>
- <para>
-From
-<structname>XcmsCIEuvY</structname>
-to
-<structname>XcmsCIEXYZ</structname>
-(<acronym>CIE</acronym> u'v'Y and XYZ are white-point-independent color spaces)
- </para>
- </listitem>
- <listitem>
- <para>
-From
-<structname>XcmsCIEXYZ</structname>
-to
-<structname>XcmsRGBi</structname>
- </para>
- </listitem>
- <listitem>
- <para>
-From
-<structname>XcmsRGBi</structname>
-to
-<structname>XcmsRGB</structname>
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The resulting <acronym>RGB</acronym> specification is passed to
-<function>XAllocColor</function>,
-and the <acronym>RGB</acronym>
-specification returned by
-<function>XAllocColor</function>
-is converted back to
-<structname>XcmsCIEuvY</structname>
-by reversing the color conversion sequence.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Gamut_Querying_Functions">
-<title>Gamut Querying Functions</title>
-<!-- .XS -->
-<!-- (SN Gamut Querying Functions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This section describes the gamut querying functions that Xlib provides.
-These functions allow the client to query the boundary
-of the screen's color gamut in terms of the <acronym>CIE</acronym> L*a*b*, <acronym>CIE</acronym> L*u*v*,
-and TekHVC color spaces.
-<indexterm><primary>Gamut querying</primary></indexterm>
-Functions are also provided that allow you to query
-the color specification of:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-White (full-intensity red, green, and blue)
- </para>
- </listitem>
- <listitem>
- <para>
-Red (full-intensity red while green and blue are zero)
- </para>
- </listitem>
- <listitem>
- <para>
-Green (full-intensity green while red and blue are zero)
- </para>
- </listitem>
- <listitem>
- <para>
-Blue (full-intensity blue while red and green are zero)
- </para>
- </listitem>
- <listitem>
- <para>
-Black (zero-intensity red, green, and blue)
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The white point associated with color specifications passed to
-and returned from these gamut querying
-functions is assumed to be the Screen White Point.
-<indexterm><primary>Screen White Point</primary></indexterm>
-This is a reasonable assumption,
-because the client is trying to query the screen's color gamut.
-</para>
-<para>
-<!-- .LP -->
-The following naming convention is used for the Max and Min functions:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-Xcms<emphasis remap='I'>&lt;color_space&gt;</emphasis>QueryMax<emphasis remap='I'>&lt;dimensions&gt;</emphasis>
-
-Xcms<emphasis remap='I'>&lt;color_space&gt;</emphasis>QueryMin<emphasis remap='I'>&lt;dimensions&gt;</emphasis>
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The &lt;dimensions&gt; consists of a letter or letters
-that identify the dimensions of the color space
-that are not fixed.
-For example,
-<function>XcmsTekHVCQueryMaxC</function>
-is given a fixed Hue and Value for which maximum Chroma is found.
-</para>
-<sect2 id="Red_Green_and_Blue_Queries">
-<title>Red, Green, and Blue Queries</title>
-<!-- .XS -->
-<!-- (SN Red, Green, and Blue Queries -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To obtain the color specification for black
-(zero-intensity red, green, and blue), use
-<function>XcmsQueryBlack</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsQueryBlack</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsQueryBlack</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>target_format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the target color specification format.
-<!-- .ds Cs zero-intensity red, green, and blue -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the color specification in the specified target format
-for (Cs.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsQueryBlack</function>
-function returns the color specification in the specified target format
-for zero-intensity red, green, and blue.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the color specification for blue
-(full-intensity blue while red and green are zero), use
-<function>XcmsQueryBlue</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsQueryBlue</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsQueryBlue</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>target_format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the target color specification format.
-<!-- .ds Cs full-intensity blue while red and green are zero -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the color specification in the specified target format
-for (Cs.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsQueryBlue</function>
-function returns the color specification in the specified target format
-for full-intensity blue while red and green are zero.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the color specification for green
-(full-intensity green while red and blue are zero), use
-<function>XcmsQueryGreen</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsQueryGreen</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsQueryGreen</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>target_format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the target color specification format.
-<!-- .ds Cs full-intensity green while red and blue are zero -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the color specification in the specified target format
-for (Cs.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsQueryGreen</function>
-function returns the color specification in the specified target format
-for full-intensity green while red and blue are zero.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the color specification for red
-(full-intensity red while green and blue are zero), use
-<function>XcmsQueryRed</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsQueryRed</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsQueryRed</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>target_format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the target color specification format.
-<!-- .ds Cs full-intensity red while green and blue are zero -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the color specification in the specified target format
-for (Cs.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsQueryRed</function>
-function returns the color specification in the specified target format
-for full-intensity red while green and blue are zero.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the color specification for white
-(full-intensity red, green, and blue), use
-<function>XcmsQueryWhite</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsQueryWhite</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsQueryWhite</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>target_format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the target color specification format.
-<!-- .ds Cs full-intensity red, green, and blue -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the color specification in the specified target format
-for (Cs.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsQueryWhite</function>
-function returns the color specification in the specified target format
-for full-intensity red, green, and blue.
-</para>
-</sect2>
-<sect2 id="CIELab_Queries">
-<title>CIELab Queries</title>
-<!-- .XS -->
-<!-- (SN CIELab Queries -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The following equations are useful in describing the CIELab query functions:
-<!-- .EQ -->
-delim %%
-<!-- .EN -->
-</para>
-<para>
-<!-- .LP -->
-<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
-<indexterm><primary>Psychometric Chroma</primary></indexterm>
-<indexterm><primary>Psychometric Chroma</primary><secondary>maximum</secondary></indexterm>
-<literallayout class="monospaced">
-%CIELab~Psychometric~Chroma ~=~ sqrt(a_star sup 2 ~+~ b_star sup 2 )%
-
-%CIELab~Psychometric~Hue ~=~ tan sup -1 left [ b_star over a_star right ]%
-</literallayout>
-<!-- .sp -->
-To obtain the <acronym>CIE</acronym> L*a*b* coordinates of maximum Psychometric Chroma
-for a given Psychometric Hue Angle and <acronym>CIE</acronym> metric lightness (L*), use
-<function>XcmsCIELabQueryMaxC</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsCIELabQueryMaxC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsCIELabQueryMaxC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> L_star</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Ha maximum chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue_angle</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the hue angle (in degrees) at which to find (Ha.
-<!-- .ds Ls maximum chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>L_star</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the lightness (L*) at which to find (Ls.
-<!-- .ds Lc maximum chroma -->
-<!-- .ds lC hue angle and lightness -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the <acronym>CIE</acronym> L*a*b* coordinates of (Lc
-displayable by the screen for the given (lC.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsCIELabQueryMaxC</function>
-function, given a hue angle and lightness,
-finds the point of maximum chroma displayable by the screen.
-It returns this point in <acronym>CIE</acronym> L*a*b* coordinates.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the <acronym>CIE</acronym> L*a*b* coordinates of maximum <acronym>CIE</acronym> metric lightness (L*)
-for a given Psychometric Hue Angle and Psychometric Chroma, use
-<function>XcmsCIELabQueryMaxL</function>.
-</para>
-<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary><secondary>maximum</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsCIELabQueryMaxL</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsCIELabQueryMaxL</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> chroma</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Ha maximum lightness -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue_angle</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the hue angle (in degrees) at which to find (Ha.
-<!-- .ds Ch maximum lightness -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>chroma</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the chroma at which to find (Ch.
-<!-- .ds Lc maximum lightness -->
-<!-- .ds lC hue angle and chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the <acronym>CIE</acronym> L*a*b* coordinates of (Lc
-displayable by the screen for the given (lC.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsCIELabQueryMaxL</function>
-function, given a hue angle and chroma,
-finds the point in <acronym>CIE</acronym> L*a*b* color space of maximum
-lightness (L*) displayable by the screen.
-It returns this point in <acronym>CIE</acronym> L*a*b* coordinates.
-An
-<symbol>XcmsFailure</symbol>
-return value usually indicates that the given chroma
-is beyond maximum for the given hue angle.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the <acronym>CIE</acronym> L*a*b* coordinates of maximum Psychometric Chroma
-for a given Psychometric Hue Angle, use
-<function>XcmsCIELabQueryMaxLC</function>.
-</para>
-<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
-<indexterm><primary>Psychometric Chroma</primary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
-<indexterm><primary>Psychometric Chroma</primary><secondary>maximum</secondary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary><secondary>maximum</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsCIELabQueryMaxLC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsCIELabQueryMaxLC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Ha maximum chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue_angle</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the hue angle (in degrees) at which to find (Ha.
-<!-- .ds Lc maximum chroma -->
-<!-- .ds lC hue angle -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the <acronym>CIE</acronym> L*a*b* coordinates of (Lc
-displayable by the screen for the given (lC.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsCIELabQueryMaxLC</function>
-function, given a hue angle,
-finds the point of maximum chroma displayable by the screen.
-It returns this point in <acronym>CIE</acronym> L*a*b* coordinates.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the <acronym>CIE</acronym> L*a*b* coordinates of minimum <acronym>CIE</acronym> metric lightness (L*)
-for a given Psychometric Hue Angle and Psychometric Chroma, use
-<function>XcmsCIELabQueryMinL</function>.
-</para>
-<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary><secondary>minimum</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsCIELabQueryMinL</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsCIELabQueryMinL</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> chroma</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Ha minimum lightness -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue_angle</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the hue angle (in degrees) at which to find (Ha.
-<!-- .ds Ch minimum lightness -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>chroma</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the chroma at which to find (Ch.
-<!-- .ds Lc minimum lightness -->
-<!-- .ds lC hue angle and chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the <acronym>CIE</acronym> L*a*b* coordinates of (Lc
-displayable by the screen for the given (lC.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsCIELabQueryMinL</function>
-function, given a hue angle and chroma,
-finds the point of minimum lightness (L*) displayable by the screen.
-It returns this point in <acronym>CIE</acronym> L*a*b* coordinates.
-An
-<symbol>XcmsFailure</symbol>
-return value usually indicates that the given chroma
-is beyond maximum for the given hue angle.
-</para>
-</sect2>
-<sect2 id="CIELuv_Queries">
-<title>CIELuv Queries</title>
-<!-- .XS -->
-<!-- (SN CIELuv Queries -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The following equations are useful in describing the CIELuv query functions:
-<!-- .EQ -->
-delim %%
-<!-- .EN -->
-</para>
-<para>
-<!-- .LP -->
-<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
-<indexterm><primary>Psychometric Chroma</primary></indexterm>
-<indexterm><primary>Psychometric Chroma</primary><secondary>maximum</secondary></indexterm>
-<literallayout class="monospaced">
-%CIELuv~Psychometric~Chroma ~=~ sqrt(u_star sup 2 ~+~ v_star sup 2 )%
-
-%CIELuv~Psychometric~Hue ~=~ tan sup -1 left [ v_star over u_star right ]%
-</literallayout>
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the <acronym>CIE</acronym> L*u*v* coordinates of maximum Psychometric Chroma
-for a given Psychometric Hue Angle and <acronym>CIE</acronym> metric lightness (L*), use
-<function>XcmsCIELuvQueryMaxC</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsCIELuvQueryMaxC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsCIELuvQueryMaxC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> L_star</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Ha maximum chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue_angle</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the hue angle (in degrees) at which to find (Ha.
-<!-- .ds Ls maximum chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>L_star</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the lightness (L*) at which to find (Ls.
-<!-- .ds Lc maximum chroma -->
-<!-- .ds lC hue angle and lightness -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the <acronym>CIE</acronym> L*u*v* coordinates of (Lc
-displayable by the screen for the given (lC.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsCIELuvQueryMaxC</function>
-function, given a hue angle and lightness,
-finds the point of maximum chroma displayable by the screen.
-It returns this point in <acronym>CIE</acronym> L*u*v* coordinates.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the <acronym>CIE</acronym> L*u*v* coordinates of maximum <acronym>CIE</acronym> metric lightness (L*)
-for a given Psychometric Hue Angle and Psychometric Chroma, use
-<function>XcmsCIELuvQueryMaxL</function>.
-</para>
-<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary><secondary>maximum</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsCIELuvQueryMaxL</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsCIELuvQueryMaxL</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> chroma</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Ha maximum lightness -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue_angle</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the hue angle (in degrees) at which to find (Ha.
-<!-- .ds Ls maximum lightness -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>L_star</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the lightness (L*) at which to find (Ls.
-<!-- .ds Lc maximum lightness -->
-<!-- .ds lC hue angle and chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the <acronym>CIE</acronym> L*u*v* coordinates of (Lc
-displayable by the screen for the given (lC.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsCIELuvQueryMaxL</function>
-function, given a hue angle and chroma,
-finds the point in <acronym>CIE</acronym> L*u*v* color space of maximum
-lightness (L*) displayable by the screen.
-It returns this point in <acronym>CIE</acronym> L*u*v* coordinates.
-An
-<symbol>XcmsFailure</symbol>
-return value usually indicates that the given chroma
-is beyond maximum for the given hue angle.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the <acronym>CIE</acronym> L*u*v* coordinates of maximum Psychometric Chroma
-for a given Psychometric Hue Angle, use
-<function>XcmsCIELuvQueryMaxLC</function>.
-</para>
-<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
-<indexterm><primary>Psychometric Chroma</primary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
-<indexterm><primary>Psychometric Chroma</primary><secondary>maximum</secondary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary><secondary>maximum</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsCIELuvQueryMaxLC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsCIELuvQueryMaxLC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Ha maximum chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue_angle</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the hue angle (in degrees) at which to find (Ha.
-<!-- .ds Lc maximum chroma -->
-<!-- .ds lC hue angle -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the <acronym>CIE</acronym> L*u*v* coordinates of (Lc
-displayable by the screen for the given (lC.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsCIELuvQueryMaxLC</function>
-function, given a hue angle,
-finds the point of maximum chroma displayable by the screen.
-It returns this point in <acronym>CIE</acronym> L*u*v* coordinates.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the <acronym>CIE</acronym> L*u*v* coordinates of minimum <acronym>CIE</acronym> metric lightness (L*)
-for a given Psychometric Hue Angle and Psychometric Chroma, use
-<function>XcmsCIELuvQueryMinL</function>.
-</para>
-<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
-<indexterm><primary><acronym>CIE</acronym> metric lightness</primary><secondary>minimum</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsCIELuvQueryMinL</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsCIELuvQueryMinL</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> chroma</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Ha minimum lightness -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue_angle</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the hue angle (in degrees) at which to find (Ha.
-<!-- .ds Ch minimum lightness -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>chroma</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the chroma at which to find (Ch.
-<!-- .ds Lc minimum lightness -->
-<!-- .ds lC hue angle and chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the <acronym>CIE</acronym> L*u*v* coordinates of (Lc
-displayable by the screen for the given (lC.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsCIELuvQueryMinL</function>
-function, given a hue angle and chroma,
-finds the point of minimum lightness (L*) displayable by the screen.
-It returns this point in <acronym>CIE</acronym> L*u*v* coordinates.
-An
-<symbol>XcmsFailure</symbol>
-return value usually indicates that the given chroma
-is beyond maximum for the given hue angle.
-</para>
-</sect2>
-<sect2 id="TekHVC_Queries">
-<title>TekHVC Queries</title>
-<!-- .XS -->
-<!-- (SN TekHVC Queries -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To obtain the maximum Chroma for a given Hue and Value, use
-<function>XcmsTekHVCQueryMaxC</function>.
-</para>
-<indexterm><primary>Chroma</primary></indexterm>
-<indexterm><primary>Chroma</primary><secondary>maximum</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsTekHVCQueryMaxC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsTekHVCQueryMaxC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> value</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Hu in which to find the maximum Chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the Hue (Hu.
-<!-- .ds Va maximum Chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the Value in which to find the (Va.
-<!-- .ds Lc maximum Chroma along with the actual Hue and Value -->
-<!-- .ds lC maximum Chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the (Lc at which the (lC was found.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsTekHVCQueryMaxC</function>
-function, given a Hue and Value,
-determines the maximum Chroma in TekHVC color space
-displayable by the screen.
-It returns the maximum Chroma along with the actual Hue
-and Value at which the maximum Chroma was found.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the maximum Value for a given Hue and Chroma, use
-<function>XcmsTekHVCQueryMaxV</function>.
-</para>
-<indexterm><primary>Value</primary></indexterm>
-<indexterm><primary>Value</primary><secondary>maximum</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsTekHVCQueryMaxV</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsTekHVCQueryMaxV</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> chroma</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Hu in which to find the maximum Value -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the Hue (Hu.
-<!-- .ds Ch maximum Value -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>chroma</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the chroma at which to find (Ch.
-<!-- .ds Lc maximum Value along with the Hue and Chroma -->
-<!-- .ds lC maximum Value -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the (Lc at which the (lC was found.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsTekHVCQueryMaxV</function>
-function, given a Hue and Chroma,
-determines the maximum Value in TekHVC color space
-displayable by the screen.
-It returns the maximum Value and the actual Hue and Chroma
-at which the maximum Value was found.
-<!-- .sp -->
-</para>
-
-<para>
-<!-- .LP -->
-To obtain the maximum Chroma and Value at which it is reached
-for a specified Hue, use
-<function>XcmsTekHVCQueryMaxVC</function>.
-</para>
-<indexterm><primary>Chroma</primary></indexterm>
-<indexterm><primary>Value</primary></indexterm>
-<indexterm><primary>Chroma</primary><secondary>maximum</secondary></indexterm>
-<indexterm><primary>Value</primary><secondary>maximum</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsTekHVCQueryMaxVC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsTekHVCQueryMaxVC</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Hu in which to find the maximum Chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the Hue (Hu.
-<!-- .ds Lc color specification in \ -->
-XcmsTekHVC for the maximum Chroma, the Value at which \
-that maximum Chroma is reached, and the actual Hue
-<!-- .ds lC maximum Chroma -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the (Lc at which the (lC was found.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsTekHVCQueryMaxVC</function>
-function, given a Hue,
-determines the maximum Chroma in TekHVC color space displayable by the screen
-and the Value at which that maximum Chroma is reached.
-It returns the maximum Chroma,
-the Value at which that maximum Chroma is reached,
-and the actual Hue for which the maximum Chroma was found.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain a specified number of TekHVC specifications such that they
-contain maximum Values for a specified Hue and the
-Chroma at which the maximum Values are reached, use
-<function>XcmsTekHVCQueryMaxVSamples</function>.
-</para>
-<indexterm><primary>Chroma</primary></indexterm>
-<indexterm><primary>Value</primary></indexterm>
-<indexterm><primary>Chroma</primary><secondary>maximum</secondary></indexterm>
-<indexterm><primary>Value</primary><secondary>maximum</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsTekHVCQueryMaxVSamples</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsTekHVCQueryMaxVSamples</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue</parameter></paramdef>
- <paramdef>XcmsColor<parameter> colors_return[]</parameter></paramdef>
- <paramdef>unsignedint<parameter> nsamples</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Hu for maximum Chroma/Value samples -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the Hue (Hu.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nsamples</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of samples.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colors_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns nsamples of color specifications in XcmsTekHVC
-such that the Chroma is the maximum attainable for the Value and Hue.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsTekHVCQueryMaxVSamples</function>
-returns nsamples of maximum Value, the Chroma at which that maximum Value
-is reached, and the actual Hue for which the maximum Chroma was found.
-These sample points may then be used to plot the maximum Value/Chroma
-boundary of the screen's color gamut for the specified Hue in TekHVC color
-space.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the minimum Value for a given Hue and Chroma, use
-<function>XcmsTekHVCQueryMinV</function>.
-</para>
-<indexterm><primary>Value</primary></indexterm>
-<indexterm><primary>Value</primary><secondary>minimum</secondary></indexterm>
-<indexterm significance="preferred"><primary>XcmsTekHVCQueryMinV</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsTekHVCQueryMinV</function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> hue</parameter></paramdef>
- <paramdef>XcmsFloat<parameter> chroma</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
-The CCC's Client White Point and white point adjustment procedures
-are ignored.
-<!-- .ds Hu in which to find the minimum Value -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hue</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the Hue (Hu.
-<!-- .ds Va minimum Value -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the Value in which to find the (Va.
-<!-- .ds Lc minimum Value and the actual Hue and Chroma -->
-<!-- .ds lC minimum Value -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the (Lc at which the (lC was found.
-The white point associated with the returned
-color specification is the Screen White Point.
-The value returned in the pixel member is undefined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsTekHVCQueryMinV</function>
-function, given a Hue and Chroma,
-determines the minimum Value in TekHVC color space displayable by the screen.
-It returns the minimum Value and the actual Hue and Chroma at which
-the minimum Value was found.
-</para>
-
-</sect2>
-</sect1>
-<sect1 id="Color_Management_Extensions">
-<title>Color Management Extensions</title>
-<!-- .XS -->
-<!-- (SN Color Management Extensions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The Xlib color management facilities can be extended in two ways:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Device-Independent Color Spaces
- </para>
- </listitem>
- <listitem>
- <para>
-Device-independent color spaces that are derivable to <acronym>CIE</acronym> XYZ
-space can be added using the
-<function>XcmsAddColorSpace</function>
-function.
- </para>
- </listitem>
- <listitem>
- <para>
-Color Characterization Function Set
- </para>
- </listitem>
- <listitem>
- <para>
-A Color Characterization Function Set consists of
-device-dependent color spaces and their functions that
-convert between these color spaces and the <acronym>CIE</acronym> XYZ
-color space, bundled together for a specific class of output devices.
-A function set can be added using the
-<function>XcmsAddFunctionSet</function>
-function.
- </para>
- </listitem>
-</itemizedlist>
-<sect2 id="Color_Spaces">
-<title>Color Spaces</title>
-<!-- .XS -->
-<!-- (SN Color Spaces -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The <acronym>CIE</acronym> XYZ color space serves as the hub for all
-conversions between device-independent and device-dependent color spaces.
-Therefore, the knowledge to convert an
-<structname>XcmsColor</structname>
-structure to and from <acronym>CIE</acronym> XYZ format is associated with each color space.
-For example, conversion from <acronym>CIE</acronym> L*u*v* to <acronym>RGB</acronym> requires the knowledge
-to convert from <acronym>CIE</acronym> L*u*v* to <acronym>CIE</acronym> XYZ and from <acronym>CIE</acronym> XYZ to <acronym>RGB</acronym>.
-This knowledge is stored as an array of functions that,
-when applied in series, will convert the
-<structname>XcmsColor</structname>
-structure to or from <acronym>CIE</acronym> XYZ format.
-This color specification conversion mechanism facilitates
-the addition of color spaces.
-</para>
-<para>
-<!-- .LP -->
-Of course, when converting between only device-independent color spaces
-or only device-dependent color spaces,
-shortcuts are taken whenever possible.
-For example, conversion from TekHVC to <acronym>CIE</acronym> L*u*v* is performed
-by intermediate conversion to <acronym>CIE</acronym> u*v*Y and then to <acronym>CIE</acronym> L*u*v*,
-thus bypassing conversion between <acronym>CIE</acronym> u*v*Y and <acronym>CIE</acronym> XYZ.
-</para>
-</sect2>
-<sect2 id="Adding_Device_Independent_Color_Spaces">
-<title>Adding Device-Independent Color Spaces</title>
-<!-- .XS -->
-<!-- (SN Adding Device-Independent Color Spaces -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To add a device-independent color space, use
-<function>XcmsAddColorSpace</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsAddColorSpace</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsAddColorSpace</function></funcdef>
- <paramdef>XcmsColorSpace<parameter> *color_space</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_space</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the device-independent color space to add.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsAddColorSpace</function>
-function makes a device-independent color space (actually an
-<structname>XcmsColorSpace</structname>
-structure) accessible by the color management system.
-Because format values for unregistered color spaces are assigned at run time,
-they should be treated as private to the client.
-If references to an unregistered color space must be made
-outside the client (for example, storing color specifications
-in a file using the unregistered color space),
-then reference should be made by color space prefix
-(see
-<function>XcmsFormatOfPrefix</function>
-and
-<function>XcmsPrefixOfFormat</function>).
-</para>
-<para>
-<!-- .LP -->
-If the
-<structname>XcmsColorSpace</structname>
-structure is already accessible in the color management system,
-<function>XcmsAddColorSpace</function>
-returns
-<symbol>XcmsSuccess</symbol>.
-</para>
-<para>
-<!-- .LP -->
-Note that added
-<structname>XcmsColorSpace</structname>s
-must be retained for reference by Xlib.
-</para>
-</sect2>
-<sect2 id="Querying_Color_Space_Format_and_Prefix">
-<title>Querying Color Space Format and Prefix</title>
-<!-- .XS -->
-<!-- (SN Querying Color Space Format and Prefix -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To obtain the format associated with the color space
-associated with a specified color string prefix, use
-<function>XcmsFormatOfPrefix</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsFormatOfPrefix</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XcmsColorFormat <function>XcmsFormatOfPrefix</function></funcdef>
- <paramdef>char<parameter> *prefix</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>prefix</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the string that contains the color space prefix.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsFormatOfPrefix</function>
-function returns the format for the specified color space prefix
-(for example, the string ``CIEXYZ'').
-The prefix is case-insensitive.
-If the color space is not accessible in the color management system,
-<function>XcmsFormatOfPrefix</function>
-returns
-<symbol>XcmsUndefinedFormat</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the color string prefix associated with the color space
-specified by a color format, use
-<function>XcmsPrefixOfFormat</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsPrefixOfFormat</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XcmsPrefixOfFormat</function></funcdef>
- <paramdef>XcmsColorFormat<parameter> format</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color specification format.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsPrefixOfFormat</function>
-function returns the string prefix associated with the color specification
-encoding specified by the format argument.
-Otherwise, if no encoding is found, it returns NULL.
-The returned string must be treated as read-only.
-</para>
-</sect2>
-<sect2 id="Creating_Additional_Color_Spaces">
-<title>Creating Additional Color Spaces</title>
-<!-- .XS -->
-<!-- (SN Creating Additional Color Spaces -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Color space specific information necessary
-for color space conversion and color string parsing is stored in an
-<structname>XcmsColorSpace</structname>
-structure.
-Therefore, a new structure containing this information is required
-for each additional color space.
-In the case of device-independent color spaces,
-a handle to this new structure (that is, by means of a global variable)
-is usually made accessible to the client program for use with the
-<function>XcmsAddColorSpace</function>
-function.
-</para>
-<para>
-<!-- .LP -->
-If a new
-<structname>XcmsColorSpace</structname>
-structure specifies a color space not registered with the X Consortium,
-they should be treated as private to the client
-because format values for unregistered color spaces are assigned at run time.
-If references to an unregistered color space must be made outside the
-client (for example, storing color specifications in a file using the
-unregistered color space), then reference should be made by color space prefix
-(see
-<function>XcmsFormatOfPrefix</function>
-and
-<function>XcmsPrefixOfFormat</function>).
-<!-- .sM -->
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef (*XcmsConversionProc)();
-typedef XcmsConversionProc *XcmsFuncListPtr;
- /* A NULL terminated list of function pointers*/
-
-typedef struct _XcmsColorSpace {
- char *prefix;
- XcmsColorFormat format;
- XcmsParseStringProc parseString;
- XcmsFuncListPtr to_CIEXYZ;
- XcmsFuncListPtr from_CIEXYZ;
- int inverse_flag;
-} XcmsColorSpace;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The prefix member specifies the prefix that indicates a color string
-is in this color space's string format.
-For example, the strings ``ciexyz'' or ``CIEXYZ'' for <acronym>CIE</acronym> XYZ,
-and ``rgb'' or ``<acronym>RGB</acronym>'' for <acronym>RGB</acronym>.
-The prefix is case insensitive.
-The format member specifies the color specification format.
-Formats for unregistered color spaces are assigned at run time.
-The parseString member contains a pointer to the function
-that can parse a color string into an
-<structname>XcmsColor</structname>
-structure.
-This function returns an integer (int): nonzero if it succeeded
-and zero otherwise.
-The to_CIEXYZ and from_CIEXYZ members contain pointers,
-each to a NULL terminated list of function pointers.
-When the list of functions is executed in series,
-it will convert the color specified in an
-<structname>XcmsColor</structname>
-structure from/to the current color space format to/from the <acronym>CIE</acronym> XYZ format.
-Each function returns an integer (int): nonzero if it succeeded
-and zero otherwise.
-The white point to be associated with the colors is specified
-explicitly, even though white points can be found in the CCC.
-The inverse_flag member, if nonzero, specifies that for each function listed
-in to_CIEXYZ,
-its inverse function can be found in from_CIEXYZ such that:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-Given: n = number of functions in each list
-
-for each i, such that 0 &lt;= i &lt; n
- from_CIEXYZ[n - i - 1] is the inverse of to_CIEXYZ[i].
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-This allows Xlib to use the shortest conversion path,
-thus bypassing <acronym>CIE</acronym> XYZ if possible (for example, TekHVC to <acronym>CIE</acronym> L*u*v*).
-</para>
-</sect2>
-<sect2 id="Parse_String_Callback">
-<title>Parse String Callback</title>
-<!-- .XS -->
-<!-- (SN Parse String Callback -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The callback in the
-<structname>XcmsColorSpace</structname>
-structure for parsing a color string for the particular color space must
-adhere to the following software interface specification:
-</para>
-<indexterm significance="preferred"><primary>XcmsParseStringProc</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsParseStringProc</function></funcdef>
- <paramdef>char<parameter> *color_string</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the color string to parse.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>color_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the color specification in the color space's format.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-</para>
-</sect2>
-<sect2 id="Color_Specification_Conversion_Callback">
-<title>Color Specification Conversion Callback</title>
-<!-- .XS -->
-<!-- (SN Color Specification Conversion Callback -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Callback functions in the
-<structname>XcmsColorSpace</structname>
-structure for converting a color specification between device-independent
-spaces must adhere to the
-following software interface specification:
-</para>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function><replaceable>ConversionProc</replaceable></function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *white_point</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *colors_in_out</parameter></paramdef>
- <paramdef>unsignedint<parameter> ncolors</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>white_point</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the white point associated with color specifications.
-The pixel member should be ignored,
-and the entire structure remain unchanged upon return.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colors_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of color specifications.
-Pixel members should be ignored and must remain unchanged upon return.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ncolors</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of
-<structname>XcmsColor</structname>
-structures in the color-specification array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-Callback functions in the
-<structname>XcmsColorSpace</structname>
-structure for converting a color specification to or from a device-dependent
-space must adhere to the
-following software interface specification:
-</para>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function><replaceable>ConversionProc</replaceable></function></funcdef>
- <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
- <paramdef>XcmsColor<parameter> *colors_in_out</parameter></paramdef>
- <paramdef>unsignedint<parameter> ncolors</parameter></paramdef>
- <paramdef>Bool<parameter> compression_flags_return[]</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ccc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the CCC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colors_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of color specifications.
-Pixel members should be ignored and must remain unchanged upon return.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ncolors</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of
-<structname>XcmsColor</structname>
-structures in the color-specification array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>compression_flags_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns an array of Boolean values for indicating compression status.
-If a non-NULL pointer is supplied
-and a color at a given index is compressed, then
-<symbol>True</symbol>
-should be stored at the corresponding index in this array;
-otherwise, the array should not be modified.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Conversion functions are available globally for use by other color
-spaces.
-The conversion functions provided by Xlib are:
-</para>
-<informaltable>
- <tgroup cols='3' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <thead>
- <row>
- <entry>Function</entry>
- <entry>Converts from</entry>
- <entry>Converts to</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry><function>XcmsCIELabToCIEXYZ</function></entry>
- <entry><symbol>XcmsCIELabFormat</symbol></entry>
- <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsCIELuvToCIEuvY</function></entry>
- <entry><symbol>XcmsCIELuvFormat</symbol></entry>
- <entry><symbol>XcmsCIEuvYFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsCIEXYZToCIELab</function></entry>
- <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
- <entry><symbol>XcmsCIELabFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsCIEXYZToCIEuvY</function></entry>
- <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
- <entry><symbol>XcmsCIEuvYFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsCIEXYZToCIExyY</function></entry>
- <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
- <entry><symbol>XcmsCIExyYFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsCIEXYZToRGBi</function></entry>
- <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
- <entry><symbol>XcmsRGBiFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsCIEuvYToCIELuv</function></entry>
- <entry><symbol>XcmsCIEuvYFormat</symbol></entry>
- <entry><symbol>XcmsCIELabFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsCIEuvYToCIEXYZ</function></entry>
- <entry><symbol>XcmsCIEuvYFormat</symbol></entry>
- <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsCIEuvYToTekHVC</function></entry>
- <entry><symbol>XcmsCIEuvYFormat</symbol></entry>
- <entry><symbol>XcmsTekHVCFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsCIExyYToCIEXYZ</function></entry>
- <entry><symbol>XcmsCIExyYFormat</symbol></entry>
- <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsRGBToRGBi</function></entry>
- <entry><symbol>XcmsRGBFormat</symbol></entry>
- <entry><symbol>XcmsRGBiFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsRGBiToCIEXYZ</function></entry>
- <entry><symbol>XcmsRGBiFormat</symbol></entry>
- <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsRGBiToRGB</function></entry>
- <entry><symbol>XcmsRGBiFormat</symbol></entry>
- <entry><symbol>XcmsRGBFormat</symbol></entry>
- </row>
- <row>
- <entry><function>XcmsTekHVCToCIEuvY</function></entry>
- <entry><symbol>XcmsTekHVCFormat</symbol></entry>
- <entry><symbol>XcmsCIEuvYFormat</symbol></entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-</sect2>
-<sect2 id="Function_Sets">
-<title>Function Sets</title>
-<!-- .XS -->
-<!-- (SN Function Sets -->
-<!-- .XE -->
-<indexterm><primary>Function set</primary></indexterm>
-<indexterm><primary>Function set</primary><secondary>LINEAR_RGB</secondary></indexterm>
-<para>
-<!-- .LP -->
-Functions to convert between device-dependent color spaces
-and <acronym>CIE</acronym> XYZ may differ for different classes of output devices
-(for example, color versus gray monitors).
-Therefore, the notion of a Color Characterization Function Set
-has been developed.
-A function set consists of device-dependent color spaces
-and the functions that convert color specifications
-between these device-dependent color spaces and the <acronym>CIE</acronym> XYZ color space
-appropriate for a particular class of output devices.
-The function set also contains a function that reads
-color characterization data off root window properties.
-It is this characterization data that will differ between devices within
-a class of output devices.
-<indexterm><primary>Device Color Characterization</primary></indexterm>
-For details about how color characterization data is
-stored in root window properties,
-see the section on Device Color Characterization in the
-<emphasis remap='I'>Inter-Client Communication Conventions Manual</emphasis>.
-The LINEAR_RGB function set is provided by Xlib
-and will support most color monitors.
-Function sets may require data that differs
-from those needed for the LINEAR_RGB function set.
-In that case,
-its corresponding data may be stored on different root window properties.
-</para>
-</sect2>
-<sect2 id="Adding_Function_Sets">
-<title>Adding Function Sets</title>
-<!-- .XS -->
-<!-- (SN Adding Function Sets -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To add a function set, use
-<function>XcmsAddFunctionSet</function>.
-</para>
-<indexterm significance="preferred"><primary>XcmsAddFunctionSet</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XcmsAddFunctionSet</function></funcdef>
- <paramdef>XcmsFunctionSet<parameter> *function_set</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>function_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the function set to add.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XcmsAddFunctionSet</function>
-function adds a function set to the color management system.
-If the function set uses device-dependent
-<structname>XcmsColorSpace</structname>
-structures not accessible in the color management system,
-<function>XcmsAddFunctionSet</function>
-adds them.
-If an added
-<structname>XcmsColorSpace</structname>
-structure is for a device-dependent color space not registered
-with the X Consortium,
-they should be treated as private to the client
-because format values for unregistered color spaces are assigned at run time.
-If references to an unregistered color space must be made outside the
-client (for example, storing color specifications in a file
-using the unregistered color space),
-then reference should be made by color space prefix
-(see
-<function>XcmsFormatOfPrefix</function>
-and
-<function>XcmsPrefixOfFormat</function>).
-</para>
-<para>
-<!-- .LP -->
-Additional function sets should be added before any calls to other
-Xlib routines are made.
-If not, the
-<structname>XcmsPerScrnInfo</structname>
-member of a previously created
-<structname>XcmsCCC</structname>
-does not have the opportunity to initialize
-with the added function set.
-</para>
-</sect2>
-<sect2 id="Creating_Additional_Function_Sets">
-<title>Creating Additional Function Sets</title>
-<!-- .XS -->
-<!-- (SN Creating Additional Function Sets -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The creation of additional function sets should be
-required only when an output device does not conform to existing
-function sets or when additional device-dependent color spaces are necessary.
-A function set consists primarily of a collection of device-dependent
-<structname>XcmsColorSpace</structname>
-structures and a means to read and store a
-screen's color characterization data.
-This data is stored in an
-<structname>XcmsFunctionSet</structname>
-structure.
-A handle to this structure (that is, by means of global variable)
-is usually made accessible to the client program for use with
-<function>XcmsAddFunctionSet</function>.
-</para>
-<para>
-<!-- .LP -->
-If a function set uses new device-dependent
-<structname>XcmsColorSpace</structname>
-structures,
-they will be transparently processed into the color management system.
-Function sets can share an
-<structname>XcmsColorSpace</structname>
-structure for a device-dependent color space.
-In addition, multiple
-<structname>XcmsColorSpace</structname>
-structures are allowed for a device-dependent color space;
-however, a function set can reference only one of them.
-These
-<structname>XcmsColorSpace</structname>
-structures will differ in the functions to convert to and from <acronym>CIE</acronym> XYZ,
-thus tailored for the specific function set.
-<!-- .sM -->
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct _XcmsFunctionSet {
- XcmsColorSpace **DDColorSpaces;
- XcmsScreenInitProc screenInitProc;
- XcmsScreenFreeProc screenFreeProc;
-} XcmsFunctionSet;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The DDColorSpaces member is a pointer to a NULL terminated list
-of pointers to
-<structname>XcmsColorSpace</structname>
-structures for the device-dependent color spaces that are supported
-by the function set.
-The screenInitProc member is set to the callback procedure (see the following
-interface specification) that initializes the
-<structname>XcmsPerScrnInfo</structname>
-structure for a particular screen.
-</para>
-<para>
-<!-- .LP -->
-The screen initialization callback must adhere to the following software
-interface specification:
-<indexterm significance="preferred"><primary>XcmsScreenInitProc</primary></indexterm>
-<!-- .sM -->
-</para>
-<funcsynopsis>
-<funcprototype>
- <funcdef>typedef Status <function>(*XcmsScreenInitProc</function>)</funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> screen_number</parameter></paramdef>
- <paramdef>ScmsPerScrnInfo<parameter> *screen_info</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen_number</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the appropriate screen number on the host server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen_info</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XcmsPerScrnInfo</structname>
-structure, which contains the per screen information.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The screen initialization callback in the
-<structname>XcmsFunctionSet</structname>
-structure fetches the color characterization data (device profile) for
-the specified screen,
-typically off properties on the
-screen's root window.
-It then initializes the specified
-<structname>XcmsPerScrnInfo</structname>
-structure.
-<indexterm><primary>Device profile</primary></indexterm>
-<indexterm><primary>Color Characterization Data</primary></indexterm>
-If successful, the procedure fills in the
-<structname>XcmsPerScrnInfo</structname>
-structure as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-It sets the screenData member to the address
-of the created device profile data structure
-(contents known only by the function set).
- </para>
- </listitem>
- <listitem>
- <para>
-It next sets the screenWhitePoint member.
- </para>
- </listitem>
- <listitem>
- <para>
-It next sets the functionSet member to the address of the
-<structname>XcmsFunctionSet</structname>
-structure.
- </para>
- </listitem>
- <listitem>
- <para>
-It then sets the state member to
-<symbol>XcmsInitSuccess</symbol>
-and finally returns
-<symbol>XcmsSuccess</symbol>.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-If unsuccessful, the procedure sets the state member to
-<symbol>XcmsInitFailure</symbol>
-and returns
-<symbol>XcmsFailure</symbol>.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XcmsPerScrnInfo</structname>
-structure contains:
-<!-- .sM -->
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct _XcmsPerScrnInfo {
- XcmsColor screenWhitePoint;
- XPointer functionSet;
- XPointer screenData;
- unsigned char state;
- char pad[3];
-} XcmsPerScrnInfo;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The screenWhitePoint member specifies the white point inherent to
-the screen.
-The functionSet member specifies the appropriate function set.
-The screenData member specifies the device profile.
-The state member is set to one of the following:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-<symbol>XcmsInitNone</symbol>
-indicates initialization has not been previously attempted.
- </para>
- </listitem>
- <listitem>
- <para>
-<symbol>XcmsInitFailure</symbol>
-indicates initialization has been previously attempted but failed.
- </para>
- </listitem>
- <listitem>
- <para>
-<symbol>XcmsInitSuccess</symbol>
-indicates initialization has been previously attempted and succeeded.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The screen free callback must adhere to the following software
-interface specification:
-</para>
-<funcsynopsis>
-<funcprototype>
- <funcdef>typedef void (*XcmsScreenFreeProc)</funcdef>
- <paramdef>XPointer<parameter> screenData</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>screenData</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the data to be freed.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-This function is called to free the screenData stored in an
-<structname>XcmsPerScrnInfo</structname>
-structure.
-<!-- .bp -->
-
-</para>
-</sect2>
-</sect1>
-</chapter>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<chapter id="color_management_functions">
+<title>Color Management Functions</title>
+<!-- .sp 2 -->
+<!-- .nr H1 6 -->
+<!-- .nr H2 0 -->
+<!-- .nr H3 0 -->
+<!-- .nr H4 0 -->
+<!-- .nr H5 0 -->
+<!-- .na -->
+<para>
+<!-- .LP -->
+<!-- .XS -->
+<!-- Chapter 6: Color Management Functions -->
+<!-- .XE -->
+Each X window always has an associated colormap that
+provides a level of indirection between pixel values and colors displayed
+on the screen.
+Xlib provides functions that you can use to manipulate a colormap.
+The X protocol defines colors using values in the <acronym>RGB</acronym> color space.
+The <acronym>RGB</acronym> color space is device dependent;
+rendering an <acronym>RGB</acronym> value on differing output devices typically results
+in different colors.
+Xlib also provides a means for clients to specify color using
+device-independent color spaces for consistent results across devices.
+Xlib supports device-independent color spaces derivable from the <acronym>CIE</acronym> XYZ
+color space.
+This includes the <acronym>CIE</acronym> XYZ, xyY, L*u*v*, and L*a*b* color spaces as well as
+the TekHVC color space.
+</para>
+<para>
+<!-- .LP -->
+This chapter discusses how to:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Create, copy, and destroy a colormap
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Specify colors by name or value
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Allocate, modify, and free color cells
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Read entries in a colormap
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Convert between color spaces
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Control aspects of color conversion
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Query the color gamut of a screen
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Add new color spaces
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+All functions, types, and symbols in this chapter with the prefix ``Xcms''
+are defined in
+<filename class="headerfile">&lt;X11/Xcms.h&gt;</filename>.
+<indexterm type="file"><primary><filename class="headerfile">X11/Xcms.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xcms.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xcms.h&gt;</filename></secondary></indexterm>
+The remaining functions and types are defined in
+<filename class="headerfile">&lt;X11/Xlib.h&gt;</filename>.
+<indexterm type="file"><primary><filename class="headerfile">X11/Xlib.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xlib.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xlib.h&gt;</filename></secondary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+Functions in this chapter manipulate the representation of color on the
+screen.
+For each possible value that a pixel can take in a window,
+there is a color cell in the colormap.
+For example,
+if a window is 4 bits deep, pixel values 0 through 15 are defined.
+A colormap is a collection of color cells.
+A color cell consists of a triple of red, green, and blue (<acronym>RGB</acronym>) values.
+The hardware imposes limits on the number of significant
+bits in these values.
+As each pixel is read out of display memory, the pixel
+is looked up in a colormap.
+The <acronym>RGB</acronym> value of the cell determines what color is displayed on the screen.
+On a grayscale display with a black-and-white monitor,
+the values are combined to determine the brightness on the screen.
+</para>
+<para>
+<!-- .LP -->
+Typically, an application allocates color cells or sets of color cells
+to obtain the desired colors.
+The client can allocate read-only cells.
+In which case,
+the pixel values for these colors can be shared among multiple applications,
+and the <acronym>RGB</acronym> value of the cell cannot be changed.
+If the client allocates read/write cells,
+they are exclusively owned by the client,
+and the color associated with the pixel value can be changed at will.
+Cells must be allocated (and, if read/write, initialized with an <acronym>RGB</acronym> value)
+by a client to obtain desired colors.
+The use of pixel value for an
+unallocated cell results in an undefined color.
+</para>
+<para>
+<!-- .LP -->
+Because colormaps are associated with windows, X supports displays
+with multiple colormaps and, indeed, different types of colormaps.
+If there are insufficient colormap resources in the display,
+some windows will display in their true colors, and others
+will display with incorrect colors.
+A window manager usually controls which windows are displayed
+in their true colors if more than one colormap is required for
+the color resources the applications are using.
+At any time, there is a set of installed colormaps for a screen.
+Windows using one of the installed colormaps display with true colors, and
+windows using other colormaps generally display with incorrect colors.
+You can control the set of installed colormaps by using
+<function>XInstallColormap</function>
+and
+<function>XUninstallColormap</function>.
+</para>
+<para>
+<!-- .LP -->
+Colormaps are local to a particular screen.
+Screens always have a default colormap,
+and programs typically allocate cells out of this colormap.
+Generally, you should not write applications that monopolize
+color resources.
+Although some hardware supports multiple colormaps installed at one time,
+many of the hardware displays
+built today support only a single installed colormap, so the primitives
+are written to encourage sharing of colormap entries between applications.
+</para>
+<para>
+<!-- .LP -->
+The
+<function>DefaultColormap</function>
+macro returns the default colormap.
+The
+<function>DefaultVisual</function>
+macro
+returns the default visual type for the specified screen.
+<indexterm><primary>Color map</primary></indexterm>
+Possible visual types are
+<symbol>StaticGray</symbol>,
+<symbol>GrayScale</symbol>,
+<symbol>StaticColor</symbol>,
+<symbol>PseudoColor</symbol>,
+<symbol>TrueColor</symbol>,
+or
+<symbol>DirectColor</symbol>
+(see section 3.1).
+</para>
+<sect1 id="Color_Structures">
+<title>Color Structures</title>
+<!-- .XS -->
+<!-- (SN Color Structures -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Functions that operate only on <acronym>RGB</acronym> color space values use an
+<structname>XColor</structname>
+structure, which contains:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XColor</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ unsigned long pixel; /* pixel value */
+ unsigned short red, green, blue; /* rgb values */
+ char flags; /* DoRed, DoGreen, DoBlue */
+ char pad;
+} XColor;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The red, green, and blue values are always in the range 0 to 65535
+inclusive, independent of the number of bits actually used in the
+display hardware.
+The server scales these values down to the range used by the hardware.
+Black is represented by (0,0,0),
+and white is represented by (65535,65535,65535).
+<indexterm><primary>Color</primary></indexterm>
+In some functions,
+the flags member controls which of the red, green, and blue members is used
+and can be the inclusive OR of zero or more of
+<symbol>DoRed</symbol>,
+<symbol>DoGreen</symbol>,
+and
+<symbol>DoBlue</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+Functions that operate on all color space values use an
+<structname>XcmsColor</structname>
+structure.
+This structure contains a union of substructures,
+each supporting color specification encoding for a particular color space.
+Like the
+<structname>XColor</structname>
+structure, the
+<structname>XcmsColor</structname>
+structure contains pixel
+and color specification information (the spec member in the
+<structname>XcmsColor</structname>
+structure).
+<indexterm significance="preferred"><primary>XcmsColor</primary></indexterm>
+<!-- .sM -->
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 1i 2.5i -->
+<!-- .ta .5i 1i 2.5i -->
+typedef unsigned long XcmsColorFormat; /* Color Specification Format */
+
+typedef struct {
+ union {
+ XcmsRGB RGB;
+ XcmsRGBi RGBi;
+ XcmsCIEXYZ CIEXYZ;
+ XcmsCIEuvY CIEuvY;
+ XcmsCIExyY CIExyY;
+ XcmsCIELab CIELab;
+ XcmsCIELuv CIELuv;
+ XcmsTekHVC TekHVC;
+ XcmsPad Pad;
+ } spec;
+ unsigned long pixel;
+ XcmsColorFormat format;
+} XcmsColor; /* Xcms Color Structure */
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Because the color specification can be encoded for the various color spaces,
+encoding for the spec member is identified by the format member,
+which is of type
+<type>XcmsColorFormat</type>.
+The following macros define standard formats.
+<!-- .sM -->
+</para>
+
+<literallayout class="monospaced">
+#define XcmsUndefinedFormat 0x00000000
+#define XcmsCIEXYZFormat 0x00000001 /* CIE XYZ */
+#define XcmsCIEuvYFormat 0x00000002 /* CIE u'v'Y */
+#define XcmsCIExyYFormat 0x00000003 /* CIE xyY */
+#define XcmsCIELabFormat 0x00000004 /* CIE L*a*b* */
+#define XcmsCIELuvFormat 0x00000005 /* CIE L*u*v* */
+#define XcmsTekHVCFormat 0x00000006 /* TekHVC */
+#define XcmsRGBFormat 0x80000000 /* RGB Device */
+#define XcmsRGBiFormat 0x80000001 /* RGB Intensity */
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Formats for device-independent color spaces are
+distinguishable from those for device-dependent spaces by the 32nd bit.
+If this bit is set,
+it indicates that the color specification is in a device-dependent form;
+otherwise, it is in a device-independent form.
+If the 31st bit is set,
+this indicates that the color space has been added to Xlib at run time
+(see section 6.12.4).
+The format value for a color space added at run time may be different each
+time the program is executed.
+If references to such a color space must be made outside the client
+(for example, storing a color specification in a file),
+then reference should be made by color space string prefix
+(see
+<function>XcmsFormatOfPrefix</function>
+and
+<function>XcmsPrefixOfFormat</function>).
+</para>
+<para>
+<!-- .LP -->
+Data types that describe the color specification encoding for the various
+color spaces are defined as follows:
+<!-- .sM -->
+<indexterm significance="preferred"><primary>XcmsRGB</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef double XcmsFloat;
+
+typedef struct {
+ unsigned short red; /* 0x0000 to 0xffff */
+ unsigned short green; /* 0x0000 to 0xffff */
+ unsigned short blue; /* 0x0000 to 0xffff */
+} XcmsRGB; /* RGB Device */
+</literallayout>
+<indexterm significance="preferred"><primary>XcmsRGBi</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ XcmsFloat red; /* 0.0 to 1.0 */
+ XcmsFloat green; /* 0.0 to 1.0 */
+ XcmsFloat blue; /* 0.0 to 1.0 */
+} XcmsRGBi; /* RGB Intensity */
+</literallayout>
+<indexterm significance="preferred"><primary>XcmsCIEXYZ</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ XcmsFloat X;
+ XcmsFloat Y; /* 0.0 to 1.0 */
+ XcmsFloat Z;
+} XcmsCIEXYZ; /* CIE XYZ */
+</literallayout>
+<indexterm significance="preferred"><primary>XcmsCIEuvY</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ XcmsFloat u_prime; /* 0.0 to ~0.6 */
+ XcmsFloat v_prime; /* 0.0 to ~0.6 */
+ XcmsFloat Y; /* 0.0 to 1.0 */
+} XcmsCIEuvY; /* CIE u'v'Y */
+</literallayout>
+<indexterm significance="preferred"><primary>XcmsCIExyY</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ XcmsFloat x; /* 0.0 to ~.75 */
+ XcmsFloat y; /* 0.0 to ~.85 */
+ XcmsFloat Y; /* 0.0 to 1.0 */
+} XcmsCIExyY; /* CIE xyY */
+</literallayout>
+<indexterm significance="preferred"><primary>XcmsCIELab</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ XcmsFloat L_star; /* 0.0 to 100.0 */
+ XcmsFloat a_star;
+ XcmsFloat b_star;
+} XcmsCIELab; /* CIE L*a*b* */
+</literallayout>
+<indexterm significance="preferred"><primary>XcmsCIELuv</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ XcmsFloat L_star; /* 0.0 to 100.0 */
+ XcmsFloat u_star;
+ XcmsFloat v_star;
+} XcmsCIELuv; /* CIE L*u*v* */
+</literallayout>
+<indexterm significance="preferred"><primary>XcmsTekHVC</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ XcmsFloat H; /* 0.0 to 360.0 */
+ XcmsFloat V; /* 0.0 to 100.0 */
+ XcmsFloat C; /* 0.0 to 100.0 */
+} XcmsTekHVC; /* TekHVC */
+</literallayout>
+<indexterm significance="preferred"><primary>XcmsPad</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ XcmsFloat pad0;
+ XcmsFloat pad1;
+ XcmsFloat pad2;
+ XcmsFloat pad3;
+} XcmsPad; /* four doubles */
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The device-dependent formats provided allow color specification in:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+<acronym>RGB</acronym> Intensity
+(<structname>XcmsRGBi</structname>)
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Red, green, and blue linear intensity values,
+floating-point values from 0.0 to 1.0,
+where 1.0 indicates full intensity, 0.5 half intensity, and so on.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<acronym>RGB</acronym> Device
+(<structname>XcmsRGB</structname>)
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Red, green, and blue values appropriate for the specified output device.
+<structname>XcmsRGB</structname>
+values are of type unsigned short,
+scaled from 0 to 65535 inclusive,
+and are interchangeable with the red, green, and blue values in an
+<structname>XColor</structname>
+structure.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+It is important to note that <acronym>RGB</acronym> Intensity values are not gamma corrected
+values.
+In contrast,
+<acronym>RGB</acronym> Device values generated as a result of converting color specifications
+are always gamma corrected, and
+<acronym>RGB</acronym> Device values acquired as a result of querying a colormap
+or passed in by the client are assumed by Xlib to be gamma corrected.
+The term <emphasis remap='I'><acronym>RGB</acronym> value</emphasis> in this manual always refers to an <acronym>RGB</acronym> Device value.
+</para>
+</sect1>
+<sect1 id="Color_Strings">
+<title>Color Strings</title>
+<!-- .XS -->
+<!-- (SN Color Strings -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides a mechanism for using string names for colors.
+A color string may either contain an abstract color name
+or a numerical color specification.
+Color strings are case-insensitive.
+</para>
+<para>
+<!-- .LP -->
+Color strings are used in the following functions:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+<function>XAllocNamedColor</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XcmsAllocNamedColor</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XLookupColor</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XcmsLookupColor</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XParseColor</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XStoreNamedColor</function>
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Xlib supports the use of abstract color names, for example, red or blue.
+A value for this abstract name is obtained by searching one or more color
+name databases.
+Xlib first searches zero or more client-side databases;
+the number, location, and content of these databases is
+implementation-dependent and might depend on the current locale.
+If the name is not found, Xlib then looks for the color in the
+X server's database.
+If the color name is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+A numerical color specification
+consists of a color space name and a set of values in the following syntax:
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<literallayout class="monospaced">
+<emphasis remap='I'>&lt;color_space_name&gt;</emphasis>:<emphasis remap='I'>&lt;value&gt;/.../&lt;value&gt;</emphasis>
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The following are examples of valid color strings.
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+"CIEXYZ:0.3227/0.28133/0.2493"
+"RGBi:1.0/0.0/0.0"
+"rgb:00/ff/00"
+"CIELuv:50.0/0.0/0.0"
+</literallayout>
+The syntax and semantics of numerical specifications are given
+for each standard color space in the following sections.
+</para>
+<sect2 id="RGB_Device_String_Specification">
+<title><acronym>RGB</acronym> Device String Specification</title>
+<!-- .XS -->
+<!-- (SN <acronym>RGB</acronym> Device String Specification -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+An <acronym>RGB</acronym> Device specification is identified by
+the prefix ``rgb:'' and conforms to the following syntax:
+</para>
+<para>
+<!-- .LP -->
+<!-- .\" Start marker code here -->
+<literallayout class="monospaced">
+rgb:<emphasis remap='I'>&lt;red&gt;/&lt;green&gt;/&lt;blue&gt;</emphasis>
+
+ <emphasis remap='I'>&lt;red&gt;</emphasis>, <emphasis remap='I'>&lt;green&gt;</emphasis>, <emphasis remap='I'>&lt;blue&gt;</emphasis> := <emphasis remap='I'>h</emphasis> | <emphasis remap='I'>hh</emphasis> | <emphasis remap='I'>hhh</emphasis> | <emphasis remap='I'>hhhh</emphasis>
+ <emphasis remap='I'>h</emphasis> := single hexadecimal digits (case insignificant)
+</literallayout>
+<!-- .\" End marker code here -->
+</para>
+<para>
+<!-- .LP -->
+Note that <emphasis remap='I'>h</emphasis> indicates the value scaled in 4 bits,
+<emphasis remap='I'>hh</emphasis> the value scaled in 8 bits,
+<emphasis remap='I'>hhh</emphasis> the value scaled in 12 bits,
+and <emphasis remap='I'>hhhh</emphasis> the value scaled in 16 bits, respectively.
+</para>
+<para>
+<!-- .LP -->
+Typical examples are the strings ``rgb:ea/75/52'' and ``rgb:ccc/320/320'',
+but mixed numbers of hexadecimal digit strings
+(``rgb:ff/a5/0'' and ``rgb:ccc/32/0'')
+are also allowed.
+</para>
+<para>
+<!-- .LP -->
+For backward compatibility, an older syntax for <acronym>RGB</acronym> Device is
+supported, but its continued use is not encouraged.
+The syntax is an initial sharp sign character followed by
+a numeric specification, in one of the following formats:
+</para>
+<para>
+<!-- .LP -->
+<!-- .\" Start marker code here -->
+<literallayout class="monospaced">
+<!-- .TA 2i -->
+<!-- .ta 2i -->
+#RGB (4 bits each)
+#RRGGBB (8 bits each)
+#RRRGGGBBB (12 bits each)
+#RRRRGGGGBBBB (16 bits each)
+</literallayout>
+<!-- .\" End marker code here -->
+</para>
+<para>
+<!-- .LP -->
+The R, G, and B represent single hexadecimal digits.
+When fewer than 16 bits each are specified,
+they represent the most significant bits of the value
+(unlike the ``rgb:'' syntax, in which values are scaled).
+For example, the string ``#3a7'' is the same as ``#3000a0007000''.
+</para>
+</sect2>
+<sect2 id="RGB_Intensity_String_Specification">
+<title><acronym>RGB</acronym> Intensity String Specification</title>
+<!-- .XS -->
+<!-- (SN RGB Intensity String Specification -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+An <acronym>RGB</acronym> intensity specification is identified
+by the prefix ``rgbi:'' and conforms to the following syntax:
+</para>
+<para>
+<!-- .LP -->
+<!-- .\" Start marker code here -->
+<literallayout class="monospaced">
+rgbi:<emphasis remap='I'>&lt;red&gt;/&lt;green&gt;/&lt;blue&gt;</emphasis>
+</literallayout>
+<!-- .\" End marker code here -->
+</para>
+<para>
+<!-- .LP -->
+Note that red, green, and blue are floating-point values
+between 0.0 and 1.0, inclusive.
+The input format for these values is an optional sign,
+a string of numbers possibly containing a decimal point,
+and an optional exponent field containing an E or e
+followed by a possibly signed integer string.
+</para>
+</sect2>
+<sect2 id="Device_Independent_String_Specifications">
+<title>Device-Independent String Specifications</title>
+<!-- .XS -->
+<!-- (SN Device-Independent String Specifications -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The standard device-independent string specifications have
+the following syntax:
+</para>
+<para>
+<!-- .LP -->
+<!-- .\" Start marker code here -->
+<literallayout class="monospaced">
+CIEXYZ:<emphasis remap='I'>&lt;X&gt;/&lt;Y&gt;/&lt;Z&gt;</emphasis>
+CIEuvY:<emphasis remap='I'>&lt;u&gt;/&lt;v&gt;/&lt;Y&gt;</emphasis>
+CIExyY:<emphasis remap='I'>&lt;x&gt;/&lt;y&gt;/&lt;Y&gt;</emphasis>
+CIELab:<emphasis remap='I'>&lt;L&gt;/&lt;a&gt;/&lt;b&gt;</emphasis>
+CIELuv:<emphasis remap='I'>&lt;L&gt;/&lt;u&gt;/&lt;v&gt;</emphasis>
+TekHVC:<emphasis remap='I'>&lt;H&gt;/&lt;V&gt;/&lt;C&gt;</emphasis>
+</literallayout>
+<!-- .\" End marker code here -->
+</para>
+<para>
+<!-- .LP -->
+All of the values (C, H, V, X, Y, Z, a, b, u, v, y, x) are
+floating-point values.
+The syntax for these values is an optional plus or minus sign,
+a string of digits possibly containing a decimal point,
+and an optional exponent field consisting of an ``E'' or ``e''
+followed by an optional plus or minus followed by a string of digits.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Color_Conversion_Contexts_and_Gamut_Mapping">
+<title>Color Conversion Contexts and Gamut Mapping</title>
+<!-- .XS -->
+<!-- (SN Color Conversion Contexts and Gamut Mapping -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+When Xlib converts device-independent color specifications
+into device-dependent specifications and vice versa,
+it uses knowledge about the color limitations of the screen hardware.
+This information, typically called the device profile,
+<indexterm><primary>Device profile</primary></indexterm>
+is available in a Color Conversion Context (CCC).
+<indexterm><primary>Color Conversion Context</primary></indexterm>
+<indexterm><primary>CCC</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+Because a specified color may be outside the color gamut of the target screen
+and the white point associated with the color specification may differ
+from the white point inherent to the screen,
+Xlib applies gamut mapping when it encounters certain conditions:
+<indexterm><primary>White point</primary></indexterm>
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Gamut compression occurs when conversion of device-independent
+color specifications to device-dependent color specifications
+results in a color out of the target screen's gamut.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+White adjustment occurs when the inherent white point of the screen
+differs from the white point assumed by the client.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Gamut handling methods are stored as callbacks in the CCC,
+which in turn are used by the color space conversion routines.
+Client data is also stored in the CCC for each callback.
+The CCC also contains the white point the client assumes to be
+associated with color specifications (that is, the Client White Point).
+<indexterm><primary>Client White Point</primary></indexterm>
+<indexterm><primary>Gamut compression</primary></indexterm>
+<indexterm><primary>Gamut handling</primary></indexterm>
+<indexterm><primary>White point adjustment</primary></indexterm>
+The client can specify the gamut handling callbacks and client data
+as well as the Client White Point.
+Xlib does not preclude the X client from performing other
+forms of gamut handling (for example, gamut expansion);
+however, Xlib does not provide direct support for gamut handling
+other than white adjustment and gamut compression.
+</para>
+<para>
+<!-- .LP -->
+Associated with each colormap is an initial CCC transparently generated by
+Xlib.
+<indexterm><primary>Color Conversion Context</primary><secondary>creation</secondary></indexterm>
+Therefore,
+when you specify a colormap as an argument to an Xlib function,
+you are indirectly specifying a CCC.
+<indexterm><primary>CCC</primary><secondary>of colormap</secondary></indexterm>
+<indexterm><primary>Color Conversion Context</primary><secondary>of colormap</secondary></indexterm>
+There is a default CCC associated with each screen.
+Newly created CCCs inherit attributes from the default CCC,
+so the default CCC attributes can be modified to affect new CCCs.
+<indexterm><primary>CCC</primary><secondary>default</secondary></indexterm>
+<indexterm><primary>Color Conversion Context</primary><secondary>default</secondary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+Xcms functions in which gamut mapping can occur return
+<type>Status</type>
+and have specific status values defined for them,
+as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+<symbol>XcmsFailure</symbol>
+indicates that the function failed.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<symbol>XcmsSuccess</symbol>
+indicates that the function succeeded.
+In addition,
+if the function performed any color conversion,
+the colors did not need to be compressed.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<symbol>XcmsSuccessWithCompression</symbol>
+indicates the function performed color conversion
+and at least one of the colors needed to be compressed.
+The gamut compression method is determined by the gamut compression
+procedure in the CCC that is specified directly as a function argument
+or in the CCC indirectly specified by means of the colormap argument.
+ </para>
+ </listitem>
+</itemizedlist>
+</sect1>
+<sect1 id="Creating_Copying_and_Destroying_Colormaps">
+<title>Creating, Copying, and Destroying Colormaps</title>
+<!-- .XS -->
+<!-- (SN Creating, Copying, and Destroying Colormaps -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To create a colormap for a screen, use
+<function>XCreateColormap</function>.</para>
+<indexterm significance="preferred"><primary>XCreateColormap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreatecolormap'>
+<funcprototype>
+ <funcdef>Colormap <function>XCreateColormap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Visual<parameter> *visual</parameter></paramdef>
+ <paramdef>int<parameter> alloc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Wi on whose screen you want to create a colormap -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window (Wi.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>visual</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a visual type supported on the screen.
+If the visual type is not one supported by the screen,
+a
+<errorname>BadMatch</errorname>
+error results.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>alloc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap entries to be allocated.
+You can pass
+<symbol>AllocNone</symbol>
+or
+<symbol>AllocAll</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreateColormap</function>
+function creates a colormap of the specified visual type for the screen
+on which the specified window resides and returns the colormap ID
+associated with it.
+Note that the specified window is only used to determine the screen.
+</para>
+<para>
+<!-- .LP -->
+The initial values of the colormap entries are undefined for the
+visual classes
+<symbol>GrayScale</symbol>,
+<symbol>PseudoColor</symbol>,
+and
+<symbol>DirectColor</symbol>.
+For
+<symbol>StaticGray</symbol>,
+<symbol>StaticColor</symbol>,
+and
+<symbol>TrueColor</symbol>,
+the entries have defined values,
+but those values are specific to the visual and are not defined by X.
+For
+<symbol>StaticGray</symbol>,
+<symbol>StaticColor</symbol>,
+and
+<symbol>TrueColor</symbol>,
+alloc must be
+<symbol>AllocNone</symbol>,
+or a
+<errorname>BadMatch</errorname>
+error results.
+For the other visual classes,
+if alloc is
+<symbol>AllocNone</symbol>,
+the colormap initially has no allocated entries,
+and clients can allocate them.
+For information about the visual types,
+see section 3.1.
+</para>
+<para>
+<!-- .LP -->
+If alloc is
+<symbol>AllocAll</symbol>,
+the entire colormap is allocated writable.
+The initial values of all allocated entries are undefined.
+For
+<symbol>GrayScale</symbol>
+and
+<symbol>PseudoColor</symbol>,
+the effect is as if an
+<function>XAllocColorCells</function>
+call returned all pixel values from zero to N - 1,
+where N is the colormap entries value in the specified visual.
+For
+<symbol>DirectColor</symbol>,
+the effect is as if an
+<function>XAllocColorPlanes</function>
+call returned a pixel value of zero and red_mask, green_mask,
+and blue_mask values containing the same bits as the corresponding
+masks in the specified visual.
+However, in all cases,
+none of these entries can be freed by using
+<function>XFreeColors</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreateColormap</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadMatch</errorname>,
+<errorname>BadValue</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create a new colormap when the allocation out of a previously
+shared colormap has failed because of resource exhaustion, use
+<function>XCopyColormapAndFree</function>.
+<indexterm significance="preferred"><primary>XCopyColormapAndFree</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcopycolormapandfree'>
+<funcprototype>
+ <funcdef>Colormap <function>XCopyColormapAndFree</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCopyColormapAndFree</function>
+function creates a colormap of the same visual type and for the same screen
+as the specified colormap and returns the new colormap ID.
+It also moves all of the client's existing allocation from the specified
+colormap to the new colormap with their color values intact
+and their read-only or writable characteristics intact and frees those entries
+in the specified colormap.
+Color values in other entries in the new colormap are undefined.
+If the specified colormap was created by the client with alloc set to
+<symbol>AllocAll</symbol>,
+the new colormap is also created with
+<symbol>AllocAll</symbol>,
+all color values for all entries are copied from the specified colormap,
+and then all entries in the specified colormap are freed.
+If the specified colormap was not created by the client with
+<symbol>AllocAll</symbol>,
+the allocations to be moved are all those pixels and planes
+that have been allocated by the client using
+<function>XAllocColor</function>,
+<function>XAllocNamedColor</function>,
+<function>XAllocColorCells</function>,
+or
+<function>XAllocColorPlanes</function>
+and that have not been freed since they were allocated.
+</para>
+<para>
+<!-- .LP -->
+<function>XCopyColormapAndFree</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadColor</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To destroy a colormap, use
+<function>XFreeColormap</function>.
+<indexterm significance="preferred"><primary>XFreeColormap</primary></indexterm>
+</para>
+<!-- .sM -->
+<funcsynopsis id='xfreecolormap'>
+<funcprototype>
+ <funcdef><function>XFreeColormap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Cm that you want to destroy -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap (Cm.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreeColormap</function>
+function deletes the association between the colormap resource ID
+and the colormap and frees the colormap storage.
+However, this function has no effect on the default colormap for a screen.
+If the specified colormap is an installed map for a screen,
+it is uninstalled (see
+<function>XUninstallColormap</function>).
+If the specified colormap is defined as the colormap for a window (by
+<function>XCreateWindow</function>,
+<function>XSetWindowColormap</function>,
+or
+<function>XChangeWindowAttributes</function>),
+<function>XFreeColormap</function>
+changes the colormap associated with the window to
+<symbol>None</symbol>
+and generates a
+<symbol>ColormapNotify</symbol>
+event.
+X does not define the colors displayed for a window with a colormap of
+<symbol>None</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<function>XFreeColormap</function>
+can generate a
+<errorname>BadColor</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Mapping_Color_Names_to_Values">
+<title>Mapping Color Names to Values</title>
+<!-- .XS -->
+<!-- (SN Mapping Color Names to Values -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To map a color name to an <acronym>RGB</acronym> value, use
+<function>XLookupColor</function>.
+<indexterm><primary>Color</primary><secondary>naming</secondary></indexterm>
+<indexterm significance="preferred"><primary>XLookupColor</primary></indexterm>
+<!-- .sM -->
+</para>
+<funcsynopsis id='xlookupcolor'>
+<funcprototype>
+ <funcdef>Status <function>XLookupColor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>char<parameter> *color_name</parameter></paramdef>
+ <paramdef>XColor*exact_def_return,<parameter> *screen_def_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color name string (for example, red) whose color
+definition structure you want returned.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>exact_def_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the exact <acronym>RGB</acronym> values.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen_def_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the closest <acronym>RGB</acronym> values provided by the hardware.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XLookupColor</function>
+function looks up the string name of a color with respect to the screen
+associated with the specified colormap.
+It returns both the exact color values and
+the closest values provided by the screen
+with respect to the visual type of the specified colormap.
+If the color name is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+Use of uppercase or lowercase does not matter.
+<function>XLookupColor</function>
+returns nonzero if the name is resolved;
+otherwise, it returns zero.
+</para>
+<para>
+<!-- .LP -->
+<function>XLookupColor</function>
+can generate a
+<errorname>BadColor</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To map a color name to the exact <acronym>RGB</acronym> value, use
+<function>XParseColor</function>.
+</para>
+<indexterm><primary>Color</primary><secondary>naming</secondary></indexterm>
+<indexterm significance="preferred"><primary>XParseColor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xparsecolor'>
+<funcprototype>
+ <funcdef>Status <function>XParseColor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>char<parameter> *spec</parameter></paramdef>
+ <paramdef>XColor<parameter> *exact_def_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>spec</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color name string;
+case is ignored.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>exact_def_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the exact color value for later use and sets the
+<symbol>DoRed</symbol>,
+<symbol>DoGreen</symbol>,
+and
+<symbol>DoBlue</symbol>
+flags.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XParseColor</function>
+function looks up the string name of a color with respect to the screen
+associated with the specified colormap.
+It returns the exact color value.
+If the color name is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+Use of uppercase or lowercase does not matter.
+<function>XParseColor</function>
+returns nonzero if the name is resolved;
+otherwise, it returns zero.
+</para>
+<para>
+<!-- .LP -->
+<function>XParseColor</function>
+can generate a
+<errorname>BadColor</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To map a color name to a value in an arbitrary color space, use
+<function>XcmsLookupColor</function>.
+</para>
+<indexterm><primary>Color</primary><secondary>naming</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsLookupColor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmslookupcolor'>
+<funcprototype>
+ <funcdef>Status <function>XcmsLookupColor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>char<parameter> *color_string</parameter></paramdef>
+ <paramdef>XcmsColor*color_exact_return,<parameter> *color_screen_return</parameter></paramdef>
+ <paramdef>XcmsColorFormat<parameter> result_format</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+<!-- .ds St -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color string(St.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_exact_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the color specification parsed from the color string
+or parsed from the corresponding string found in a color-name database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_screen_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the color that can be reproduced on the screen.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>result_format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color format for the returned color
+specifications (color_screen_return and color_exact_return arguments).
+If the format is
+<symbol>XcmsUndefinedFormat</symbol>
+and the color string contains a
+numerical color specification,
+the specification is returned in the format used in that numerical
+color specification.
+If the format is
+<symbol>XcmsUndefinedFormat</symbol>
+and the color string contains a color name,
+the specification is returned in the format used
+to store the color in the database.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsLookupColor</function>
+function looks up the string name of a color with respect to the screen
+associated with the specified colormap.
+It returns both the exact color values and
+the closest values provided by the screen
+with respect to the visual type of the specified colormap.
+The values are returned in the format specified by result_format.
+If the color name is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+Use of uppercase or lowercase does not matter.
+<function>XcmsLookupColor</function>
+returns
+<symbol>XcmsSuccess</symbol>
+or
+<symbol>XcmsSuccessWithCompression</symbol>
+if the name is resolved; otherwise, it returns
+<symbol>XcmsFailure</symbol>.
+If
+<symbol>XcmsSuccessWithCompression</symbol>
+is returned, the color specification returned in
+color_screen_return is the result of gamut compression.
+</para>
+</sect1>
+
+<sect1 id="Allocating_and_Freeing_Color_Cells">
+<title>Allocating and Freeing Color Cells</title>
+<!-- .XS -->
+<!-- (SN Allocating and Freeing Color Cells -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+There are two ways of allocating color cells:
+explicitly as read-only entries, one pixel value at a time,
+or read/write,
+where you can allocate a number of color cells and planes simultaneously.
+<indexterm><primary>Read-only colormap cells</primary></indexterm>
+A read-only cell has its <acronym>RGB</acronym> value set by the server.
+<indexterm><primary>Read/write colormap cells</primary></indexterm>
+Read/write cells do not have defined colors initially;
+functions described in the next section must be used to store values into them.
+Although it is possible for any client to store values into a read/write
+cell allocated by another client,
+read/write cells normally should be considered private to the client
+that allocated them.
+</para>
+<para>
+<!-- .LP -->
+Read-only colormap cells are shared among clients.
+The server counts each allocation and freeing of the cell by clients.
+When the last client frees a shared cell, the cell is finally deallocated.
+If a single client allocates the same read-only cell multiple
+times, the server counts each such allocation, not just the first one.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To allocate a read-only color cell with an <acronym>RGB</acronym> value, use
+<function>XAllocColor</function>.
+</para>
+<indexterm><primary>Allocation</primary><secondary>read-only colormap cells</secondary></indexterm>
+<indexterm><primary>Read-only colormap cells</primary><secondary>allocating</secondary></indexterm>
+<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
+<indexterm significance="preferred"><primary>XAllocColor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xalloccolor'>
+<funcprototype>
+ <funcdef>Status <function>XAllocColor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>XColor<parameter> *screen_in_out</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies and returns the values actually used in the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAllocColor</function>
+function allocates a read-only colormap entry corresponding to the closest
+<acronym>RGB</acronym> value supported by the hardware.
+<function>XAllocColor</function>
+returns the pixel value of the color closest to the specified
+<acronym>RGB</acronym> elements supported by the hardware
+and returns the <acronym>RGB</acronym> value actually used.
+The corresponding colormap cell is read-only.
+In addition,
+<function>XAllocColor</function>
+returns nonzero if it succeeded or zero if it failed.
+<indexterm><primary>Color map</primary></indexterm>
+<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
+<indexterm><primary>Allocation</primary><secondary>colormap</secondary></indexterm>
+<indexterm><primary>read-only colormap cells</primary></indexterm>
+Multiple clients that request the same effective <acronym>RGB</acronym> value can be assigned
+the same read-only entry, thus allowing entries to be shared.
+When the last client deallocates a shared cell, it is deallocated.
+<function>XAllocColor</function>
+does not use or affect the flags in the
+<structname>XColor</structname>
+structure.
+</para>
+<para>
+<!-- .LP -->
+<function>XAllocColor</function>
+can generate a
+<errorname>BadColor</errorname>
+error.
+<!-- .EQ -->
+delim %%
+<!-- .EN -->
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To allocate a read-only color cell with a color in arbitrary format, use
+<function>XcmsAllocColor</function>.
+</para>
+<indexterm><primary>Allocation</primary><secondary>read-only colormap cells</secondary></indexterm>
+<indexterm><primary>Read-only colormap cells</primary><secondary>allocating</secondary></indexterm>
+<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsAllocColor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsalloccolor'>
+<funcprototype>
+ <funcdef>Status <function>XcmsAllocColor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_in_out</parameter></paramdef>
+ <paramdef>XcmsColorFormat<parameter> result_format</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color to allocate and returns the pixel and color
+that is actually used in the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>result_format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color format for the returned color specification.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsAllocColor</function>
+function is similar to
+<function>XAllocColor</function>
+except the color can be specified in any format.
+The
+<function>XcmsAllocColor</function>
+function ultimately calls
+<function>XAllocColor</function>
+to allocate a read-only color cell (colormap entry) with the specified color.
+<function>XcmsAllocColor</function>
+first converts the color specified
+to an <acronym>RGB</acronym> value and then passes this to
+<function>XAllocColor</function>.
+<function>XcmsAllocColor</function>
+returns the pixel value of the color cell and the color specification
+actually allocated.
+This returned color specification is the result of converting the <acronym>RGB</acronym> value
+returned by
+<function>XAllocColor</function>
+into the format specified with the result_format argument.
+If there is no interest in a returned color specification,
+unnecessary computation can be bypassed if result_format is set to
+<symbol>XcmsRGBFormat</symbol>.
+The corresponding colormap cell is read-only.
+If this routine returns
+<symbol>XcmsFailure</symbol>,
+the color_in_out color specification is left unchanged.
+</para>
+<para>
+<!-- .LP -->
+<function>XcmsAllocColor</function>
+can generate a
+<errorname>BadColor</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To allocate a read-only color cell using a color name and return the closest
+color supported by the hardware in <acronym>RGB</acronym> format, use
+<function>XAllocNamedColor</function>.
+</para>
+<indexterm><primary>Allocation</primary><secondary>read-only colormap cells</secondary></indexterm>
+<indexterm><primary>Read-only colormap cells</primary><secondary>allocating</secondary></indexterm>
+<indexterm><primary>Color</primary><secondary>naming</secondary></indexterm>
+<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
+<indexterm significance="preferred"><primary>XAllocNamedColor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xallocnamedcolor'>
+<funcprototype>
+ <funcdef>Status <function>XAllocNamedColor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>char<parameter> *color_name</parameter></paramdef>
+ <paramdef>XColor*screen_def_return,<parameter> *exact_def_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color name string (for example, red) whose color
+definition structure you want returned.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen_def_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the closest <acronym>RGB</acronym> values provided by the hardware.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>exact_def_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the exact <acronym>RGB</acronym> values.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAllocNamedColor</function>
+function looks up the named color with respect to the screen that is
+associated with the specified colormap.
+It returns both the exact database definition and
+the closest color supported by the screen.
+The allocated color cell is read-only.
+The pixel value is returned in screen_def_return.
+If the color name is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+Use of uppercase or lowercase does not matter.
+If screen_def_return and exact_def_return
+point to the same structure, the pixel field will be set correctly,
+but the color values are undefined.
+<function>XAllocNamedColor</function>
+returns nonzero if a cell is allocated;
+otherwise, it returns zero.
+</para>
+<para>
+<!-- .LP -->
+<function>XAllocNamedColor</function>
+can generate a
+<errorname>BadColor</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To allocate a read-only color cell using a color name and return the closest
+color supported by the hardware in an arbitrary format, use
+<function>XcmsAllocNamedColor</function>.
+</para>
+<indexterm><primary>Allocation</primary><secondary>read-only colormap cells</secondary></indexterm>
+<indexterm><primary>Read-only colormap cells</primary><secondary>allocating</secondary></indexterm>
+<indexterm><primary>Color</primary><secondary>naming</secondary></indexterm>
+<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsAllocNamedColor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsallocnamedcolor'>
+<funcprototype>
+ <funcdef>Status <function>XcmsAllocNamedColor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>char<parameter> *color_string</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_screen_return</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_exact_return</parameter></paramdef>
+ <paramdef>XcmsColorFormat<parameter> result_format</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+<!-- .ds St \ whose color definition structure is to be returned -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color string(St.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_screen_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the pixel value of the color cell and color specification
+that actually is stored for that cell.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_exact_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the color specification parsed from the color string
+or parsed from the corresponding string found in a color-name database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>result_format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color format for the returned color
+specifications (color_screen_return and color_exact_return arguments).
+If the format is
+<symbol>XcmsUndefinedFormat</symbol>
+and the color string contains a
+numerical color specification,
+the specification is returned in the format used in that numerical
+color specification.
+If the format is
+<symbol>XcmsUndefinedFormat</symbol>
+and the color string contains a color name,
+the specification is returned in the format used
+to store the color in the database.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsAllocNamedColor</function>
+function is similar to
+<function>XAllocNamedColor</function>
+except that the color returned can be in any format specified.
+This function
+ultimately calls
+<function>XAllocColor</function>
+to allocate a read-only color cell with
+the color specified by a color string.
+The color string is parsed into an
+<structname>XcmsColor</structname>
+structure (see
+<function>XcmsLookupColor</function>),
+converted
+to an <acronym>RGB</acronym> value, and finally passed to
+<function>XAllocColor</function>.
+If the color name is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+Use of uppercase or lowercase does not matter.
+</para>
+<para>
+<!-- .LP -->
+This function returns both the color specification as a result
+of parsing (exact specification) and the actual color specification
+stored (screen specification).
+This screen specification is the result of converting the <acronym>RGB</acronym> value
+returned by
+<function>XAllocColor</function>
+into the format specified in result_format.
+If there is no interest in a returned color specification,
+unnecessary computation can be bypassed if result_format is set to
+<symbol>XcmsRGBFormat</symbol>.
+If color_screen_return and color_exact_return
+point to the same structure, the pixel field will be set correctly,
+but the color values are undefined.
+</para>
+<para>
+<!-- .LP -->
+<function>XcmsAllocNamedColor</function>
+can generate a
+<errorname>BadColor</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To allocate read/write color cell and color plane combinations for a
+<symbol>PseudoColor</symbol>
+model, use
+<function>XAllocColorCells</function>.
+</para>
+<indexterm><primary>Read/write colormap cells</primary><secondary>allocating</secondary></indexterm>
+<indexterm><primary>Allocation</primary><secondary>read/write colormap cells</secondary></indexterm>
+<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
+<indexterm significance="preferred"><primary>XAllocColorCells</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xalloccolorcells'>
+<funcprototype>
+ <funcdef>Status <function>XAllocColorCells</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>Bool<parameter> contig</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> plane_masks_return[]</parameter></paramdef>
+ <paramdef>unsignedint<parameter> nplanes</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> pixels_return[]</parameter></paramdef>
+ <paramdef>unsignedint<parameter> npixels</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>contig</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value that indicates whether the planes must be contiguous.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>plane_mask_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns an array of plane masks.
+<!-- .\" *** JIM: NEED MORE INFO FOR THIS. *** -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nplanes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of plane masks that are to be returned in the plane masks
+array.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pixels_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns an array of pixel values.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>npixels</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of pixel values that are to be returned in the
+pixels_return array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAllocColorCells</function>
+function allocates read/write color cells.
+The number of colors must be positive and the number of planes nonnegative,
+or a
+<errorname>BadValue</errorname>
+error results.
+If ncolors and nplanes are requested,
+then ncolors pixels
+and nplane plane masks are returned.
+No mask will have any bits set to 1 in common with
+any other mask or with any of the pixels.
+By ORing together each pixel with zero or more masks,
+ncolors &times; 2<superscript><emphasis>nplanes</emphasis></superscript>
+distinct pixels can be produced.
+All of these are
+allocated writable by the request.
+For
+<symbol>GrayScale</symbol>
+or
+<symbol>PseudoColor</symbol>,
+each mask has exactly one bit set to 1.
+For
+<symbol>DirectColor</symbol>,
+each has exactly three bits set to 1.
+If contig is
+<symbol>True</symbol>
+and if all masks are ORed
+together, a single contiguous set of bits set to 1 will be formed for
+<symbol>GrayScale</symbol>
+or
+<symbol>PseudoColor</symbol>
+and three contiguous sets of bits set to 1 (one within each
+pixel subfield) for
+<symbol>DirectColor</symbol>.
+The <acronym>RGB</acronym> values of the allocated
+entries are undefined.
+<function>XAllocColorCells</function>
+returns nonzero if it succeeded or zero if it failed.
+</para>
+<para>
+<!-- .LP -->
+<function>XAllocColorCells</function>
+can generate
+<errorname>BadColor</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To allocate read/write color resources for a
+<symbol>DirectColor</symbol>
+model, use
+<function>XAllocColorPlanes</function>.
+</para>
+<indexterm><primary>Read/write colormap planes</primary><secondary>allocating</secondary></indexterm>
+<indexterm><primary>Allocation</primary><secondary>read/write colormap planes</secondary></indexterm>
+<indexterm><primary>Color</primary><secondary>allocation</secondary></indexterm>
+<indexterm significance="preferred"><primary>XAllocColorPlanes</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xalloccolorplanes'>
+<funcprototype>
+ <funcdef>Status <function>XAllocColorPlanes</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>Bool<parameter> contig</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> pixels_return[]</parameter></paramdef>
+ <paramdef>int<parameter> ncolors</parameter></paramdef>
+ <paramdef>intnreds,ngreens,<parameter> nblues</parameter></paramdef>
+ <paramdef>unsignedlong*rmask_return,*gmask_return,<parameter> *bmask_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>contig</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value that indicates whether the planes must be contiguous.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pixels_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns an array of pixel values.
+<function>XAllocColorPlanes</function>
+returns the pixel values in this array.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ncolors</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of pixel values that are to be returned in the
+pixels_return array.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nreds</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ngreens</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nblues</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+Specify the number of red, green, and blue planes.
+The value you pass must be nonnegative.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rmask_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gmask_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bmask_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return bit masks for the red, green, and blue planes.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The specified ncolors must be positive;
+and nreds, ngreens, and nblues must be nonnegative,
+or a
+<errorname>BadValue</errorname>
+error results.
+If ncolors colors, nreds reds, ngreens greens, and nblues blues are requested,
+ncolors pixels are returned; and the masks have nreds, ngreens, and
+nblues bits set to 1, respectively.
+If contig is
+<symbol>True</symbol>,
+each mask will have
+a contiguous set of bits set to 1.
+No mask will have any bits set to 1 in common with
+any other mask or with any of the pixels.
+For
+<symbol>DirectColor</symbol>,
+each mask
+will lie within the corresponding pixel subfield.
+By ORing together
+subsets of masks with each pixel value,
+ncolors &times; 2<superscript><emphasis>(nreds+ngreens+nblues)</emphasis></superscript>
+distinct pixel values can be produced.
+All of these are allocated by the request.
+However, in the
+colormap, there are only
+ncolors &times; 2<superscript><emphasis>nreds</emphasis></superscript>
+independent red entries,
+ncolors &times; 2<superscript><emphasis>ngreens</emphasis></superscript>
+independent green entries, and
+ncolors &times; 2<superscript><emphasis>nblues</emphasis></superscript>
+independent blue entries.
+This is true even for
+<symbol>PseudoColor</symbol>.
+When the colormap entry of a pixel
+value is changed (using
+<function>XStoreColors</function>,
+<function>XStoreColor</function>,
+or
+<function>XStoreNamedColor</function>),
+the pixel is decomposed according to the masks,
+and the corresponding independent entries are updated.
+<function>XAllocColorPlanes</function>
+returns nonzero if it succeeded or zero if it failed.
+</para>
+<para>
+<!-- .LP -->
+<function>XAllocColorPlanes</function>
+can generate
+<errorname>BadColor</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+<indexterm><primary>Freeing</primary><secondary>colors</secondary></indexterm>
+To free colormap cells, use
+<function>XFreeColors</function>.
+<indexterm significance="preferred"><primary>XFreeColors</primary></indexterm>
+<indexterm><primary>Color</primary><secondary>deallocation</secondary></indexterm>
+<!-- .sM -->
+</para>
+<funcsynopsis id='xfreecolors'>
+<funcprototype>
+ <funcdef><function>XFreeColors</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> pixels[]</parameter></paramdef>
+ <paramdef>int<parameter> npixels</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> planes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+<!-- .ds Pi that map to the cells in the specified colormap -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pixels</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of pixel values (Pi.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>npixels</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of pixels.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>planes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the planes you want to free.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreeColors</function>
+function frees the cells represented by pixels whose values are in the
+pixels array.
+The planes argument should not have any bits set to 1 in common with any of the
+pixels.
+The set of all pixels is produced by ORing together subsets of
+the planes argument with the pixels.
+The request frees all of these pixels that
+were allocated by the client (using
+<indexterm><primary>XAllocColor</primary></indexterm>
+<indexterm><primary>XAllocNamedColor</primary></indexterm>
+<indexterm><primary>XAllocColorCells</primary></indexterm>
+<indexterm><primary>XAllocColorPlanes</primary></indexterm>
+<function>XAllocColor</function>,
+<function>XAllocNamedColor</function>,
+<function>XAllocColorCells</function>,
+and
+<function>XAllocColorPlanes</function>).
+Note that freeing an
+individual pixel obtained from
+<function>XAllocColorPlanes</function>
+may not actually allow
+it to be reused until all of its related pixels are also freed.
+Similarly,
+a read-only entry is not actually freed until it has been freed by all clients,
+and if a client allocates the same read-only entry multiple times,
+it must free the entry that many times before the entry is actually freed.
+</para>
+<para>
+<!-- .LP -->
+All specified pixels that are allocated by the client in the colormap are
+freed, even if one or more pixels produce an error.
+If a specified pixel is not a valid index into the colormap, a
+<errorname>BadValue</errorname>
+error results.
+If a specified pixel is not allocated by the
+client (that is, is unallocated or is only allocated by another client)
+or if the colormap was created with all entries writable (by passing
+<symbol>AllocAll</symbol>
+to
+<function>XCreateColormap</function>),
+a
+<errorname>BadAccess</errorname>
+error results.
+If more than one pixel is in error,
+the one that gets reported is arbitrary.
+</para>
+<para>
+<!-- .LP -->
+<function>XFreeColors</function>
+can generate
+<errorname>BadAccess</errorname>,
+<errorname>BadColor</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+</sect1>
+<sect1 id="Modifying_and_Querying_Colormap_Cells">
+<title>Modifying and Querying Colormap Cells</title>
+<!-- .XS -->
+<!-- (SN Modifying and Querying Colormap Cells -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To store an <acronym>RGB</acronym> value in a single colormap cell, use
+<function>XStoreColor</function>.
+</para>
+<indexterm><primary>Color</primary><secondary>storing</secondary></indexterm>
+<indexterm significance="preferred"><primary>XStoreColor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xstorecolor'>
+<funcprototype>
+ <funcdef><function>XStoreColor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>XColor<parameter> *color</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the pixel and <acronym>RGB</acronym> values.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XStoreColor</function>
+function changes the colormap entry of the pixel value specified in the
+pixel member of the
+<structname>XColor</structname>
+structure.
+You specified this value in the
+pixel member of the
+<structname>XColor</structname>
+structure.
+This pixel value must be a read/write cell and a valid index into the colormap.
+If a specified pixel is not a valid index into the colormap,
+a
+<errorname>BadValue</errorname>
+error results.
+<function>XStoreColor</function>
+also changes the red, green, and/or blue color components.
+You specify which color components are to be changed by setting
+<symbol>DoRed</symbol>,
+<symbol>DoGreen</symbol>,
+and/or
+<symbol>DoBlue</symbol>
+in the flags member of the
+<structname>XColor</structname>
+structure.
+If the colormap is an installed map for its screen,
+the changes are visible immediately.
+</para>
+<para>
+<!-- .LP -->
+<function>XStoreColor</function>
+can generate
+<errorname>BadAccess</errorname>,
+<errorname>BadColor</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To store multiple <acronym>RGB</acronym> values in multiple colormap cells, use
+<function>XStoreColors</function>.
+</para>
+<indexterm><primary>Color</primary><secondary>storing</secondary></indexterm>
+<indexterm significance="preferred"><primary>XStoreColors</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xstorecolors'>
+<funcprototype>
+ <funcdef><function>XStoreColors</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>XColor<parameter> color[]</parameter></paramdef>
+ <paramdef>int<parameter> ncolors</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of color definition structures to be stored.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ncolors</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .\"Specifies the number of color definition structures. -->
+Specifies the number of
+<structname>XColor</structname>
+structures in the color definition array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XStoreColors</function>
+function changes the colormap entries of the pixel values
+specified in the pixel members of the
+<structname>XColor</structname>
+structures.
+You specify which color components are to be changed by setting
+<symbol>DoRed</symbol>,
+<symbol>DoGreen</symbol>,
+and/or
+<symbol>DoBlue</symbol>
+in the flags member of the
+<structname>XColor</structname>
+structures.
+If the colormap is an installed map for its screen, the
+changes are visible immediately.
+<function>XStoreColors</function>
+changes the specified pixels if they are allocated writable in the colormap
+by any client, even if one or more pixels generates an error.
+If a specified pixel is not a valid index into the colormap, a
+<errorname>BadValue</errorname>
+error results.
+If a specified pixel either is unallocated or is allocated read-only, a
+<errorname>BadAccess</errorname>
+error results.
+If more than one pixel is in error,
+the one that gets reported is arbitrary.
+</para>
+<para>
+<!-- .LP -->
+<function>XStoreColors</function>
+can generate
+<errorname>BadAccess</errorname>,
+<errorname>BadColor</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To store a color of arbitrary format in a single colormap cell, use
+<function>XcmsStoreColor</function>.
+</para>
+<indexterm><primary>Color</primary><secondary>storing</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsStoreColor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsstorecolor'>
+<funcprototype>
+ <funcdef>Status <function>XcmsStoreColor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color cell and the color to store.
+Values specified in this
+<structname>XcmsColor</structname>
+structure remain unchanged on return.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsStoreColor</function>
+function converts the color specified in the
+<structname>XcmsColor</structname>
+structure into <acronym>RGB</acronym> values.
+It then uses this <acronym>RGB</acronym> specification in an
+<structname>XColor</structname>
+structure, whose three flags
+(<symbol>DoRed</symbol>,
+<symbol>DoGreen</symbol>,
+and
+<symbol>DoBlue</symbol>)
+are set, in a call to
+<function>XStoreColor</function>
+to change the color cell specified by the pixel member of the
+<structname>XcmsColor</structname>
+structure.
+This pixel value must be a valid index for the specified colormap,
+and the color cell specified by the pixel value must be a read/write cell.
+If the pixel value is not a valid index, a
+<errorname>BadValue</errorname>
+error results.
+If the color cell is unallocated or is allocated read-only, a
+<errorname>BadAccess</errorname>
+error results.
+If the colormap is an installed map for its screen,
+the changes are visible immediately.
+</para>
+<para>
+<!-- .LP -->
+Note that
+<function>XStoreColor</function>
+has no return value; therefore, an
+<symbol>XcmsSuccess</symbol>
+return value from this function indicates that the conversion
+to <acronym>RGB</acronym> succeeded and the call to
+<function>XStoreColor</function>
+was made.
+To obtain the actual color stored, use
+<function>XcmsQueryColor</function>.
+Because of the screen's hardware limitations or gamut compression,
+the color stored in the colormap may not be identical
+to the color specified.
+</para>
+<para>
+<!-- .LP -->
+<function>XcmsStoreColor</function>
+can generate
+<errorname>BadAccess</errorname>,
+<errorname>BadColor</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To store multiple colors of arbitrary format in multiple colormap cells, use
+<function>XcmsStoreColors</function>.
+</para>
+<indexterm><primary>Color</primary><secondary>storing</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsStoreColors</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsstorecolors'>
+<funcprototype>
+ <funcdef>Status <function>XcmsStoreColors</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> colors[]</parameter></paramdef>
+ <paramdef>int<parameter> ncolors</parameter></paramdef>
+ <paramdef>Bool<parameter> compression_flags_return[]</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colors</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color specification array of
+<structname>XcmsColor</structname>
+structures, each specifying a color cell and the color to store in that
+cell.
+Values specified in the array remain unchanged upon return.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ncolors</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of
+<structname>XcmsColor</structname>
+structures in the color-specification array.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>compression_flags_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns an array of Boolean values indicating compression status.
+If a non-NULL pointer is supplied,
+each element of the array is set to
+<symbol>True</symbol>
+if the corresponding color was compressed and
+<symbol>False</symbol>
+otherwise.
+Pass NULL if the compression status is not useful.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsStoreColors</function>
+function converts the colors specified in the array of
+<structname>XcmsColor</structname>
+structures into <acronym>RGB</acronym> values and then uses these <acronym>RGB</acronym> specifications in
+<structname>XColor</structname>
+structures, whose three flags
+(<symbol>DoRed</symbol>,
+<symbol>DoGreen</symbol>,
+and
+<symbol>DoBlue</symbol>)
+are set, in a call to
+<function>XStoreColors</function>
+to change the color cells specified by the pixel member of the corresponding
+<structname>XcmsColor</structname>
+structure.
+Each pixel value must be a valid index for the specified colormap,
+and the color cell specified by each pixel value must be a read/write cell.
+If a pixel value is not a valid index, a
+<errorname>BadValue</errorname>
+error results.
+If a color cell is unallocated or is allocated read-only, a
+<errorname>BadAccess</errorname>
+error results.
+If more than one pixel is in error,
+the one that gets reported is arbitrary.
+If the colormap is an installed map for its screen,
+the changes are visible immediately.
+</para>
+<para>
+<!-- .LP -->
+Note that
+<function>XStoreColors</function>
+has no return value; therefore, an
+<symbol>XcmsSuccess</symbol>
+return value from this function indicates that conversions
+to <acronym>RGB</acronym> succeeded and the call to
+<function>XStoreColors</function>
+was made.
+To obtain the actual colors stored, use
+<function>XcmsQueryColors</function>.
+Because of the screen's hardware limitations or gamut compression,
+the colors stored in the colormap may not be identical
+to the colors specified.
+</para>
+<para>
+<!-- .LP -->
+<function>XcmsStoreColors</function>
+can generate
+<errorname>BadAccess</errorname>,
+<errorname>BadColor</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To store a color specified by name in a single colormap cell, use
+<function>XStoreNamedColor</function>.
+</para>
+<indexterm><primary>Color</primary><secondary>storing</secondary></indexterm>
+<indexterm><primary>Color</primary><secondary>naming</secondary></indexterm>
+<indexterm significance="preferred"><primary>XStoreNamedColor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xstorenamedcolor'>
+<funcprototype>
+ <funcdef><function>XStoreNamedColor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>char<parameter> *color</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> pixel</parameter></paramdef>
+ <paramdef>int<parameter> flags</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color name string (for example, red).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pixel</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the entry in the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>flags</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which red, green, and blue components are set.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XStoreNamedColor</function>
+function looks up the named color with respect to the screen associated with
+the colormap and stores the result in the specified colormap.
+The pixel argument determines the entry in the colormap.
+The flags argument determines which of the red, green, and blue components
+are set.
+You can set this member to the
+bitwise inclusive OR of the bits
+<symbol>DoRed</symbol>,
+<symbol>DoGreen</symbol>,
+and
+<symbol>DoBlue</symbol>.
+If the color name is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+Use of uppercase or lowercase does not matter.
+If the specified pixel is not a valid index into the colormap, a
+<errorname>BadValue</errorname>
+error results.
+If the specified pixel either is unallocated or is allocated read-only, a
+<errorname>BadAccess</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XStoreNamedColor</function>
+can generate
+<errorname>BadAccess</errorname>,
+<errorname>BadColor</errorname>,
+<errorname>BadName</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+The
+<function>XQueryColor</function>
+and
+<function>XQueryColors</function>
+functions take pixel values in the pixel member of
+<structname>XColor</structname>
+structures and store in the structures the <acronym>RGB</acronym> values for those
+pixels from the specified colormap.
+The values returned for an unallocated entry are undefined.
+These functions also set the flags member in the
+<structname>XColor</structname>
+structure to all three colors.
+If a pixel is not a valid index into the specified colormap, a
+<errorname>BadValue</errorname>
+error results.
+If more than one pixel is in error,
+the one that gets reported is arbitrary.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To query the <acronym>RGB</acronym> value of a single colormap cell, use
+<function>XQueryColor</function>.
+</para>
+<indexterm><primary>Color</primary><secondary>querying</secondary></indexterm>
+<indexterm significance="preferred"><primary>XQueryColor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xquerycolor'>
+<funcprototype>
+ <funcdef><function>XQueryColor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>XColor<parameter> *def_in_out</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>def_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies and returns the <acronym>RGB</acronym> values for the pixel specified in the structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XQueryColor</function>
+function returns the current <acronym>RGB</acronym> value for the pixel in the
+<structname>XColor</structname>
+structure and sets the
+<symbol>DoRed</symbol>,
+<symbol>DoGreen</symbol>,
+and
+<symbol>DoBlue</symbol>
+flags.
+</para>
+<para>
+<!-- .LP -->
+<function>XQueryColor</function>
+can generate
+<errorname>BadColor</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To query the <acronym>RGB</acronym> values of multiple colormap cells, use
+<function>XQueryColors</function>.
+</para>
+<indexterm><primary>Color</primary><secondary>querying</secondary></indexterm>
+<indexterm significance="preferred"><primary>XQueryColors</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xquerycolors'>
+<funcprototype>
+ <funcdef><function>XQueryColors</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>XColor<parameter> defs_in_out[]</parameter></paramdef>
+ <paramdef>int<parameter> ncolors</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>defs_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies and returns an array of color definition structures for the pixel
+specified in the structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ncolors</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .\"Specifies the number of color definition structures. -->
+Specifies the number of
+<structname>XColor</structname>
+structures in the color definition array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XQueryColors</function>
+function returns the <acronym>RGB</acronym> value for each pixel in each
+<structname>XColor</structname>
+structure and sets the
+<symbol>DoRed</symbol>,
+<symbol>DoGreen</symbol>,
+and
+<symbol>DoBlue</symbol>
+flags in each structure.
+
+</para>
+<para>
+<!-- .LP -->
+<function>XQueryColors</function>
+can generate
+<errorname>BadColor</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To query the color of a single colormap cell in an arbitrary format, use
+<function>XcmsQueryColor</function>.
+</para>
+<indexterm><primary>Color</primary><secondary>querying</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsQueryColor</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsquerycolor'>
+<funcprototype>
+ <funcdef>Status <function>XcmsQueryColor</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_in_out</parameter></paramdef>
+ <paramdef>XcmsColorFormat<parameter> result_format</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the pixel member that indicates the color cell to query.
+The color specification stored for the color cell is returned in this
+<structname>XcmsColor</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>result_format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color format for the returned color specification.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsQueryColor</function>
+function obtains the <acronym>RGB</acronym> value
+for the pixel value in the pixel member of the specified
+<structname>XcmsColor</structname>
+structure and then
+converts the value to the target format as
+specified by the result_format argument.
+If the pixel is not a valid index in the specified colormap, a
+<errorname>BadValue</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XcmsQueryColor</function>
+can generate
+<errorname>BadColor</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To query the color of multiple colormap cells in an arbitrary format, use
+<function>XcmsQueryColors</function>.
+</para>
+<indexterm><primary>Color</primary><secondary>querying</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsQueryColors</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsquerycolors'>
+<funcprototype>
+ <funcdef>Status <function>XcmsQueryColors</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> colors_in_out[]</parameter></paramdef>
+ <paramdef>unsignedint<parameter> ncolors</parameter></paramdef>
+ <paramdef>XcmsColorFormat<parameter> result_format</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colors_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of
+<structname>XcmsColor</structname>
+structures, each pixel member indicating the color cell to query.
+The color specifications for the color cells are returned in these structures.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ncolors</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of
+<structname>XcmsColor</structname>
+structures in the color-specification array.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>result_format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color format for the returned color specification.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsQueryColors</function>
+function obtains the <acronym>RGB</acronym> values
+for pixel values in the pixel members of
+<structname>XcmsColor</structname>
+structures and then
+converts the values to the target format as
+specified by the result_format argument.
+If a pixel is not a valid index into the specified colormap, a
+<errorname>BadValue</errorname>
+error results.
+If more than one pixel is in error,
+the one that gets reported is arbitrary.
+</para>
+<para>
+<!-- .LP -->
+<function>XcmsQueryColors</function>
+can generate
+<errorname>BadColor</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+</sect1>
+<sect1 id="Color_Conversion_Context_Functions">
+<title>Color Conversion Context Functions</title>
+<!-- .XS -->
+<!-- (SN Color Conversion Context Functions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This section describes functions to create, modify,
+and query Color Conversion Contexts (CCCs).
+</para>
+<para>
+<!-- .LP -->
+Associated with each colormap is an initial CCC transparently generated by
+Xlib.
+<indexterm><primary>Color Conversion Context</primary><secondary>creation</secondary></indexterm>
+Therefore, when you specify a colormap as an argument to a function,
+you are indirectly specifying a CCC.
+<indexterm><primary>CCC</primary><secondary>of colormap</secondary></indexterm>
+<indexterm><primary>Color Conversion Context</primary><secondary>of colormap</secondary></indexterm>
+The CCC attributes that can be modified by the X client are:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Client White Point
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Gamut compression procedure and client data
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+White point adjustment procedure and client data
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The initial values for these attributes are implementation specific.
+The CCC attributes for subsequently created CCCs can be defined
+by changing the CCC attributes of the default CCC.
+<indexterm><primary>CCC</primary><secondary>default</secondary></indexterm>
+<indexterm><primary>Color Conversion Context</primary><secondary>default</secondary></indexterm>
+There is a default CCC associated with each screen.
+</para>
+<sect2 id="Getting_and_Setting_the_Color_Conversion_Context_of_a_Colormap">
+<title>Getting and Setting the Color Conversion Context of a Colormap</title>
+<!-- .XS -->
+<!-- (SN Getting and Setting the Color Conversion Context of a Colormap -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the CCC associated with a colormap, use
+<function>XcmsCCCOfColormap</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsCCCOfColormap</primary></indexterm>
+<indexterm><primary>Colormap</primary><secondary>CCC of</secondary></indexterm>
+<indexterm><primary>CCC</primary><secondary>of colormap</secondary></indexterm>
+<indexterm><primary>Color Conversion Context</primary><secondary>of colormap</secondary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmscccofcolormap'>
+<funcprototype>
+ <funcdef>XcmsCCC <function>XcmsCCCOfColormap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsCCCOfColormap</function>
+function returns the CCC associated with the specified colormap.
+Once obtained,
+the CCC attributes can be queried or modified.
+Unless the CCC associated with the specified colormap is changed with
+<function>XcmsSetCCCOfColormap</function>,
+this CCC is used when the specified colormap is used as an argument
+to color functions.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To change the CCC associated with a colormap, use
+<function>XcmsSetCCCOfColormap</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsSetCCCOfColormap</primary></indexterm>
+<indexterm><primary>Colormap</primary><secondary>CCC of</secondary></indexterm>
+<indexterm><primary>CCC</primary><secondary>of colormap</secondary></indexterm>
+<indexterm><primary>Color Conversion Context</primary><secondary>of colormap</secondary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmssetcccofcolormap'>
+<funcprototype>
+ <funcdef>XcmsCCC <function>XcmsSetCCCOfColormap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsSetCCCOfColormap</function>
+function changes the CCC associated with the specified colormap.
+It returns the CCC previously associated with the colormap.
+If they are not used again in the application,
+CCCs should be freed by calling
+<function>XcmsFreeCCC</function>.
+Several colormaps may share the same CCC without restriction; this
+includes the CCCs generated by Xlib with each colormap. Xlib, however,
+creates a new CCC with each new colormap.
+</para>
+</sect2>
+<sect2 id="Obtaining_the_Default_Color_Conversion_Context">
+<title>Obtaining the Default Color Conversion Context</title>
+<!-- .XS -->
+<!-- (SN Obtaining the Default Color Conversion Context -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+You can change the default CCC attributes for subsequently created CCCs
+by changing the CCC attributes of the default CCC.
+<indexterm><primary>CCC</primary><secondary>default</secondary></indexterm>
+<indexterm><primary>Color Conversion Context</primary><secondary>default</secondary></indexterm>
+A default CCC is associated with each screen.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the default CCC for a screen, use
+<function>XcmsDefaultCCC</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsDefaultCCC</primary></indexterm>
+<indexterm><primary>Color Conversion Context</primary><secondary>default</secondary></indexterm>
+<indexterm><primary>CCC</primary><secondary>default</secondary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsdefaultccc'>
+<funcprototype>
+ <funcdef>XcmsCCC <function>XcmsDefaultCCC</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> screen_number</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen_number</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the appropriate screen number on the host server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsDefaultCCC</function>
+function returns the default CCC for the specified screen.
+Its visual is the default visual of the screen.
+Its initial gamut compression and white point
+adjustment procedures as well as the associated client data are implementation
+specific.
+</para>
+</sect2>
+<sect2 id="Color_Conversion_Context_Macros">
+<title>Color Conversion Context Macros</title>
+<!-- .XS -->
+<!-- (SN Color Conversion Context Macros -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Applications should not directly modify any part of the
+<structname>XcmsCCC</structname>.
+The following lists the C language macros, their corresponding function
+equivalents for other language bindings, and what data they both
+can return.
+<!-- .sp -->
+</para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>DisplayOfCCC</primary></indexterm>
+<indexterm significance="preferred"><primary>XcmsDisplayOfCCC</primary></indexterm>
+<!-- .sM -->
+
+<funcsynopsis id='displayofccc'>
+<funcprototype>
+ <funcdef><function>DisplayOfCCC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<funcsynopsis id='xcmsdisplayofccc'>
+<funcprototype>
+ <funcdef>Display *<function>XcmsDisplayOfCCC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Both return the display associated with the specified CCC.
+</para>
+<!-- .LP -->
+<!-- .sp -->
+<indexterm significance="preferred"><primary>VisualOfCCC</primary></indexterm>
+<indexterm significance="preferred"><primary>XcmsVisualOfCCC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='visualofccc'>
+<funcprototype>
+ <funcdef><function>VisualOfCCC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<funcsynopsis id='xcmsvisualofccc'>
+<funcprototype>
+ <funcdef>Visual *<function>XcmsVisualOfCCC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Both return the visual associated with the specified CCC.
+<!-- .sp -->
+</para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>ScreenNumberOfCCC</primary></indexterm>
+<indexterm significance="preferred"><primary>XcmsScreenNumberOfCCC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='screennumberofccc'>
+<funcprototype>
+ <funcdef><function>ScreenNumberOfCCC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<funcsynopsis id='xcmsscreennumberofccc'>
+<funcprototype>
+ <funcdef>int <function>XcmsScreenNumberOfCCC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Both return the number of the screen associated with the specified CCC.
+<!-- .sp -->
+</para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>ScreenWhitePointOfCCC</primary></indexterm>
+<indexterm significance="preferred"><primary>XcmsScreenWhitePointOfCCC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='screenwhitepointofccc'>
+<funcprototype>
+ <funcdef><function>ScreenWhitePointOfCCC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<funcsynopsis id='xcmsscreenwhitepointofccc'>
+<funcprototype>
+ <funcdef>XcmsColor <function>XcmsScreenWhitePointOfCCC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Both return the white point of the screen associated with the specified CCC.
+<!-- .sp -->
+</para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>ClientWhitePointOfCCC</primary></indexterm>
+<indexterm significance="preferred"><primary>XcmsClientWhitePointOfCCC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='clientwhitepointofccc'>
+<funcprototype>
+ <funcdef> <function>ClientWhitePointOfCCC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<funcsynopsis id='xcmsclientwhitepointofccc'>
+<funcprototype>
+ <funcdef>XcmsColor *<function>XcmsClientWhitePointOfCCC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Both return the Client White Point of the specified CCC.
+</para>
+</sect2>
+
+<sect2 id="Modifying_Attributes_of_a_Color_Conversion_Context">
+<title>Modifying Attributes of a Color Conversion Context</title>
+<!-- .XS -->
+<!-- (SN Modifying Attributes of a Color Conversion Context -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To set the Client White Point in the CCC, use
+<function>XcmsSetWhitePoint</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsSetWhitePoint</primary></indexterm>
+<indexterm><primary>Client White Point</primary><secondary>of Color Conversion Context</secondary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmssetwhitepoint'>
+<funcprototype>
+ <funcdef>Status <function>XcmsSetWhitePoint</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+<!-- .ds Co new Client White Point -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the new Client White Point.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsSetWhitePoint</function>
+function changes the Client White Point in the specified CCC.
+Note that the pixel member is ignored
+and that the color specification is left unchanged upon return.
+The format for the new white point must be
+<symbol>XcmsCIEXYZFormat</symbol>,
+<symbol>XcmsCIEuvYFormat</symbol>,
+<symbol>XcmsCIExyYFormat</symbol>,
+or
+<symbol>XcmsUndefinedFormat</symbol>.
+If the color argument is NULL, this function sets the format component of the
+Client White Point specification to
+<symbol>XcmsUndefinedFormat</symbol>,
+indicating that the Client White Point is assumed to be the same as the
+Screen White Point.
+</para>
+<para>
+<!-- .LP -->
+This function returns nonzero status
+if the format for the new white point is valid;
+otherwise, it returns zero.
+
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set the gamut compression procedure and corresponding client data
+in a specified CCC, use
+<function>XcmsSetCompressionProc</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsSetCompressionProc</primary></indexterm>
+<indexterm><primary>Gamut compression</primary><secondary>setting in Color Conversion Context</secondary></indexterm>
+<indexterm><primary>Gamut compression</primary><secondary>procedure</secondary></indexterm>
+<indexterm><primary>Gamut compression</primary><secondary>client data</secondary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmssetcompressionproc'>
+<funcprototype>
+ <funcdef>XcmsCompressionProc <function>XcmsSetCompressionProc</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsCompressionProc<parameter> compression_proc</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>compression_proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the gamut compression procedure that is to be applied
+when a color lies outside the screen's color gamut.
+If NULL is specified and a function using this CCC must convert
+a color specification to a device-dependent format and encounters a color
+that lies outside the screen's color gamut,
+that function will return
+<symbol>XcmsFailure</symbol>.
+<!-- .ds Cd the gamut compression procedure -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies client data for gamut compression procedure or NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsSetCompressionProc</function>
+function first sets the gamut compression procedure and client data
+in the specified CCC with the newly specified procedure and client data
+and then returns the old procedure.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set the white point adjustment procedure and corresponding client data
+in a specified CCC, use
+<function>XcmsSetWhiteAdjustProc</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsSetWhiteAdjustProc</primary></indexterm>
+<indexterm><primary>White point adjustment</primary><secondary>setting in Color Conversion Context</secondary></indexterm>
+<indexterm><primary>White point adjustment</primary><secondary>procedure</secondary></indexterm>
+<indexterm><primary>White point adjustment</primary><secondary>client data</secondary></indexterm>
+<funcsynopsis id='xcmssetwhiteadjustproc'>
+<funcprototype>
+ <funcdef>XcmsWhiteAdjustProc <function>XcmsSetWhiteAdjustProc</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsWhiteAdjustProc<parameter> white_adjust_proc</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>white_adjust_proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the white point adjustment procedure.
+<!-- .ds Cd the white point adjustment procedure -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies client data for white point adjustment procedure or NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsSetWhiteAdjustProc</function>
+function first sets the white point adjustment procedure and client data
+in the specified CCC with the newly specified procedure and client data
+and then returns the old procedure.
+</para>
+</sect2>
+<sect2 id="Creating_and_Freeing_a_Color_Conversion_Context">
+<title>Creating and Freeing a Color Conversion Context</title>
+<!-- .XS -->
+<!-- (SN Creating and Freeing a Color Conversion Context -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+You can explicitly create a CCC within your application by calling
+<function>XcmsCreateCCC</function>.
+These created CCCs can then be used by those functions that explicitly
+call for a CCC argument.
+Old CCCs that will not be used by the application should be freed using
+<function>XcmsFreeCCC</function>.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To create a CCC, use
+<function>XcmsCreateCCC</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsCreateCCC</primary></indexterm>
+<indexterm><primary>Color Conversion Context</primary><secondary>creation</secondary></indexterm>
+<indexterm><primary>CCC</primary><secondary>creation</secondary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmscreateccc'>
+<funcprototype>
+ <funcdef>XcmsCCC <function>XcmsCreateCCC</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> screen_number</parameter></paramdef>
+ <paramdef>Visual<parameter> *visual</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *client_white_point</parameter></paramdef>
+ <paramdef>XcmsCompressionProc<parameter> compression_proc</parameter></paramdef>
+ <paramdef>XPointer<parameter> compression_client_data</parameter></paramdef>
+ <paramdef>XcmsWhiteAdjustProc<parameter> white_adjust_proc</parameter></paramdef>
+ <paramdef>XPointer<parameter> white_adjust_client_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen_number</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the appropriate screen number on the host server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>visual</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the visual type.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_white_point</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the Client White Point.
+If NULL is specified,
+the Client White Point is to be assumed to be the same as the
+Screen White Point.
+Note that the pixel member is ignored.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>compression_proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the gamut compression procedure that is to be applied
+when a color lies outside the screen's color gamut.
+If NULL is specified and a function using this CCC must convert
+a color specification to a device-dependent format and encounters a color
+that lies outside the screen's color gamut,
+that function will return
+<symbol>XcmsFailure</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>compression_client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies client data for use by the gamut compression procedure or NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>white_adjust_proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the white adjustment procedure that is to be applied
+when the Client White Point differs from the Screen White Point.
+NULL indicates that no white point adjustment is desired.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>white_adjust_client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies client data for use with the white point adjustment procedure or NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsCreateCCC</function>
+function creates a CCC for the specified display, screen, and visual.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To free a CCC, use
+<function>XcmsFreeCCC</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsFreeCCC</primary></indexterm>
+<indexterm><primary>Color Conversion Context</primary><secondary>freeing</secondary></indexterm>
+<indexterm><primary>CCC</primary><secondary>freeing</secondary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsfreeccc'>
+<funcprototype>
+ <funcdef>void <function>XcmsFreeCCC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsFreeCCC</function>
+function frees the memory used for the specified CCC.
+Note that default CCCs and those currently associated with colormaps
+are ignored.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Converting_between_Color_Spaces">
+<title>Converting between Color Spaces</title>
+<!-- .XS -->
+<!-- (SN Converting between Color Spaces -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To convert an array of color specifications in arbitrary color formats
+to a single destination format, use
+<function>XcmsConvertColors</function>.
+</para>
+<indexterm><primary>Color conversion</primary></indexterm>
+<indexterm><primary>Color</primary><secondary>conversion</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsConvertColors</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsconvertcolors'>
+<funcprototype>
+ <funcdef>Status <function>XcmsConvertColors</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> colors_in_out[]</parameter></paramdef>
+ <paramdef>unsignedint<parameter> ncolors</parameter></paramdef>
+ <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
+ <paramdef>Bool<parameter> compression_flags_return[]</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+If conversion is between device-independent color spaces only
+(for example, TekHVC to CIELuv),
+the CCC is necessary only to specify the Client White Point.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colors_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of color specifications.
+Pixel members are ignored and remain unchanged upon return.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ncolors</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of
+<structname>XcmsColor</structname>
+structures in the color-specification array.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>target_format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the target color specification format.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>compression_flags_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns an array of Boolean values indicating compression status.
+If a non-NULL pointer is supplied,
+each element of the array is set to
+<symbol>True</symbol>
+if the corresponding color was compressed and
+<symbol>False</symbol>
+otherwise.
+Pass NULL if the compression status is not useful.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsConvertColors</function>
+function converts the color specifications in the specified array of
+<structname>XcmsColor</structname>
+structures from their current format to a single target format,
+using the specified CCC.
+When the return value is
+<symbol>XcmsFailure</symbol>,
+the contents of the color specification array are left unchanged.
+</para>
+<para>
+<!-- .LP -->
+The array may contain a mixture of color specification formats
+(for example, 3 <acronym>CIE</acronym> XYZ, 2 <acronym>CIE</acronym> Luv, and so on).
+When the array contains both device-independent and
+device-dependent color specifications and the target_format argument specifies
+a device-dependent format (for example,
+<symbol>XcmsRGBiFormat</symbol>,
+<symbol>XcmsRGBFormat</symbol>),
+all specifications are converted to <acronym>CIE</acronym> XYZ format and then to the target
+device-dependent format.
+</para>
+</sect1>
+<sect1 id="Callback_Functions">
+<title>Callback Functions</title>
+<!-- .XS -->
+<!-- (SN Callback Functions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This section describes the gamut compression and white point
+adjustment callbacks.
+</para>
+<para>
+<!-- .LP -->
+The gamut compression procedure specified in the CCC
+is called when an attempt to convert a color specification from
+<structname>XcmsCIEXYZ</structname>
+to a device-dependent format (typically
+<structname>XcmsRGBi</structname>)
+results in a color that lies outside the screen's color gamut.
+If the gamut compression procedure requires client data, this data is passed
+via the gamut compression client data in the CCC.
+</para>
+<para>
+<!-- .LP -->
+During color specification conversion between device-independent
+and device-dependent color spaces,
+if a white point adjustment procedure is specified in the CCC,
+it is triggered when the Client White Point and Screen White Point differ.
+If required, the client data is obtained from the CCC.
+</para>
+<sect2 id="Prototype_Gamut_Compression_Procedure">
+<title>Prototype Gamut Compression Procedure</title>
+<!-- .XS -->
+<!-- (SN Prototype Gamut Compression Procedure -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The gamut compression callback interface must adhere to the
+following:
+</para>
+<indexterm significance="preferred"><primary>XcmsCompressionProc</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmscompressionproc'>
+<funcprototype>
+ <funcdef>typedef Status<function>(*XcmsCompressionProc</function>)</funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> colors_in_out[]</parameter></paramdef>
+ <paramdef>unsignedint<parameter> ncolors</parameter></paramdef>
+ <paramdef>unsignedint<parameter> index</parameter></paramdef>
+ <paramdef>Bool<parameter> compression_flags_return[]</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colors_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of color specifications.
+Pixel members should be ignored and must remain unchanged upon return.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ncolors</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of
+<structname>XcmsColor</structname>
+structures in the color-specification array.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>index</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the index into the array of
+<structname>XcmsColor</structname>
+structures for the encountered color specification that lies outside the
+screen's color gamut.
+Valid values are 0 (for the first element) to ncolors - 1.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>compression_flags_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns an array of Boolean values for indicating compression status.
+If a non-NULL pointer is supplied
+and a color at a given index is compressed, then
+<symbol>True</symbol>
+should be stored at the corresponding index in this array;
+otherwise, the array should not be modified.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+When implementing a gamut compression procedure, consider the following
+rules and assumptions:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The gamut compression procedure can attempt to compress one or multiple
+specifications at a time.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+When called, elements 0 to index - 1 in the color specification
+array can be assumed to fall within the screen's color gamut.
+In addition, these color specifications are already in some device-dependent
+format (typically
+<structname>XcmsRGBi</structname>).
+If any modifications are made to these color specifications,
+they must be in their initial device-dependent format upon return.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+When called, the element in the color specification array specified
+by the index argument contains the color specification outside the
+screen's color gamut encountered by the calling routine.
+In addition, this color specification can be assumed to be in
+<structname>XcmsCIEXYZ</structname>.
+Upon return, this color specification must be in
+<structname>XcmsCIEXYZ</structname>.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+When called, elements from index to ncolors - 1
+in the color specification array may or may not fall within the
+screen's color gamut.
+In addition, these color specifications can be assumed to be in
+<structname>XcmsCIEXYZ</structname>.
+If any modifications are made to these color specifications,
+they must be in
+<structname>XcmsCIEXYZ</structname>
+upon return.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The color specifications passed to the gamut compression procedure
+have already been adjusted to the Screen White Point.
+This means that at this point the color specification's white point
+is the Screen White Point.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If the gamut compression procedure uses a device-independent color space not
+initially accessible for use in the color management system, use
+<function>XcmsAddColorSpace</function>
+to ensure that it is added.
+ </para>
+ </listitem>
+</itemizedlist>
+</sect2>
+<sect2 id="Supplied_Gamut_Compression_Procedures">
+<title>Supplied Gamut Compression Procedures</title>
+<!-- .XS -->
+<!-- (SN Supplied Gamut Compression Procedures -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The following equations are useful in describing gamut compression
+functions:
+<!-- .EQ -->
+delim %%
+<!-- .EN -->
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+%CIELab~Psychometric~Chroma ~=~ sqrt(a_star sup 2 ~+~ b_star sup 2 )%
+
+%CIELab~Psychometric~Hue ~=~ tan sup -1 left [ b_star over a_star right ]%
+
+%CIELuv~Psychometric~Chroma ~=~ sqrt(u_star sup 2 ~+~ v_star sup 2 )%
+
+%CIELuv~Psychometric~Hue ~=~ tan sup -1 left [ v_star over u_star right ]%
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The gamut compression callback procedures provided by Xlib are as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+<function>XcmsCIELabClipL</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+This brings the encountered out-of-gamut color specification into the
+screen's color gamut by reducing or increasing <acronym>CIE</acronym> metric lightness (L*)
+in the <acronym>CIE</acronym> L*a*b* color space until the color is within the gamut.
+If the Psychometric Chroma of the color specification
+is beyond maximum for the Psychometric Hue Angle,
+then while maintaining the same Psychometric Hue Angle,
+the color will be clipped to the <acronym>CIE</acronym> L*a*b* coordinates of maximum
+Psychometric Chroma.
+See
+<function>XcmsCIELabQueryMaxC</function>.
+No client data is necessary.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XcmsCIELabClipab</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+This brings the encountered out-of-gamut color specification into the
+screen's color gamut by reducing Psychometric Chroma,
+while maintaining Psychometric Hue Angle,
+until the color is within the gamut.
+No client data is necessary.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XcmsCIELabClipLab</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+This brings the encountered out-of-gamut color specification into the
+screen's color gamut by replacing it with <acronym>CIE</acronym> L*a*b* coordinates
+that fall within the color gamut while maintaining the original
+Psychometric Hue
+Angle and whose vector to the original coordinates is the shortest attainable.
+No client data is necessary.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XcmsCIELuvClipL</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+This brings the encountered out-of-gamut color specification into the
+screen's color gamut by reducing or increasing <acronym>CIE</acronym> metric lightness (L*)
+in the <acronym>CIE</acronym> L*u*v* color space until the color is within the gamut.
+If the Psychometric Chroma of the color specification
+is beyond maximum for the Psychometric Hue Angle,
+then, while maintaining the same Psychometric Hue Angle,
+the color will be clipped to the <acronym>CIE</acronym> L*u*v* coordinates of maximum
+Psychometric Chroma.
+See
+<function>XcmsCIELuvQueryMaxC</function>.
+No client data is necessary.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XcmsCIELuvClipuv</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+This brings the encountered out-of-gamut color specification into the
+screen's color gamut by reducing
+Psychometric Chroma, while maintaining Psychometric Hue Angle,
+until the color is within the gamut.
+No client data is necessary.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XcmsCIELuvClipLuv</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+This brings the encountered out-of-gamut color specification into the
+screen's color gamut by replacing it with <acronym>CIE</acronym> L*u*v* coordinates
+that fall within the color gamut while maintaining the original
+Psychometric Hue
+Angle and whose vector to the original coordinates is the shortest attainable.
+No client data is necessary.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XcmsTekHVCClipV</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+This brings the encountered out-of-gamut color specification into the
+screen's color gamut by reducing or increasing the Value dimension
+in the TekHVC color space until the color is within the gamut.
+If Chroma of the color specification is beyond maximum for the particular Hue,
+then, while maintaining the same Hue,
+the color will be clipped to the Value and Chroma coordinates
+that represent maximum Chroma for that particular Hue.
+No client data is necessary.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XcmsTekHVCClipC</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+This brings the encountered out-of-gamut color specification into the
+screen's color gamut by reducing the Chroma dimension
+in the TekHVC color space until the color is within the gamut.
+No client data is necessary.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XcmsTekHVCClipVC</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+This brings the encountered out-of-gamut color specification into the
+screen's color gamut by replacing it with TekHVC coordinates
+that fall within the color gamut while maintaining the original Hue
+and whose vector to the original coordinates is the shortest attainable.
+No client data is necessary.
+ </para>
+ </listitem>
+</itemizedlist>
+</sect2>
+<sect2 id="Prototype_White_Point_Adjustment_Procedure">
+<title>Prototype White Point Adjustment Procedure</title>
+<!-- .XS -->
+<!-- (SN Prototype White Point Adjustment Procedure -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The white point adjustment procedure interface must adhere to the following:
+</para>
+<indexterm significance="preferred"><primary>XcmsWhiteAdjustProc</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmswhiteadjustproc'>
+<funcprototype>
+ <funcdef>typedef Status <function>(*XcmsWhiteAdjustProc</function>)</funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *initial_white_point</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *target_white_point</parameter></paramdef>
+ <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> colors_in_out[]</parameter></paramdef>
+ <paramdef>unsignedint<parameter> ncolors</parameter></paramdef>
+ <paramdef>Bool<parameter> compression_flags_return[]</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>initial_white_point</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the initial white point.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>target_white_point</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the target white point.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>target_format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the target color specification format.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colors_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of color specifications.
+Pixel members should be ignored and must remain unchanged upon return.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ncolors</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of
+<structname>XcmsColor</structname>
+structures in the color-specification array.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>compression_flags_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns an array of Boolean values for indicating compression status.
+If a non-NULL pointer is supplied
+and a color at a given index is compressed, then
+<symbol>True</symbol>
+should be stored at the corresponding index in this array;
+otherwise, the array should not be modified.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+</para>
+</sect2>
+<sect2 id="Supplied_White_Point_Adjustment_Procedures">
+<title>Supplied White Point Adjustment Procedures</title>
+<!-- .XS -->
+<!-- (SN Supplied White Point Adjustment Procedures -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+White point adjustment procedures provided by Xlib are as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+<function>XcmsCIELabWhiteShiftColors</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+This uses the <acronym>CIE</acronym> L*a*b* color space for adjusting the chromatic character
+of colors to compensate for the chromatic differences between the source
+and destination white points.
+This procedure simply converts the color specifications to
+<structname>XcmsCIELab</structname>
+using the source white point and then converts to the target specification
+format using the destination's white point.
+No client data is necessary.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XcmsCIELuvWhiteShiftColors</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+This uses the <acronym>CIE</acronym> L*u*v* color space for adjusting the chromatic character
+of colors to compensate for the chromatic differences between the source
+and destination white points.
+This procedure simply converts the color specifications to
+<structname>XcmsCIELuv</structname>
+using the source white point and then converts to the target specification
+format using the destination's white point.
+No client data is necessary.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<function>XcmsTekHVCWhiteShiftColors</function>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+This uses the TekHVC color space for adjusting the chromatic character
+of colors to compensate for the chromatic differences between the source
+and destination white points.
+This procedure simply converts the color specifications to
+<structname>XcmsTekHVC</structname>
+using the source white point and then converts to the target specification
+format using the destination's white point.
+An advantage of this procedure over those previously described
+is an attempt to minimize hue shift.
+No client data is necessary.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+From an implementation point of view,
+these white point adjustment procedures convert the color specifications
+to a device-independent but white-point-dependent color space
+(for example, <acronym>CIE</acronym> L*u*v*, <acronym>CIE</acronym> L*a*b*, TekHVC) using one white point
+and then converting those specifications to the target color space
+using another white point.
+In other words,
+the specification goes in the color space with one white point
+but comes out with another white point,
+resulting in a chromatic shift based on the chromatic displacement
+between the initial white point and target white point.
+The <acronym>CIE</acronym> color spaces that are assumed to be white-point-independent
+are <acronym>CIE</acronym> u'v'Y, <acronym>CIE</acronym> XYZ, and <acronym>CIE</acronym> xyY.
+When developing a custom white point adjustment procedure that uses a
+device-independent color space not initially accessible for use in the
+color management system, use
+<function>XcmsAddColorSpace</function>
+to ensure that it is added.
+</para>
+<para>
+<!-- .LP -->
+As an example,
+if the CCC specifies a white point adjustment procedure
+and if the Client White Point and Screen White Point differ, the
+<function>XcmsAllocColor</function>
+function will use the white point adjustment
+procedure twice:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Once to convert to
+<structname>XcmsRGB</structname>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A second time to convert from
+<structname>XcmsRGB</structname>
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+For example, assume the specification is in
+<structname>XcmsCIEuvY</structname>
+and the adjustment procedure is
+<function>XcmsCIELuvWhiteShiftColors</function>.
+During conversion to
+<structname>XcmsRGB</structname>,
+the call to
+<function>XcmsAllocColor</function>
+results in the following series of color specification conversions:
+<!-- .\" Do these need to be font coded? -->
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+From
+<structname>XcmsCIEuvY</structname>
+to
+<structname>XcmsCIELuv</structname>
+using the Client White Point
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+From
+<structname>XcmsCIELuv</structname>
+to
+<structname>XcmsCIEuvY</structname>
+using the Screen White Point
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+From
+<structname>XcmsCIEuvY</structname>
+to
+<structname>XcmsCIEXYZ</structname>
+(<acronym>CIE</acronym> u'v'Y and XYZ are white-point-independent color spaces)
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+From
+<structname>XcmsCIEXYZ</structname>
+to
+<structname>XcmsRGBi</structname>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+From
+<structname>XcmsRGBi</structname>
+to
+<structname>XcmsRGB</structname>
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The resulting <acronym>RGB</acronym> specification is passed to
+<function>XAllocColor</function>,
+and the <acronym>RGB</acronym>
+specification returned by
+<function>XAllocColor</function>
+is converted back to
+<structname>XcmsCIEuvY</structname>
+by reversing the color conversion sequence.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Gamut_Querying_Functions">
+<title>Gamut Querying Functions</title>
+<!-- .XS -->
+<!-- (SN Gamut Querying Functions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This section describes the gamut querying functions that Xlib provides.
+These functions allow the client to query the boundary
+of the screen's color gamut in terms of the <acronym>CIE</acronym> L*a*b*, <acronym>CIE</acronym> L*u*v*,
+and TekHVC color spaces.
+<indexterm><primary>Gamut querying</primary></indexterm>
+Functions are also provided that allow you to query
+the color specification of:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+White (full-intensity red, green, and blue)
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Red (full-intensity red while green and blue are zero)
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Green (full-intensity green while red and blue are zero)
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Blue (full-intensity blue while red and green are zero)
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Black (zero-intensity red, green, and blue)
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The white point associated with color specifications passed to
+and returned from these gamut querying
+functions is assumed to be the Screen White Point.
+<indexterm><primary>Screen White Point</primary></indexterm>
+This is a reasonable assumption,
+because the client is trying to query the screen's color gamut.
+</para>
+<para>
+<!-- .LP -->
+The following naming convention is used for the Max and Min functions:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+Xcms<emphasis remap='I'>&lt;color_space&gt;</emphasis>QueryMax<emphasis remap='I'>&lt;dimensions&gt;</emphasis>
+
+Xcms<emphasis remap='I'>&lt;color_space&gt;</emphasis>QueryMin<emphasis remap='I'>&lt;dimensions&gt;</emphasis>
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The &lt;dimensions&gt; consists of a letter or letters
+that identify the dimensions of the color space
+that are not fixed.
+For example,
+<function>XcmsTekHVCQueryMaxC</function>
+is given a fixed Hue and Value for which maximum Chroma is found.
+</para>
+<sect2 id="Red_Green_and_Blue_Queries">
+<title>Red, Green, and Blue Queries</title>
+<!-- .XS -->
+<!-- (SN Red, Green, and Blue Queries -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To obtain the color specification for black
+(zero-intensity red, green, and blue), use
+<function>XcmsQueryBlack</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsQueryBlack</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsqueryblack'>
+<funcprototype>
+ <funcdef>Status <function>XcmsQueryBlack</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>target_format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the target color specification format.
+<!-- .ds Cs zero-intensity red, green, and blue -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the color specification in the specified target format
+for (Cs.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsQueryBlack</function>
+function returns the color specification in the specified target format
+for zero-intensity red, green, and blue.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the color specification for blue
+(full-intensity blue while red and green are zero), use
+<function>XcmsQueryBlue</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsQueryBlue</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsqueryblue'>
+<funcprototype>
+ <funcdef>Status <function>XcmsQueryBlue</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>target_format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the target color specification format.
+<!-- .ds Cs full-intensity blue while red and green are zero -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the color specification in the specified target format
+for (Cs.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsQueryBlue</function>
+function returns the color specification in the specified target format
+for full-intensity blue while red and green are zero.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the color specification for green
+(full-intensity green while red and blue are zero), use
+<function>XcmsQueryGreen</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsQueryGreen</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsquerygreen'>
+<funcprototype>
+ <funcdef>Status <function>XcmsQueryGreen</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>target_format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the target color specification format.
+<!-- .ds Cs full-intensity green while red and blue are zero -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the color specification in the specified target format
+for (Cs.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsQueryGreen</function>
+function returns the color specification in the specified target format
+for full-intensity green while red and blue are zero.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the color specification for red
+(full-intensity red while green and blue are zero), use
+<function>XcmsQueryRed</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsQueryRed</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsqueryred'>
+<funcprototype>
+ <funcdef>Status <function>XcmsQueryRed</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>target_format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the target color specification format.
+<!-- .ds Cs full-intensity red while green and blue are zero -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the color specification in the specified target format
+for (Cs.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsQueryRed</function>
+function returns the color specification in the specified target format
+for full-intensity red while green and blue are zero.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the color specification for white
+(full-intensity red, green, and blue), use
+<function>XcmsQueryWhite</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsQueryWhite</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsquerywhite'>
+<funcprototype>
+ <funcdef>Status <function>XcmsQueryWhite</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsColorFormat<parameter> target_format</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>target_format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the target color specification format.
+<!-- .ds Cs full-intensity red, green, and blue -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the color specification in the specified target format
+for (Cs.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsQueryWhite</function>
+function returns the color specification in the specified target format
+for full-intensity red, green, and blue.
+</para>
+</sect2>
+<sect2 id="CIELab_Queries">
+<title>CIELab Queries</title>
+<!-- .XS -->
+<!-- (SN CIELab Queries -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The following equations are useful in describing the CIELab query functions:
+<!-- .EQ -->
+delim %%
+<!-- .EN -->
+</para>
+<para>
+<!-- .LP -->
+<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
+<indexterm><primary>Psychometric Chroma</primary></indexterm>
+<indexterm><primary>Psychometric Chroma</primary><secondary>maximum</secondary></indexterm>
+<literallayout class="monospaced">
+%CIELab~Psychometric~Chroma ~=~ sqrt(a_star sup 2 ~+~ b_star sup 2 )%
+
+%CIELab~Psychometric~Hue ~=~ tan sup -1 left [ b_star over a_star right ]%
+</literallayout>
+<!-- .sp -->
+To obtain the <acronym>CIE</acronym> L*a*b* coordinates of maximum Psychometric Chroma
+for a given Psychometric Hue Angle and <acronym>CIE</acronym> metric lightness (L*), use
+<function>XcmsCIELabQueryMaxC</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsCIELabQueryMaxC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmscielabquerymaxc'>
+<funcprototype>
+ <funcdef>Status <function>XcmsCIELabQueryMaxC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> L_star</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Ha maximum chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue_angle</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the hue angle (in degrees) at which to find (Ha.
+<!-- .ds Ls maximum chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>L_star</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the lightness (L*) at which to find (Ls.
+<!-- .ds Lc maximum chroma -->
+<!-- .ds lC hue angle and lightness -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the <acronym>CIE</acronym> L*a*b* coordinates of (Lc
+displayable by the screen for the given (lC.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsCIELabQueryMaxC</function>
+function, given a hue angle and lightness,
+finds the point of maximum chroma displayable by the screen.
+It returns this point in <acronym>CIE</acronym> L*a*b* coordinates.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the <acronym>CIE</acronym> L*a*b* coordinates of maximum <acronym>CIE</acronym> metric lightness (L*)
+for a given Psychometric Hue Angle and Psychometric Chroma, use
+<function>XcmsCIELabQueryMaxL</function>.
+</para>
+<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary><secondary>maximum</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsCIELabQueryMaxL</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmscielabquerymaxl'>
+<funcprototype>
+ <funcdef>Status <function>XcmsCIELabQueryMaxL</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> chroma</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Ha maximum lightness -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue_angle</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the hue angle (in degrees) at which to find (Ha.
+<!-- .ds Ch maximum lightness -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>chroma</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the chroma at which to find (Ch.
+<!-- .ds Lc maximum lightness -->
+<!-- .ds lC hue angle and chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the <acronym>CIE</acronym> L*a*b* coordinates of (Lc
+displayable by the screen for the given (lC.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsCIELabQueryMaxL</function>
+function, given a hue angle and chroma,
+finds the point in <acronym>CIE</acronym> L*a*b* color space of maximum
+lightness (L*) displayable by the screen.
+It returns this point in <acronym>CIE</acronym> L*a*b* coordinates.
+An
+<symbol>XcmsFailure</symbol>
+return value usually indicates that the given chroma
+is beyond maximum for the given hue angle.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the <acronym>CIE</acronym> L*a*b* coordinates of maximum Psychometric Chroma
+for a given Psychometric Hue Angle, use
+<function>XcmsCIELabQueryMaxLC</function>.
+</para>
+<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
+<indexterm><primary>Psychometric Chroma</primary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
+<indexterm><primary>Psychometric Chroma</primary><secondary>maximum</secondary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary><secondary>maximum</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsCIELabQueryMaxLC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmscielabquerymaxlc'>
+<funcprototype>
+ <funcdef>Status <function>XcmsCIELabQueryMaxLC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Ha maximum chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue_angle</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the hue angle (in degrees) at which to find (Ha.
+<!-- .ds Lc maximum chroma -->
+<!-- .ds lC hue angle -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the <acronym>CIE</acronym> L*a*b* coordinates of (Lc
+displayable by the screen for the given (lC.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsCIELabQueryMaxLC</function>
+function, given a hue angle,
+finds the point of maximum chroma displayable by the screen.
+It returns this point in <acronym>CIE</acronym> L*a*b* coordinates.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the <acronym>CIE</acronym> L*a*b* coordinates of minimum <acronym>CIE</acronym> metric lightness (L*)
+for a given Psychometric Hue Angle and Psychometric Chroma, use
+<function>XcmsCIELabQueryMinL</function>.
+</para>
+<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary><secondary>minimum</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsCIELabQueryMinL</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmscielabqueryminlc'>
+<funcprototype>
+ <funcdef>Status <function>XcmsCIELabQueryMinL</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> chroma</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Ha minimum lightness -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue_angle</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the hue angle (in degrees) at which to find (Ha.
+<!-- .ds Ch minimum lightness -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>chroma</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the chroma at which to find (Ch.
+<!-- .ds Lc minimum lightness -->
+<!-- .ds lC hue angle and chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the <acronym>CIE</acronym> L*a*b* coordinates of (Lc
+displayable by the screen for the given (lC.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsCIELabQueryMinL</function>
+function, given a hue angle and chroma,
+finds the point of minimum lightness (L*) displayable by the screen.
+It returns this point in <acronym>CIE</acronym> L*a*b* coordinates.
+An
+<symbol>XcmsFailure</symbol>
+return value usually indicates that the given chroma
+is beyond maximum for the given hue angle.
+</para>
+</sect2>
+<sect2 id="CIELuv_Queries">
+<title>CIELuv Queries</title>
+<!-- .XS -->
+<!-- (SN CIELuv Queries -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The following equations are useful in describing the CIELuv query functions:
+<!-- .EQ -->
+delim %%
+<!-- .EN -->
+</para>
+<para>
+<!-- .LP -->
+<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
+<indexterm><primary>Psychometric Chroma</primary></indexterm>
+<indexterm><primary>Psychometric Chroma</primary><secondary>maximum</secondary></indexterm>
+<literallayout class="monospaced">
+%CIELuv~Psychometric~Chroma ~=~ sqrt(u_star sup 2 ~+~ v_star sup 2 )%
+
+%CIELuv~Psychometric~Hue ~=~ tan sup -1 left [ v_star over u_star right ]%
+</literallayout>
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the <acronym>CIE</acronym> L*u*v* coordinates of maximum Psychometric Chroma
+for a given Psychometric Hue Angle and <acronym>CIE</acronym> metric lightness (L*), use
+<function>XcmsCIELuvQueryMaxC</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsCIELuvQueryMaxC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmxcieluvquerymaxc'>
+<funcprototype>
+ <funcdef>Status <function>XcmsCIELuvQueryMaxC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> L_star</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Ha maximum chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue_angle</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the hue angle (in degrees) at which to find (Ha.
+<!-- .ds Ls maximum chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>L_star</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the lightness (L*) at which to find (Ls.
+<!-- .ds Lc maximum chroma -->
+<!-- .ds lC hue angle and lightness -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the <acronym>CIE</acronym> L*u*v* coordinates of (Lc
+displayable by the screen for the given (lC.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsCIELuvQueryMaxC</function>
+function, given a hue angle and lightness,
+finds the point of maximum chroma displayable by the screen.
+It returns this point in <acronym>CIE</acronym> L*u*v* coordinates.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the <acronym>CIE</acronym> L*u*v* coordinates of maximum <acronym>CIE</acronym> metric lightness (L*)
+for a given Psychometric Hue Angle and Psychometric Chroma, use
+<function>XcmsCIELuvQueryMaxL</function>.
+</para>
+<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary><secondary>maximum</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsCIELuvQueryMaxL</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmscieluvquerymaxl'>
+<funcprototype>
+ <funcdef>Status <function>XcmsCIELuvQueryMaxL</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> chroma</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Ha maximum lightness -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue_angle</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the hue angle (in degrees) at which to find (Ha.
+<!-- .ds Ls maximum lightness -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>L_star</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the lightness (L*) at which to find (Ls.
+<!-- .ds Lc maximum lightness -->
+<!-- .ds lC hue angle and chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the <acronym>CIE</acronym> L*u*v* coordinates of (Lc
+displayable by the screen for the given (lC.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsCIELuvQueryMaxL</function>
+function, given a hue angle and chroma,
+finds the point in <acronym>CIE</acronym> L*u*v* color space of maximum
+lightness (L*) displayable by the screen.
+It returns this point in <acronym>CIE</acronym> L*u*v* coordinates.
+An
+<symbol>XcmsFailure</symbol>
+return value usually indicates that the given chroma
+is beyond maximum for the given hue angle.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the <acronym>CIE</acronym> L*u*v* coordinates of maximum Psychometric Chroma
+for a given Psychometric Hue Angle, use
+<function>XcmsCIELuvQueryMaxLC</function>.
+</para>
+<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
+<indexterm><primary>Psychometric Chroma</primary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
+<indexterm><primary>Psychometric Chroma</primary><secondary>maximum</secondary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary><secondary>maximum</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsCIELuvQueryMaxLC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmscieluvquerymaxlc'>
+<funcprototype>
+ <funcdef>Status <function>XcmsCIELuvQueryMaxLC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Ha maximum chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue_angle</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the hue angle (in degrees) at which to find (Ha.
+<!-- .ds Lc maximum chroma -->
+<!-- .ds lC hue angle -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the <acronym>CIE</acronym> L*u*v* coordinates of (Lc
+displayable by the screen for the given (lC.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsCIELuvQueryMaxLC</function>
+function, given a hue angle,
+finds the point of maximum chroma displayable by the screen.
+It returns this point in <acronym>CIE</acronym> L*u*v* coordinates.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the <acronym>CIE</acronym> L*u*v* coordinates of minimum <acronym>CIE</acronym> metric lightness (L*)
+for a given Psychometric Hue Angle and Psychometric Chroma, use
+<function>XcmsCIELuvQueryMinL</function>.
+</para>
+<indexterm><primary>Psychometric Hue Angle</primary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary></indexterm>
+<indexterm><primary><acronym>CIE</acronym> metric lightness</primary><secondary>minimum</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsCIELuvQueryMinL</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmscieluvqueryminl'>
+<funcprototype>
+ <funcdef>Status <function>XcmsCIELuvQueryMinL</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue_angle</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> chroma</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Ha minimum lightness -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue_angle</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the hue angle (in degrees) at which to find (Ha.
+<!-- .ds Ch minimum lightness -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>chroma</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the chroma at which to find (Ch.
+<!-- .ds Lc minimum lightness -->
+<!-- .ds lC hue angle and chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the <acronym>CIE</acronym> L*u*v* coordinates of (Lc
+displayable by the screen for the given (lC.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsCIELuvQueryMinL</function>
+function, given a hue angle and chroma,
+finds the point of minimum lightness (L*) displayable by the screen.
+It returns this point in <acronym>CIE</acronym> L*u*v* coordinates.
+An
+<symbol>XcmsFailure</symbol>
+return value usually indicates that the given chroma
+is beyond maximum for the given hue angle.
+</para>
+</sect2>
+<sect2 id="TekHVC_Queries">
+<title>TekHVC Queries</title>
+<!-- .XS -->
+<!-- (SN TekHVC Queries -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To obtain the maximum Chroma for a given Hue and Value, use
+<function>XcmsTekHVCQueryMaxC</function>.
+</para>
+<indexterm><primary>Chroma</primary></indexterm>
+<indexterm><primary>Chroma</primary><secondary>maximum</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsTekHVCQueryMaxC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmstekhvcquerymaxc'>
+<funcprototype>
+ <funcdef>Status <function>XcmsTekHVCQueryMaxC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> value</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Hu in which to find the maximum Chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the Hue (Hu.
+<!-- .ds Va maximum Chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the Value in which to find the (Va.
+<!-- .ds Lc maximum Chroma along with the actual Hue and Value -->
+<!-- .ds lC maximum Chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the (Lc at which the (lC was found.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsTekHVCQueryMaxC</function>
+function, given a Hue and Value,
+determines the maximum Chroma in TekHVC color space
+displayable by the screen.
+It returns the maximum Chroma along with the actual Hue
+and Value at which the maximum Chroma was found.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the maximum Value for a given Hue and Chroma, use
+<function>XcmsTekHVCQueryMaxV</function>.
+</para>
+<indexterm><primary>Value</primary></indexterm>
+<indexterm><primary>Value</primary><secondary>maximum</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsTekHVCQueryMaxV</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmstekhvcquerymaxv'>
+<funcprototype>
+ <funcdef>Status <function>XcmsTekHVCQueryMaxV</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> chroma</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Hu in which to find the maximum Value -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the Hue (Hu.
+<!-- .ds Ch maximum Value -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>chroma</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the chroma at which to find (Ch.
+<!-- .ds Lc maximum Value along with the Hue and Chroma -->
+<!-- .ds lC maximum Value -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the (Lc at which the (lC was found.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsTekHVCQueryMaxV</function>
+function, given a Hue and Chroma,
+determines the maximum Value in TekHVC color space
+displayable by the screen.
+It returns the maximum Value and the actual Hue and Chroma
+at which the maximum Value was found.
+<!-- .sp -->
+</para>
+
+<para>
+<!-- .LP -->
+To obtain the maximum Chroma and Value at which it is reached
+for a specified Hue, use
+<function>XcmsTekHVCQueryMaxVC</function>.
+</para>
+<indexterm><primary>Chroma</primary></indexterm>
+<indexterm><primary>Value</primary></indexterm>
+<indexterm><primary>Chroma</primary><secondary>maximum</secondary></indexterm>
+<indexterm><primary>Value</primary><secondary>maximum</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsTekHVCQueryMaxVC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmstekhvcquerymaxvc'>
+<funcprototype>
+ <funcdef>Status <function>XcmsTekHVCQueryMaxVC</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Hu in which to find the maximum Chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the Hue (Hu.
+<!-- .ds Lc color specification in \ -->
+XcmsTekHVC for the maximum Chroma, the Value at which \
+that maximum Chroma is reached, and the actual Hue
+<!-- .ds lC maximum Chroma -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the (Lc at which the (lC was found.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsTekHVCQueryMaxVC</function>
+function, given a Hue,
+determines the maximum Chroma in TekHVC color space displayable by the screen
+and the Value at which that maximum Chroma is reached.
+It returns the maximum Chroma,
+the Value at which that maximum Chroma is reached,
+and the actual Hue for which the maximum Chroma was found.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain a specified number of TekHVC specifications such that they
+contain maximum Values for a specified Hue and the
+Chroma at which the maximum Values are reached, use
+<function>XcmsTekHVCQueryMaxVSamples</function>.
+</para>
+<indexterm><primary>Chroma</primary></indexterm>
+<indexterm><primary>Value</primary></indexterm>
+<indexterm><primary>Chroma</primary><secondary>maximum</secondary></indexterm>
+<indexterm><primary>Value</primary><secondary>maximum</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsTekHVCQueryMaxVSamples</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmstekhvcquerymaxvsamples'>
+<funcprototype>
+ <funcdef>Status <function>XcmsTekHVCQueryMaxVSamples</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> colors_return[]</parameter></paramdef>
+ <paramdef>unsignedint<parameter> nsamples</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Hu for maximum Chroma/Value samples -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the Hue (Hu.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nsamples</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of samples.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colors_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns nsamples of color specifications in XcmsTekHVC
+such that the Chroma is the maximum attainable for the Value and Hue.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsTekHVCQueryMaxVSamples</function>
+returns nsamples of maximum Value, the Chroma at which that maximum Value
+is reached, and the actual Hue for which the maximum Chroma was found.
+These sample points may then be used to plot the maximum Value/Chroma
+boundary of the screen's color gamut for the specified Hue in TekHVC color
+space.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the minimum Value for a given Hue and Chroma, use
+<function>XcmsTekHVCQueryMinV</function>.
+</para>
+<indexterm><primary>Value</primary></indexterm>
+<indexterm><primary>Value</primary><secondary>minimum</secondary></indexterm>
+<indexterm significance="preferred"><primary>XcmsTekHVCQueryMinV</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmstekhvcqueryminv'>
+<funcprototype>
+ <funcdef>Status <function>XcmsTekHVCQueryMinV</function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> hue</parameter></paramdef>
+ <paramdef>XcmsFloat<parameter> chroma</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+The CCC's Client White Point and white point adjustment procedures
+are ignored.
+<!-- .ds Hu in which to find the minimum Value -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hue</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the Hue (Hu.
+<!-- .ds Va minimum Value -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the Value in which to find the (Va.
+<!-- .ds Lc minimum Value and the actual Hue and Chroma -->
+<!-- .ds lC minimum Value -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the (Lc at which the (lC was found.
+The white point associated with the returned
+color specification is the Screen White Point.
+The value returned in the pixel member is undefined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsTekHVCQueryMinV</function>
+function, given a Hue and Chroma,
+determines the minimum Value in TekHVC color space displayable by the screen.
+It returns the minimum Value and the actual Hue and Chroma at which
+the minimum Value was found.
+</para>
+
+</sect2>
+</sect1>
+<sect1 id="Color_Management_Extensions">
+<title>Color Management Extensions</title>
+<!-- .XS -->
+<!-- (SN Color Management Extensions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The Xlib color management facilities can be extended in two ways:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Device-Independent Color Spaces
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Device-independent color spaces that are derivable to <acronym>CIE</acronym> XYZ
+space can be added using the
+<function>XcmsAddColorSpace</function>
+function.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Color Characterization Function Set
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A Color Characterization Function Set consists of
+device-dependent color spaces and their functions that
+convert between these color spaces and the <acronym>CIE</acronym> XYZ
+color space, bundled together for a specific class of output devices.
+A function set can be added using the
+<function>XcmsAddFunctionSet</function>
+function.
+ </para>
+ </listitem>
+</itemizedlist>
+<sect2 id="Color_Spaces">
+<title>Color Spaces</title>
+<!-- .XS -->
+<!-- (SN Color Spaces -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The <acronym>CIE</acronym> XYZ color space serves as the hub for all
+conversions between device-independent and device-dependent color spaces.
+Therefore, the knowledge to convert an
+<structname>XcmsColor</structname>
+structure to and from <acronym>CIE</acronym> XYZ format is associated with each color space.
+For example, conversion from <acronym>CIE</acronym> L*u*v* to <acronym>RGB</acronym> requires the knowledge
+to convert from <acronym>CIE</acronym> L*u*v* to <acronym>CIE</acronym> XYZ and from <acronym>CIE</acronym> XYZ to <acronym>RGB</acronym>.
+This knowledge is stored as an array of functions that,
+when applied in series, will convert the
+<structname>XcmsColor</structname>
+structure to or from <acronym>CIE</acronym> XYZ format.
+This color specification conversion mechanism facilitates
+the addition of color spaces.
+</para>
+<para>
+<!-- .LP -->
+Of course, when converting between only device-independent color spaces
+or only device-dependent color spaces,
+shortcuts are taken whenever possible.
+For example, conversion from TekHVC to <acronym>CIE</acronym> L*u*v* is performed
+by intermediate conversion to <acronym>CIE</acronym> u*v*Y and then to <acronym>CIE</acronym> L*u*v*,
+thus bypassing conversion between <acronym>CIE</acronym> u*v*Y and <acronym>CIE</acronym> XYZ.
+</para>
+</sect2>
+<sect2 id="Adding_Device_Independent_Color_Spaces">
+<title>Adding Device-Independent Color Spaces</title>
+<!-- .XS -->
+<!-- (SN Adding Device-Independent Color Spaces -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To add a device-independent color space, use
+<function>XcmsAddColorSpace</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsAddColorSpace</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsaddcolorspace'>
+<funcprototype>
+ <funcdef>Status <function>XcmsAddColorSpace</function></funcdef>
+ <paramdef>XcmsColorSpace<parameter> *color_space</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_space</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the device-independent color space to add.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsAddColorSpace</function>
+function makes a device-independent color space (actually an
+<structname>XcmsColorSpace</structname>
+structure) accessible by the color management system.
+Because format values for unregistered color spaces are assigned at run time,
+they should be treated as private to the client.
+If references to an unregistered color space must be made
+outside the client (for example, storing color specifications
+in a file using the unregistered color space),
+then reference should be made by color space prefix
+(see
+<function>XcmsFormatOfPrefix</function>
+and
+<function>XcmsPrefixOfFormat</function>).
+</para>
+<para>
+<!-- .LP -->
+If the
+<structname>XcmsColorSpace</structname>
+structure is already accessible in the color management system,
+<function>XcmsAddColorSpace</function>
+returns
+<symbol>XcmsSuccess</symbol>.
+</para>
+<para>
+<!-- .LP -->
+Note that added
+<structname>XcmsColorSpace</structname>s
+must be retained for reference by Xlib.
+</para>
+</sect2>
+<sect2 id="Querying_Color_Space_Format_and_Prefix">
+<title>Querying Color Space Format and Prefix</title>
+<!-- .XS -->
+<!-- (SN Querying Color Space Format and Prefix -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To obtain the format associated with the color space
+associated with a specified color string prefix, use
+<function>XcmsFormatOfPrefix</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsFormatOfPrefix</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsformatofprefix'>
+<funcprototype>
+ <funcdef>XcmsColorFormat <function>XcmsFormatOfPrefix</function></funcdef>
+ <paramdef>char<parameter> *prefix</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>prefix</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the string that contains the color space prefix.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsFormatOfPrefix</function>
+function returns the format for the specified color space prefix
+(for example, the string ``CIEXYZ'').
+The prefix is case-insensitive.
+If the color space is not accessible in the color management system,
+<function>XcmsFormatOfPrefix</function>
+returns
+<symbol>XcmsUndefinedFormat</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the color string prefix associated with the color space
+specified by a color format, use
+<function>XcmsPrefixOfFormat</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsPrefixOfFormat</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsprefixofformat'>
+<funcprototype>
+ <funcdef>char *<function>XcmsPrefixOfFormat</function></funcdef>
+ <paramdef>XcmsColorFormat<parameter> format</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color specification format.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsPrefixOfFormat</function>
+function returns the string prefix associated with the color specification
+encoding specified by the format argument.
+Otherwise, if no encoding is found, it returns NULL.
+The returned string must be treated as read-only.
+</para>
+</sect2>
+<sect2 id="Creating_Additional_Color_Spaces">
+<title>Creating Additional Color Spaces</title>
+<!-- .XS -->
+<!-- (SN Creating Additional Color Spaces -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Color space specific information necessary
+for color space conversion and color string parsing is stored in an
+<structname>XcmsColorSpace</structname>
+structure.
+Therefore, a new structure containing this information is required
+for each additional color space.
+In the case of device-independent color spaces,
+a handle to this new structure (that is, by means of a global variable)
+is usually made accessible to the client program for use with the
+<function>XcmsAddColorSpace</function>
+function.
+</para>
+<para>
+<!-- .LP -->
+If a new
+<structname>XcmsColorSpace</structname>
+structure specifies a color space not registered with the X Consortium,
+they should be treated as private to the client
+because format values for unregistered color spaces are assigned at run time.
+If references to an unregistered color space must be made outside the
+client (for example, storing color specifications in a file using the
+unregistered color space), then reference should be made by color space prefix
+(see
+<function>XcmsFormatOfPrefix</function>
+and
+<function>XcmsPrefixOfFormat</function>).
+<!-- .sM -->
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef (*XcmsConversionProc)();
+typedef XcmsConversionProc *XcmsFuncListPtr;
+ /* A NULL terminated list of function pointers*/
+
+typedef struct _XcmsColorSpace {
+ char *prefix;
+ XcmsColorFormat format;
+ XcmsParseStringProc parseString;
+ XcmsFuncListPtr to_CIEXYZ;
+ XcmsFuncListPtr from_CIEXYZ;
+ int inverse_flag;
+} XcmsColorSpace;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The prefix member specifies the prefix that indicates a color string
+is in this color space's string format.
+For example, the strings ``ciexyz'' or ``CIEXYZ'' for <acronym>CIE</acronym> XYZ,
+and ``rgb'' or ``<acronym>RGB</acronym>'' for <acronym>RGB</acronym>.
+The prefix is case insensitive.
+The format member specifies the color specification format.
+Formats for unregistered color spaces are assigned at run time.
+The parseString member contains a pointer to the function
+that can parse a color string into an
+<structname>XcmsColor</structname>
+structure.
+This function returns an integer (int): nonzero if it succeeded
+and zero otherwise.
+The to_CIEXYZ and from_CIEXYZ members contain pointers,
+each to a NULL terminated list of function pointers.
+When the list of functions is executed in series,
+it will convert the color specified in an
+<structname>XcmsColor</structname>
+structure from/to the current color space format to/from the <acronym>CIE</acronym> XYZ format.
+Each function returns an integer (int): nonzero if it succeeded
+and zero otherwise.
+The white point to be associated with the colors is specified
+explicitly, even though white points can be found in the CCC.
+The inverse_flag member, if nonzero, specifies that for each function listed
+in to_CIEXYZ,
+its inverse function can be found in from_CIEXYZ such that:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+Given: n = number of functions in each list
+
+for each i, such that 0 &lt;= i &lt; n
+ from_CIEXYZ[n - i - 1] is the inverse of to_CIEXYZ[i].
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+This allows Xlib to use the shortest conversion path,
+thus bypassing <acronym>CIE</acronym> XYZ if possible (for example, TekHVC to <acronym>CIE</acronym> L*u*v*).
+</para>
+</sect2>
+<sect2 id="Parse_String_Callback">
+<title>Parse String Callback</title>
+<!-- .XS -->
+<!-- (SN Parse String Callback -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The callback in the
+<structname>XcmsColorSpace</structname>
+structure for parsing a color string for the particular color space must
+adhere to the following software interface specification:
+</para>
+<indexterm significance="preferred"><primary>XcmsParseStringProc</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsparsestringproc'>
+<funcprototype>
+ <funcdef>Status <function>XcmsParseStringProc</function></funcdef>
+ <paramdef>char<parameter> *color_string</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *color_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the color string to parse.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>color_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the color specification in the color space's format.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+</para>
+</sect2>
+<sect2 id="Color_Specification_Conversion_Callback">
+<title>Color Specification Conversion Callback</title>
+<!-- .XS -->
+<!-- (SN Color Specification Conversion Callback -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Callback functions in the
+<structname>XcmsColorSpace</structname>
+structure for converting a color specification between device-independent
+spaces must adhere to the
+following software interface specification:
+</para>
+<!-- .sM -->
+<funcsynopsis id='conversionproc'>
+<funcprototype>
+ <funcdef>Status <function><replaceable>ConversionProc</replaceable></function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *white_point</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *colors_in_out</parameter></paramdef>
+ <paramdef>unsignedint<parameter> ncolors</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>white_point</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the white point associated with color specifications.
+The pixel member should be ignored,
+and the entire structure remain unchanged upon return.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colors_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of color specifications.
+Pixel members should be ignored and must remain unchanged upon return.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ncolors</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of
+<structname>XcmsColor</structname>
+structures in the color-specification array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+Callback functions in the
+<structname>XcmsColorSpace</structname>
+structure for converting a color specification to or from a device-dependent
+space must adhere to the
+following software interface specification:
+</para>
+<!-- .sM -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>Status <function><replaceable>ConversionProc</replaceable></function></funcdef>
+ <paramdef>XcmsCCC<parameter> ccc</parameter></paramdef>
+ <paramdef>XcmsColor<parameter> *colors_in_out</parameter></paramdef>
+ <paramdef>unsignedint<parameter> ncolors</parameter></paramdef>
+ <paramdef>Bool<parameter> compression_flags_return[]</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ccc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the CCC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colors_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of color specifications.
+Pixel members should be ignored and must remain unchanged upon return.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ncolors</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of
+<structname>XcmsColor</structname>
+structures in the color-specification array.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>compression_flags_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns an array of Boolean values for indicating compression status.
+If a non-NULL pointer is supplied
+and a color at a given index is compressed, then
+<symbol>True</symbol>
+should be stored at the corresponding index in this array;
+otherwise, the array should not be modified.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Conversion functions are available globally for use by other color
+spaces.
+The conversion functions provided by Xlib are:
+</para>
+<informaltable>
+ <tgroup cols='3' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <colspec colname='c3'/>
+ <thead>
+ <row>
+ <entry>Function</entry>
+ <entry>Converts from</entry>
+ <entry>Converts to</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><function>XcmsCIELabToCIEXYZ</function></entry>
+ <entry><symbol>XcmsCIELabFormat</symbol></entry>
+ <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsCIELuvToCIEuvY</function></entry>
+ <entry><symbol>XcmsCIELuvFormat</symbol></entry>
+ <entry><symbol>XcmsCIEuvYFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsCIEXYZToCIELab</function></entry>
+ <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
+ <entry><symbol>XcmsCIELabFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsCIEXYZToCIEuvY</function></entry>
+ <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
+ <entry><symbol>XcmsCIEuvYFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsCIEXYZToCIExyY</function></entry>
+ <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
+ <entry><symbol>XcmsCIExyYFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsCIEXYZToRGBi</function></entry>
+ <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
+ <entry><symbol>XcmsRGBiFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsCIEuvYToCIELuv</function></entry>
+ <entry><symbol>XcmsCIEuvYFormat</symbol></entry>
+ <entry><symbol>XcmsCIELabFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsCIEuvYToCIEXYZ</function></entry>
+ <entry><symbol>XcmsCIEuvYFormat</symbol></entry>
+ <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsCIEuvYToTekHVC</function></entry>
+ <entry><symbol>XcmsCIEuvYFormat</symbol></entry>
+ <entry><symbol>XcmsTekHVCFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsCIExyYToCIEXYZ</function></entry>
+ <entry><symbol>XcmsCIExyYFormat</symbol></entry>
+ <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsRGBToRGBi</function></entry>
+ <entry><symbol>XcmsRGBFormat</symbol></entry>
+ <entry><symbol>XcmsRGBiFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsRGBiToCIEXYZ</function></entry>
+ <entry><symbol>XcmsRGBiFormat</symbol></entry>
+ <entry><symbol>XcmsCIEXYZFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsRGBiToRGB</function></entry>
+ <entry><symbol>XcmsRGBiFormat</symbol></entry>
+ <entry><symbol>XcmsRGBFormat</symbol></entry>
+ </row>
+ <row>
+ <entry><function>XcmsTekHVCToCIEuvY</function></entry>
+ <entry><symbol>XcmsTekHVCFormat</symbol></entry>
+ <entry><symbol>XcmsCIEuvYFormat</symbol></entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+</sect2>
+<sect2 id="Function_Sets">
+<title>Function Sets</title>
+<!-- .XS -->
+<!-- (SN Function Sets -->
+<!-- .XE -->
+<indexterm><primary>Function set</primary></indexterm>
+<indexterm><primary>Function set</primary><secondary>LINEAR_RGB</secondary></indexterm>
+<para>
+<!-- .LP -->
+Functions to convert between device-dependent color spaces
+and <acronym>CIE</acronym> XYZ may differ for different classes of output devices
+(for example, color versus gray monitors).
+Therefore, the notion of a Color Characterization Function Set
+has been developed.
+A function set consists of device-dependent color spaces
+and the functions that convert color specifications
+between these device-dependent color spaces and the <acronym>CIE</acronym> XYZ color space
+appropriate for a particular class of output devices.
+The function set also contains a function that reads
+color characterization data off root window properties.
+It is this characterization data that will differ between devices within
+a class of output devices.
+<indexterm><primary>Device Color Characterization</primary></indexterm>
+For details about how color characterization data is
+stored in root window properties,
+see the section on Device Color Characterization in the
+<emphasis remap='I'>Inter-Client Communication Conventions Manual</emphasis>.
+The LINEAR_RGB function set is provided by Xlib
+and will support most color monitors.
+Function sets may require data that differs
+from those needed for the LINEAR_RGB function set.
+In that case,
+its corresponding data may be stored on different root window properties.
+</para>
+</sect2>
+<sect2 id="Adding_Function_Sets">
+<title>Adding Function Sets</title>
+<!-- .XS -->
+<!-- (SN Adding Function Sets -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To add a function set, use
+<function>XcmsAddFunctionSet</function>.
+</para>
+<indexterm significance="preferred"><primary>XcmsAddFunctionSet</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcmsaddfunctionset'>
+<funcprototype>
+ <funcdef>Status <function>XcmsAddFunctionSet</function></funcdef>
+ <paramdef>XcmsFunctionSet<parameter> *function_set</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>function_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the function set to add.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XcmsAddFunctionSet</function>
+function adds a function set to the color management system.
+If the function set uses device-dependent
+<structname>XcmsColorSpace</structname>
+structures not accessible in the color management system,
+<function>XcmsAddFunctionSet</function>
+adds them.
+If an added
+<structname>XcmsColorSpace</structname>
+structure is for a device-dependent color space not registered
+with the X Consortium,
+they should be treated as private to the client
+because format values for unregistered color spaces are assigned at run time.
+If references to an unregistered color space must be made outside the
+client (for example, storing color specifications in a file
+using the unregistered color space),
+then reference should be made by color space prefix
+(see
+<function>XcmsFormatOfPrefix</function>
+and
+<function>XcmsPrefixOfFormat</function>).
+</para>
+<para>
+<!-- .LP -->
+Additional function sets should be added before any calls to other
+Xlib routines are made.
+If not, the
+<structname>XcmsPerScrnInfo</structname>
+member of a previously created
+<structname>XcmsCCC</structname>
+does not have the opportunity to initialize
+with the added function set.
+</para>
+</sect2>
+<sect2 id="Creating_Additional_Function_Sets">
+<title>Creating Additional Function Sets</title>
+<!-- .XS -->
+<!-- (SN Creating Additional Function Sets -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The creation of additional function sets should be
+required only when an output device does not conform to existing
+function sets or when additional device-dependent color spaces are necessary.
+A function set consists primarily of a collection of device-dependent
+<structname>XcmsColorSpace</structname>
+structures and a means to read and store a
+screen's color characterization data.
+This data is stored in an
+<structname>XcmsFunctionSet</structname>
+structure.
+A handle to this structure (that is, by means of global variable)
+is usually made accessible to the client program for use with
+<function>XcmsAddFunctionSet</function>.
+</para>
+<para>
+<!-- .LP -->
+If a function set uses new device-dependent
+<structname>XcmsColorSpace</structname>
+structures,
+they will be transparently processed into the color management system.
+Function sets can share an
+<structname>XcmsColorSpace</structname>
+structure for a device-dependent color space.
+In addition, multiple
+<structname>XcmsColorSpace</structname>
+structures are allowed for a device-dependent color space;
+however, a function set can reference only one of them.
+These
+<structname>XcmsColorSpace</structname>
+structures will differ in the functions to convert to and from <acronym>CIE</acronym> XYZ,
+thus tailored for the specific function set.
+<!-- .sM -->
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct _XcmsFunctionSet {
+ XcmsColorSpace **DDColorSpaces;
+ XcmsScreenInitProc screenInitProc;
+ XcmsScreenFreeProc screenFreeProc;
+} XcmsFunctionSet;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The DDColorSpaces member is a pointer to a NULL terminated list
+of pointers to
+<structname>XcmsColorSpace</structname>
+structures for the device-dependent color spaces that are supported
+by the function set.
+The screenInitProc member is set to the callback procedure (see the following
+interface specification) that initializes the
+<structname>XcmsPerScrnInfo</structname>
+structure for a particular screen.
+</para>
+<para>
+<!-- .LP -->
+The screen initialization callback must adhere to the following software
+interface specification:
+<indexterm significance="preferred"><primary>XcmsScreenInitProc</primary></indexterm>
+<!-- .sM -->
+</para>
+<funcsynopsis>
+<funcprototype>
+ <funcdef>typedef Status <function>(*XcmsScreenInitProc</function>)</funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> screen_number</parameter></paramdef>
+ <paramdef>ScmsPerScrnInfo<parameter> *screen_info</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen_number</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the appropriate screen number on the host server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen_info</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XcmsPerScrnInfo</structname>
+structure, which contains the per screen information.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The screen initialization callback in the
+<structname>XcmsFunctionSet</structname>
+structure fetches the color characterization data (device profile) for
+the specified screen,
+typically off properties on the
+screen's root window.
+It then initializes the specified
+<structname>XcmsPerScrnInfo</structname>
+structure.
+<indexterm><primary>Device profile</primary></indexterm>
+<indexterm><primary>Color Characterization Data</primary></indexterm>
+If successful, the procedure fills in the
+<structname>XcmsPerScrnInfo</structname>
+structure as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+It sets the screenData member to the address
+of the created device profile data structure
+(contents known only by the function set).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+It next sets the screenWhitePoint member.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+It next sets the functionSet member to the address of the
+<structname>XcmsFunctionSet</structname>
+structure.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+It then sets the state member to
+<symbol>XcmsInitSuccess</symbol>
+and finally returns
+<symbol>XcmsSuccess</symbol>.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+If unsuccessful, the procedure sets the state member to
+<symbol>XcmsInitFailure</symbol>
+and returns
+<symbol>XcmsFailure</symbol>.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XcmsPerScrnInfo</structname>
+structure contains:
+<!-- .sM -->
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct _XcmsPerScrnInfo {
+ XcmsColor screenWhitePoint;
+ XPointer functionSet;
+ XPointer screenData;
+ unsigned char state;
+ char pad[3];
+} XcmsPerScrnInfo;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The screenWhitePoint member specifies the white point inherent to
+the screen.
+The functionSet member specifies the appropriate function set.
+The screenData member specifies the device profile.
+The state member is set to one of the following:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+<symbol>XcmsInitNone</symbol>
+indicates initialization has not been previously attempted.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<symbol>XcmsInitFailure</symbol>
+indicates initialization has been previously attempted but failed.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<symbol>XcmsInitSuccess</symbol>
+indicates initialization has been previously attempted and succeeded.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The screen free callback must adhere to the following software
+interface specification:
+</para>
+<funcsynopsis>
+<funcprototype>
+ <funcdef>typedef void (*XcmsScreenFreeProc)</funcdef>
+ <paramdef>XPointer<parameter> screenData</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screenData</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the data to be freed.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+This function is called to free the screenData stored in an
+<structname>XcmsPerScrnInfo</structname>
+structure.
+<!-- .bp -->
+
+</para>
+</sect2>
+</sect1>
+</chapter>
diff --git a/libX11/specs/libX11/CH07.xml b/libX11/specs/libX11/CH07.xml
index 505a565a2..ff1a9d836 100644
--- a/libX11/specs/libX11/CH07.xml
+++ b/libX11/specs/libX11/CH07.xml
@@ -1,3407 +1,3407 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<chapter id="graphics_context_functions">
-<title>Graphics Context Functions</title>
-
-<para>
-A number of resources are used when performing graphics operations in X. Most information
-about performing graphics (for example, foreground color, background color, line style, and so
-on) is stored in resources called graphics contexts (GCs). Most graphics operations (see chapter
-8) take a GC as an argument. Although in theory the X protocol permits sharing of GCs between
-applications, it is expected that applications will use their own GCs when performing operations.
-Sharing of GCs is highly discouraged because the library may cache GC state.
-</para>
-<para>
-Graphics operations can be performed to either windows or pixmaps, which collectively are
-called drawables. Each drawable exists on a single screen. A GC is created for a specific screen
-and drawable depth and can only be used with drawables of matching screen and depth.
-</para>
-<para>
-This chapter discusses how to:
-</para>
-<itemizedlist>
- <listitem><para>Manipulate graphics context/state</para></listitem>
- <listitem><para>Use graphics context convenience functions</para></listitem>
-</itemizedlist>
-
-<sect1 id="Manipulating_Graphics_Context_State">
-<title>Manipulating Graphics Context/State</title>
-<!-- .XS -->
-<!-- (SN Manipulating Graphics Context/State -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Most attributes of graphics operations are stored in GCs.
-These include line width, line style, plane mask, foreground, background,
-tile, stipple, clipping region, end style, join style, and so on.
-Graphics operations (for example, drawing lines) use these values
-to determine the actual drawing operation.
-Extensions to X may add additional components to GCs.
-The contents of a GC are private to Xlib.
-</para>
-<para>
-<!-- .LP -->
-Xlib implements a write-back cache for all elements of a GC that are not
-resource IDs to allow Xlib to implement the transparent coalescing of changes
-to GCs.
-For example,
-a call to
-<function>XSetForeground</function>
-of a GC followed by a call to
-<function>XSetLineAttributes</function>
-results in only a single-change GC protocol request to the server.
-GCs are neither expected nor encouraged to be shared between client
-applications, so this write-back caching should present no problems.
-Applications cannot share GCs without external synchronization.
-Therefore,
-sharing GCs between applications is highly discouraged.
-</para>
-<para>
-<!-- .LP -->
-To set an attribute of a GC,
-set the appropriate member of the
-<structname>XGCValues</structname>
-structure and OR in the corresponding value bitmask in your subsequent calls to
-<function>XCreateGC</function>.
-The symbols for the value mask bits and the
-<structname>XGCValues</structname>
-structure are:
-<!-- .sM -->
-</para>
-
-
-<literallayout class="monospaced">
-/* GC attribute value mask bits */
-
-#define GCFunction (1L&lt;&lt;0)
-#define GCPlaneMask (1L&lt;&lt;1)
-#define GCForeground (1L&lt;&lt;2)
-#define GCBackground (1L&lt;&lt;3)
-#define GCLineWidth (1L&lt;&lt;4)
-#define GCLineStyle (1L&lt;&lt;5)
-#define GCCapStyle (1L&lt;&lt;6)
-#define GCJoinStyle (1L&lt;&lt;7)
-#define GCFillStyle (1L&lt;&lt;8)
-#define GCFillRule (1L&lt;&lt;9)
-#define GCTile (1L&lt;&lt;10)
-#define GCStipple (1L&lt;&lt;11)
-#define GCTileStipXOrigin (1L&lt;&lt;12)
-#define GCTileStipYOrigin (1L&lt;&lt;13)
-#define GCFont (1L&lt;&lt;14)
-#define GCSubwindowMode (1L&lt;&lt;15)
-#define GCGraphicsExposures (1L&lt;&lt;16)
-#define GCClipXOrigin (1L&lt;&lt;17)
-#define GCClipYOrigin (1L&lt;&lt;18)
-#define GCClipMask (1L&lt;&lt;19)
-#define GCDashOffset (1L&lt;&lt;20)
-#define GCDashList (1L&lt;&lt;21)
-#define GCArcMode (1L&lt;&lt;22)
-</literallayout>
-
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-/* Values */
-
-typedef struct {
- int function; /* logical operation */
- unsigned long plane_mask; /* plane mask */
- unsigned long foreground; /* foreground pixel */
- unsigned long background; /* background pixel */
- int line_width; /* line width (in pixels) */
- int line_style; /* LineSolid, LineOnOffDash, LineDoubleDash */
- int cap_style; /* CapNotLast, CapButt, CapRound, CapProjecting */
- int join_style; /* JoinMiter, JoinRound, JoinBevel */
- int fill_style; /* FillSolid, FillTiled, FillStippled FillOpaqueStippled*/
- int fill_rule; /* EvenOddRule, WindingRule */
- int arc_mode; /* ArcChord, ArcPieSlice */
- Pixmap tile; /* tile pixmap for tiling operations */
- Pixmap stipple; /* stipple 1 plane pixmap for stippling */
- int ts_x_origin; /* offset for tile or stipple operations */
- int ts_y_origin
- Font font; /* default text font for text operations */
- int subwindow_mode; /* ClipByChildren, IncludeInferiors */
- Bool graphics_exposures; /* boolean, should exposures be generated */
- int clip_x_origin; /* origin for clipping */
- int clip_y_origin;
- Pixmap clip_mask; /* bitmap clipping; other calls for rects */
- int dash_offset; /* patterned/dashed line information */
- char dashes;
-} XGCValues;
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The default GC values are:
-</para>
-<informaltable>
- <tgroup cols='3' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <thead>
- <row>
- <entry>Component</entry>
- <entry>Default</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry>function</entry>
- <entry><symbol>GXcopy</symbol></entry>
- </row>
- <row>
- <entry>plane_mask</entry>
- <entry>All ones</entry>
- </row>
- <row>
- <entry>foreground</entry>
- <entry>0</entry>
- </row>
- <row>
- <entry>background</entry>
- <entry>1</entry>
- </row>
- <row>
- <entry>line_width</entry>
- <entry>0</entry>
- </row>
- <row>
- <entry>line_style</entry>
- <entry><symbol>LineSolid</symbol></entry>
- </row>
- <row>
- <entry>cap_style</entry>
- <entry><symbol>CapButt</symbol></entry>
- </row>
- <row>
- <entry>join_style</entry>
- <entry><symbol>JoinMiter</symbol></entry>
- </row>
- <row>
- <entry>fill_style</entry>
- <entry><symbol>FillSolid</symbol></entry>
- </row>
- <row>
- <entry>fill_rule</entry>
- <entry><symbol>EvenOddRule</symbol></entry>
- </row>
- <row>
- <entry>arc_mode</entry>
- <entry><symbol>ArcPieSlice</symbol></entry>
- </row>
- <row>
- <entry>tile</entry>
- <entry>Pixmap of unspecified size filled with foreground pixel</entry>
- </row>
- <row>
- <entry></entry>
- <entry>(that is, client specified pixel if any, else 0)</entry>
- </row>
- <row>
- <entry></entry>
- <entry>(subsequent changes to foreground do not affect this pixmap)</entry>
- </row>
- <row>
- <entry>stipple</entry>
- <entry>Pixmap of unspecified size filled with ones</entry>
- </row>
- <row>
- <entry>ts_x_origin</entry>
- <entry>0</entry>
- </row>
- <row>
- <entry>ts_y_origin</entry>
- <entry>0</entry>
- </row>
- <row>
- <entry>font</entry>
- <entry>&lt;implementation dependent&gt;</entry>
- </row>
- <row>
- <entry>subwindow_mode</entry>
- <entry><symbol>ClipByChildren</symbol></entry>
- </row>
- <row>
- <entry>graphics_exposures</entry>
- <entry><symbol>True</symbol></entry>
- </row>
- <row>
- <entry>clip_x_origin</entry>
- <entry>0</entry>
- </row>
- <row>
- <entry>clip_y_origin</entry>
- <entry>0</entry>
- </row>
- <row>
- <entry>clip_mask</entry>
- <entry><symbol>None</symbol></entry>
- </row>
- <row>
- <entry>dash_offset</entry>
- <entry>0</entry>
- </row>
- <row>
- <entry>dashes</entry>
- <entry>4 (that is, the list [4, 4])</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-Note that foreground and background are not set to any values likely
-to be useful in a window.
-</para>
-
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>Display Functions</primary></indexterm>
-<indexterm significance="preferred"><primary>Source</primary></indexterm>
-<indexterm significance="preferred"><primary>Destination</primary></indexterm>
-The function attributes of a GC are used when you update a section of
-a drawable (the destination) with bits from somewhere else (the source).
-The function in a GC defines how the new destination bits are to be
-computed from the source bits and the old destination bits.
-<symbol>GXcopy</symbol>
-is typically the most useful because it will work on a color display,
-but special applications may use other functions,
-particularly in concert with particular planes of a color display.
-The 16 GC functions, defined in
-<filename class="headerfile">&lt;X11/X.h&gt;</filename>,
-<indexterm type="file"><primary><filename class="headerfile">X11/X.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/X.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/X.h&gt;</filename></secondary></indexterm>
-are:
-</para>
-<!-- .\" are listed in Table 5-1 along with the -->
-<!-- .\"the associated hexadecimal code -->
-<!-- .\" and operation. -->
-<!-- .\".CP T 1 -->
-<!-- .\"Display Functions -->
-<informaltable>
- <tgroup cols='3' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <thead>
- <row>
- <entry>Function Name</entry>
- <entry>Value</entry>
- <entry>Operation</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry><symbol>GXclear</symbol></entry>
- <entry>0x0</entry>
- <entry>0</entry>
- </row>
- <row>
- <entry><symbol>GXand</symbol></entry>
- <entry>0x1</entry>
- <entry>src AND dst</entry>
- </row>
- <row>
- <entry><symbol>GXandReverse</symbol></entry>
- <entry>0x2</entry>
- <entry>src AND NOT dst</entry>
- </row>
- <row>
- <entry><symbol>GXcopy</symbol></entry>
- <entry>0x3</entry>
- <entry>src</entry>
- </row>
- <row>
- <entry><symbol>GXandInverted</symbol></entry>
- <entry>0x4</entry>
- <entry>(NOT src) AND dst</entry>
- </row>
- <row>
- <entry><symbol>GXnoop</symbol></entry>
- <entry>0x5</entry>
- <entry>dst</entry>
- </row>
- <row>
- <entry><symbol>GXxor</symbol></entry>
- <entry>0x6</entry>
- <entry>src XOR dst</entry>
- </row>
- <row>
- <entry><symbol>GXor</symbol></entry>
- <entry>0x7</entry>
- <entry>src OR dst</entry>
- </row>
- <row>
- <entry><symbol>GXnor</symbol></entry>
- <entry>0x8</entry>
- <entry>(NOT src) AND (NOT dst)</entry>
- </row>
- <row>
- <entry><symbol>GXequiv</symbol></entry>
- <entry>0x9</entry>
- <entry>(NOT src) XOR dst</entry>
- </row>
- <row>
- <entry><symbol>GXinvert</symbol></entry>
- <entry>0xa</entry>
- <entry>NOT dst</entry>
- </row>
- <row>
- <entry><symbol>GXorReverse</symbol></entry>
- <entry>0xb</entry>
- <entry>src OR (NOT dst)</entry>
- </row>
- <row>
- <entry><symbol>GXcopyInverted</symbol></entry>
- <entry>0xc</entry>
- <entry>NOT src</entry>
- </row>
- <row>
- <entry><symbol>GXorInverted</symbol></entry>
- <entry>0xd</entry>
- <entry>(NOT src) OR dst</entry>
- </row>
- <row>
- <entry><symbol>GXnand</symbol></entry>
- <entry>0xe</entry>
- <entry>(NOT src) OR (NOT dst)</entry>
- </row>
- <row>
- <entry><symbol>GXset</symbol></entry>
- <entry>0xf</entry>
- <entry>1</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-Many graphics operations depend on either pixel values or planes in a GC.
-<indexterm><primary>Pixel value</primary></indexterm>
-The planes attribute is of type long, and it specifies which planes of the
-destination are to be modified, one bit per plane.
-<indexterm><primary>Plane</primary><secondary>mask</secondary></indexterm>
-A monochrome display has only one plane and
-will be the least significant bit of the word.
-As planes are added to the display hardware, they will occupy more
-significant bits in the plane mask.
-</para>
-<para>
-<!-- .LP -->
-In graphics operations, given a source and destination pixel,
-the result is computed bitwise on corresponding bits of the pixels.
-That is, a Boolean operation is performed in each bit plane.
-The plane_mask restricts the operation to a subset of planes.
-A macro constant
-<symbol>AllPlanes</symbol>
-can be used to refer to all planes of the screen simultaneously.
-The result is computed by the following:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-((src FUNC dst) AND plane-mask) OR (dst AND (NOT plane-mask))
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-Range checking is not performed on the values for foreground,
-background, or plane_mask.
-They are simply truncated to the appropriate
-number of bits.
-The line-width is measured in pixels and either can be greater than or equal to
-one (wide line) or can be the special value zero (thin line).
-</para>
-<para>
-<!-- .LP -->
-Wide lines are drawn centered on the path described by the graphics request.
-Unless otherwise specified by the join-style or cap-style,
-the bounding box of a wide line with endpoints [x1, y1], [x2, y2] and
-width w is a rectangle with vertices at the following real coordinates:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-[x1-(w*sn/2), y1+(w*cs/2)], [x1+(w*sn/2), y1-(w*cs/2)],
-[x2-(w*sn/2), y2+(w*cs/2)], [x2+(w*sn/2), y2-(w*cs/2)]
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-Here sn is the sine of the angle of the line,
-and cs is the cosine of the angle of the line.
-A pixel is part of the line and so is drawn
-if the center of the pixel is fully inside the bounding box
-(which is viewed as having infinitely thin edges).
-If the center of the pixel is exactly on the bounding box,
-it is part of the line if and only if the interior is immediately to its right
-(x increasing direction).
-Pixels with centers on a horizontal edge are a special case and are part of
-the line if and only if the interior or the boundary is immediately below
-(y increasing direction) and the interior or the boundary is immediately
-to the right (x increasing direction).
-</para>
-<para>
-<!-- .LP -->
-Thin lines (zero line-width) are one-pixel-wide lines drawn using an
-unspecified, device-dependent algorithm.
-There are only two constraints on this algorithm.
-</para>
-<itemizedlist>
- <listitem>
- <para>
-If a line is drawn unclipped from [x1,y1] to [x2,y2] and
-if another line is drawn unclipped from [x1+dx,y1+dy] to [x2+dx,y2+dy],
-a point [x,y] is touched by drawing the first line
-if and only if the point [x+dx,y+dy] is touched by drawing the second line.
- </para>
- </listitem>
- <listitem>
- <para>
-The effective set of points comprising a line cannot be affected by clipping.
-That is, a point is touched in a clipped line if and only if the point
-lies inside the clipping region and the point would be touched
-by the line when drawn unclipped.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-A wide line drawn from [x1,y1] to [x2,y2] always draws the same pixels
-as a wide line drawn from [x2,y2] to [x1,y1], not counting cap-style
-and join-style.
-It is recommended that this property be true for thin lines,
-but this is not required.
-A line-width of zero may differ from a line-width of one in which pixels are
-drawn.
-This permits the use of many manufacturers' line drawing hardware,
-which may run many times faster than the more precisely specified
-wide lines.
-</para>
-<para>
-<!-- .LP -->
-In general,
-drawing a thin line will be faster than drawing a wide line of width one.
-However, because of their different drawing algorithms,
-thin lines may not mix well aesthetically with wide lines.
-If it is desirable to obtain precise and uniform results across all displays,
-a client should always use a line-width of one rather than a line-width of zero.
-</para>
-<para>
-<!-- .LP -->
-The line-style defines which sections of a line are drawn:
-</para>
-
-<variablelist>
- <varlistentry>
- <term><symbol>LineSolid</symbol></term>
- <listitem>
- <para>The full path of the line is drawn.</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><symbol>LineDoubleDash</symbol></term>
- <listitem>
- <para>
-The full path of the line is drawn,
-but the even dashes are filled differently
-from the odd dashes (see fill-style) with <!-- xref -->
-<symbol>CapButt</symbol>
-style used where even and odd dashes meet.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><symbol>LineOnOffDash</symbol></term>
- <listitem>
- <para>
-Only the even dashes are drawn,
-and cap-style applies to
-all internal ends of the individual dashes,
-except
-<symbol>CapNotLast</symbol>
-is treated as
-<symbol>CapButt</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-<para>
-The cap-style defines how the endpoints of a path are drawn:
-</para>
-
-<variablelist>
- <varlistentry>
- <term><symbol>CapNotLast</symbol></term>
- <listitem>
- <para>
-This is equivalent to
-<symbol>CapButt</symbol>
-except that for a line-width of zero the final endpoint is not drawn.
- </para>
- </listitem>
- </varlistentry>
-
- <varlistentry>
- <term><symbol>CapButt</symbol></term>
- <listitem>
- <para>
-The line is square at the endpoint (perpendicular to the slope of the line)
-with no projection beyond.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><symbol>CapRound</symbol></term>
- <listitem>
- <para>
-The line has a circular arc with the diameter equal to the line-width,
-centered on the endpoint.
-(This is equivalent to
-<symbol>CapButt</symbol>
-for line-width of zero).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><symbol>CapProjecting</symbol></term>
- <listitem>
- <para>
-The line is square at the end, but the path continues beyond the endpoint
-for a distance equal to half the line-width.
-(This is equivalent to
-<symbol>CapButt</symbol>
-for line-width of zero).
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-The join-style defines how corners are drawn for wide lines:
-</para>
-
-<variablelist>
- <varlistentry>
- <term><symbol>JoinMiter</symbol></term>
- <listitem>
- <para>
-The outer edges of two lines extend to meet at an angle.
-However, if the angle is less than 11 degrees,
-then a
-<symbol>JoinBevel</symbol>
-join-style is used instead.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><symbol>JoinRound</symbol></term>
- <listitem>
- <para>
-The corner is a circular arc with the diameter equal to the line-width,
-centered on the joinpoint.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><symbol>JoinBevel</symbol></term>
- <listitem>
- <para>
-The corner has
-<symbol>CapButt</symbol>
-endpoint styles with the triangular notch filled.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-
-<para>
-<!-- .LP -->
-For a line with coincident endpoints (x1=x2, y1=y2),
-when the cap-style is applied to both endpoints,
-the semantics depends on the line-width and the cap-style:
-</para>
-
-<informaltable>
- <tgroup cols='3' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <tbody>
- <row>
- <entry><symbol>CapNotLast</symbol></entry>
- <entry>thin</entry>
- <entry>The results are device dependent,
- but the desired effect is that nothing is drawn.</entry>
- </row>
- <row>
- <entry><symbol>CapButt</symbol></entry>
- <entry>thin</entry>
- <entry>The results are device dependent,
- but the desired effect is that a single pixel is drawn.</entry>
- </row>
- <row>
- <entry><symbol>CapRound</symbol></entry>
- <entry>thin</entry>
- <entry>The results are the same as for
- <symbol>CapButt</symbol> /thin.</entry>
- </row>
- <row>
- <entry><symbol>CapProjecting</symbol></entry>
- <entry>thin</entry>
- <entry>The results are the same as for
- <symbol>CapButt</symbol> /thin.</entry>
- </row>
- <row>
- <entry><symbol>CapButt</symbol></entry>
- <entry>wide</entry>
- <entry>Nothing is drawn.</entry>
- </row>
- <row>
- <entry><symbol>CapRound</symbol></entry>
- <entry>wide</entry>
- <entry>The closed path is a circle, centered at the endpoint, and
- with the diameter equal to the line-width.</entry>
- </row>
- <row>
- <entry><symbol>CapProjecting</symbol></entry>
- <entry>wide</entry>
- <entry>The closed path is a square, aligned with the coordinate axes, centered at the
- endpoint, and with the sides equal to the line-width.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-For a line with coincident endpoints (x1=x2, y1=y2),
-when the join-style is applied at one or both endpoints,
-the effect is as if the line was removed from the overall path.
-However, if the total path consists of or is reduced to a single point joined
-with itself, the effect is the same as when the cap-style is applied at both
-endpoints.
-</para>
-<para>
-<!-- .LP -->
-The tile/stipple represents an infinite two-dimensional plane,
-with the tile/stipple replicated in all dimensions.
-When that plane is superimposed on the drawable
-for use in a graphics operation, the upper-left corner
-of some instance of the tile/stipple is at the coordinates within
-the drawable specified by the tile/stipple origin.
-The tile/stipple and clip origins are interpreted relative to the
-origin of whatever destination drawable is specified in a graphics
-request.
-The tile pixmap must have the same root and depth as the GC,
-or a
-<errorname>BadMatch</errorname>
-error results.
-The stipple pixmap must have depth one and must have the same root as the
-GC, or a
-<errorname>BadMatch</errorname>
-error results.
-For stipple operations where the fill-style is
-<symbol>FillStippled</symbol>
-but not
-<symbol>FillOpaqueStippled</symbol>,
-the stipple pattern is tiled in a
-single plane and acts as an additional clip mask to be ANDed with the clip-mask.
-Although some sizes may be faster to use than others,
-any size pixmap can be used for tiling or stippling.
-</para>
-
-<para>
-<!-- .LP -->
-The fill-style defines the contents of the source for line, text, and
-fill requests.
-For all text and fill requests (for example,
-<function>XDrawText</function>,
-<function>XDrawText16</function>,
-<function>XFillRectangle</function>,
-<function>XFillPolygon</function>,
-and
-<function>XFillArc</function>);
-for line requests
-with line-style
-<symbol>LineSolid</symbol>
-(for example,
-<function>XDrawLine</function>,
-<function>XDrawSegments</function>,
-<function>XDrawRectangle</function>,
-<function>XDrawArc</function>);
-and for the even dashes for line requests with line-style
-<symbol>LineOnOffDash</symbol>
-or
-<symbol>LineDoubleDash</symbol>,
-the following apply:
-</para>
-
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <tbody>
- <row>
- <entry><symbol>FillSolid</symbol></entry>
- <entry>Foreground</entry>
- </row>
- <row>
- <entry><symbol>FillTiled</symbol></entry>
- <entry>Tile</entry>
- </row>
- <row>
- <entry><symbol>FillOpaqueStippled</symbol></entry>
- <entry>A tile with the same width and height as stipple,
- but with background everywhere stipple has a zero
- and with foreground everywhere stipple has a one</entry>
- </row>
- <row>
- <entry><symbol>FillStippled</symbol></entry>
- <entry>Foreground masked by stipple</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-When drawing lines with line-style
-<symbol>LineDoubleDash</symbol>,
-the odd dashes are controlled by the fill-style in the following manner:
-</para>
-
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <tbody>
- <row>
- <entry><symbol>FillSolid</symbol></entry>
- <entry>Background</entry>
- </row>
- <row>
- <entry><symbol>FillTiled</symbol></entry>
- <entry>Same as for even dashes</entry>
- </row>
- <row>
- <entry><symbol>FillOpaqueStippled</symbol></entry>
- <entry>Same as for even dashes</entry>
- </row>
- <row>
- <entry><symbol>FillStippled</symbol></entry>
- <entry>Background masked by stipple</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-Storing a pixmap in a GC might or might not result in a copy
-being made.
-If the pixmap is later used as the destination for a graphics request,
-the change might or might not be reflected in the GC.
-If the pixmap is used simultaneously in a graphics request both as
-a destination and as a tile or stipple,
-the results are undefined.
-</para>
-<para>
-<!-- .LP -->
-For optimum performance,
-you should draw as much as possible with the same GC
-(without changing its components).
-The costs of changing GC components relative to using different GCs
-depend on the display hardware and the server implementation.
-It is quite likely that some amount of GC information will be
-cached in display hardware and that such hardware can only cache a small number
-of GCs.
-</para>
-<para>
-<!-- .LP -->
-The dashes value is actually a simplified form of the
-more general patterns that can be set with
-<function>XSetDashes</function>.
-Specifying a
-value of N is equivalent to specifying the two-element list [N, N] in
-<function>XSetDashes</function>.
-The value must be nonzero,
-or a
-<errorname>BadValue</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-The clip-mask restricts writes to the destination drawable.
-If the clip-mask is set to a pixmap,
-it must have depth one and have the same root as the GC,
-or a
-<errorname>BadMatch</errorname>
-error results.
-If clip-mask is set to
-<symbol>None</symbol>,
-the pixels are always drawn regardless of the clip origin.
-The clip-mask also can be set by calling the
-<function>XSetClipRectangles</function>
-or
-<function>XSetRegion</function>
-functions.
-Only pixels where the clip-mask has a bit set to 1 are drawn.
-Pixels are not drawn outside the area covered by the clip-mask
-or where the clip-mask has a bit set to 0.
-The clip-mask affects all graphics requests.
-The clip-mask does not clip sources.
-The clip-mask origin is interpreted relative to the origin of whatever
-destination drawable is specified in a graphics request.
-</para>
-<para>
-<!-- .LP -->
-You can set the subwindow-mode to
-<symbol>ClipByChildren</symbol>
-or
-<symbol>IncludeInferiors</symbol>.
-For
-<symbol>ClipByChildren</symbol>,
-both source and destination windows are
-additionally clipped by all viewable
-<symbol>InputOutput</symbol>
-children.
-For
-<symbol>IncludeInferiors</symbol>,
-neither source nor destination window is clipped by inferiors.
-This will result in including subwindow contents in the source
-and drawing through subwindow boundaries of the destination.
-The use of
-<symbol>IncludeInferiors</symbol>
-on a window of one depth with mapped
-inferiors of differing depth is not illegal, but the semantics are
-undefined by the core protocol.
-</para>
-<para>
-<!-- .LP -->
-The fill-rule defines what pixels are inside (drawn) for
-paths given in
-<function>XFillPolygon</function>
-requests and can be set to
-<symbol>EvenOddRule</symbol>
-or
-<symbol>WindingRule</symbol>.
-For
-<symbol>EvenOddRule</symbol>,
-a point is inside if
-an infinite ray with the point as origin crosses the path an odd number
-of times.
-For
-<symbol>WindingRule</symbol>,
-a point is inside if an infinite ray with the
-point as origin crosses an unequal number of clockwise and
-counterclockwise directed path segments.
-A clockwise directed path segment is one that crosses the ray from left to
-right as observed from the point.
-A counterclockwise segment is one that crosses the ray from right to left
-as observed from the point.
-The case where a directed line segment is coincident with the ray is
-uninteresting because you can simply choose a different ray that is not
-coincident with a segment.
-</para>
-<para>
-<!-- .LP -->
-For both
-<symbol>EvenOddRule</symbol>
-and
-<symbol>WindingRule</symbol>,
-a point is infinitely small,
-and the path is an infinitely thin line.
-A pixel is inside if the center point of the pixel is inside
-and the center point is not on the boundary.
-If the center point is on the boundary,
-the pixel is inside if and only if the polygon interior is immediately to
-its right (x increasing direction).
-Pixels with centers on a horizontal edge are a special case
-and are inside if and only if the polygon interior is immediately below
-(y increasing direction).
-</para>
-<para>
-<!-- .LP -->
-The arc-mode controls filling in the
-<function>XFillArcs</function>
-function and can be set to
-<symbol>ArcPieSlice</symbol>
-or
-<symbol>ArcChord</symbol>.
-For
-<symbol>ArcPieSlice</symbol>,
-the arcs are pie-slice filled.
-For
-<symbol>ArcChord</symbol>,
-the arcs are chord filled.
-</para>
-<para>
-<!-- .LP -->
-The graphics-exposure flag controls
-<symbol>GraphicsExpose</symbol>
-event generation
-for
-<function>XCopyArea</function>
-and
-<function>XCopyPlane</function>
-requests (and any similar requests defined by extensions).
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create a new GC that is usable on a given screen with a
-depth of drawable, use
-<function>XCreateGC</function>.
-<indexterm><primary>Graphics context</primary><secondary>initializing</secondary></indexterm>
-<indexterm significance="preferred"><primary>XCreateGC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>GC <function>XCreateGC</function></funcdef>
- <paramdef>Display <parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>unsignedlong<parameter> valuemask</parameter></paramdef>
- <paramdef>XGCValues *<parameter>values</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
-<!-- .ds Vm set using the information in the specified values structure -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>valuemask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which components in the GC are to be (Vm.
-This argument is the bitwise inclusive OR of zero or more of the valid
-GC component mask bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>values</emphasis>
- </term>
- <listitem>
- <para>
-Specifies any values as specified by the valuemask.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreateGC</function>
-function creates a graphics context and returns a GC.
-The GC can be used with any destination drawable having the same root
-and depth as the specified drawable.
-Use with other drawables results in a
-<errorname>BadMatch</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreateGC</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadDrawable</errorname>,
-<errorname>BadFont</errorname>,
-<errorname>BadMatch</errorname>,
-<errorname>BadPixmap</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To copy components from a source GC to a destination GC, use
-<function>XCopyGC</function>.
-<indexterm significance="preferred"><primary>XCopyGC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XCopyGC</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GCsrc,<parameter> dest</parameter></paramdef>
- <paramdef>unsignedlong<parameter> valuemask</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the components of the source GC.
-<!-- .ds Vm copied to the destination GC -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>valuemask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which components in the GC are to be (Vm.
-This argument is the bitwise inclusive OR of zero or more of the valid
-GC component mask bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the destination GC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCopyGC</function>
-function copies the specified components from the source GC
-to the destination GC.
-The source and destination GCs must have the same root and depth,
-or a
-<errorname>BadMatch</errorname>
-error results.
-The valuemask specifies which component to copy, as for
-<function>XCreateGC</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XCopyGC</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadMatch</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To change the components in a given GC, use
-<function>XChangeGC</function>.
-<indexterm significance="preferred"><primary>XChangeGC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XChangeGC</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>unsignedlong<parameter> valuemask</parameter></paramdef>
- <paramdef>XGCValues<parameter> *values</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Vm changed using information in the specified values structure -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>valuemask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which components in the GC are to be (Vm.
-This argument is the bitwise inclusive OR of zero or more of the valid
-GC component mask bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>values</emphasis>
- </term>
- <listitem>
- <para>
-Specifies any values as specified by the valuemask.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XChangeGC</function>
-function changes the components specified by valuemask for
-the specified GC.
-The values argument contains the values to be set.
-The values and restrictions are the same as for
-<function>XCreateGC</function>.
-Changing the clip-mask overrides any previous
-<function>XSetClipRectangles</function>
-request on the context.
-Changing the dash-offset or dash-list
-overrides any previous
-<function>XSetDashes</function>
-request on the context.
-The order in which components are verified and altered is server dependent.
-If an error is generated, a subset of the components may have been altered.
-</para>
-<para>
-<!-- .LP -->
-<function>XChangeGC</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadFont</errorname>,
-<errorname>BadGC</errorname>,
-<errorname>BadMatch</errorname>,
-<errorname>BadPixmap</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain components of a given GC, use
-<function>XGetGCValues</function>.
-<indexterm significance="preferred"><primary>XGetGCValues</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetGCValues</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>unsignedlong<parameter> valuemask</parameter></paramdef>
- <paramdef>XGCValues<parameter> *values_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Vm returned in the values_return argument -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>valuemask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which components in the GC are to be (Vm.
-This argument is the bitwise inclusive OR of zero or more of the valid
-GC component mask bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>values_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the GC values in the specified
-<structname>XGCValues</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetGCValues</function>
-function returns the components specified by valuemask for the specified GC.
-If the valuemask contains a valid set of GC mask bits
-(<symbol>GCFunction</symbol>,
-<symbol>GCPlaneMask</symbol>,
-<symbol>GCForeground</symbol>,
-<symbol>GCBackground</symbol>,
-<symbol>GCLineWidth</symbol>,
-<symbol>GCLineStyle</symbol>,
-<symbol>GCCapStyle</symbol>,
-<symbol>GCJoinStyle</symbol>,
-<symbol>GCFillStyle</symbol>,
-<symbol>GCFillRule</symbol>,
-<symbol>GCTile</symbol>,
-<symbol>GCStipple</symbol>,
-<symbol>GCTileStipXOrigin</symbol>,
-<symbol>GCTileStipYOrigin</symbol>,
-<symbol>GCFont</symbol>,
-<symbol>GCSubwindowMode</symbol>,
-<symbol>GCGraphicsExposures</symbol>,
-<symbol>GCClipXOrigin</symbol>,
-<symbol>GCClipYOrigin</symbol>,
-<symbol>GCDashOffset</symbol>,
-or
-<symbol>GCArcMode</symbol>)
-and no error occurs,
-<function>XGetGCValues</function>
-sets the requested components in values_return and returns a nonzero status.
-Otherwise, it returns a zero status.
-Note that the clip-mask and dash-list (represented by the
-<symbol>GCClipMask</symbol>
-and
-<symbol>GCDashList</symbol>
-bits, respectively, in the valuemask)
-cannot be requested.
-Also note that an invalid resource ID (with one or more of the three
-most significant bits set to 1) will be returned for
-<symbol>GCFont</symbol>,
-<symbol>GCTile</symbol>,
-and
-<symbol>GCStipple</symbol>
-if the component has never been explicitly set by the client.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To free a given GC, use
-<function>XFreeGC</function>.
-<indexterm significance="preferred"><primary>XFreeGC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFreeGC</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreeGC</function>
-function destroys the specified GC as well as all the associated storage.
-</para>
-<para>
-<!-- .LP -->
-<function>XFreeGC</function>
-can generate a
-<errorname>BadGC</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the
-<type>GContext</type>
-resource ID for a given GC, use
-<function>XGContextFromGC</function>.
-<indexterm significance="preferred"><primary>XGContextFromGC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>GContext <function>XGContextFromGC</function></funcdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<!-- .ds Gc for which you want the resource ID -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC (Gc.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-Xlib usually defers sending changes to the components of a GC to the server
-until a graphics function is actually called with that GC.
-This permits batching of component changes into a single server request.
-In some circumstances, however, it may be necessary for the client
-to explicitly force sending the changes to the server.
-An example might be when a protocol extension uses the GC indirectly,
-in such a way that the extension interface cannot know what GC will be used.
-To force sending GC component changes, use
-<function>XFlushGC</function>.
-<indexterm significance="preferred"><primary>XFlushGC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XFlushGC</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-</para>
-</sect1>
-<sect1 id="Using_Graphics_Context_Convenience_Routines">
-<title>Using Graphics Context Convenience Routines</title>
-<!-- .XS -->
-<!-- (SN Using Graphics Context Convenience Routines -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This section discusses how to set the:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Foreground, background, plane mask, or function components
- </para>
- </listitem>
- <listitem>
- <para>
-Line attributes and dashes components
- </para>
- </listitem>
- <listitem>
- <para>
-Fill style and fill rule components
- </para>
- </listitem>
- <listitem>
- <para>
-Fill tile and stipple components
- </para>
- </listitem>
- <listitem>
- <para>
-Font component
- </para>
- </listitem>
- <listitem>
- <para>
-Clip region component
- </para>
- </listitem>
- <listitem>
- <para>
-Arc mode, subwindow mode, and graphics exposure components
- </para>
- </listitem>
-</itemizedlist>
-<sect2 id="Setting_the_Foreground_Background_Function_or_Plane_Mask">
-<title>Setting the Foreground, Background, Function, or Plane Mask</title>
-<!-- .XS -->
-<!-- (SN Setting the Foreground, Background, Function, or Plane Mask -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To set the foreground, background, plane mask, and function components
-for a given GC, use
-<function>XSetState</function>.
-<indexterm significance="preferred"><primary>XSetState</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetState</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>unsignedlongforeground,<parameter> background</parameter></paramdef>
- <paramdef>int<parameter> function</parameter></paramdef>
- <paramdef>unsignedlong<parameter> plane_mask</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>foreground</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the foreground you want to set for the specified GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>background</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the background you want to set for the specified GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>function</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the function you want to set for the specified GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>plane_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the plane mask.
-<!-- .\" *** JIM: NEED MORE INFO FOR THIS. *** -->
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XSetState</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the foreground of a given GC, use
-<function>XSetForeground</function>.
-<indexterm significance="preferred"><primary>XSetForeground</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetForeground</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>unsignedlong<parameter> foreground</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>foreground</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the foreground you want to set for the specified GC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XSetForeground</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadGC</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the background of a given GC, use
-<function>XSetBackground</function>.
-<indexterm significance="preferred"><primary>XSetBackground</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetBackground</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>unsignedlong<parameter> background</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>background</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the background you want to set for the specified GC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XSetBackground</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadGC</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the display function in a given GC, use
-<function>XSetFunction</function>.
-<indexterm significance="preferred"><primary>XSetFunction</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetFunction</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>int<parameter> function</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>function</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the function you want to set for the specified GC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XSetFunction</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the plane mask of a given GC, use
-<function>XSetPlaneMask</function>.
-<indexterm significance="preferred"><primary>XSetPlaneMask</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetPlaneMask</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>unsignedlong<parameter> plane_mask</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>plane_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the plane mask.
-<!-- .\" *** JIM: NEED MORE INFO FOR THIS. *** -->
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XSetPlaneMask</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadGC</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Setting_the_Line_Attributes_and_Dashes">
-<title>Setting the Line Attributes and Dashes</title>
-<!-- .XS -->
-<!-- (SN Setting the Line Attributes and Dashes -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To set the line drawing components of a given GC, use
-<function>XSetLineAttributes</function>.
-<indexterm significance="preferred"><primary>XSetLineAttributes</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetLineAttributes</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>unsignedint<parameter> line_width</parameter></paramdef>
- <paramdef>int<parameter> line_style</parameter></paramdef>
- <paramdef>int<parameter> cap_style</parameter></paramdef>
- <paramdef>int<parameter> join_style</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>line_width</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the line-width you want to set for the specified GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>line_style</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the line-style you want to set for the specified GC.
-You can pass
-<symbol>LineSolid</symbol>,
-<symbol>LineOnOffDash</symbol>,
-or
-<symbol>LineDoubleDash</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>cap_style</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the line-style and cap-style you want to set for the specified GC.
-You can pass
-<symbol>CapNotLast</symbol>,
-<symbol>CapButt</symbol>,
-<symbol>CapRound</symbol>,
-or
-<symbol>CapProjecting</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>join_style</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the line join-style you want to set for the specified GC.
-You can pass
-<symbol>JoinMiter</symbol>,
-<symbol>JoinRound</symbol>,
-or
-<symbol>JoinBevel</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XSetLineAttributes</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the dash-offset and dash-list for dashed line styles of a given GC, use
-<function>XSetDashes</function>.
-<indexterm significance="preferred"><primary>XSetDashes</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetDashes</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>int<parameter> dash_offset</parameter></paramdef>
- <paramdef>char<parameter> dash_list[]</parameter></paramdef>
- <paramdef>int<parameter> n</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dash_offset</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the phase of the pattern for the dashed line-style you want to set
-for the specified GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dash_list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the dash-list for the dashed line-style
-you want to set for the specified GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>n</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of elements in dash_list.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetDashes</function>
-function sets the dash-offset and dash-list attributes for dashed line styles
-in the specified GC.
-There must be at least one element in the specified dash_list,
-or a
-<errorname>BadValue</errorname>
-error results.
-The initial and alternating elements (second, fourth, and so on)
-of the dash_list are the even dashes, and
-the others are the odd dashes.
-Each element specifies a dash length in pixels.
-All of the elements must be nonzero,
-or a
-<errorname>BadValue</errorname>
-error results.
-Specifying an odd-length list is equivalent to specifying the same list
-concatenated with itself to produce an even-length list.
-</para>
-<para>
-<!-- .LP -->
-The dash-offset defines the phase of the pattern,
-specifying how many pixels into the dash-list the pattern
-should actually begin in any single graphics request.
-Dashing is continuous through path elements combined with a join-style
-but is reset to the dash-offset between each sequence of joined lines.
-</para>
-<para>
-<!-- .LP -->
-The unit of measure for dashes is the same for the ordinary coordinate system.
-Ideally, a dash length is measured along the slope of the line, but implementations
-are only required to match this ideal for horizontal and vertical lines.
-Failing the ideal semantics, it is suggested that the length be measured along the
-major axis of the line.
-The major axis is defined as the x axis for lines drawn at an angle of between
-&minus;45 and +45 degrees or between 135 and 225 degrees from the x axis.
-For all other lines, the major axis is the y axis.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetDashes</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Setting_the_Fill_Style_and_Fill_Rule_">
-<title>Setting the Fill Style and Fill Rule </title>
-<!-- .XS -->
-<!-- (SN Setting the Fill Style and Fill Rule -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To set the fill-style of a given GC, use
-<function>XSetFillStyle</function>.
-<indexterm significance="preferred"><primary>XSetFillStyle</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetFillStyle</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>int<parameter> fill_style</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>fill_style</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the fill-style you want to set for the specified GC.
-You can pass
-<symbol>FillSolid</symbol>,
-<symbol>FillTiled</symbol>,
-<symbol>FillStippled</symbol>,
-or
-<symbol>FillOpaqueStippled</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XSetFillStyle</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the fill-rule of a given GC, use
-<function>XSetFillRule</function>.
-<indexterm significance="preferred"><primary>XSetFillRule</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetFillRule</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>int<parameter> fill_rule</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>fill_rule</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the fill-rule you want to set for the specified GC.
-You can pass
-<symbol>EvenOddRule</symbol>
-or
-<symbol>WindingRule</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XSetFillRule</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Setting_the_Fill_Tile_and_Stipple_">
-<title>Setting the Fill Tile and Stipple </title>
-<!-- .XS -->
-<!-- (SN Setting the Fill Tile and Stipple -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Some displays have hardware support for tiling or
-stippling with patterns of specific sizes.
-Tiling and stippling operations that restrict themselves to those specific
-sizes run much faster than such operations with arbitrary size patterns.
-Xlib provides functions that you can use to determine the best size,
-tile, or stipple for the display
-as well as to set the tile or stipple shape and the tile or stipple origin.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the best size of a tile, stipple, or cursor, use
-<function>XQueryBestSize</function>.
-<indexterm significance="preferred"><primary>XQueryBestSize</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XQueryBestSize</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> class</parameter></paramdef>
- <paramdef>Drawable<parameter> which_screen</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>class</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the class that you are interested in.
-You can pass
-<symbol>TileShape</symbol>,
-<symbol>CursorShape</symbol>,
-or
-<symbol>StippleShape</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>which_screen</emphasis>
- </term>
- <listitem>
- <para>
-Specifies any drawable on the screen.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the width and height of the object best supported
-by the display hardware.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XQueryBestSize</function>
-function returns the best or closest size to the specified size.
-For
-<symbol>CursorShape</symbol>,
-this is the largest size that can be fully displayed on the screen specified by
-which_screen.
-For
-<symbol>TileShape</symbol>,
-this is the size that can be tiled fastest.
-For
-<symbol>StippleShape</symbol>,
-this is the size that can be stippled fastest.
-For
-<symbol>CursorShape</symbol>,
-the drawable indicates the desired screen.
-For
-<symbol>TileShape</symbol>
-and
-<symbol>StippleShape</symbol>,
-the drawable indicates the screen and possibly the window class and depth.
-An
-<symbol>InputOnly</symbol>
-window cannot be used as the drawable for
-<symbol>TileShape</symbol>
-or
-<symbol>StippleShape</symbol>,
-or a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XQueryBestSize</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadMatch</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the best fill tile shape, use
-<function>XQueryBestTile</function>.
-<indexterm significance="preferred"><primary>XQueryBestTile</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XQueryBestTile</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> which_screen</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>which_screen</emphasis>
- </term>
- <listitem>
- <para>
-Specifies any drawable on the screen.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the width and height of the object best supported
-by the display hardware.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XQueryBestTile</function>
-function returns the best or closest size, that is, the size that can be
-tiled fastest on the screen specified by which_screen.
-The drawable indicates the screen and possibly the window class and depth.
-If an
-<symbol>InputOnly</symbol>
-window is used as the drawable, a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XQueryBestTile</function>
-can generate
-<errorname>BadDrawable</errorname>
-and
-<errorname>BadMatch</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the best stipple shape, use
-<function>XQueryBestStipple</function>.
-<indexterm significance="preferred"><primary>XQueryBestStipple</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XQueryBestStipple</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> which_screen</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>which_screen</emphasis>
- </term>
- <listitem>
- <para>
-Specifies any drawable on the screen.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the width and height of the object best supported
-by the display hardware.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XQueryBestStipple</function>
-function returns the best or closest size, that is, the size that can be
-stippled fastest on the screen specified by which_screen.
-The drawable indicates the screen and possibly the window class and depth.
-If an
-<symbol>InputOnly</symbol>
-window is used as the drawable, a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XQueryBestStipple</function>
-can generate
-<errorname>BadDrawable</errorname>
-and
-<errorname>BadMatch</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the fill tile of a given GC, use
-<function>XSetTile</function>.
-<indexterm significance="preferred"><primary>XSetTile</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetTile</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>Pixmap<parameter> tile</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>tile</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the fill tile you want to set for the specified GC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The tile and GC must have the same depth,
-or a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetTile</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-<errorname>BadMatch</errorname>,
-and
-<errorname>BadPixmap</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the stipple of a given GC, use
-<function>XSetStipple</function>.
-<indexterm significance="preferred"><primary>XSetStipple</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetStipple</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>Pixmap<parameter> stipple</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>stipple</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the stipple you want to set for the specified GC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The stipple must have a depth of one,
-or a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetStipple</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-<errorname>BadMatch</errorname>,
-and
-<errorname>BadPixmap</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the tile or stipple origin of a given GC, use
-<function>XSetTSOrigin</function>.
-<indexterm significance="preferred"><primary>XSetTSOrigin</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetTSOrigin</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intts_x_origin,<parameter> ts_y_origin</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ts_x_origin</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ts_y_origin</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates of the tile and stipple origin.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-When graphics requests call for tiling or stippling,
-the parent's origin will be interpreted relative to whatever destination
-drawable is specified in the graphics request.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetTSOrigin</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadGC</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Setting_the_Current_Font_">
-<title>Setting the Current Font </title>
-<!-- .XS -->
-<!-- (SN Setting the Current Font -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To set the current font of a given GC, use
-<function>XSetFont</function>.
-<indexterm significance="preferred"><primary>XSetFont</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetFont</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>Font<parameter> font</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XSetFont</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadFont</errorname>,
-and
-<errorname>BadGC</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Setting_the_Clip_Region">
-<title>Setting the Clip Region</title>
-<!-- .XS -->
-<!-- (SN Setting the Clip Region -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set the clip-origin
-and the clip-mask or set the clip-mask to a list of rectangles.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the clip-origin of a given GC, use
-<function>XSetClipOrigin</function>.
-<indexterm significance="preferred"><primary>XSetClipOrigin</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetClipOrigin</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intclip_x_origin,<parameter> clip_y_origin</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>clip_x_origin</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>clip_y_origin</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates of the clip-mask origin.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The clip-mask origin is interpreted relative to the origin of whatever
-destination drawable is specified in the graphics request.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetClipOrigin</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadGC</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the clip-mask of a given GC to the specified pixmap, use
-<function>XSetClipMask</function>.
-<indexterm significance="preferred"><primary>XSetClipMask</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetClipMask</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>Pixmap<parameter> pixmap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pixmap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the pixmap or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If the clip-mask is set to
-<symbol>None</symbol>,
-the pixels are always drawn (regardless of the clip-origin).
-</para>
-<para>
-<!-- .LP -->
-<function>XSetClipMask</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-<errorname>BadMatch</errorname>,
-and
-<errorname>BadPixmap</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the clip-mask of a given GC to the specified list of rectangles, use
-<function>XSetClipRectangles</function>.
-<indexterm significance="preferred"><primary>XSetClipRectangles</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetClipRectangles</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intclip_x_origin,<parameter> clip_y_origin</parameter></paramdef>
- <paramdef>XRectangle<parameter> rectangles[]</parameter></paramdef>
- <paramdef>int<parameter> n</parameter></paramdef>
- <paramdef>int<parameter> ordering</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>clip_x_origin</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>clip_y_origin</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates of the clip-mask origin.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>rectangles</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of rectangles that define the clip-mask.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>n</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of rectangles.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ordering</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the ordering relations on the rectangles.
-You can pass
-<symbol>Unsorted</symbol>,
-<symbol>YSorted</symbol>,
-<symbol>YXSorted</symbol>,
-or
-<symbol>YXBanded</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetClipRectangles</function>
-function changes the clip-mask in the specified GC
-to the specified list of rectangles and sets the clip origin.
-The output is clipped to remain contained within the
-rectangles.
-The clip-origin is interpreted relative to the origin of
-whatever destination drawable is specified in a graphics request.
-The rectangle coordinates are interpreted relative to the clip-origin.
-The rectangles should be nonintersecting, or the graphics results will be
-undefined.
-Note that the list of rectangles can be empty,
-which effectively disables output.
-This is the opposite of passing
-<symbol>None</symbol>
-as the clip-mask in
-<function>XCreateGC</function>,
-<function>XChangeGC</function>,
-and
-<function>XSetClipMask</function>.
-</para>
-<para>
-<!-- .LP -->
-If known by the client, ordering relations on the rectangles can be
-specified with the ordering argument.
-This may provide faster operation
-by the server.
-If an incorrect ordering is specified, the X server may generate a
-<errorname>BadMatch</errorname>
-error, but it is not required to do so.
-If no error is generated, the graphics
-results are undefined.
-<symbol>Unsorted</symbol>
-means the rectangles are in arbitrary order.
-<symbol>YSorted</symbol>
-means that the rectangles are nondecreasing in their Y origin.
-<symbol>YXSorted</symbol>
-additionally constrains
-<symbol>YSorted</symbol>
-order in that all
-rectangles with an equal Y origin are nondecreasing in their X
-origin.
-<symbol>YXBanded</symbol>
-additionally constrains
-<symbol>YXSorted</symbol>
-by requiring that,
-for every possible Y scanline, all rectangles that include that
-scanline have an identical Y origins and Y extents.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetClipRectangles</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-<errorname>BadMatch</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-Xlib provides a set of basic functions for performing
-region arithmetic.
-For information about these functions,
-see section 16.5.
-</para>
-</sect2>
-<sect2 id="Setting_the_Arc_Mode_Subwindow_Mode_and_Graphics_Exposure_">
-<title>Setting the Arc Mode, Subwindow Mode, and Graphics Exposure </title>
-<!-- .XS -->
-<!-- (SN Setting the Arc Mode, Subwindow Mode, and Graphics Exposure -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To set the arc mode of a given GC, use
-<function>XSetArcMode</function>.
-<indexterm significance="preferred"><primary>XSetArcMode</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetArcMode</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>int<parameter> arc_mode</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>arc_mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the arc mode.
-You can pass
-<symbol>ArcChord</symbol>
-or
-<symbol>ArcPieSlice</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XSetArcMode</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the subwindow mode of a given GC, use
-<function>XSetSubwindowMode</function>.
-<indexterm significance="preferred"><primary>XSetSubwindowMode</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetSubwindowMode</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>int<parameter> subwindow_mode</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>subwindow_mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the subwindow mode.
-You can pass
-<symbol>ClipByChildren</symbol>
-or
-<symbol>IncludeInferiors</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XSetSubwindowMode</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the graphics-exposures flag of a given GC, use
-<function>XSetGraphicsExposures</function>.
-<indexterm significance="preferred"><primary>XSetGraphicsExposures</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetGraphicsExposures</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>Bool<parameter> graphics_exposures</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>graphics_exposures</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value that indicates whether you want
-<symbol>GraphicsExpose</symbol>
-and
-<symbol>NoExpose</symbol>
-events to be reported when calling
-<function>XCopyArea</function>
-and
-<function>XCopyPlane</function>
-with this GC.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XSetGraphicsExposures</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-<!-- .bp -->
-
-</para>
-</sect2>
-</sect1>
-</chapter>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<chapter id="graphics_context_functions">
+<title>Graphics Context Functions</title>
+
+<para>
+A number of resources are used when performing graphics operations in X. Most information
+about performing graphics (for example, foreground color, background color, line style, and so
+on) is stored in resources called graphics contexts (GCs). Most graphics operations (see chapter
+8) take a GC as an argument. Although in theory the X protocol permits sharing of GCs between
+applications, it is expected that applications will use their own GCs when performing operations.
+Sharing of GCs is highly discouraged because the library may cache GC state.
+</para>
+<para>
+Graphics operations can be performed to either windows or pixmaps, which collectively are
+called drawables. Each drawable exists on a single screen. A GC is created for a specific screen
+and drawable depth and can only be used with drawables of matching screen and depth.
+</para>
+<para>
+This chapter discusses how to:
+</para>
+<itemizedlist>
+ <listitem><para>Manipulate graphics context/state</para></listitem>
+ <listitem><para>Use graphics context convenience functions</para></listitem>
+</itemizedlist>
+
+<sect1 id="Manipulating_Graphics_Context_State">
+<title>Manipulating Graphics Context/State</title>
+<!-- .XS -->
+<!-- (SN Manipulating Graphics Context/State -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Most attributes of graphics operations are stored in GCs.
+These include line width, line style, plane mask, foreground, background,
+tile, stipple, clipping region, end style, join style, and so on.
+Graphics operations (for example, drawing lines) use these values
+to determine the actual drawing operation.
+Extensions to X may add additional components to GCs.
+The contents of a GC are private to Xlib.
+</para>
+<para>
+<!-- .LP -->
+Xlib implements a write-back cache for all elements of a GC that are not
+resource IDs to allow Xlib to implement the transparent coalescing of changes
+to GCs.
+For example,
+a call to
+<function>XSetForeground</function>
+of a GC followed by a call to
+<function>XSetLineAttributes</function>
+results in only a single-change GC protocol request to the server.
+GCs are neither expected nor encouraged to be shared between client
+applications, so this write-back caching should present no problems.
+Applications cannot share GCs without external synchronization.
+Therefore,
+sharing GCs between applications is highly discouraged.
+</para>
+<para>
+<!-- .LP -->
+To set an attribute of a GC,
+set the appropriate member of the
+<structname>XGCValues</structname>
+structure and OR in the corresponding value bitmask in your subsequent calls to
+<function>XCreateGC</function>.
+The symbols for the value mask bits and the
+<structname>XGCValues</structname>
+structure are:
+<!-- .sM -->
+</para>
+
+
+<literallayout class="monospaced">
+/* GC attribute value mask bits */
+
+#define GCFunction (1L&lt;&lt;0)
+#define GCPlaneMask (1L&lt;&lt;1)
+#define GCForeground (1L&lt;&lt;2)
+#define GCBackground (1L&lt;&lt;3)
+#define GCLineWidth (1L&lt;&lt;4)
+#define GCLineStyle (1L&lt;&lt;5)
+#define GCCapStyle (1L&lt;&lt;6)
+#define GCJoinStyle (1L&lt;&lt;7)
+#define GCFillStyle (1L&lt;&lt;8)
+#define GCFillRule (1L&lt;&lt;9)
+#define GCTile (1L&lt;&lt;10)
+#define GCStipple (1L&lt;&lt;11)
+#define GCTileStipXOrigin (1L&lt;&lt;12)
+#define GCTileStipYOrigin (1L&lt;&lt;13)
+#define GCFont (1L&lt;&lt;14)
+#define GCSubwindowMode (1L&lt;&lt;15)
+#define GCGraphicsExposures (1L&lt;&lt;16)
+#define GCClipXOrigin (1L&lt;&lt;17)
+#define GCClipYOrigin (1L&lt;&lt;18)
+#define GCClipMask (1L&lt;&lt;19)
+#define GCDashOffset (1L&lt;&lt;20)
+#define GCDashList (1L&lt;&lt;21)
+#define GCArcMode (1L&lt;&lt;22)
+</literallayout>
+
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+/* Values */
+
+typedef struct {
+ int function; /* logical operation */
+ unsigned long plane_mask; /* plane mask */
+ unsigned long foreground; /* foreground pixel */
+ unsigned long background; /* background pixel */
+ int line_width; /* line width (in pixels) */
+ int line_style; /* LineSolid, LineOnOffDash, LineDoubleDash */
+ int cap_style; /* CapNotLast, CapButt, CapRound, CapProjecting */
+ int join_style; /* JoinMiter, JoinRound, JoinBevel */
+ int fill_style; /* FillSolid, FillTiled, FillStippled FillOpaqueStippled*/
+ int fill_rule; /* EvenOddRule, WindingRule */
+ int arc_mode; /* ArcChord, ArcPieSlice */
+ Pixmap tile; /* tile pixmap for tiling operations */
+ Pixmap stipple; /* stipple 1 plane pixmap for stippling */
+ int ts_x_origin; /* offset for tile or stipple operations */
+ int ts_y_origin
+ Font font; /* default text font for text operations */
+ int subwindow_mode; /* ClipByChildren, IncludeInferiors */
+ Bool graphics_exposures; /* boolean, should exposures be generated */
+ int clip_x_origin; /* origin for clipping */
+ int clip_y_origin;
+ Pixmap clip_mask; /* bitmap clipping; other calls for rects */
+ int dash_offset; /* patterned/dashed line information */
+ char dashes;
+} XGCValues;
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The default GC values are:
+</para>
+<informaltable>
+ <tgroup cols='3' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <colspec colname='c3'/>
+ <thead>
+ <row>
+ <entry>Component</entry>
+ <entry>Default</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>function</entry>
+ <entry><symbol>GXcopy</symbol></entry>
+ </row>
+ <row>
+ <entry>plane_mask</entry>
+ <entry>All ones</entry>
+ </row>
+ <row>
+ <entry>foreground</entry>
+ <entry>0</entry>
+ </row>
+ <row>
+ <entry>background</entry>
+ <entry>1</entry>
+ </row>
+ <row>
+ <entry>line_width</entry>
+ <entry>0</entry>
+ </row>
+ <row>
+ <entry>line_style</entry>
+ <entry><symbol>LineSolid</symbol></entry>
+ </row>
+ <row>
+ <entry>cap_style</entry>
+ <entry><symbol>CapButt</symbol></entry>
+ </row>
+ <row>
+ <entry>join_style</entry>
+ <entry><symbol>JoinMiter</symbol></entry>
+ </row>
+ <row>
+ <entry>fill_style</entry>
+ <entry><symbol>FillSolid</symbol></entry>
+ </row>
+ <row>
+ <entry>fill_rule</entry>
+ <entry><symbol>EvenOddRule</symbol></entry>
+ </row>
+ <row>
+ <entry>arc_mode</entry>
+ <entry><symbol>ArcPieSlice</symbol></entry>
+ </row>
+ <row>
+ <entry>tile</entry>
+ <entry>Pixmap of unspecified size filled with foreground pixel</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>(that is, client specified pixel if any, else 0)</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>(subsequent changes to foreground do not affect this pixmap)</entry>
+ </row>
+ <row>
+ <entry>stipple</entry>
+ <entry>Pixmap of unspecified size filled with ones</entry>
+ </row>
+ <row>
+ <entry>ts_x_origin</entry>
+ <entry>0</entry>
+ </row>
+ <row>
+ <entry>ts_y_origin</entry>
+ <entry>0</entry>
+ </row>
+ <row>
+ <entry>font</entry>
+ <entry>&lt;implementation dependent&gt;</entry>
+ </row>
+ <row>
+ <entry>subwindow_mode</entry>
+ <entry><symbol>ClipByChildren</symbol></entry>
+ </row>
+ <row>
+ <entry>graphics_exposures</entry>
+ <entry><symbol>True</symbol></entry>
+ </row>
+ <row>
+ <entry>clip_x_origin</entry>
+ <entry>0</entry>
+ </row>
+ <row>
+ <entry>clip_y_origin</entry>
+ <entry>0</entry>
+ </row>
+ <row>
+ <entry>clip_mask</entry>
+ <entry><symbol>None</symbol></entry>
+ </row>
+ <row>
+ <entry>dash_offset</entry>
+ <entry>0</entry>
+ </row>
+ <row>
+ <entry>dashes</entry>
+ <entry>4 (that is, the list [4, 4])</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+Note that foreground and background are not set to any values likely
+to be useful in a window.
+</para>
+
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>Display Functions</primary></indexterm>
+<indexterm significance="preferred"><primary>Source</primary></indexterm>
+<indexterm significance="preferred"><primary>Destination</primary></indexterm>
+The function attributes of a GC are used when you update a section of
+a drawable (the destination) with bits from somewhere else (the source).
+The function in a GC defines how the new destination bits are to be
+computed from the source bits and the old destination bits.
+<symbol>GXcopy</symbol>
+is typically the most useful because it will work on a color display,
+but special applications may use other functions,
+particularly in concert with particular planes of a color display.
+The 16 GC functions, defined in
+<filename class="headerfile">&lt;X11/X.h&gt;</filename>,
+<indexterm type="file"><primary><filename class="headerfile">X11/X.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/X.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/X.h&gt;</filename></secondary></indexterm>
+are:
+</para>
+<!-- .\" are listed in Table 5-1 along with the -->
+<!-- .\"the associated hexadecimal code -->
+<!-- .\" and operation. -->
+<!-- .\".CP T 1 -->
+<!-- .\"Display Functions -->
+<informaltable>
+ <tgroup cols='3' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <colspec colname='c3'/>
+ <thead>
+ <row>
+ <entry>Function Name</entry>
+ <entry>Value</entry>
+ <entry>Operation</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><symbol>GXclear</symbol></entry>
+ <entry>0x0</entry>
+ <entry>0</entry>
+ </row>
+ <row>
+ <entry><symbol>GXand</symbol></entry>
+ <entry>0x1</entry>
+ <entry>src AND dst</entry>
+ </row>
+ <row>
+ <entry><symbol>GXandReverse</symbol></entry>
+ <entry>0x2</entry>
+ <entry>src AND NOT dst</entry>
+ </row>
+ <row>
+ <entry><symbol>GXcopy</symbol></entry>
+ <entry>0x3</entry>
+ <entry>src</entry>
+ </row>
+ <row>
+ <entry><symbol>GXandInverted</symbol></entry>
+ <entry>0x4</entry>
+ <entry>(NOT src) AND dst</entry>
+ </row>
+ <row>
+ <entry><symbol>GXnoop</symbol></entry>
+ <entry>0x5</entry>
+ <entry>dst</entry>
+ </row>
+ <row>
+ <entry><symbol>GXxor</symbol></entry>
+ <entry>0x6</entry>
+ <entry>src XOR dst</entry>
+ </row>
+ <row>
+ <entry><symbol>GXor</symbol></entry>
+ <entry>0x7</entry>
+ <entry>src OR dst</entry>
+ </row>
+ <row>
+ <entry><symbol>GXnor</symbol></entry>
+ <entry>0x8</entry>
+ <entry>(NOT src) AND (NOT dst)</entry>
+ </row>
+ <row>
+ <entry><symbol>GXequiv</symbol></entry>
+ <entry>0x9</entry>
+ <entry>(NOT src) XOR dst</entry>
+ </row>
+ <row>
+ <entry><symbol>GXinvert</symbol></entry>
+ <entry>0xa</entry>
+ <entry>NOT dst</entry>
+ </row>
+ <row>
+ <entry><symbol>GXorReverse</symbol></entry>
+ <entry>0xb</entry>
+ <entry>src OR (NOT dst)</entry>
+ </row>
+ <row>
+ <entry><symbol>GXcopyInverted</symbol></entry>
+ <entry>0xc</entry>
+ <entry>NOT src</entry>
+ </row>
+ <row>
+ <entry><symbol>GXorInverted</symbol></entry>
+ <entry>0xd</entry>
+ <entry>(NOT src) OR dst</entry>
+ </row>
+ <row>
+ <entry><symbol>GXnand</symbol></entry>
+ <entry>0xe</entry>
+ <entry>(NOT src) OR (NOT dst)</entry>
+ </row>
+ <row>
+ <entry><symbol>GXset</symbol></entry>
+ <entry>0xf</entry>
+ <entry>1</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+Many graphics operations depend on either pixel values or planes in a GC.
+<indexterm><primary>Pixel value</primary></indexterm>
+The planes attribute is of type long, and it specifies which planes of the
+destination are to be modified, one bit per plane.
+<indexterm><primary>Plane</primary><secondary>mask</secondary></indexterm>
+A monochrome display has only one plane and
+will be the least significant bit of the word.
+As planes are added to the display hardware, they will occupy more
+significant bits in the plane mask.
+</para>
+<para>
+<!-- .LP -->
+In graphics operations, given a source and destination pixel,
+the result is computed bitwise on corresponding bits of the pixels.
+That is, a Boolean operation is performed in each bit plane.
+The plane_mask restricts the operation to a subset of planes.
+A macro constant
+<symbol>AllPlanes</symbol>
+can be used to refer to all planes of the screen simultaneously.
+The result is computed by the following:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+((src FUNC dst) AND plane-mask) OR (dst AND (NOT plane-mask))
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+Range checking is not performed on the values for foreground,
+background, or plane_mask.
+They are simply truncated to the appropriate
+number of bits.
+The line-width is measured in pixels and either can be greater than or equal to
+one (wide line) or can be the special value zero (thin line).
+</para>
+<para>
+<!-- .LP -->
+Wide lines are drawn centered on the path described by the graphics request.
+Unless otherwise specified by the join-style or cap-style,
+the bounding box of a wide line with endpoints [x1, y1], [x2, y2] and
+width w is a rectangle with vertices at the following real coordinates:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+[x1-(w*sn/2), y1+(w*cs/2)], [x1+(w*sn/2), y1-(w*cs/2)],
+[x2-(w*sn/2), y2+(w*cs/2)], [x2+(w*sn/2), y2-(w*cs/2)]
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+Here sn is the sine of the angle of the line,
+and cs is the cosine of the angle of the line.
+A pixel is part of the line and so is drawn
+if the center of the pixel is fully inside the bounding box
+(which is viewed as having infinitely thin edges).
+If the center of the pixel is exactly on the bounding box,
+it is part of the line if and only if the interior is immediately to its right
+(x increasing direction).
+Pixels with centers on a horizontal edge are a special case and are part of
+the line if and only if the interior or the boundary is immediately below
+(y increasing direction) and the interior or the boundary is immediately
+to the right (x increasing direction).
+</para>
+<para>
+<!-- .LP -->
+Thin lines (zero line-width) are one-pixel-wide lines drawn using an
+unspecified, device-dependent algorithm.
+There are only two constraints on this algorithm.
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+If a line is drawn unclipped from [x1,y1] to [x2,y2] and
+if another line is drawn unclipped from [x1+dx,y1+dy] to [x2+dx,y2+dy],
+a point [x,y] is touched by drawing the first line
+if and only if the point [x+dx,y+dy] is touched by drawing the second line.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The effective set of points comprising a line cannot be affected by clipping.
+That is, a point is touched in a clipped line if and only if the point
+lies inside the clipping region and the point would be touched
+by the line when drawn unclipped.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+A wide line drawn from [x1,y1] to [x2,y2] always draws the same pixels
+as a wide line drawn from [x2,y2] to [x1,y1], not counting cap-style
+and join-style.
+It is recommended that this property be true for thin lines,
+but this is not required.
+A line-width of zero may differ from a line-width of one in which pixels are
+drawn.
+This permits the use of many manufacturers' line drawing hardware,
+which may run many times faster than the more precisely specified
+wide lines.
+</para>
+<para>
+<!-- .LP -->
+In general,
+drawing a thin line will be faster than drawing a wide line of width one.
+However, because of their different drawing algorithms,
+thin lines may not mix well aesthetically with wide lines.
+If it is desirable to obtain precise and uniform results across all displays,
+a client should always use a line-width of one rather than a line-width of zero.
+</para>
+<para>
+<!-- .LP -->
+The line-style defines which sections of a line are drawn:
+</para>
+
+<variablelist>
+ <varlistentry>
+ <term><symbol>LineSolid</symbol></term>
+ <listitem>
+ <para>The full path of the line is drawn.</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><symbol>LineDoubleDash</symbol></term>
+ <listitem>
+ <para>
+The full path of the line is drawn,
+but the even dashes are filled differently
+from the odd dashes (see fill-style) with <!-- xref -->
+<symbol>CapButt</symbol>
+style used where even and odd dashes meet.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><symbol>LineOnOffDash</symbol></term>
+ <listitem>
+ <para>
+Only the even dashes are drawn,
+and cap-style applies to
+all internal ends of the individual dashes,
+except
+<symbol>CapNotLast</symbol>
+is treated as
+<symbol>CapButt</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+<para>
+The cap-style defines how the endpoints of a path are drawn:
+</para>
+
+<variablelist>
+ <varlistentry>
+ <term><symbol>CapNotLast</symbol></term>
+ <listitem>
+ <para>
+This is equivalent to
+<symbol>CapButt</symbol>
+except that for a line-width of zero the final endpoint is not drawn.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><symbol>CapButt</symbol></term>
+ <listitem>
+ <para>
+The line is square at the endpoint (perpendicular to the slope of the line)
+with no projection beyond.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><symbol>CapRound</symbol></term>
+ <listitem>
+ <para>
+The line has a circular arc with the diameter equal to the line-width,
+centered on the endpoint.
+(This is equivalent to
+<symbol>CapButt</symbol>
+for line-width of zero).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><symbol>CapProjecting</symbol></term>
+ <listitem>
+ <para>
+The line is square at the end, but the path continues beyond the endpoint
+for a distance equal to half the line-width.
+(This is equivalent to
+<symbol>CapButt</symbol>
+for line-width of zero).
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+The join-style defines how corners are drawn for wide lines:
+</para>
+
+<variablelist>
+ <varlistentry>
+ <term><symbol>JoinMiter</symbol></term>
+ <listitem>
+ <para>
+The outer edges of two lines extend to meet at an angle.
+However, if the angle is less than 11 degrees,
+then a
+<symbol>JoinBevel</symbol>
+join-style is used instead.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><symbol>JoinRound</symbol></term>
+ <listitem>
+ <para>
+The corner is a circular arc with the diameter equal to the line-width,
+centered on the joinpoint.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><symbol>JoinBevel</symbol></term>
+ <listitem>
+ <para>
+The corner has
+<symbol>CapButt</symbol>
+endpoint styles with the triangular notch filled.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+
+<para>
+<!-- .LP -->
+For a line with coincident endpoints (x1=x2, y1=y2),
+when the cap-style is applied to both endpoints,
+the semantics depends on the line-width and the cap-style:
+</para>
+
+<informaltable>
+ <tgroup cols='3' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <colspec colname='c3'/>
+ <tbody>
+ <row>
+ <entry><symbol>CapNotLast</symbol></entry>
+ <entry>thin</entry>
+ <entry>The results are device dependent,
+ but the desired effect is that nothing is drawn.</entry>
+ </row>
+ <row>
+ <entry><symbol>CapButt</symbol></entry>
+ <entry>thin</entry>
+ <entry>The results are device dependent,
+ but the desired effect is that a single pixel is drawn.</entry>
+ </row>
+ <row>
+ <entry><symbol>CapRound</symbol></entry>
+ <entry>thin</entry>
+ <entry>The results are the same as for
+ <symbol>CapButt</symbol> /thin.</entry>
+ </row>
+ <row>
+ <entry><symbol>CapProjecting</symbol></entry>
+ <entry>thin</entry>
+ <entry>The results are the same as for
+ <symbol>CapButt</symbol> /thin.</entry>
+ </row>
+ <row>
+ <entry><symbol>CapButt</symbol></entry>
+ <entry>wide</entry>
+ <entry>Nothing is drawn.</entry>
+ </row>
+ <row>
+ <entry><symbol>CapRound</symbol></entry>
+ <entry>wide</entry>
+ <entry>The closed path is a circle, centered at the endpoint, and
+ with the diameter equal to the line-width.</entry>
+ </row>
+ <row>
+ <entry><symbol>CapProjecting</symbol></entry>
+ <entry>wide</entry>
+ <entry>The closed path is a square, aligned with the coordinate axes, centered at the
+ endpoint, and with the sides equal to the line-width.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+For a line with coincident endpoints (x1=x2, y1=y2),
+when the join-style is applied at one or both endpoints,
+the effect is as if the line was removed from the overall path.
+However, if the total path consists of or is reduced to a single point joined
+with itself, the effect is the same as when the cap-style is applied at both
+endpoints.
+</para>
+<para>
+<!-- .LP -->
+The tile/stipple represents an infinite two-dimensional plane,
+with the tile/stipple replicated in all dimensions.
+When that plane is superimposed on the drawable
+for use in a graphics operation, the upper-left corner
+of some instance of the tile/stipple is at the coordinates within
+the drawable specified by the tile/stipple origin.
+The tile/stipple and clip origins are interpreted relative to the
+origin of whatever destination drawable is specified in a graphics
+request.
+The tile pixmap must have the same root and depth as the GC,
+or a
+<errorname>BadMatch</errorname>
+error results.
+The stipple pixmap must have depth one and must have the same root as the
+GC, or a
+<errorname>BadMatch</errorname>
+error results.
+For stipple operations where the fill-style is
+<symbol>FillStippled</symbol>
+but not
+<symbol>FillOpaqueStippled</symbol>,
+the stipple pattern is tiled in a
+single plane and acts as an additional clip mask to be ANDed with the clip-mask.
+Although some sizes may be faster to use than others,
+any size pixmap can be used for tiling or stippling.
+</para>
+
+<para>
+<!-- .LP -->
+The fill-style defines the contents of the source for line, text, and
+fill requests.
+For all text and fill requests (for example,
+<function>XDrawText</function>,
+<function>XDrawText16</function>,
+<function>XFillRectangle</function>,
+<function>XFillPolygon</function>,
+and
+<function>XFillArc</function>);
+for line requests
+with line-style
+<symbol>LineSolid</symbol>
+(for example,
+<function>XDrawLine</function>,
+<function>XDrawSegments</function>,
+<function>XDrawRectangle</function>,
+<function>XDrawArc</function>);
+and for the even dashes for line requests with line-style
+<symbol>LineOnOffDash</symbol>
+or
+<symbol>LineDoubleDash</symbol>,
+the following apply:
+</para>
+
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <tbody>
+ <row>
+ <entry><symbol>FillSolid</symbol></entry>
+ <entry>Foreground</entry>
+ </row>
+ <row>
+ <entry><symbol>FillTiled</symbol></entry>
+ <entry>Tile</entry>
+ </row>
+ <row>
+ <entry><symbol>FillOpaqueStippled</symbol></entry>
+ <entry>A tile with the same width and height as stipple,
+ but with background everywhere stipple has a zero
+ and with foreground everywhere stipple has a one</entry>
+ </row>
+ <row>
+ <entry><symbol>FillStippled</symbol></entry>
+ <entry>Foreground masked by stipple</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+When drawing lines with line-style
+<symbol>LineDoubleDash</symbol>,
+the odd dashes are controlled by the fill-style in the following manner:
+</para>
+
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <tbody>
+ <row>
+ <entry><symbol>FillSolid</symbol></entry>
+ <entry>Background</entry>
+ </row>
+ <row>
+ <entry><symbol>FillTiled</symbol></entry>
+ <entry>Same as for even dashes</entry>
+ </row>
+ <row>
+ <entry><symbol>FillOpaqueStippled</symbol></entry>
+ <entry>Same as for even dashes</entry>
+ </row>
+ <row>
+ <entry><symbol>FillStippled</symbol></entry>
+ <entry>Background masked by stipple</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+Storing a pixmap in a GC might or might not result in a copy
+being made.
+If the pixmap is later used as the destination for a graphics request,
+the change might or might not be reflected in the GC.
+If the pixmap is used simultaneously in a graphics request both as
+a destination and as a tile or stipple,
+the results are undefined.
+</para>
+<para>
+<!-- .LP -->
+For optimum performance,
+you should draw as much as possible with the same GC
+(without changing its components).
+The costs of changing GC components relative to using different GCs
+depend on the display hardware and the server implementation.
+It is quite likely that some amount of GC information will be
+cached in display hardware and that such hardware can only cache a small number
+of GCs.
+</para>
+<para>
+<!-- .LP -->
+The dashes value is actually a simplified form of the
+more general patterns that can be set with
+<function>XSetDashes</function>.
+Specifying a
+value of N is equivalent to specifying the two-element list [N, N] in
+<function>XSetDashes</function>.
+The value must be nonzero,
+or a
+<errorname>BadValue</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+The clip-mask restricts writes to the destination drawable.
+If the clip-mask is set to a pixmap,
+it must have depth one and have the same root as the GC,
+or a
+<errorname>BadMatch</errorname>
+error results.
+If clip-mask is set to
+<symbol>None</symbol>,
+the pixels are always drawn regardless of the clip origin.
+The clip-mask also can be set by calling the
+<function>XSetClipRectangles</function>
+or
+<function>XSetRegion</function>
+functions.
+Only pixels where the clip-mask has a bit set to 1 are drawn.
+Pixels are not drawn outside the area covered by the clip-mask
+or where the clip-mask has a bit set to 0.
+The clip-mask affects all graphics requests.
+The clip-mask does not clip sources.
+The clip-mask origin is interpreted relative to the origin of whatever
+destination drawable is specified in a graphics request.
+</para>
+<para>
+<!-- .LP -->
+You can set the subwindow-mode to
+<symbol>ClipByChildren</symbol>
+or
+<symbol>IncludeInferiors</symbol>.
+For
+<symbol>ClipByChildren</symbol>,
+both source and destination windows are
+additionally clipped by all viewable
+<symbol>InputOutput</symbol>
+children.
+For
+<symbol>IncludeInferiors</symbol>,
+neither source nor destination window is clipped by inferiors.
+This will result in including subwindow contents in the source
+and drawing through subwindow boundaries of the destination.
+The use of
+<symbol>IncludeInferiors</symbol>
+on a window of one depth with mapped
+inferiors of differing depth is not illegal, but the semantics are
+undefined by the core protocol.
+</para>
+<para>
+<!-- .LP -->
+The fill-rule defines what pixels are inside (drawn) for
+paths given in
+<function>XFillPolygon</function>
+requests and can be set to
+<symbol>EvenOddRule</symbol>
+or
+<symbol>WindingRule</symbol>.
+For
+<symbol>EvenOddRule</symbol>,
+a point is inside if
+an infinite ray with the point as origin crosses the path an odd number
+of times.
+For
+<symbol>WindingRule</symbol>,
+a point is inside if an infinite ray with the
+point as origin crosses an unequal number of clockwise and
+counterclockwise directed path segments.
+A clockwise directed path segment is one that crosses the ray from left to
+right as observed from the point.
+A counterclockwise segment is one that crosses the ray from right to left
+as observed from the point.
+The case where a directed line segment is coincident with the ray is
+uninteresting because you can simply choose a different ray that is not
+coincident with a segment.
+</para>
+<para>
+<!-- .LP -->
+For both
+<symbol>EvenOddRule</symbol>
+and
+<symbol>WindingRule</symbol>,
+a point is infinitely small,
+and the path is an infinitely thin line.
+A pixel is inside if the center point of the pixel is inside
+and the center point is not on the boundary.
+If the center point is on the boundary,
+the pixel is inside if and only if the polygon interior is immediately to
+its right (x increasing direction).
+Pixels with centers on a horizontal edge are a special case
+and are inside if and only if the polygon interior is immediately below
+(y increasing direction).
+</para>
+<para>
+<!-- .LP -->
+The arc-mode controls filling in the
+<function>XFillArcs</function>
+function and can be set to
+<symbol>ArcPieSlice</symbol>
+or
+<symbol>ArcChord</symbol>.
+For
+<symbol>ArcPieSlice</symbol>,
+the arcs are pie-slice filled.
+For
+<symbol>ArcChord</symbol>,
+the arcs are chord filled.
+</para>
+<para>
+<!-- .LP -->
+The graphics-exposure flag controls
+<symbol>GraphicsExpose</symbol>
+event generation
+for
+<function>XCopyArea</function>
+and
+<function>XCopyPlane</function>
+requests (and any similar requests defined by extensions).
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create a new GC that is usable on a given screen with a
+depth of drawable, use
+<function>XCreateGC</function>.
+<indexterm><primary>Graphics context</primary><secondary>initializing</secondary></indexterm>
+<indexterm significance="preferred"><primary>XCreateGC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreategc'>
+<funcprototype>
+ <funcdef>GC <function>XCreateGC</function></funcdef>
+ <paramdef>Display <parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> valuemask</parameter></paramdef>
+ <paramdef>XGCValues *<parameter>values</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+<!-- .ds Vm set using the information in the specified values structure -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>valuemask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which components in the GC are to be (Vm.
+This argument is the bitwise inclusive OR of zero or more of the valid
+GC component mask bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>values</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies any values as specified by the valuemask.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreateGC</function>
+function creates a graphics context and returns a GC.
+The GC can be used with any destination drawable having the same root
+and depth as the specified drawable.
+Use with other drawables results in a
+<errorname>BadMatch</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreateGC</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadDrawable</errorname>,
+<errorname>BadFont</errorname>,
+<errorname>BadMatch</errorname>,
+<errorname>BadPixmap</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To copy components from a source GC to a destination GC, use
+<function>XCopyGC</function>.
+<indexterm significance="preferred"><primary>XCopyGC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcopygc'>
+<funcprototype>
+ <funcdef><function>XCopyGC</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GCsrc,<parameter> dest</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> valuemask</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the components of the source GC.
+<!-- .ds Vm copied to the destination GC -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>valuemask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which components in the GC are to be (Vm.
+This argument is the bitwise inclusive OR of zero or more of the valid
+GC component mask bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the destination GC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCopyGC</function>
+function copies the specified components from the source GC
+to the destination GC.
+The source and destination GCs must have the same root and depth,
+or a
+<errorname>BadMatch</errorname>
+error results.
+The valuemask specifies which component to copy, as for
+<function>XCreateGC</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XCopyGC</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadMatch</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To change the components in a given GC, use
+<function>XChangeGC</function>.
+<indexterm significance="preferred"><primary>XChangeGC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xchangegc'>
+<funcprototype>
+ <funcdef><function>XChangeGC</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> valuemask</parameter></paramdef>
+ <paramdef>XGCValues<parameter> *values</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Vm changed using information in the specified values structure -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>valuemask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which components in the GC are to be (Vm.
+This argument is the bitwise inclusive OR of zero or more of the valid
+GC component mask bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>values</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies any values as specified by the valuemask.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XChangeGC</function>
+function changes the components specified by valuemask for
+the specified GC.
+The values argument contains the values to be set.
+The values and restrictions are the same as for
+<function>XCreateGC</function>.
+Changing the clip-mask overrides any previous
+<function>XSetClipRectangles</function>
+request on the context.
+Changing the dash-offset or dash-list
+overrides any previous
+<function>XSetDashes</function>
+request on the context.
+The order in which components are verified and altered is server dependent.
+If an error is generated, a subset of the components may have been altered.
+</para>
+<para>
+<!-- .LP -->
+<function>XChangeGC</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadFont</errorname>,
+<errorname>BadGC</errorname>,
+<errorname>BadMatch</errorname>,
+<errorname>BadPixmap</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain components of a given GC, use
+<function>XGetGCValues</function>.
+<indexterm significance="preferred"><primary>XGetGCValues</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetgcvalues'>
+<funcprototype>
+ <funcdef>Status <function>XGetGCValues</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> valuemask</parameter></paramdef>
+ <paramdef>XGCValues<parameter> *values_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Vm returned in the values_return argument -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>valuemask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which components in the GC are to be (Vm.
+This argument is the bitwise inclusive OR of zero or more of the valid
+GC component mask bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>values_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the GC values in the specified
+<structname>XGCValues</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetGCValues</function>
+function returns the components specified by valuemask for the specified GC.
+If the valuemask contains a valid set of GC mask bits
+(<symbol>GCFunction</symbol>,
+<symbol>GCPlaneMask</symbol>,
+<symbol>GCForeground</symbol>,
+<symbol>GCBackground</symbol>,
+<symbol>GCLineWidth</symbol>,
+<symbol>GCLineStyle</symbol>,
+<symbol>GCCapStyle</symbol>,
+<symbol>GCJoinStyle</symbol>,
+<symbol>GCFillStyle</symbol>,
+<symbol>GCFillRule</symbol>,
+<symbol>GCTile</symbol>,
+<symbol>GCStipple</symbol>,
+<symbol>GCTileStipXOrigin</symbol>,
+<symbol>GCTileStipYOrigin</symbol>,
+<symbol>GCFont</symbol>,
+<symbol>GCSubwindowMode</symbol>,
+<symbol>GCGraphicsExposures</symbol>,
+<symbol>GCClipXOrigin</symbol>,
+<symbol>GCClipYOrigin</symbol>,
+<symbol>GCDashOffset</symbol>,
+or
+<symbol>GCArcMode</symbol>)
+and no error occurs,
+<function>XGetGCValues</function>
+sets the requested components in values_return and returns a nonzero status.
+Otherwise, it returns a zero status.
+Note that the clip-mask and dash-list (represented by the
+<symbol>GCClipMask</symbol>
+and
+<symbol>GCDashList</symbol>
+bits, respectively, in the valuemask)
+cannot be requested.
+Also note that an invalid resource ID (with one or more of the three
+most significant bits set to 1) will be returned for
+<symbol>GCFont</symbol>,
+<symbol>GCTile</symbol>,
+and
+<symbol>GCStipple</symbol>
+if the component has never been explicitly set by the client.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To free a given GC, use
+<function>XFreeGC</function>.
+<indexterm significance="preferred"><primary>XFreeGC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfreegc'>
+<funcprototype>
+ <funcdef><function>XFreeGC</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreeGC</function>
+function destroys the specified GC as well as all the associated storage.
+</para>
+<para>
+<!-- .LP -->
+<function>XFreeGC</function>
+can generate a
+<errorname>BadGC</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the
+<type>GContext</type>
+resource ID for a given GC, use
+<function>XGContextFromGC</function>.
+<indexterm significance="preferred"><primary>XGContextFromGC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgcontextfromgc'>
+<funcprototype>
+ <funcdef>GContext <function>XGContextFromGC</function></funcdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<!-- .ds Gc for which you want the resource ID -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC (Gc.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+Xlib usually defers sending changes to the components of a GC to the server
+until a graphics function is actually called with that GC.
+This permits batching of component changes into a single server request.
+In some circumstances, however, it may be necessary for the client
+to explicitly force sending the changes to the server.
+An example might be when a protocol extension uses the GC indirectly,
+in such a way that the extension interface cannot know what GC will be used.
+To force sending GC component changes, use
+<function>XFlushGC</function>.
+<indexterm significance="preferred"><primary>XFlushGC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xflushgc'>
+<funcprototype>
+ <funcdef>void <function>XFlushGC</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+</para>
+</sect1>
+<sect1 id="Using_Graphics_Context_Convenience_Routines">
+<title>Using Graphics Context Convenience Routines</title>
+<!-- .XS -->
+<!-- (SN Using Graphics Context Convenience Routines -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This section discusses how to set the:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Foreground, background, plane mask, or function components
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Line attributes and dashes components
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Fill style and fill rule components
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Fill tile and stipple components
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Font component
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Clip region component
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Arc mode, subwindow mode, and graphics exposure components
+ </para>
+ </listitem>
+</itemizedlist>
+<sect2 id="Setting_the_Foreground_Background_Function_or_Plane_Mask">
+<title>Setting the Foreground, Background, Function, or Plane Mask</title>
+<!-- .XS -->
+<!-- (SN Setting the Foreground, Background, Function, or Plane Mask -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To set the foreground, background, plane mask, and function components
+for a given GC, use
+<function>XSetState</function>.
+<indexterm significance="preferred"><primary>XSetState</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetstate'>
+<funcprototype>
+ <funcdef><function>XSetState</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>unsignedlongforeground,<parameter> background</parameter></paramdef>
+ <paramdef>int<parameter> function</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> plane_mask</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>foreground</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the foreground you want to set for the specified GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>background</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the background you want to set for the specified GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>function</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the function you want to set for the specified GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>plane_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the plane mask.
+<!-- .\" *** JIM: NEED MORE INFO FOR THIS. *** -->
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XSetState</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the foreground of a given GC, use
+<function>XSetForeground</function>.
+<indexterm significance="preferred"><primary>XSetForeground</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetforeground'>
+<funcprototype>
+ <funcdef><function>XSetForeground</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> foreground</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>foreground</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the foreground you want to set for the specified GC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XSetForeground</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadGC</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the background of a given GC, use
+<function>XSetBackground</function>.
+<indexterm significance="preferred"><primary>XSetBackground</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetbackground'>
+<funcprototype>
+ <funcdef><function>XSetBackground</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> background</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>background</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the background you want to set for the specified GC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XSetBackground</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadGC</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the display function in a given GC, use
+<function>XSetFunction</function>.
+<indexterm significance="preferred"><primary>XSetFunction</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetfunction'>
+<funcprototype>
+ <funcdef><function>XSetFunction</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>int<parameter> function</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>function</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the function you want to set for the specified GC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XSetFunction</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the plane mask of a given GC, use
+<function>XSetPlaneMask</function>.
+<indexterm significance="preferred"><primary>XSetPlaneMask</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetplanemask'>
+<funcprototype>
+ <funcdef><function>XSetPlaneMask</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> plane_mask</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>plane_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the plane mask.
+<!-- .\" *** JIM: NEED MORE INFO FOR THIS. *** -->
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XSetPlaneMask</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadGC</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Setting_the_Line_Attributes_and_Dashes">
+<title>Setting the Line Attributes and Dashes</title>
+<!-- .XS -->
+<!-- (SN Setting the Line Attributes and Dashes -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To set the line drawing components of a given GC, use
+<function>XSetLineAttributes</function>.
+<indexterm significance="preferred"><primary>XSetLineAttributes</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetlineattributes'>
+<funcprototype>
+ <funcdef><function>XSetLineAttributes</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>unsignedint<parameter> line_width</parameter></paramdef>
+ <paramdef>int<parameter> line_style</parameter></paramdef>
+ <paramdef>int<parameter> cap_style</parameter></paramdef>
+ <paramdef>int<parameter> join_style</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>line_width</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the line-width you want to set for the specified GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>line_style</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the line-style you want to set for the specified GC.
+You can pass
+<symbol>LineSolid</symbol>,
+<symbol>LineOnOffDash</symbol>,
+or
+<symbol>LineDoubleDash</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>cap_style</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the line-style and cap-style you want to set for the specified GC.
+You can pass
+<symbol>CapNotLast</symbol>,
+<symbol>CapButt</symbol>,
+<symbol>CapRound</symbol>,
+or
+<symbol>CapProjecting</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>join_style</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the line join-style you want to set for the specified GC.
+You can pass
+<symbol>JoinMiter</symbol>,
+<symbol>JoinRound</symbol>,
+or
+<symbol>JoinBevel</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XSetLineAttributes</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the dash-offset and dash-list for dashed line styles of a given GC, use
+<function>XSetDashes</function>.
+<indexterm significance="preferred"><primary>XSetDashes</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetdashes'>
+<funcprototype>
+ <funcdef><function>XSetDashes</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>int<parameter> dash_offset</parameter></paramdef>
+ <paramdef>char<parameter> dash_list[]</parameter></paramdef>
+ <paramdef>int<parameter> n</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dash_offset</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the phase of the pattern for the dashed line-style you want to set
+for the specified GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dash_list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the dash-list for the dashed line-style
+you want to set for the specified GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>n</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of elements in dash_list.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetDashes</function>
+function sets the dash-offset and dash-list attributes for dashed line styles
+in the specified GC.
+There must be at least one element in the specified dash_list,
+or a
+<errorname>BadValue</errorname>
+error results.
+The initial and alternating elements (second, fourth, and so on)
+of the dash_list are the even dashes, and
+the others are the odd dashes.
+Each element specifies a dash length in pixels.
+All of the elements must be nonzero,
+or a
+<errorname>BadValue</errorname>
+error results.
+Specifying an odd-length list is equivalent to specifying the same list
+concatenated with itself to produce an even-length list.
+</para>
+<para>
+<!-- .LP -->
+The dash-offset defines the phase of the pattern,
+specifying how many pixels into the dash-list the pattern
+should actually begin in any single graphics request.
+Dashing is continuous through path elements combined with a join-style
+but is reset to the dash-offset between each sequence of joined lines.
+</para>
+<para>
+<!-- .LP -->
+The unit of measure for dashes is the same for the ordinary coordinate system.
+Ideally, a dash length is measured along the slope of the line, but implementations
+are only required to match this ideal for horizontal and vertical lines.
+Failing the ideal semantics, it is suggested that the length be measured along the
+major axis of the line.
+The major axis is defined as the x axis for lines drawn at an angle of between
+&minus;45 and +45 degrees or between 135 and 225 degrees from the x axis.
+For all other lines, the major axis is the y axis.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetDashes</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Setting_the_Fill_Style_and_Fill_Rule_">
+<title>Setting the Fill Style and Fill Rule </title>
+<!-- .XS -->
+<!-- (SN Setting the Fill Style and Fill Rule -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To set the fill-style of a given GC, use
+<function>XSetFillStyle</function>.
+<indexterm significance="preferred"><primary>XSetFillStyle</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetfillstyle'>
+<funcprototype>
+ <funcdef><function>XSetFillStyle</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>int<parameter> fill_style</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>fill_style</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the fill-style you want to set for the specified GC.
+You can pass
+<symbol>FillSolid</symbol>,
+<symbol>FillTiled</symbol>,
+<symbol>FillStippled</symbol>,
+or
+<symbol>FillOpaqueStippled</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XSetFillStyle</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the fill-rule of a given GC, use
+<function>XSetFillRule</function>.
+<indexterm significance="preferred"><primary>XSetFillRule</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetfillrule'>
+<funcprototype>
+ <funcdef><function>XSetFillRule</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>int<parameter> fill_rule</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>fill_rule</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the fill-rule you want to set for the specified GC.
+You can pass
+<symbol>EvenOddRule</symbol>
+or
+<symbol>WindingRule</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XSetFillRule</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Setting_the_Fill_Tile_and_Stipple_">
+<title>Setting the Fill Tile and Stipple </title>
+<!-- .XS -->
+<!-- (SN Setting the Fill Tile and Stipple -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Some displays have hardware support for tiling or
+stippling with patterns of specific sizes.
+Tiling and stippling operations that restrict themselves to those specific
+sizes run much faster than such operations with arbitrary size patterns.
+Xlib provides functions that you can use to determine the best size,
+tile, or stipple for the display
+as well as to set the tile or stipple shape and the tile or stipple origin.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the best size of a tile, stipple, or cursor, use
+<function>XQueryBestSize</function>.
+<indexterm significance="preferred"><primary>XQueryBestSize</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xquerybestsize'>
+<funcprototype>
+ <funcdef>Status <function>XQueryBestSize</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> class</parameter></paramdef>
+ <paramdef>Drawable<parameter> which_screen</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>class</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the class that you are interested in.
+You can pass
+<symbol>TileShape</symbol>,
+<symbol>CursorShape</symbol>,
+or
+<symbol>StippleShape</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>which_screen</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies any drawable on the screen.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the width and height of the object best supported
+by the display hardware.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XQueryBestSize</function>
+function returns the best or closest size to the specified size.
+For
+<symbol>CursorShape</symbol>,
+this is the largest size that can be fully displayed on the screen specified by
+which_screen.
+For
+<symbol>TileShape</symbol>,
+this is the size that can be tiled fastest.
+For
+<symbol>StippleShape</symbol>,
+this is the size that can be stippled fastest.
+For
+<symbol>CursorShape</symbol>,
+the drawable indicates the desired screen.
+For
+<symbol>TileShape</symbol>
+and
+<symbol>StippleShape</symbol>,
+the drawable indicates the screen and possibly the window class and depth.
+An
+<symbol>InputOnly</symbol>
+window cannot be used as the drawable for
+<symbol>TileShape</symbol>
+or
+<symbol>StippleShape</symbol>,
+or a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XQueryBestSize</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadMatch</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the best fill tile shape, use
+<function>XQueryBestTile</function>.
+<indexterm significance="preferred"><primary>XQueryBestTile</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xquerybesttile'>
+<funcprototype>
+ <funcdef>Status <function>XQueryBestTile</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> which_screen</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>which_screen</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies any drawable on the screen.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the width and height of the object best supported
+by the display hardware.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XQueryBestTile</function>
+function returns the best or closest size, that is, the size that can be
+tiled fastest on the screen specified by which_screen.
+The drawable indicates the screen and possibly the window class and depth.
+If an
+<symbol>InputOnly</symbol>
+window is used as the drawable, a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XQueryBestTile</function>
+can generate
+<errorname>BadDrawable</errorname>
+and
+<errorname>BadMatch</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the best stipple shape, use
+<function>XQueryBestStipple</function>.
+<indexterm significance="preferred"><primary>XQueryBestStipple</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xquerybeststipple'>
+<funcprototype>
+ <funcdef>Status <function>XQueryBestStipple</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> which_screen</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>which_screen</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies any drawable on the screen.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the width and height of the object best supported
+by the display hardware.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XQueryBestStipple</function>
+function returns the best or closest size, that is, the size that can be
+stippled fastest on the screen specified by which_screen.
+The drawable indicates the screen and possibly the window class and depth.
+If an
+<symbol>InputOnly</symbol>
+window is used as the drawable, a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XQueryBestStipple</function>
+can generate
+<errorname>BadDrawable</errorname>
+and
+<errorname>BadMatch</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the fill tile of a given GC, use
+<function>XSetTile</function>.
+<indexterm significance="preferred"><primary>XSetTile</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsettile'>
+<funcprototype>
+ <funcdef><function>XSetTile</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>Pixmap<parameter> tile</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>tile</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the fill tile you want to set for the specified GC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The tile and GC must have the same depth,
+or a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetTile</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+<errorname>BadMatch</errorname>,
+and
+<errorname>BadPixmap</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the stipple of a given GC, use
+<function>XSetStipple</function>.
+<indexterm significance="preferred"><primary>XSetStipple</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetstipple'>
+<funcprototype>
+ <funcdef><function>XSetStipple</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>Pixmap<parameter> stipple</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>stipple</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the stipple you want to set for the specified GC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The stipple must have a depth of one,
+or a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetStipple</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+<errorname>BadMatch</errorname>,
+and
+<errorname>BadPixmap</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the tile or stipple origin of a given GC, use
+<function>XSetTSOrigin</function>.
+<indexterm significance="preferred"><primary>XSetTSOrigin</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsettsorigin'>
+<funcprototype>
+ <funcdef><function>XSetTSOrigin</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intts_x_origin,<parameter> ts_y_origin</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ts_x_origin</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ts_y_origin</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates of the tile and stipple origin.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+When graphics requests call for tiling or stippling,
+the parent's origin will be interpreted relative to whatever destination
+drawable is specified in the graphics request.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetTSOrigin</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadGC</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Setting_the_Current_Font_">
+<title>Setting the Current Font </title>
+<!-- .XS -->
+<!-- (SN Setting the Current Font -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To set the current font of a given GC, use
+<function>XSetFont</function>.
+<indexterm significance="preferred"><primary>XSetFont</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetfont'>
+<funcprototype>
+ <funcdef><function>XSetFont</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>Font<parameter> font</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XSetFont</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadFont</errorname>,
+and
+<errorname>BadGC</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Setting_the_Clip_Region">
+<title>Setting the Clip Region</title>
+<!-- .XS -->
+<!-- (SN Setting the Clip Region -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set the clip-origin
+and the clip-mask or set the clip-mask to a list of rectangles.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the clip-origin of a given GC, use
+<function>XSetClipOrigin</function>.
+<indexterm significance="preferred"><primary>XSetClipOrigin</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetcliporigin'>
+<funcprototype>
+ <funcdef><function>XSetClipOrigin</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intclip_x_origin,<parameter> clip_y_origin</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>clip_x_origin</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>clip_y_origin</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates of the clip-mask origin.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The clip-mask origin is interpreted relative to the origin of whatever
+destination drawable is specified in the graphics request.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetClipOrigin</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadGC</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the clip-mask of a given GC to the specified pixmap, use
+<function>XSetClipMask</function>.
+<indexterm significance="preferred"><primary>XSetClipMask</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetclipmask'>
+<funcprototype>
+ <funcdef><function>XSetClipMask</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>Pixmap<parameter> pixmap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pixmap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the pixmap or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If the clip-mask is set to
+<symbol>None</symbol>,
+the pixels are always drawn (regardless of the clip-origin).
+</para>
+<para>
+<!-- .LP -->
+<function>XSetClipMask</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+<errorname>BadMatch</errorname>,
+and
+<errorname>BadPixmap</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the clip-mask of a given GC to the specified list of rectangles, use
+<function>XSetClipRectangles</function>.
+<indexterm significance="preferred"><primary>XSetClipRectangles</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetcliprectangles'>
+<funcprototype>
+ <funcdef><function>XSetClipRectangles</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intclip_x_origin,<parameter> clip_y_origin</parameter></paramdef>
+ <paramdef>XRectangle<parameter> rectangles[]</parameter></paramdef>
+ <paramdef>int<parameter> n</parameter></paramdef>
+ <paramdef>int<parameter> ordering</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>clip_x_origin</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>clip_y_origin</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates of the clip-mask origin.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rectangles</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of rectangles that define the clip-mask.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>n</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of rectangles.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ordering</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the ordering relations on the rectangles.
+You can pass
+<symbol>Unsorted</symbol>,
+<symbol>YSorted</symbol>,
+<symbol>YXSorted</symbol>,
+or
+<symbol>YXBanded</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetClipRectangles</function>
+function changes the clip-mask in the specified GC
+to the specified list of rectangles and sets the clip origin.
+The output is clipped to remain contained within the
+rectangles.
+The clip-origin is interpreted relative to the origin of
+whatever destination drawable is specified in a graphics request.
+The rectangle coordinates are interpreted relative to the clip-origin.
+The rectangles should be nonintersecting, or the graphics results will be
+undefined.
+Note that the list of rectangles can be empty,
+which effectively disables output.
+This is the opposite of passing
+<symbol>None</symbol>
+as the clip-mask in
+<function>XCreateGC</function>,
+<function>XChangeGC</function>,
+and
+<function>XSetClipMask</function>.
+</para>
+<para>
+<!-- .LP -->
+If known by the client, ordering relations on the rectangles can be
+specified with the ordering argument.
+This may provide faster operation
+by the server.
+If an incorrect ordering is specified, the X server may generate a
+<errorname>BadMatch</errorname>
+error, but it is not required to do so.
+If no error is generated, the graphics
+results are undefined.
+<symbol>Unsorted</symbol>
+means the rectangles are in arbitrary order.
+<symbol>YSorted</symbol>
+means that the rectangles are nondecreasing in their Y origin.
+<symbol>YXSorted</symbol>
+additionally constrains
+<symbol>YSorted</symbol>
+order in that all
+rectangles with an equal Y origin are nondecreasing in their X
+origin.
+<symbol>YXBanded</symbol>
+additionally constrains
+<symbol>YXSorted</symbol>
+by requiring that,
+for every possible Y scanline, all rectangles that include that
+scanline have an identical Y origins and Y extents.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetClipRectangles</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+<errorname>BadMatch</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+Xlib provides a set of basic functions for performing
+region arithmetic.
+For information about these functions,
+see section 16.5.
+</para>
+</sect2>
+<sect2 id="Setting_the_Arc_Mode_Subwindow_Mode_and_Graphics_Exposure_">
+<title>Setting the Arc Mode, Subwindow Mode, and Graphics Exposure </title>
+<!-- .XS -->
+<!-- (SN Setting the Arc Mode, Subwindow Mode, and Graphics Exposure -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To set the arc mode of a given GC, use
+<function>XSetArcMode</function>.
+<indexterm significance="preferred"><primary>XSetArcMode</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetarcmode'>
+<funcprototype>
+ <funcdef><function>XSetArcMode</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>int<parameter> arc_mode</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>arc_mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the arc mode.
+You can pass
+<symbol>ArcChord</symbol>
+or
+<symbol>ArcPieSlice</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XSetArcMode</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the subwindow mode of a given GC, use
+<function>XSetSubwindowMode</function>.
+<indexterm significance="preferred"><primary>XSetSubwindowMode</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetsubwindowmode'>
+<funcprototype>
+ <funcdef><function>XSetSubwindowMode</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>int<parameter> subwindow_mode</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>subwindow_mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the subwindow mode.
+You can pass
+<symbol>ClipByChildren</symbol>
+or
+<symbol>IncludeInferiors</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XSetSubwindowMode</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the graphics-exposures flag of a given GC, use
+<function>XSetGraphicsExposures</function>.
+<indexterm significance="preferred"><primary>XSetGraphicsExposures</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetgraphicsexposures'>
+<funcprototype>
+ <funcdef><function>XSetGraphicsExposures</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>Bool<parameter> graphics_exposures</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>graphics_exposures</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value that indicates whether you want
+<symbol>GraphicsExpose</symbol>
+and
+<symbol>NoExpose</symbol>
+events to be reported when calling
+<function>XCopyArea</function>
+and
+<function>XCopyPlane</function>
+with this GC.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XSetGraphicsExposures</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+<!-- .bp -->
+
+</para>
+</sect2>
+</sect1>
+</chapter>
diff --git a/libX11/specs/libX11/CH08.xml b/libX11/specs/libX11/CH08.xml
index 6cd6679f2..3d69b1420 100644
--- a/libX11/specs/libX11/CH08.xml
+++ b/libX11/specs/libX11/CH08.xml
@@ -1,5966 +1,5966 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<chapter id="graphics_functions">
-<title>Graphics Functions</title>
-<para>
-Once you have established a connection to a display, you can use the Xlib graphics functions to:
-</para>
-<itemizedlist>
- <listitem><para>Clear and copy areas</para></listitem>
- <listitem><para>Draw points, lines, rectangles, and arcs</para></listitem>
- <listitem><para>Fill areas</para></listitem>
- <listitem><para>Manipulate fonts</para></listitem>
- <listitem><para>Draw text</para></listitem>
- <listitem><para>Transfer images between clients and the server</para></listitem>
-</itemizedlist>
-<para>
-If the same drawable and GC is used for each call, Xlib batches back-to-back
-calls to XDrawPoint, XDrawLine, XDrawRectangle, XFillArc, and XFillRectangle.
-Note that this reduces the total number of requests sent to the server.
-</para>
-<sect1 id="Clearing_Areas">
-<title>Clearing Areas</title>
-<!-- .XS -->
-<!-- (SN Clearing Areas -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to clear an area or the entire window.
-Because pixmaps do not have defined backgrounds,
-they cannot be filled by using the functions described in this section.
-Instead, to accomplish an analogous operation on a pixmap,
-you should use
-<function>XFillRectangle</function>,
-which sets the pixmap to a known value.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To clear a rectangular area of a given window, use
-<function>XClearArea</function>.
-<indexterm><primary>Areas</primary><secondary>clearing</secondary></indexterm>
-<indexterm><primary>Clearing</primary><secondary>areas</secondary></indexterm>
-<indexterm significance="preferred"><primary>XClearArea</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XClearArea</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>Bool<parameter> exposures</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
-<!-- .ds Xy , which are relative to the origin of the window \ -->
-and specify the upper-left corner of the rectangle
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
-<!-- .ds Wh , which are the dimensions of the rectangle -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>exposures</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value that indicates if
-<symbol>Expose</symbol>
-events are to be generated.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XClearArea</function>
-function paints a rectangular area in the specified window according to the
-specified dimensions with the window's background pixel or pixmap.
-The subwindow-mode effectively is
-<symbol>ClipByChildren</symbol>.
-If width is zero, it
-is replaced with the current width of the window minus x.
-If height is
-zero, it is replaced with the current height of the window minus y.
-If the window has a defined background tile,
-the rectangle clipped by any children is filled with this tile.
-If the window has
-background
-<symbol>None</symbol>,
-the contents of the window are not changed.
-In either
-case, if exposures is
-<symbol>True</symbol>,
-one or more
-<symbol>Expose</symbol>
-events are generated for regions of the rectangle that are either visible or are
-being retained in a backing store.
-If you specify a window whose class is
-<symbol>InputOnly</symbol>,
-a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XClearArea</function>
-can generate
-<errorname>BadMatch</errorname>,
-<errorname>BadValue</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To clear the entire area in a given window, use
-<function>XClearWindow</function>.
-<indexterm><primary>Window</primary><secondary>clearing</secondary></indexterm>
-<indexterm><primary>Clearing</primary><secondary>windows</secondary></indexterm>
-<indexterm significance="preferred"><primary>XClearWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XClearWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XClearWindow</function>
-function clears the entire area in the specified window and is
-equivalent to
-<function>XClearArea</function>
-(display, w, 0, 0, 0, 0,
-<symbol>False</symbol>).
-If the window has a defined background tile, the rectangle is tiled with a
-plane-mask of all ones and
-<symbol>GXcopy</symbol>
-function.
-If the window has
-background
-<symbol>None</symbol>,
-the contents of the window are not changed.
-If you specify a window whose class is
-<symbol>InputOnly</symbol>,
-a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XClearWindow</function>
-can generate
-<errorname>BadMatch</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect1>
-<sect1 id="Copying_Areas">
-<title>Copying Areas</title>
-<!-- .XS -->
-<!-- (SN Copying Areas -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to copy an area or a bit plane.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To copy an area between drawables of the same
-root and depth, use
-<function>XCopyArea</function>.
-<indexterm><primary>Areas</primary><secondary>copying</secondary></indexterm>
-<indexterm><primary>Copying</primary><secondary>areas</secondary></indexterm>
-<indexterm significance="preferred"><primary>XCopyArea</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XCopyArea</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawablesrc,<parameter> dest</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intsrc_x,<parameter> src_y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>intdest_x,<parameter> dest_y</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest</emphasis>
- </term>
- <listitem>
- <para>
-Specify the source and destination rectangles to be combined.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src_x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src_y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates,
-which are relative to the origin of the source rectangle
-and specify its upper-left corner.
-<!-- .ds Wh , which are the dimensions of both the source \ -->
-and destination rectangles
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
-<!-- .ds Dx , which are relative to the origin of the destination rectangle \ -->
-and specify its upper-left corner
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Dx.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCopyArea</function>
-function combines the specified rectangle of src with the specified rectangle
-of dest.
-The drawables must have the same root and depth,
-or a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-If regions of the source rectangle are obscured and have not been
-retained in backing store
-or if regions outside the boundaries of the source drawable are specified,
-those regions are not copied.
-Instead, the
-following occurs on all corresponding destination regions that are either
-visible or are retained in backing store.
-If the destination is a window with a background other than
-<symbol>None</symbol>,
-corresponding regions
-of the destination are tiled with that background
-(with plane-mask of all ones and
-<symbol>GXcopy</symbol>
-function).
-Regardless of tiling or whether the destination is a window or a pixmap,
-if graphics-exposures is
-<symbol>True</symbol>,
-then
-<symbol>GraphicsExpose</symbol>
-events for all corresponding destination regions are generated.
-If graphics-exposures is
-<symbol>True</symbol>
-but no
-<symbol>GraphicsExpose</symbol>
-events are generated, a
-<symbol>NoExpose</symbol>
-event is generated.
-Note that by default graphics-exposures is
-<symbol>True</symbol>
-in new GCs.
-</para>
-<para>
-<!-- .LP -->
-This function uses these GC components: function, plane-mask,
-subwindow-mode, graphics-exposures, clip-x-origin,
-clip-y-origin, and clip-mask.
-</para>
-<para>
-<!-- .LP -->
-<function>XCopyArea</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadMatch</errorname>
-errors.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To copy a single bit plane of a given drawable, use
-<function>XCopyPlane</function>.
-<indexterm><primary>Plane</primary><secondary>copying</secondary></indexterm>
-<indexterm><primary>Copying</primary><secondary>planes</secondary></indexterm>
-<indexterm significance="preferred"><primary>XCopyPlane</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XCopyPlane</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawablesrc,<parameter> dest</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intsrc_x,<parameter> src_y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>intdest_x,<parameter> dest_y</parameter></paramdef>
- <paramdef>unsignedlong<parameter> plane</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest</emphasis>
- </term>
- <listitem>
- <para>
-Specify the source and destination rectangles to be combined.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src_x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src_y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates,
-which are relative to the origin of the source rectangle
-and specify its upper-left corner.
-<!-- .ds Wh , which are the dimensions of both the source and destination rectangles -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
-<!-- .ds Dx , which are relative to the origin of the destination rectangle \ -->
-and specify its upper-left corner
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Dx.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>plane</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the bit plane.
-You must set exactly one bit to 1.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCopyPlane</function>
-function uses a single bit plane of the specified source rectangle
-combined with the specified GC to modify the specified rectangle of dest.
-The drawables must have the same root but need not have the same depth.
-If the drawables do not have the same root, a
-<errorname>BadMatch</errorname>
-error results.
-If plane does not have exactly one bit set to 1 and the value of plane
-is not less than %2 sup n%, where <emphasis remap='I'>n</emphasis> is the depth of src, a
-<errorname>BadValue</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-Effectively,
-<function>XCopyPlane</function>
-forms a pixmap of the same depth as the rectangle of dest and with a
-size specified by the source region.
-It uses the foreground/background pixels in the GC (foreground
-everywhere the bit plane in src contains a bit set to 1,
-background everywhere the bit plane in src contains a bit set to 0)
-and the equivalent of a
-<systemitem>CopyArea</systemitem>
-protocol request is performed with all the same exposure semantics.
-This can also be thought of as using the specified region of the source
-bit plane as a stipple with a fill-style of
-<symbol>FillOpaqueStippled</symbol>
-for filling a rectangular area of the destination.
-</para>
-<para>
-<!-- .LP -->
-This function uses these GC components: function, plane-mask, foreground,
-background, subwindow-mode, graphics-exposures, clip-x-origin, clip-y-origin,
-and clip-mask.
-</para>
-<para>
-<!-- .LP -->
-<function>XCopyPlane</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-<errorname>BadMatch</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-</sect1>
-<sect1 id="Drawing_Points_Lines_Rectangles_and_Arcs">
-<title>Drawing Points, Lines, Rectangles, and Arcs</title>
-<!-- .XS -->
-<!-- (SN Drawing Points, Lines, Rectangles, and Arcs -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to draw:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-A single point or multiple points
- </para>
- </listitem>
- <listitem>
- <para>
-A single line or multiple lines
- </para>
- </listitem>
- <listitem>
- <para>
-A single rectangle or multiple rectangles
- </para>
- </listitem>
- <listitem>
- <para>
-A single arc or multiple arcs
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Some of the functions described in the following sections
-use these structures:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XSegment</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i -->
-<!-- .ta .5i -->
-typedef struct {
- short x1, y1, x2, y2;
-} XSegment;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>XPoint</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i -->
-<!-- .ta .5i -->
-typedef struct {
- short x, y;
-} XPoint;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>XRectangle</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i -->
-<!-- .ta .5i -->
-typedef struct {
- short x, y;
- unsigned short width, height;
-} XRectangle;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>XArc</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-typedef struct {
- short x, y;
- unsigned short width, height;
- short angle1, angle2; /* Degrees * 64 */
-} XArc;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-All x and y members are signed integers.
-The width and height members are 16-bit unsigned integers.
-You should be careful not to generate coordinates and sizes
-out of the 16-bit ranges, because the protocol only has 16-bit fields
-for these values.
-</para>
-<sect2 id="Drawing_Single_and_Multiple_Points">
-<title>Drawing Single and Multiple Points</title>
-<!-- .XS -->
-<!-- (SN Drawing Single and Multiple Points -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Points</primary><secondary>drawing</secondary></indexterm>
-<indexterm><primary>Drawing</primary><secondary>points</secondary></indexterm>
-<indexterm><primary>XDrawPoints</primary></indexterm>
-<indexterm><primary>XDrawPoint</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-To draw a single point in a given drawable, use
-<function>XDrawPoint</function>.
-<indexterm significance="preferred"><primary>XDrawPoint</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawPoint</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates where you want the point drawn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To draw multiple points in a given drawable, use
-<function>XDrawPoints</function>.
-<indexterm significance="preferred"><primary>XDrawPoints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawPoints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>XPoint<parameter> *points</parameter></paramdef>
- <paramdef>int<parameter> npoints</parameter></paramdef>
- <paramdef>int<parameter> mode</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>points</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of points.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>npoints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of points in the array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the coordinate mode.
-You can pass
-<symbol>CoordModeOrigin</symbol>
-or
-<symbol>CoordModePrevious</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDrawPoint</function>
-function uses the foreground pixel and function components of the
-GC to draw a single point into the specified drawable;
-<function>XDrawPoints</function>
-draws multiple points this way.
-<symbol>CoordModeOrigin</symbol>
-treats all coordinates as relative to the origin,
-and
-<symbol>CoordModePrevious</symbol>
-treats all coordinates after the first as relative to the previous point.
-<function>XDrawPoints</function>
-draws the points in the order listed in the array.
-</para>
-<para>
-<!-- .LP -->
-Both functions use these GC components: function, plane-mask,
-foreground, subwindow-mode, clip-x-origin, clip-y-origin, and clip-mask.
-</para>
-<para>
-<!-- .LP -->
-<function>XDrawPoint</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadMatch</errorname>
-errors.
-<function>XDrawPoints</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-<errorname>BadMatch</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Drawing_Single_and_Multiple_Lines">
-<title>Drawing Single and Multiple Lines</title>
-<!-- .XS -->
-<!-- (SN Drawing Single and Multiple Lines -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Lines</primary><secondary>drawing</secondary></indexterm>
-<indexterm><primary>Drawing</primary><secondary>lines</secondary></indexterm>
-<indexterm><primary>XDrawLine</primary></indexterm>
-<indexterm><primary>XDrawLines</primary></indexterm>
-<indexterm><primary>Polygons</primary><secondary>drawing</secondary></indexterm>
-<indexterm><primary>Drawing</primary><secondary>polygons</secondary></indexterm>
-<indexterm><primary>XDrawSegments</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-To draw a single line between two points in a given drawable, use
-<function>XDrawLine</function>.
-<indexterm significance="preferred"><primary>XDrawLine</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawLine</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx1,y1,x2,<parameter> y2</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x1</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y1</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x2</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y2</emphasis>
- </term>
- <listitem>
- <para>
-Specify the points (x1, y1) and (x2, y2) to be connected.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To draw multiple lines in a given drawable, use
-<function>XDrawLines</function>.
-<indexterm significance="preferred"><primary>XDrawLines</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawLines</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>XPoint<parameter> *points</parameter></paramdef>
- <paramdef>int<parameter> npoints</parameter></paramdef>
- <paramdef>int<parameter> mode</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>points</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of points.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>npoints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of points in the array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the coordinate mode.
-You can pass
-<symbol>CoordModeOrigin</symbol>
-or
-<symbol>CoordModePrevious</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To draw multiple, unconnected lines in a given drawable,
-use
-<function>XDrawSegments</function>.
-<indexterm significance="preferred"><primary>XDrawSegments</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawSegments</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>XSegment<parameter> *segments</parameter></paramdef>
- <paramdef>int<parameter> nsegments</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>segments</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of segments.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nsegments</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of segments in the array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDrawLine</function>
-function uses the components of the specified GC to
-draw a line between the specified set of points (x1, y1) and (x2, y2).
-It does not perform joining at coincident endpoints.
-For any given line,
-<function>XDrawLine</function>
-does not draw a pixel more than once.
-If lines intersect, the intersecting pixels are drawn multiple times.
-</para>
-<para>
-<!-- .LP -->
-The
-<function>XDrawLines</function>
-function uses the components of the specified GC to draw
-npoints-1 lines between each pair of points (point[i], point[i+1])
-in the array of
-<structname>XPoint</structname>
-structures.
-It draws the lines in the order listed in the array.
-The lines join correctly at all intermediate points, and if the first and last
-points coincide, the first and last lines also join correctly.
-For any given line,
-<function>XDrawLines</function>
-does not draw a pixel more than once.
-If thin (zero line-width) lines intersect,
-the intersecting pixels are drawn multiple times.
-If wide lines intersect, the intersecting pixels are drawn only once, as though
-the entire
-<systemitem>PolyLine</systemitem>
-protocol request were a single, filled shape.
-<symbol>CoordModeOrigin</symbol>
-treats all coordinates as relative to the origin,
-and
-<symbol>CoordModePrevious</symbol>
-treats all coordinates after the first as relative to the previous point.
-</para>
-<para>
-<!-- .LP -->
-The
-<function>XDrawSegments</function>
-function draws multiple, unconnected lines.
-For each segment,
-<function>XDrawSegments</function>
-draws a
-line between (x1, y1) and (x2, y2).
-It draws the lines in the order listed in the array of
-<structname>XSegment</structname>
-structures and does not perform joining at coincident endpoints.
-For any given line,
-<function>XDrawSegments</function>
-does not draw a pixel more than once.
-If lines intersect, the intersecting pixels are drawn multiple times.
-</para>
-<para>
-<!-- .LP -->
-All three functions use these GC components:
-function, plane-mask, line-width,
-line-style, cap-style, fill-style, subwindow-mode,
-clip-x-origin, clip-y-origin, and clip-mask.
-The
-<function>XDrawLines</function>
-function also uses the join-style GC component.
-All three functions also use these GC mode-dependent components:
-foreground, background, tile, stipple, tile-stipple-x-origin,
-tile-stipple-y-origin, dash-offset, and dash-list.
-</para>
-<para>
-<!-- .LP -->
-<function>XDrawLine</function>,
-<function>XDrawLines</function>,
-and
-<function>XDrawSegments</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadMatch</errorname>
-errors.
-<function>XDrawLines</function>
-also can generate
-<errorname>BadValue</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Drawing_Single_and_Multiple_Rectangles_">
-<title>Drawing Single and Multiple Rectangles </title>
-<!-- .XS -->
-<!-- (SN Drawing Single and Multiple Rectangles -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Rectangles</primary><secondary>drawing</secondary></indexterm>
-<indexterm><primary>Drawing</primary><secondary>rectangles</secondary></indexterm>
-<indexterm><primary>XDrawRectangle</primary></indexterm>
-<indexterm><primary>XDrawRectangles</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-To draw the outline of a single rectangle in a given drawable, use
-<function>XDrawRectangle</function>.
-<indexterm significance="preferred"><primary>XDrawRectangle</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawRectangle</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy , which specify the upper-left corner of the rectangle -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
-<!-- .ds Wh , which specify the dimensions of the rectangle -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To draw the outline of multiple rectangles
-in a given drawable, use
-<function>XDrawRectangles</function>.
-<indexterm significance="preferred"><primary>XDrawRectangles</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawRectangles</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>XRectangle<parameter> rectangles[]</parameter></paramdef>
- <paramdef>int<parameter> nrectangles</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>rectangles</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of rectangles.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nrectangles</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of rectangles in the array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDrawRectangle</function>
-and
-<function>XDrawRectangles</function>
-functions draw the outlines of the specified rectangle or rectangles as
-if a five-point
-<systemitem>PolyLine</systemitem>
-protocol request were specified for each rectangle:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-[x,y] [x+width,y] [x+width,y+height] [x,y+height] [x,y]
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-For the specified rectangle or rectangles,
-these functions do not draw a pixel more than once.
-<function>XDrawRectangles</function>
-draws the rectangles in the order listed in the array.
-If rectangles intersect,
-the intersecting pixels are drawn multiple times.
-</para>
-<para>
-<!-- .LP -->
-Both functions use these GC components:
-function, plane-mask, line-width,
-line-style, cap-style, join-style, fill-style,
-subwindow-mode, clip-x-origin, clip-y-origin, and clip-mask.
-They also use these GC mode-dependent components:
-foreground, background, tile, stipple, tile-stipple-x-origin,
-tile-stipple-y-origin, dash-offset, and dash-list.
-</para>
-<para>
-<!-- .LP -->
-<function>XDrawRectangle</function>
-and
-<function>XDrawRectangles</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadMatch</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Drawing_Single_and_Multiple_Arcs">
-<title>Drawing Single and Multiple Arcs</title>
-<!-- .XS -->
-<!-- (SN Drawing Single and Multiple Arcs -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Drawing</primary><secondary>arcs</secondary></indexterm>
-<indexterm><primary>XDrawArc</primary></indexterm>
-<indexterm><primary>Arcs</primary><secondary>drawing</secondary></indexterm>
-<indexterm><primary>XDrawArcs</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To draw a single arc in a given drawable, use
-<function>XDrawArc</function>.
-<indexterm significance="preferred"><primary>XDrawArc</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawArc</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>intangle1,<parameter> angle2</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy , which are relative to the origin of the drawable \ -->
-and specify the upper-left corner of the bounding rectangle
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
-<!-- .ds Wh , which are the major and minor axes of the arc -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>angle1</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the start of the arc relative to the three-o'clock position
-from the center, in units of degrees * 64.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>angle2</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the path and extent of the arc relative to the start of the
-arc, in units of degrees * 64.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To draw multiple arcs in a given drawable, use
-<function>XDrawArcs</function>.
-<indexterm significance="preferred"><primary>XDrawArcs</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawArcs</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>XArc<parameter> *arcs</parameter></paramdef>
- <paramdef>int<parameter> narcs</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>arcs</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of arcs.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>narcs</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of arcs in the array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .EQ -->
-delim %%
-<!-- .EN -->
-<function>XDrawArc</function>
-draws a single circular or elliptical arc, and
-<function>XDrawArcs</function>
-draws multiple circular or elliptical arcs.
-Each arc is specified by a rectangle and two angles.
-The center of the circle or ellipse is the center of the
-rectangle, and the major and minor axes are specified by the width and height.
-Positive angles indicate counterclockwise motion,
-and negative angles indicate clockwise motion.
-If the magnitude of angle2 is greater than 360 degrees,
-<function>XDrawArc</function>
-or
-<function>XDrawArcs</function>
-truncates it to 360 degrees.
-</para>
-<para>
-<!-- .LP -->
-For an arc specified as %[ ~x, ~y, ~width , ~height, ~angle1, ~angle2 ]%,
-the origin of the major and minor axes is at
-% [ x +^ {width over 2} , ~y +^ {height over 2} ]%,
-and the infinitely thin path describing the entire circle or ellipse
-intersects the horizontal axis at % [ x, ~y +^ {height over 2} ]% and
-% [ x +^ width , ~y +^ { height over 2 }] %
-and intersects the vertical axis at % [ x +^ { width over 2 } , ~y ]% and
-% [ x +^ { width over 2 }, ~y +^ height ]%.
-These coordinates can be fractional
-and so are not truncated to discrete coordinates.
-The path should be defined by the ideal mathematical path.
-For a wide line with line-width lw,
-the bounding outlines for filling are given
-by the two infinitely thin paths consisting of all points whose perpendicular
-distance from the path of the circle/ellipse is equal to lw/2
-(which may be a fractional value).
-The cap-style and join-style are applied the same as for a line
-corresponding to the tangent of the circle/ellipse at the endpoint.
-</para>
-<para>
-<!-- .LP -->
-For an arc specified as % [ ~x, ~y, ~width, ~height, ~angle1, ~angle2 ]%,
-the angles must be specified
-in the effectively skewed coordinate system of the ellipse (for a
-circle, the angles and coordinate systems are identical). The
-relationship between these angles and angles expressed in the normal
-coordinate system of the screen (as measured with a protractor) is as
-follows:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-% roman "skewed-angle" ~ = ~ atan left ( tan ( roman "normal-angle" )
- * width over height right ) +^ adjust%
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The skewed-angle and normal-angle are expressed in radians (rather
-than in degrees scaled by 64) in the range % [ 0 , ~2 pi ]% and where atan
-returns a value in the range % [ - pi over 2 , ~pi over 2 ] %
-and adjust is:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA 1i 2i -->
-<!-- .ta 1i 2i -->
-%0% for normal-angle in the range % [ 0 , ~pi over 2 ]%
-%pi% for normal-angle in the range % [ pi over 2 , ~{3 pi} over 2 ]%
-%2 pi% for normal-angle in the range % [ {3 pi} over 2 , ~2 pi ]%
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-For any given arc,
-<function>XDrawArc</function>
-and
-<function>XDrawArcs</function>
-do not draw a pixel more than once.
-If two arcs join correctly and if the line-width is greater than zero
-and the arcs intersect,
-<function>XDrawArc</function>
-and
-<function>XDrawArcs</function>
-do not draw a pixel more than once.
-Otherwise,
-the intersecting pixels of intersecting arcs are drawn multiple times.
-Specifying an arc with one endpoint and a clockwise extent draws the same pixels
-as specifying the other endpoint and an equivalent counterclockwise extent,
-except as it affects joins.
-</para>
-<para>
-<!-- .LP -->
-If the last point in one arc coincides with the first point in the following
-arc, the two arcs will join correctly.
-If the first point in the first arc coincides with the last point in the last
-arc, the two arcs will join correctly.
-By specifying one axis to be zero, a horizontal or vertical line can be
-drawn.
-Angles are computed based solely on the coordinate system and ignore the
-aspect ratio.
-</para>
-<para>
-<!-- .LP -->
-Both functions use these GC components:
-function, plane-mask, line-width, line-style, cap-style, join-style,
-fill-style, subwindow-mode, clip-x-origin, clip-y-origin, and clip-mask.
-They also use these GC mode-dependent components:
-foreground, background, tile, stipple, tile-stipple-x-origin,
-tile-stipple-y-origin, dash-offset, and dash-list.
-</para>
-<para>
-<!-- .LP -->
-<function>XDrawArc</function>
-and
-<function>XDrawArcs</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadMatch</errorname>
-errors.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Filling_Areas">
-<title>Filling Areas</title>
-<!-- .XS -->
-<!-- (SN Filling Areas -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to fill:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-A single rectangle or multiple rectangles
- </para>
- </listitem>
- <listitem>
- <para>
-A single polygon
- </para>
- </listitem>
- <listitem>
- <para>
-A single arc or multiple arcs
- </para>
- </listitem>
-</itemizedlist>
-<sect2 id="Filling_Single_and_Multiple_Rectangles">
-<title>Filling Single and Multiple Rectangles</title>
-<!-- .XS -->
-<!-- (SN Filling Single and Multiple Rectangles -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Filling</primary><secondary>rectangles</secondary></indexterm>
-<indexterm><primary>XFillRectangle</primary></indexterm>
-<indexterm><primary>Rectangle</primary><secondary>filling</secondary></indexterm>
-<indexterm><primary>XFillRectangles</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To fill a single rectangular area in a given drawable, use
-<function>XFillRectangle</function>.
-<indexterm significance="preferred"><primary>XFillRectangle</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFillRectangle</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy , which are relative to the origin of the drawable \ -->
-and specify the upper-left corner of the rectangle
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
-<!-- .ds Wh , which are the dimensions of the rectangle to be filled -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To fill multiple rectangular areas in a given drawable, use
-<function>XFillRectangles</function>.
-<indexterm significance="preferred"><primary>XFillRectangles</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFillRectangles</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>XRectangle<parameter> *rectangles</parameter></paramdef>
- <paramdef>int<parameter> nrectangles</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>rectangles</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of rectangles.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nrectangles</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of rectangles in the array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFillRectangle</function>
-and
-<function>XFillRectangles</function>
-functions fill the specified rectangle or rectangles
-as if a four-point
-<systemitem>FillPolygon</systemitem>
-protocol request were specified for each rectangle:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-[x,y] [x+width,y] [x+width,y+height] [x,y+height]
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-Each function uses the x and y coordinates,
-width and height dimensions, and GC you specify.
-</para>
-<para>
-<!-- .LP -->
-<function>XFillRectangles</function>
-fills the rectangles in the order listed in the array.
-For any given rectangle,
-<function>XFillRectangle</function>
-and
-<function>XFillRectangles</function>
-do not draw a pixel more than once.
-If rectangles intersect, the intersecting pixels are
-drawn multiple times.
-</para>
-<para>
-<!-- .LP -->
-Both functions use these GC components:
-function, plane-mask, fill-style, subwindow-mode,
-clip-x-origin, clip-y-origin, and clip-mask.
-They also use these GC mode-dependent components:
-foreground, background, tile, stipple, tile-stipple-x-origin,
-and tile-stipple-y-origin.
-</para>
-<para>
-<!-- .LP -->
-<function>XFillRectangle</function>
-and
-<function>XFillRectangles</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadMatch</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Filling_a_Single_Polygon">
-<title>Filling a Single Polygon</title>
-<!-- .XS -->
-<!-- (SN Filling a Single Polygon -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To fill a polygon area in a given drawable, use
-<function>XFillPolygon</function>.
-<indexterm><primary>Polygons</primary><secondary>filling</secondary></indexterm>
-<indexterm><primary>Filling</primary><secondary>polygon</secondary></indexterm>
-<indexterm significance="preferred"><primary>XFillPolygon</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFillPolygon</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>XPoint<parameter> *points</parameter></paramdef>
- <paramdef>int<parameter> npoints</parameter></paramdef>
- <paramdef>int<parameter> shape</parameter></paramdef>
- <paramdef>int<parameter> mode</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>points</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of points.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>npoints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of points in the array.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>shape</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a shape that helps the server to improve performance.
-You can pass
-<symbol>Complex</symbol>,
-<symbol>Convex</symbol>,
-or
-<symbol>Nonconvex</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the coordinate mode.
-You can pass
-<symbol>CoordModeOrigin</symbol>
-or
-<symbol>CoordModePrevious</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XFillPolygon</function>
-fills the region closed by the specified path.
-The path is closed
-automatically if the last point in the list does not coincide with the
-first point.
-<function>XFillPolygon</function>
-does not draw a pixel of the region more than once.
-<symbol>CoordModeOrigin</symbol>
-treats all coordinates as relative to the origin,
-and
-<symbol>CoordModePrevious</symbol>
-treats all coordinates after the first as relative to the previous point.
-</para>
-<para>
-<!-- .LP -->
-Depending on the specified shape, the following occurs:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-If shape is
-<symbol>Complex</symbol>,
-the path may self-intersect.
-Note that contiguous coincident points in the path are not treated
-as self-intersection.
- </para>
- </listitem>
- <listitem>
- <para>
-If shape is
-<symbol>Convex</symbol>,
-for every pair of points inside the polygon,
-the line segment connecting them does not intersect the path.
-If known by the client,
-specifying
-<symbol>Convex</symbol>
-can improve performance.
-If you specify
-<symbol>Convex</symbol>
-for a path that is not convex,
-the graphics results are undefined.
- </para>
- </listitem>
- <listitem>
- <para>
-If shape is
-<symbol>Nonconvex</symbol>,
-the path does not self-intersect, but the shape is not
-wholly convex.
-If known by the client,
-specifying
-<symbol>Nonconvex</symbol>
-instead of
-<symbol>Complex</symbol>
-may improve performance.
-If you specify
-<symbol>Nonconvex</symbol>
-for a self-intersecting path, the graphics results are undefined.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The fill-rule of the GC controls the filling behavior of
-self-intersecting polygons.
-</para>
-<para>
-<!-- .LP -->
-This function uses these GC components:
-function, plane-mask, fill-style, fill-rule, subwindow-mode, clip-x-origin,
-clip-y-origin, and clip-mask.
-It also uses these GC mode-dependent components:
-foreground, background, tile, stipple, tile-stipple-x-origin,
-and tile-stipple-y-origin.
-</para>
-<para>
-<!-- .LP -->
-<function>XFillPolygon</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-<errorname>BadMatch</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Filling_Single_and_Multiple_Arcs">
-<title>Filling Single and Multiple Arcs</title>
-<!-- .XS -->
-<!-- (SN Filling Single and Multiple Arcs -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>XFillArc</primary></indexterm>
-<indexterm><primary>Arcs</primary><secondary>filling</secondary></indexterm>
-<indexterm><primary>Filling</primary><secondary>arcs</secondary></indexterm>
-To fill a single arc in a given drawable, use
-<function>XFillArc</function>.
-<indexterm significance="preferred"><primary>XFillArc</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFillArc</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>intangle1,<parameter> angle2</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy , which are relative to the origin of the drawable \ -->
-and specify the upper-left corner of the bounding rectangle
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
-<!-- .ds Wh , which are the major and minor axes of the arc -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>angle1</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the start of the arc relative to the three-o'clock position
-from the center, in units of degrees * 64.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>angle2</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the path and extent of the arc relative to the start of the
-arc, in units of degrees * 64.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To fill multiple arcs in a given drawable, use
-<function>XFillArcs</function>.
-<indexterm significance="preferred"><primary>XFillArcs</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFillArcs</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>XArc<parameter> *arcs</parameter></paramdef>
- <paramdef>int<parameter> narcs</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>arcs</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of arcs.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>narcs</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of arcs in the array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-For each arc,
-<function>XFillArc</function>
-or
-<function>XFillArcs</function>
-fills the region closed by the infinitely thin path
-described by the specified arc and, depending on the
-arc-mode specified in the GC, one or two line segments.
-For
-<symbol>ArcChord</symbol>,
-the single line segment joining the endpoints of the arc is used.
-For
-<symbol>ArcPieSlice</symbol>,
-the two line segments joining the endpoints of the arc with the center
-point are used.
-<function>XFillArcs</function>
-fills the arcs in the order listed in the array.
-For any given arc,
-<function>XFillArc</function>
-and
-<function>XFillArcs</function>
-do not draw a pixel more than once.
-If regions intersect,
-the intersecting pixels are drawn multiple times.
-</para>
-<para>
-<!-- .LP -->
-Both functions use these GC components:
-function, plane-mask, fill-style, arc-mode, subwindow-mode, clip-x-origin,
-clip-y-origin, and clip-mask.
-They also use these GC mode-dependent components:
-foreground, background, tile, stipple, tile-stipple-x-origin,
-and tile-stipple-y-origin.
-</para>
-<para>
-<!-- .LP -->
-<function>XFillArc</function>
-and
-<function>XFillArcs</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadMatch</errorname>
-errors.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Font_Metrics">
-<title>Font Metrics</title>
-<!-- .XS -->
-<!-- (SN Font Metrics -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Font</primary></indexterm>
-A font is a graphical description of a set of characters that are used to
-increase efficiency whenever a set of small, similar sized patterns are
-repeatedly used.
-</para>
-<para>
-<!-- .LP -->
-This section discusses how to:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Load and free fonts
- </para>
- </listitem>
- <listitem>
- <para>
-Obtain and free font names
- </para>
- </listitem>
- <listitem>
- <para>
-Compute character string sizes
- </para>
- </listitem>
- <listitem>
- <para>
-Compute logical extents
- </para>
- </listitem>
- <listitem>
- <para>
-Query character string sizes
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The X server loads fonts whenever a program requests a new font.
-The server can cache fonts for quick lookup.
-Fonts are global across all screens in a server.
-Several levels are possible when dealing with fonts.
-Most applications simply use
-<function>XLoadQueryFont</function>
-to load a font and query the font metrics.
-</para>
-<para>
-<!-- .LP -->
-Characters in fonts are regarded as masks.
-Except for image text requests,
-the only pixels modified are those in which bits are set to 1 in the character.
-This means that it makes sense to draw text using stipples or tiles
-(for example, many menus gray-out unusable entries).
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-The
-<structname>XFontStruct</structname>
-structure contains all of the information for the font
-and consists of the font-specific information as well as
-a pointer to an array of
-<structname>XCharStruct</structname>
-structures for the
-characters contained in the font.
-The
-<structname>XFontStruct</structname>,
-<structname>XFontProp</structname>,
-and
-<structname>XCharStruct</structname>
-structures contain:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XCharStruct</primary></indexterm>
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-typedef struct {
- short lbearing; /* origin to left edge of raster */
- short rbearing; /* origin to right edge of raster */
- short width; /* advance to next char's origin */
- short ascent; /* baseline to top edge of raster */
- short descent; /* baseline to bottom edge of raster */
- unsigned short attributes; /* per char flags (not predefined) */
-} XCharStruct;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XFontProp</primary></indexterm>
-<literallayout class="monospaced">
-<!-- .TA .5i 1i 3i -->
-<!-- .ta .5i 1i 3i -->
-typedef struct {
- Atom name;
- unsigned long card32;
-} XFontProp;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XChar2b</primary></indexterm>
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-typedef struct { /* normal 16 bit characters are two bytes */
- unsigned char byte1;
- unsigned char byte2;
-} XChar2b;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XFontStruct</primary></indexterm>
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-typedef struct {
- XExtData *ext_data; /* hook for extension to hang data */
- Font fid; /* Font id for this font */
- unsigned direction; /* hint about the direction font is painted */
- unsigned min_char_or_byte2; /* first character */
- unsigned max_char_or_byte2; /* last character */
- unsigned min_byte1; /* first row that exists */
- unsigned max_byte1; /* last row that exists */
- Bool all_chars_exist; /* flag if all characters have nonzero size */
- unsigned default_char; /* char to print for undefined character */
- int n_properties; /* how many properties there are */
- XFontProp *properties; /* pointer to array of additional properties */
- XCharStruct min_bounds; /* minimum bounds over all existing char */
- XCharStruct max_bounds; /* maximum bounds over all existing char */
- XCharStruct *per_char; /* first_char to last_char information */
- int ascent; /* logical extent above baseline for spacing */
- int descent; /* logical descent below baseline for spacing */
-} XFontStruct;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-X supports single byte/character, two bytes/character matrix,
-and 16-bit character text operations.
-Note that any of these forms can be used with a font, but a
-single byte/character text request can only specify a single byte
-(that is, the first row of a 2-byte font).
-You should view 2-byte fonts as a two-dimensional matrix of defined
-characters: byte1 specifies the range of defined rows and
-byte2 defines the range of defined columns of the font.
-Single byte/character fonts have one row defined, and the byte2 range
-specified in the structure defines a range of characters.
-</para>
-<para>
-<!-- .LP -->
-The bounding box of a character is defined by the
-<structname>XCharStruct</structname>
-of that character.
-When characters are absent from a font,
-the default_char is used.
-When fonts have all characters of the same size,
-only the information in the
-<structname>XFontStruct</structname>
-min and max bounds are used.
-</para>
-<para>
-<!-- .LP -->
-The members of the
-<structname>XFontStruct</structname>
-have the following semantics:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The direction member can be either
-<symbol>FontLeftToRight</symbol>
-or
-<symbol>FontRightToLeft</symbol>.
-It is just a hint as to whether most
-<structname>XCharStruct</structname>
-elements
-have a positive
-(<symbol>FontLeftToRight</symbol>)
-or a negative
-(<symbol>FontRightToLeft</symbol>)
-character width
-metric.
-The core protocol defines no support for vertical text.
- </para>
- </listitem>
- <listitem>
- <para>
-If the min_byte1 and max_byte1 members are both zero, min_char_or_byte2
-specifies the linear character index corresponding to the first element
-of the per_char array, and max_char_or_byte2 specifies the linear character
-index of the last element.
- </para>
- </listitem>
- <listitem>
- <para>
-If either min_byte1 or max_byte1 are nonzero, both
-min_char_or_byte2 and max_char_or_byte2 are less than 256,
-and the 2-byte character index values corresponding to the
-per_char array element N (counting from 0) are:
- </para>
- </listitem>
- <listitem>
- <para>
-<!-- .nf -->
- byte1 = N/D + min_byte1
-<!-- .br -->
- byte2 = N\\D + min_char_or_byte2
- </para>
- </listitem>
- <listitem>
- <para>
-<!-- .fi -->
-where:
- </para>
- </listitem>
- <listitem>
- <para>
-<!-- .nf -->
- D = max_char_or_byte2 - min_char_or_byte2 + 1
- / = integer division
- \\ = integer modulus
-<!-- .fi -->
- </para>
- </listitem>
- <listitem>
- <para>
-If the per_char pointer is NULL,
-all glyphs between the first and last character indexes
-inclusive have the same information,
-as given by both min_bounds and max_bounds.
- </para>
- </listitem>
- <listitem>
- <para>
-If all_chars_exist is
-<symbol>True</symbol>,
-all characters in the per_char array have nonzero bounding boxes.
- </para>
- </listitem>
- <listitem>
- <para>
-The default_char member specifies the character that will be used when an
-undefined or nonexistent character is printed.
-The default_char is a 16-bit character (not a 2-byte character).
-For a font using 2-byte matrix format,
-the default_char has byte1 in the most-significant byte
-and byte2 in the least significant byte.
-If the default_char itself specifies an undefined or nonexistent character,
-no printing is performed for an undefined or nonexistent character.
- </para>
- </listitem>
- <listitem>
- <para>
-The min_bounds and max_bounds members contain the most extreme values of
-each individual
-<structname>XCharStruct</structname>
-component over all elements of this array
-(and ignore nonexistent characters).
-The bounding box of the font (the smallest
-rectangle enclosing the shape obtained by superimposing all of the
-characters at the same origin [x,y]) has its upper-left coordinate at:
-<literallayout class="monospaced">
- [x + min_bounds.lbearing, y - max_bounds.ascent]
-</literallayout>
- </para>
- </listitem>
- <listitem>
- <para>
-Its width is:
-<literallayout class="monospaced">
- max_bounds.rbearing - min_bounds.lbearing
-</literallayout>
- </para>
- </listitem>
- <listitem>
- <para>
-Its height is:
-<literallayout class="monospaced">
- max_bounds.ascent + max_bounds.descent
-</literallayout>
- </para>
- </listitem>
- <listitem>
- <para>
-The ascent member is the logical extent of the font above the baseline that is
-used for determining line spacing.
-Specific characters may extend beyond
-this.
- </para>
- </listitem>
- <listitem>
- <para>
-The descent member is the logical extent of the font at or below the
-baseline that is used for determining line spacing.
-Specific characters may extend beyond this.
- </para>
- </listitem>
- <listitem>
- <para>
-If the baseline is at Y-coordinate y,
-the logical extent of the font is inclusive between the Y-coordinate
-values (y - font.ascent) and (y + font.descent - 1).
-Typically,
-the minimum interline spacing between rows of text is given
-by ascent + descent.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-For a character origin at [x,y],
-the bounding box of a character (that is,
-the smallest rectangle that encloses the character's shape)
-described in terms of
-<structname>XCharStruct</structname>
-components is a rectangle with its upper-left corner at:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-[x + lbearing, y - ascent]
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-Its width is:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-rbearing - lbearing
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-Its height is:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-ascent + descent
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The origin for the next character is defined to be:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-[x + width, y]
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The lbearing member defines the extent of the left edge of the character ink
-from the origin.
-The rbearing member defines the extent of the right edge of the character ink
-from the origin.
-The ascent member defines the extent of the top edge of the character ink
-from the origin.
-The descent member defines the extent of the bottom edge of the character ink
-from the origin.
-The width member defines the logical width of the character.
-</para>
-<para>
-<!-- .LP -->
-Note that the baseline (the y position of the character origin)
-is logically viewed as being the scanline just below nondescending characters.
-When descent is zero,
-only pixels with Y-coordinates less than y are drawn,
-and the origin is logically viewed as being coincident with the left edge of
-a nonkerned character.
-When lbearing is zero,
-no pixels with X-coordinate less than x are drawn.
-Any of the
-<structname>XCharStruct</structname>
-metric members could be negative.
-If the width is negative,
-the next character will be placed to the left of the current origin.
-</para>
-<para>
-<!-- .LP -->
-The X protocol does not define the interpretation of the attributes member
-in the
-<structname>XCharStruct</structname>
-structure.
-A nonexistent character is represented with all members of its
-<structname>XCharStruct</structname>
-set to zero.
-</para>
-<para>
-<!-- .LP -->
-A font is not guaranteed to have any properties.
-The interpretation of the property value (for example, long or unsigned long)
-must be derived from <emphasis remap='I'>a priori</emphasis> knowledge of the property.
-A basic set of font properties is specified in the X Consortium standard
-<emphasis remap='I'>X Logical Font Description Conventions</emphasis>.
-</para>
-<sect2 id="Loading_and_Freeing_Fonts">
-<title>Loading and Freeing Fonts</title>
-<!-- .XS -->
-<!-- (SN Loading and Freeing Fonts -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to load fonts, get font information,
-unload fonts, and free font information.
-<indexterm><primary>Fonts</primary><secondary>getting information</secondary></indexterm>
-<indexterm><primary>Fonts</primary><secondary>unloading</secondary></indexterm>
-<indexterm><primary>Fonts</primary><secondary>freeing font information</secondary></indexterm>
-A few font functions use a
-<type>GContext</type>
-resource ID or a font ID interchangeably.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To load a given font, use
-<function>XLoadFont</function>.
-<indexterm significance="preferred"><primary>XLoadFont</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Font <function>XLoadFont</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *name</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the name of the font,
-which is a null-terminated string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XLoadFont</function>
-function loads the specified font and returns its associated font ID.
-If the font name is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-Use of uppercase or lowercase does not matter.
-When the characters ``?'' and ``*'' are used in a font name, a
-pattern match is performed and any matching font is used.
-In the pattern,
-the ``?'' character will match any single character,
-and the ``*'' character will match any number of characters.
-A structured format for font names is specified in the X Consortium standard
-<emphasis remap='I'>X Logical Font Description Conventions</emphasis>.
-If
-<function>XLoadFont</function>
-was unsuccessful at loading the specified font,
-a
-<errorname>BadName</errorname>
-error results.
-Fonts are not associated with a particular screen
-and can be stored as a component
-of any GC.
-When the font is no longer needed, call
-<function>XUnloadFont</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XLoadFont</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadName</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To return information about an available font, use
-<function>XQueryFont</function>.
-<indexterm significance="preferred"><primary>XQueryFont</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XFontStruct *<function>XQueryFont</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XID<parameter> font_ID</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_ID</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font ID or the
-<type>GContext</type>
-ID.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XQueryFont</function>
-function returns a pointer to the
-<structname>XFontStruct</structname>
-structure, which contains information associated with the font.
-You can query a font or the font stored in a GC.
-The font ID stored in the
-<structname>XFontStruct</structname>
-structure will be the
-<type>GContext</type>
-ID, and you need to be careful when using this ID in other functions
-(see
-<function>XGContextFromGC</function>).
-If the font does not exist,
-<function>XQueryFont</function>
-returns NULL.
-To free this data, use
-<function>XFreeFontInfo</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To perform a
-<function>XLoadFont</function>
-and
-<function>XQueryFont</function>
-in a single operation, use
-<function>XLoadQueryFont</function>.
-<indexterm significance="preferred"><primary>XLoadQueryFont</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XFontStruct *<function>XLoadQueryFont</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *name</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the name of the font,
-which is a null-terminated string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XLoadQueryFont</function>
-function provides the most common way for accessing a font.
-<function>XLoadQueryFont</function>
-both opens (loads) the specified font and returns a pointer to the
-appropriate
-<structname>XFontStruct</structname>
-structure.
-If the font name is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-If the font does not exist,
-<function>XLoadQueryFont</function>
-returns NULL.
-</para>
-<para>
-<!-- .LP -->
-<function>XLoadQueryFont</function>
-can generate a
-<errorname>BadAlloc</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To unload the font and free the storage used by the font structure
-that was allocated by
-<function>XQueryFont</function>
-or
-<function>XLoadQueryFont</function>,
-use
-<function>XFreeFont</function>.
-<indexterm significance="preferred"><primary>XFreeFont</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFreeFont</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XFontStruct<parameter> *font_struct</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_struct</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the storage associated with the font.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreeFont</function>
-function deletes the association between the font resource ID and the specified
-font and frees the
-<structname>XFontStruct</structname>
-structure.
-The font itself will be freed when no other resource references it.
-The data and the font should not be referenced again.
-</para>
-<para>
-<!-- .LP -->
-<function>XFreeFont</function>
-can generate a
-<errorname>BadFont</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To return a given font property, use
-<function>XGetFontProperty</function>.
-<indexterm significance="preferred"><primary>XGetFontProperty</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XGetFontProperty</function></funcdef>
- <paramdef>XFontStruct<parameter> *font_struct</parameter></paramdef>
- <paramdef>Atom<parameter> atom</parameter></paramdef>
- <paramdef>unsignedlong<parameter> *value_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_struct</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the storage associated with the font.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>atom</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the atom for the property name you want returned.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the value of the font property.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Given the atom for that property,
-the
-<function>XGetFontProperty</function>
-function returns the value of the specified font property.
-<function>XGetFontProperty</function>
-also returns
-<symbol>False</symbol>
-if the property was not defined or
-<symbol>True</symbol>
-if it was defined.
-A set of predefined atoms exists for font properties,
-which can be found in
-<filename class="headerfile">&lt;X11/Xatom.h&gt;</filename>.
-<indexterm type="file"><primary><filename class="headerfile">X11/Xatom.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xatom.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xatom.h&gt;</filename></secondary></indexterm>
-This set contains the standard properties associated with
-a font.
-Although it is not guaranteed,
-it is likely that the predefined font properties will be present.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To unload a font that was loaded by
-<function>XLoadFont</function>,
-use
-<function>XUnloadFont</function>.
-<indexterm significance="preferred"><primary>XUnloadFont</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XUnloadFont</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Font<parameter> font</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUnloadFont</function>
-function deletes the association between the font resource ID and the specified font.
-The font itself will be freed when no other resource references it.
-The font should not be referenced again.
-</para>
-<para>
-<!-- .LP -->
-<function>XUnloadFont</function>
-can generate a
-<errorname>BadFont</errorname>
-error.
-</para>
-</sect2>
-<sect2 id="Obtaining_and_Freeing_Font_Names_and_Information">
-<title>Obtaining and Freeing Font Names and Information</title>
-<!-- .XS -->
-<!-- (SN Obtaining and Freeing Font Names and Information -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-You obtain font names and information by matching a wildcard specification
-when querying a font type for a list of available sizes and so on.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To return a list of the available font names, use
-<function>XListFonts</function>.
-<indexterm significance="preferred"><primary>XListFonts</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char **<function>XListFonts</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *pattern</parameter></paramdef>
- <paramdef>int<parameter> maxnames</parameter></paramdef>
- <paramdef>int<parameter> *actual_count_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pattern</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the null-terminated pattern string that can contain wildcard
-characters.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>maxnames</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the maximum number of names to be returned.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>actual_count_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the actual number of font names.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XListFonts</function>
-function returns an array of available font names
-(as controlled by the font search path; see
-<function>XSetFontPath</function>)
-that match the string you passed to the pattern argument.
-The pattern string can contain any characters,
-but each asterisk (*) is a wildcard for any number of characters,
-and each question mark (?) is a wildcard for a single character.
-If the pattern string is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-Use of uppercase or lowercase does not matter.
-Each returned string is null-terminated.
-If the data returned by the server is in the Latin Portable Character Encoding,
-then the returned strings are in the Host Portable Character Encoding.
-Otherwise, the result is implementation-dependent.
-If there are no matching font names,
-<function>XListFonts</function>
-returns NULL.
-The client should call
-<function>XFreeFontNames</function>
-when finished with the result to free the memory.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To free a font name array, use
-<function>XFreeFontNames</function>.
-<indexterm significance="preferred"><primary>XFreeFontNames</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFreeFontNames</function></funcdef>
- <paramdef>char<parameter> *list[]</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the array of strings you want to free.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreeFontNames</function>
-function frees the array and strings returned by
-<function>XListFonts</function>
-or
-<function>XListFontsWithInfo</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the names and information about available fonts, use
-<function>XListFontsWithInfo</function>.
-<indexterm significance="preferred"><primary>XListFontsWithInfo</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char **<function>XListFontsWithInfo</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *pattern</parameter></paramdef>
- <paramdef>int<parameter> maxnames</parameter></paramdef>
- <paramdef>int<parameter> *count_return</parameter></paramdef>
- <paramdef>XFontStruct<parameter> **info_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pattern</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the null-terminated pattern string that can contain wildcard
-characters.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>maxnames</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the maximum number of names to be returned.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the actual number of matched font names.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>info_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the font information.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XListFontsWithInfo</function>
-function returns a list of font names that match the specified pattern and their
-associated font information.
-The list of names is limited to size specified by maxnames.
-The information returned for each font is identical to what
-<function>XLoadQueryFont</function>
-would return except that the per-character metrics are not returned.
-The pattern string can contain any characters,
-but each asterisk (*) is a wildcard for any number of characters,
-and each question mark (?) is a wildcard for a single character.
-If the pattern string is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-Use of uppercase or lowercase does not matter.
-Each returned string is null-terminated.
-If the data returned by the server is in the Latin Portable Character Encoding,
-then the returned strings are in the Host Portable Character Encoding.
-Otherwise, the result is implementation-dependent.
-If there are no matching font names,
-<function>XListFontsWithInfo</function>
-returns NULL.
-</para>
-<para>
-<!-- .LP -->
-To free only the allocated name array,
-the client should call
-<function>XFreeFontNames</function>.
-To free both the name array and the font information array
-or to free just the font information array,
-the client should call
-<function>XFreeFontInfo</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To free font structures and font names, use
-<function>XFreeFontInfo</function>.
-<indexterm significance="preferred"><primary>XFreeFontInfo</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFreeFontInfo</function></funcdef>
- <paramdef>char<parameter> **names</parameter></paramdef>
- <paramdef>XFontStruct<parameter> *free_info</parameter></paramdef>
- <paramdef>int<parameter> actual_count</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>names</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the list of font names.
-
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>free_info</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font information.
-
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>actual_count</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the actual number of font names.
-
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreeFontInfo</function>
-function frees a font structure or an array of font structures
-and optionally an array of font names.
-If NULL is passed for names, no font names are freed.
-If a font structure for an open font (returned by
-<function>XLoadQueryFont</function>)
-is passed, the structure is freed,
-but the font is not closed; use
-<function>XUnloadFont</function>
-to close the font.
-</para>
-</sect2>
-<sect2 id="Computing_Character_String_Sizes">
-<title>Computing Character String Sizes</title>
-<!-- .XS -->
-<!-- (SN Computing Character String Sizes -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to compute the width,
-the logical extents,
-and the server information about 8-bit and 2-byte text strings.
-<indexterm><primary>XTextWidth</primary></indexterm>
-<indexterm><primary>XTextWidth16</primary></indexterm>
-The width is computed by adding the character widths of all the characters.
-It does not matter if the font is an 8-bit or 2-byte font.
-These functions return the sum of the character metrics in pixels.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To determine the width of an 8-bit character string, use
-<function>XTextWidth</function>.
-<indexterm significance="preferred"><primary>XTextWidth</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XTextWidth</function></funcdef>
- <paramdef>XFontStruct<parameter> *font_struct</parameter></paramdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> count</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_struct</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font used for the width computation.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character count in the specified string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To determine the width of a 2-byte character string, use
-<function>XTextWidth16</function>.
-<indexterm significance="preferred"><primary>XTextWidth16</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XTextWidth16</function></funcdef>
- <paramdef>XFontStruct<parameter> *font_struct</parameter></paramdef>
- <paramdef>XChar2b<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> count</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_struct</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font used for the width computation.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character count in the specified string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-</para>
-</sect2>
-<sect2 id="Computing_Logical_Extents">
-<title>Computing Logical Extents</title>
-<!-- .XS -->
-<!-- (SN Computing Logical Extents -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To compute the bounding box of an 8-bit character string in a given font, use
-<function>XTextExtents</function>.
-<indexterm significance="preferred"><primary>XTextExtents</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XTextExtents</function></funcdef>
- <paramdef>XFontStruct<parameter> *font_struct</parameter></paramdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> nchars</parameter></paramdef>
- <paramdef>int<parameter> *direction_return</parameter></paramdef>
- <paramdef>int*font_ascent_return,<parameter> *font_descent_return</parameter></paramdef>
- <paramdef>XCharStruct<parameter> *overall_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_struct</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XFontStruct</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nchars</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>direction_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the value of the direction hint
-(<symbol>FontLeftToRight</symbol>
-or
-<symbol>FontRightToLeft</symbol>).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_ascent_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the font ascent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_descent_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the font descent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>overall_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the overall size in the specified
-<structname>XCharStruct</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To compute the bounding box of a 2-byte character string in a given font, use
-<function>XTextExtents16</function>.
-<indexterm significance="preferred"><primary>XTextExtents16</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XTextExtents16</function></funcdef>
- <paramdef>XFontStruct<parameter> *font_struct</parameter></paramdef>
- <paramdef>XChar2b<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> nchars</parameter></paramdef>
- <paramdef>int<parameter> *direction_return</parameter></paramdef>
- <paramdef>int*font_ascent_return,<parameter> *font_descent_return</parameter></paramdef>
- <paramdef>XCharStruct<parameter> *overall_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_struct</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XFontStruct</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nchars</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>direction_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the value of the direction hint
-(<symbol>FontLeftToRight</symbol>
-or
-<symbol>FontRightToLeft</symbol>).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_ascent_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the font ascent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_descent_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the font descent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>overall_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the overall size in the specified
-<structname>XCharStruct</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XTextExtents</function>
-and
-<function>XTextExtents16</function>
-functions
-perform the size computation locally and, thereby,
-avoid the round-trip overhead of
-<function>XQueryTextExtents</function>
-and
-<function>XQueryTextExtents16</function>.
-Both functions return an
-<structname>XCharStruct</structname>
-structure, whose members are set to the values as follows.
-</para>
-<para>
-<!-- .LP -->
-The ascent member is set to the maximum of the ascent metrics of all
-characters in the string.
-The descent member is set to the maximum of the descent metrics.
-The width member is set to the sum of the character-width metrics of all
-characters in the string.
-For each character in the string,
-let W be the sum of the character-width metrics of all characters preceding
-it in the string.
-Let L be the left-side-bearing metric of the character plus W.
-Let R be the right-side-bearing metric of the character plus W.
-The lbearing member is set to the minimum L of all characters in the string.
-The rbearing member is set to the maximum R.
-</para>
-<para>
-<!-- .LP -->
-For fonts defined with linear indexing rather than 2-byte matrix indexing,
-each
-<structname>XChar2b</structname>
-structure is interpreted as a 16-bit number with byte1 as the
-most significant byte.
-If the font has no defined default character,
-undefined characters in the string are taken to have all zero metrics.
-</para>
-</sect2>
-<sect2 id="Querying_Character_String_Sizes">
-<title>Querying Character String Sizes</title>
-<!-- .XS -->
-<!-- (SN Querying Character String Sizes -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To query the server for the bounding box of an 8-bit character string in a
-given font, use
-<function>XQueryTextExtents</function>.
-<indexterm significance="preferred"><primary>XQueryTextExtents</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XQueryTextExtents</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XID<parameter> font_ID</parameter></paramdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> nchars</parameter></paramdef>
- <paramdef>int<parameter> *direction_return</parameter></paramdef>
- <paramdef>int*font_ascent_return,<parameter> *font_descent_return</parameter></paramdef>
- <paramdef>XCharStruct<parameter> *overall_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_ID</emphasis>
- </term>
- <listitem>
- <para>
-Specifies either the font ID or the
-<type>GContext</type>
-ID that contains the font.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nchars</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>direction_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the value of the direction hint
-(<symbol>FontLeftToRight</symbol>
-or
-<symbol>FontRightToLeft</symbol>).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_ascent_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the font ascent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_descent_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the font descent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>overall_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the overall size in the specified
-<structname>XCharStruct</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To query the server for the bounding box of a 2-byte character string
-in a given font, use
-<function>XQueryTextExtents16</function>.
-<indexterm significance="preferred"><primary>XQueryTextExtents16</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XQueryTextExtents16</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XID<parameter> font_ID</parameter></paramdef>
- <paramdef>XChar2b<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> nchars</parameter></paramdef>
- <paramdef>int<parameter> *direction_return</parameter></paramdef>
- <paramdef>int*font_ascent_return,<parameter> *font_descent_return</parameter></paramdef>
- <paramdef>XCharStruct<parameter> *overall_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_ID</emphasis>
- </term>
- <listitem>
- <para>
-Specifies either the font ID or the
-<type>GContext</type>
-ID that contains the font.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nchars</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>direction_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the value of the direction hint
-(<symbol>FontLeftToRight</symbol>
-or
-<symbol>FontRightToLeft</symbol>).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_ascent_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the font ascent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_descent_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the font descent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>overall_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the overall size in the specified
-<structname>XCharStruct</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XQueryTextExtents</function>
-and
-<function>XQueryTextExtents16</function>
-functions return the bounding box of the specified 8-bit and 16-bit
-character string in the specified font or the font contained in the
-specified GC.
-These functions query the X server and, therefore, suffer the round-trip
-overhead that is avoided by
-<function>XTextExtents</function>
-and
-<function>XTextExtents16</function>.
-Both functions return a
-<structname>XCharStruct</structname>
-structure, whose members are set to the values as follows.
-</para>
-<para>
-<!-- .LP -->
-The ascent member is set to the maximum of the ascent metrics
-of all characters in the string.
-The descent member is set to the maximum of the descent metrics.
-The width member is set to the sum of the character-width metrics
-of all characters in the string.
-For each character in the string,
-let W be the sum of the character-width metrics of all characters preceding
-it in the string.
-Let L be the left-side-bearing metric of the character plus W.
-Let R be the right-side-bearing metric of the character plus W.
-The lbearing member is set to the minimum L of all characters in the string.
-The rbearing member is set to the maximum R.
-</para>
-<para>
-<!-- .LP -->
-For fonts defined with linear indexing rather than 2-byte matrix indexing,
-each
-<structname>XChar2b</structname>
-structure is interpreted as a 16-bit number with byte1 as the
-most significant byte.
-If the font has no defined default character,
-undefined characters in the string are taken to have all zero metrics.
-</para>
-<para>
-<!-- .LP -->
-Characters with all zero metrics are ignored.
-If the font has no defined default_char,
-the undefined characters in the string are also ignored.
-</para>
-<para>
-<!-- .LP -->
-<function>XQueryTextExtents</function>
-and
-<function>XQueryTextExtents16</function>
-can generate
-<errorname>BadFont</errorname>
-and
-<errorname>BadGC</errorname>
-errors.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Drawing_Text">
-<title>Drawing Text</title>
-<!-- .XS -->
-<!-- (SN Drawing Text -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This section discusses how to draw:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Complex text
- </para>
- </listitem>
- <listitem>
- <para>
-Text characters
- </para>
- </listitem>
- <listitem>
- <para>
-Image text characters
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The fundamental text functions
-<function>XDrawText</function>
-and
-<function>XDrawText16</function>
-use the following structures:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XTextItem</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-typedef struct {
- char *chars; /* pointer to string */
- int nchars; /* number of characters */
- int delta; /* delta between strings */
- Font font; /* Font to print it in, None don't change */
-} XTextItem;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XTextItem16</primary></indexterm>
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-typedef struct {
- XChar2b *chars; /* pointer to two-byte characters */
- int nchars; /* number of characters */
- int delta; /* delta between strings */
- Font font; /* font to print it in, None don't change */
-} XTextItem16;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If the font member is not
-<symbol>None</symbol>,
-the font is changed before printing and also is stored in the GC.
-If an error was generated during text drawing,
-the previous items may have been drawn.
-The baseline of the characters are drawn starting at the x and y
-coordinates that you pass in the text drawing functions.
-</para>
-<para>
-<!-- .LP -->
-For example, consider the background rectangle drawn by
-<function>XDrawImageString</function>.
-If you want the upper-left corner of the background rectangle
-to be at pixel coordinate (x,y), pass the (x,y + ascent)
-as the baseline origin coordinates to the text functions.
-The ascent is the font ascent, as given in the
-<structname>XFontStruct</structname>
-structure.
-If you want the lower-left corner of the background rectangle
-to be at pixel coordinate (x,y), pass the (x,y - descent + 1)
-as the baseline origin coordinates to the text functions.
-The descent is the font descent, as given in the
-<structname>XFontStruct</structname>
-structure.
-</para>
-<sect2 id="Drawing_Complex_Text">
-<title>Drawing Complex Text</title>
-<!-- .XS -->
-<!-- (SN Drawing Complex Text -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Text</primary><secondary>drawing</secondary></indexterm>
-<indexterm><primary>Drawing</primary><secondary>text items</secondary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-To draw 8-bit characters in a given drawable, use
-<function>XDrawText</function>.
-<indexterm significance="preferred"><primary>XDrawText</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawText</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>XTextItem<parameter> *items</parameter></paramdef>
- <paramdef>int<parameter> nitems</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy , which are relative to the origin of the specified drawable \ -->
-and define the origin of the first character
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>items</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of text items.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nitems</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of text items in the array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To draw 2-byte characters in a given drawable, use
-<function>XDrawText16</function>.
-<indexterm significance="preferred"><primary>XDrawText16</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawText16</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>XTextItem16<parameter> *items</parameter></paramdef>
- <paramdef>int<parameter> nitems</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy , which are relative to the origin of the specified drawable \ -->
-and define the origin of the first character
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>items</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of text items.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nitems</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of text items in the array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDrawText16</function>
-function is similar to
-<function>XDrawText</function>
-except that it uses 2-byte or 16-bit characters.
-Both functions allow complex spacing and font shifts between counted strings.
-</para>
-<para>
-<!-- .LP -->
-Each text item is processed in turn.
-A font member other than
-<symbol>None</symbol>
-in an item causes the font to be stored in the GC
-and used for subsequent text.
-A text element delta specifies an additional change
-in the position along the x axis before the string is drawn.
-The delta is always added to the character origin
-and is not dependent on any characteristics of the font.
-Each character image, as defined by the font in the GC, is treated as an
-additional mask for a fill operation on the drawable.
-The drawable is modified only where the font character has a bit set to 1.
-If a text item generates a
-<errorname>BadFont</errorname>
-error, the previous text items may have been drawn.
-</para>
-<para>
-<!-- .LP -->
-For fonts defined with linear indexing rather than 2-byte matrix indexing,
-each
-<structname>XChar2b</structname>
-structure is interpreted as a 16-bit number with byte1 as the
-most significant byte.
-</para>
-<para>
-<!-- .LP -->
-Both functions use these GC components:
-function, plane-mask, fill-style, font, subwindow-mode,
-clip-x-origin, clip-y-origin, and clip-mask.
-They also use these GC mode-dependent components:
-foreground, background, tile, stipple, tile-stipple-x-origin,
-and tile-stipple-y-origin.
-</para>
-<para>
-<!-- .LP -->
-<function>XDrawText</function>
-and
-<function>XDrawText16</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadFont</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadMatch</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Drawing_Text_Characters">
-<title>Drawing Text Characters</title>
-<!-- .XS -->
-<!-- (SN Drawing Text Characters -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Strings</primary><secondary>drawing</secondary></indexterm>
-<indexterm><primary>Drawing</primary><secondary>strings</secondary></indexterm>
-To draw 8-bit characters in a given drawable, use
-<function>XDrawString</function>.
-<indexterm significance="preferred"><primary>XDrawString</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawString</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> length</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy , which are relative to the origin of the specified drawable \ -->
-and define the origin of the first character
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>length</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the string argument.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To draw 2-byte characters in a given drawable, use
-<function>XDrawString16</function>.
-<indexterm significance="preferred"><primary>XDrawString16</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawString16</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>XChar2b<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> length</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy , which are relative to the origin of the specified drawable \ -->
-and define the origin of the first character
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>length</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the string argument.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Each character image, as defined by the font in the GC, is treated as an
-additional mask for a fill operation on the drawable.
-The drawable is modified only where the font character has a bit set to 1.
-For fonts defined with 2-byte matrix indexing
-and used with
-<function>XDrawString16</function>,
-each byte is used as a byte2 with a byte1 of zero.
-</para>
-<para>
-<!-- .LP -->
-Both functions use these GC components:
-function, plane-mask, fill-style, font, subwindow-mode, clip-x-origin,
-clip-y-origin, and clip-mask.
-They also use these GC mode-dependent components:
-foreground, background, tile, stipple, tile-stipple-x-origin,
-and tile-stipple-y-origin.
-</para>
-<para>
-<!-- .LP -->
-<function>XDrawString</function>
-and
-<function>XDrawString16</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadMatch</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Drawing_Image_Text_Characters">
-<title>Drawing Image Text Characters</title>
-<!-- .XS -->
-<!-- (SN Drawing Image Text Characters -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Image text</primary><secondary>drawing</secondary></indexterm>
-<indexterm><primary>Drawing</primary><secondary>image text</secondary></indexterm>
-Some applications, in particular terminal emulators, need to
-print image text in which both the foreground and background bits of
-each character are painted.
-This prevents annoying flicker on many displays.
-<indexterm><primary>XDrawImageString</primary></indexterm>
-<indexterm><primary>XDrawImageString16</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To draw 8-bit image text characters in a given drawable, use
-<function>XDrawImageString</function>.
-<indexterm significance="preferred"><primary>XDrawImageString</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawImageString</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> length</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy , which are relative to the origin of the specified drawable \ -->
-and define the origin of the first character
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>length</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the string argument.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To draw 2-byte image text characters in a given drawable, use
-<function>XDrawImageString16</function>.
-<indexterm significance="preferred"><primary>XDrawImageString16</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDrawImageString16</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>XChar2b<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> length</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy , which are relative to the origin of the specified drawable \ -->
-and define the origin of the first character
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>length</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the string argument.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDrawImageString16</function>
-function is similar to
-<function>XDrawImageString</function>
-except that it uses 2-byte or 16-bit characters.
-Both functions also use both the foreground and background pixels
-of the GC in the destination.
-</para>
-<para>
-<!-- .LP -->
-The effect is first to fill a
-destination rectangle with the background pixel defined in the GC and then
-to paint the text with the foreground pixel.
-The upper-left corner of the filled rectangle is at:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-[x, y - font-ascent]
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The width is:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-overall-width
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The height is:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-font-ascent + font-descent
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The overall-width, font-ascent, and font-descent
-are as would be returned by
-<function>XQueryTextExtents</function>
-using gc and string.
-The function and fill-style defined in the GC are ignored for these functions.
-The effective function is
-<symbol>GXcopy</symbol>,
-and the effective fill-style is
-<symbol>FillSolid</symbol>.
-</para>
-<para>
-<!-- .LP -->
-For fonts defined with 2-byte matrix indexing
-and used with
-<function>XDrawImageString</function>,
-each byte is used as a byte2 with a byte1 of zero.
-</para>
-<para>
-<!-- .LP -->
-Both functions use these GC components:
-plane-mask, foreground, background, font, subwindow-mode, clip-x-origin,
-clip-y-origin, and clip-mask.
-</para>
-<para>
-<!-- .LP -->
-<function>XDrawImageString</function>
-and
-<function>XDrawImageString16</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadMatch</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect2>
-</sect1>
-<sect1 id="Transferring_Images_between_Client_and_Server">
-<title>Transferring Images between Client and Server</title>
-<!-- .XS -->
-<!-- (SN Transferring Images between Client and Server -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to transfer images between a client
-and the server.
-Because the server may require diverse data formats,
-Xlib provides an image object that fully describes the data in memory
-and that provides for basic operations on that data.
-You should reference the data
-through the image object rather than referencing the data directly.
-However, some implementations of the Xlib library may efficiently deal with
-frequently used data formats by replacing
-functions in the procedure vector with special case functions.
-Supported operations include destroying the image, getting a pixel,
-storing a pixel, extracting a subimage of an image, and adding a constant
-to an image (see section 16.8).
-</para>
-<para>
-<!-- .LP -->
-All the image manipulation functions discussed in this section make use of
-the
-<structname>XImage</structname>
-structure,
-which describes an image as it exists in the client's memory.
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XImage</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 1i 3i -->
-<!-- .ta .5i 1i 3i -->
-typedef struct _XImage {
- int width, height; /* size of image */
- int xoffset; /* number of pixels offset in X direction */
- int format; /* XYBitmap, XYPixmap, ZPixmap */
- char *data; /* pointer to image data */
- int byte_order; /* data byte order, LSBFirst, MSBFirst */
- int bitmap_unit; /* quant. of scanline 8, 16, 32 */
- int bitmap_bit_order; /* LSBFirst, MSBFirst */
- int bitmap_pad; /* 8, 16, 32 either XY or ZPixmap */
- int depth; /* depth of image */
- int bytes_per_line; /* accelerator to next scanline */
- int bits_per_pixel; /* bits per pixel (ZPixmap) */
- unsigned long red_mask; /* bits in z arrangement */
- unsigned long green_mask;
- unsigned long blue_mask;
- XPointer obdata; /* hook for the object routines to hang on */
- struct funcs { /* image manipulation routines */
- struct _XImage *(*create_image)();
- int (*destroy_image)();
- unsigned long (*get_pixel)();
- int (*put_pixel)();
- struct _XImage *(*sub_image)();
- int (*add_pixel)();
- } f;
-} XImage;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To initialize the image manipulation routines of an image structure, use
-<function>XInitImage</function>.
-<indexterm significance="preferred"><primary>XInitImage</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XInitImage</function></funcdef>
- <paramdef>XImage<parameter> *image</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ximage</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the image.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XInitImage</function>
-function initializes the internal image manipulation routines of an
-image structure, based on the values of the various structure members.
-All fields other than the manipulation routines must already be initialized.
-If the bytes_per_line member is zero,
-<function>XInitImage</function>
-will assume the image data is contiguous in memory and set the
-bytes_per_line member to an appropriate value based on the other
-members; otherwise, the value of bytes_per_line is not changed.
-All of the manipulation routines are initialized to functions
-that other Xlib image manipulation functions need to operate on the
-type of image specified by the rest of the structure.
-</para>
-<para>
-<!-- .LP -->
-This function must be called for any image constructed by the client
-before passing it to any other Xlib function.
-Image structures created or returned by Xlib do not need to be
-initialized in this fashion.
-</para>
-<para>
-<!-- .LP -->
-This function returns a nonzero status if initialization of the
-structure is successful. It returns zero if it detected some error
-or inconsistency in the structure, in which case the image is not changed.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To combine an image with a rectangle of a drawable on the display,
-use
-<function>XPutImage</function>.
-<indexterm significance="preferred"><primary>XPutImage</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XPutImage</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>XImage<parameter> *image</parameter></paramdef>
- <paramdef>intsrc_x,<parameter> src_y</parameter></paramdef>
- <paramdef>intdest_x,<parameter> dest_y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>image</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the image you want combined with the rectangle.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src_x</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the offset in X from the left edge of the image defined
-by the
-<structname>XImage</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src_y</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the offset in Y from the top edge of the image defined
-by the
-<structname>XImage</structname>
-structure.
-<!-- .ds Dx , which are relative to the origin of the drawable \ -->
-and are the coordinates of the subimage
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Dx.
-<!-- .ds Wh \ of the subimage, which define the dimensions of the rectangle -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XPutImage</function>
-function
-combines an image with a rectangle of the specified drawable.
-The section of the image defined by the src_x, src_y, width, and height
-arguments is drawn on the specified part of the drawable.
-If
-<symbol>XYBitmap</symbol>
-format is used, the depth of the image must be one,
-or a
-<errorname>BadMatch</errorname>
-error results.
-The foreground pixel in the GC defines the source for the one bits in the image,
-and the background pixel defines the source for the zero bits.
-For
-<symbol>XYPixmap</symbol>
-and
-<symbol>ZPixmap</symbol>,
-the depth of the image must match the depth of the drawable,
-or a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-If the characteristics of the image (for example, byte_order and bitmap_unit)
-differ from what the server requires,
-<function>XPutImage</function>
-automatically makes the appropriate
-conversions.
-</para>
-<para>
-<!-- .LP -->
-This function uses these GC components:
-function, plane-mask, subwindow-mode, clip-x-origin, clip-y-origin,
-and clip-mask.
-It also uses these GC mode-dependent components:
-foreground and background.
-</para>
-<para>
-<!-- .LP -->
-<function>XPutImage</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-<errorname>BadMatch</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To return the contents of a rectangle in a given drawable on the display,
-use
-<function>XGetImage</function>.
-This function specifically supports rudimentary screen dumps.
-<indexterm significance="preferred"><primary>XGetImage</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XImage *<function>XGetImage</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>unsignedlong<parameter> plane_mask</parameter></paramdef>
- <paramdef>int<parameter> format</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
-<!-- .ds Xy , which are relative to the origin of the drawable \ -->
-and define the upper-left corner of the rectangle
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
-<!-- .ds Wh \ of the subimage, which define the dimensions of the rectangle -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>plane_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the plane mask.
-<!-- .\" *** JIM: NEED MORE INFO FOR THIS. *** -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the format for the image.
-You can pass
-<symbol>XYPixmap</symbol>
-or
-<symbol>ZPixmap</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetImage</function>
-function returns a pointer to an
-<structname>XImage</structname>
-structure.
-This structure provides you with the contents of the specified rectangle of
-the drawable in the format you specify.
-If the format argument is
-<symbol>XYPixmap</symbol>,
-the image contains only the bit planes you passed to the plane_mask argument.
-If the plane_mask argument only requests a subset of the planes of the
-display, the depth of the returned image will be the number of planes
-requested.
-If the format argument is
-<symbol>ZPixmap</symbol>,
-<function>XGetImage</function>
-returns as zero the bits in all planes not
-specified in the plane_mask argument.
-The function performs no range checking on the values in plane_mask and ignores
-extraneous bits.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetImage</function>
-returns the depth of the image to the depth member of the
-<structname>XImage</structname>
-structure.
-The depth of the image is as specified when the drawable was created,
-except when getting a subset of the planes in
-<symbol>XYPixmap</symbol>
-format, when the depth is given by the number of bits set to 1 in plane_mask.
-</para>
-<para>
-<!-- .LP -->
-If the drawable is a pixmap,
-the given rectangle must be wholly contained within the pixmap,
-or a
-<errorname>BadMatch</errorname>
-error results.
-If the drawable is a window,
-the window must be viewable,
-and it must be the case that if there were no inferiors or overlapping windows,
-the specified rectangle of the window would be fully visible on the screen
-and wholly contained within the outside edges of the window,
-or a
-<errorname>BadMatch</errorname>
-error results.
-Note that the borders of the window can be included and read with
-this request.
-If the window has backing-store, the backing-store contents are
-returned for regions of the window that are obscured by noninferior
-windows.
-If the window does not have backing-store,
-the returned contents of such obscured regions are undefined.
-The returned contents of visible regions of inferiors
-of a different depth than the specified window's depth are also undefined.
-The pointer cursor image is not included in the returned contents.
-If a problem occurs,
-<function>XGetImage</function>
-returns NULL.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetImage</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadMatch</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To copy the contents of a rectangle on the display
-to a location within a preexisting image structure, use
-<function>XGetSubImage</function>.
-<indexterm significance="preferred"><primary>XGetSubImage</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XImage *<function>XGetSubImage</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>unsignedlong<parameter> plane_mask</parameter></paramdef>
- <paramdef>int<parameter> format</parameter></paramdef>
- <paramdef>XImage<parameter> *dest_image</parameter></paramdef>
- <paramdef>intdest_x,<parameter> dest_y</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
-<!-- .ds Xy , which are relative to the origin of the drawable \ -->
-and define the upper-left corner of the rectangle
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
-<!-- .ds Wh \ of the subimage, which define the dimensions of the rectangle -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>plane_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the plane mask.
-<!-- .\" *** JIM: NEED MORE INFO FOR THIS. *** -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the format for the image.
-You can pass
-<symbol>XYPixmap</symbol>
-or
-<symbol>ZPixmap</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_image</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the destination image.
-<!-- .ds Dx , which are relative to the origin of the destination rectangle, \ -->
-specify its upper-left corner, and determine where the subimage \
-is placed in the destination image
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Dx.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetSubImage</function>
-function updates dest_image with the specified subimage in the same manner as
-<function>XGetImage</function>.
-If the format argument is
-<symbol>XYPixmap</symbol>,
-the image contains only the bit planes you passed to the plane_mask argument.
-If the format argument is
-<symbol>ZPixmap</symbol>,
-<function>XGetSubImage</function>
-returns as zero the bits in all planes not
-specified in the plane_mask argument.
-The function performs no range checking on the values in plane_mask and ignores
-extraneous bits.
-As a convenience,
-<function>XGetSubImage</function>
-returns a pointer to the same
-<structname>XImage</structname>
-structure specified by dest_image.
-</para>
-<para>
-<!-- .LP -->
-The depth of the destination
-<structname>XImage</structname>
-structure must be the same as that of the drawable.
-If the specified subimage does not fit at the specified location
-on the destination image, the right and bottom edges are clipped.
-If the drawable is a pixmap,
-the given rectangle must be wholly contained within the pixmap,
-or a
-<errorname>BadMatch</errorname>
-error results.
-If the drawable is a window,
-the window must be viewable,
-and it must be the case that if there were no inferiors or overlapping windows,
-the specified rectangle of the window would be fully visible on the screen
-and wholly contained within the outside edges of the window,
-or a
-<errorname>BadMatch</errorname>
-error results.
-If the window has backing-store,
-then the backing-store contents are returned for regions of the window
-that are obscured by noninferior windows.
-If the window does not have backing-store,
-the returned contents of such obscured regions are undefined.
-The returned contents of visible regions of inferiors
-of a different depth than the specified window's depth are also undefined.
-If a problem occurs,
-<function>XGetSubImage</function>
-returns NULL.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetSubImage</function>
-can generate
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-<errorname>BadMatch</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-<!-- .bp -->
-
-
-</para>
-</sect1>
-</chapter>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<chapter id="graphics_functions">
+<title>Graphics Functions</title>
+<para>
+Once you have established a connection to a display, you can use the Xlib graphics functions to:
+</para>
+<itemizedlist>
+ <listitem><para>Clear and copy areas</para></listitem>
+ <listitem><para>Draw points, lines, rectangles, and arcs</para></listitem>
+ <listitem><para>Fill areas</para></listitem>
+ <listitem><para>Manipulate fonts</para></listitem>
+ <listitem><para>Draw text</para></listitem>
+ <listitem><para>Transfer images between clients and the server</para></listitem>
+</itemizedlist>
+<para>
+If the same drawable and GC is used for each call, Xlib batches back-to-back
+calls to XDrawPoint, XDrawLine, XDrawRectangle, XFillArc, and XFillRectangle.
+Note that this reduces the total number of requests sent to the server.
+</para>
+<sect1 id="Clearing_Areas">
+<title>Clearing Areas</title>
+<!-- .XS -->
+<!-- (SN Clearing Areas -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to clear an area or the entire window.
+Because pixmaps do not have defined backgrounds,
+they cannot be filled by using the functions described in this section.
+Instead, to accomplish an analogous operation on a pixmap,
+you should use
+<function>XFillRectangle</function>,
+which sets the pixmap to a known value.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To clear a rectangular area of a given window, use
+<function>XClearArea</function>.
+<indexterm><primary>Areas</primary><secondary>clearing</secondary></indexterm>
+<indexterm><primary>Clearing</primary><secondary>areas</secondary></indexterm>
+<indexterm significance="preferred"><primary>XClearArea</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcleararea'>
+<funcprototype>
+ <funcdef><function>XClearArea</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>Bool<parameter> exposures</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+<!-- .ds Xy , which are relative to the origin of the window \ -->
+and specify the upper-left corner of the rectangle
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+<!-- .ds Wh , which are the dimensions of the rectangle -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>exposures</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value that indicates if
+<symbol>Expose</symbol>
+events are to be generated.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XClearArea</function>
+function paints a rectangular area in the specified window according to the
+specified dimensions with the window's background pixel or pixmap.
+The subwindow-mode effectively is
+<symbol>ClipByChildren</symbol>.
+If width is zero, it
+is replaced with the current width of the window minus x.
+If height is
+zero, it is replaced with the current height of the window minus y.
+If the window has a defined background tile,
+the rectangle clipped by any children is filled with this tile.
+If the window has
+background
+<symbol>None</symbol>,
+the contents of the window are not changed.
+In either
+case, if exposures is
+<symbol>True</symbol>,
+one or more
+<symbol>Expose</symbol>
+events are generated for regions of the rectangle that are either visible or are
+being retained in a backing store.
+If you specify a window whose class is
+<symbol>InputOnly</symbol>,
+a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XClearArea</function>
+can generate
+<errorname>BadMatch</errorname>,
+<errorname>BadValue</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To clear the entire area in a given window, use
+<function>XClearWindow</function>.
+<indexterm><primary>Window</primary><secondary>clearing</secondary></indexterm>
+<indexterm><primary>Clearing</primary><secondary>windows</secondary></indexterm>
+<indexterm significance="preferred"><primary>XClearWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xclearwindow'>
+<funcprototype>
+ <funcdef><function>XClearWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XClearWindow</function>
+function clears the entire area in the specified window and is
+equivalent to
+<function>XClearArea</function>
+(display, w, 0, 0, 0, 0,
+<symbol>False</symbol>).
+If the window has a defined background tile, the rectangle is tiled with a
+plane-mask of all ones and
+<symbol>GXcopy</symbol>
+function.
+If the window has
+background
+<symbol>None</symbol>,
+the contents of the window are not changed.
+If you specify a window whose class is
+<symbol>InputOnly</symbol>,
+a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XClearWindow</function>
+can generate
+<errorname>BadMatch</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect1>
+<sect1 id="Copying_Areas">
+<title>Copying Areas</title>
+<!-- .XS -->
+<!-- (SN Copying Areas -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to copy an area or a bit plane.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To copy an area between drawables of the same
+root and depth, use
+<function>XCopyArea</function>.
+<indexterm><primary>Areas</primary><secondary>copying</secondary></indexterm>
+<indexterm><primary>Copying</primary><secondary>areas</secondary></indexterm>
+<indexterm significance="preferred"><primary>XCopyArea</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcopyarea'>
+<funcprototype>
+ <funcdef><function>XCopyArea</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawablesrc,<parameter> dest</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intsrc_x,<parameter> src_y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>intdest_x,<parameter> dest_y</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the source and destination rectangles to be combined.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src_x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src_y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates,
+which are relative to the origin of the source rectangle
+and specify its upper-left corner.
+<!-- .ds Wh , which are the dimensions of both the source \ -->
+and destination rectangles
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+<!-- .ds Dx , which are relative to the origin of the destination rectangle \ -->
+and specify its upper-left corner
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Dx.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCopyArea</function>
+function combines the specified rectangle of src with the specified rectangle
+of dest.
+The drawables must have the same root and depth,
+or a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+If regions of the source rectangle are obscured and have not been
+retained in backing store
+or if regions outside the boundaries of the source drawable are specified,
+those regions are not copied.
+Instead, the
+following occurs on all corresponding destination regions that are either
+visible or are retained in backing store.
+If the destination is a window with a background other than
+<symbol>None</symbol>,
+corresponding regions
+of the destination are tiled with that background
+(with plane-mask of all ones and
+<symbol>GXcopy</symbol>
+function).
+Regardless of tiling or whether the destination is a window or a pixmap,
+if graphics-exposures is
+<symbol>True</symbol>,
+then
+<symbol>GraphicsExpose</symbol>
+events for all corresponding destination regions are generated.
+If graphics-exposures is
+<symbol>True</symbol>
+but no
+<symbol>GraphicsExpose</symbol>
+events are generated, a
+<symbol>NoExpose</symbol>
+event is generated.
+Note that by default graphics-exposures is
+<symbol>True</symbol>
+in new GCs.
+</para>
+<para>
+<!-- .LP -->
+This function uses these GC components: function, plane-mask,
+subwindow-mode, graphics-exposures, clip-x-origin,
+clip-y-origin, and clip-mask.
+</para>
+<para>
+<!-- .LP -->
+<function>XCopyArea</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadMatch</errorname>
+errors.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To copy a single bit plane of a given drawable, use
+<function>XCopyPlane</function>.
+<indexterm><primary>Plane</primary><secondary>copying</secondary></indexterm>
+<indexterm><primary>Copying</primary><secondary>planes</secondary></indexterm>
+<indexterm significance="preferred"><primary>XCopyPlane</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcopyplane'>
+<funcprototype>
+ <funcdef><function>XCopyPlane</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawablesrc,<parameter> dest</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intsrc_x,<parameter> src_y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>intdest_x,<parameter> dest_y</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> plane</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the source and destination rectangles to be combined.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src_x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src_y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates,
+which are relative to the origin of the source rectangle
+and specify its upper-left corner.
+<!-- .ds Wh , which are the dimensions of both the source and destination rectangles -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+<!-- .ds Dx , which are relative to the origin of the destination rectangle \ -->
+and specify its upper-left corner
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Dx.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>plane</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the bit plane.
+You must set exactly one bit to 1.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCopyPlane</function>
+function uses a single bit plane of the specified source rectangle
+combined with the specified GC to modify the specified rectangle of dest.
+The drawables must have the same root but need not have the same depth.
+If the drawables do not have the same root, a
+<errorname>BadMatch</errorname>
+error results.
+If plane does not have exactly one bit set to 1 and the value of plane
+is not less than %2 sup n%, where <emphasis remap='I'>n</emphasis> is the depth of src, a
+<errorname>BadValue</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+Effectively,
+<function>XCopyPlane</function>
+forms a pixmap of the same depth as the rectangle of dest and with a
+size specified by the source region.
+It uses the foreground/background pixels in the GC (foreground
+everywhere the bit plane in src contains a bit set to 1,
+background everywhere the bit plane in src contains a bit set to 0)
+and the equivalent of a
+<systemitem>CopyArea</systemitem>
+protocol request is performed with all the same exposure semantics.
+This can also be thought of as using the specified region of the source
+bit plane as a stipple with a fill-style of
+<symbol>FillOpaqueStippled</symbol>
+for filling a rectangular area of the destination.
+</para>
+<para>
+<!-- .LP -->
+This function uses these GC components: function, plane-mask, foreground,
+background, subwindow-mode, graphics-exposures, clip-x-origin, clip-y-origin,
+and clip-mask.
+</para>
+<para>
+<!-- .LP -->
+<function>XCopyPlane</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+<errorname>BadMatch</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+</sect1>
+<sect1 id="Drawing_Points_Lines_Rectangles_and_Arcs">
+<title>Drawing Points, Lines, Rectangles, and Arcs</title>
+<!-- .XS -->
+<!-- (SN Drawing Points, Lines, Rectangles, and Arcs -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to draw:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+A single point or multiple points
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A single line or multiple lines
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A single rectangle or multiple rectangles
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A single arc or multiple arcs
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Some of the functions described in the following sections
+use these structures:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XSegment</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i -->
+<!-- .ta .5i -->
+typedef struct {
+ short x1, y1, x2, y2;
+} XSegment;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>XPoint</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i -->
+<!-- .ta .5i -->
+typedef struct {
+ short x, y;
+} XPoint;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>XRectangle</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i -->
+<!-- .ta .5i -->
+typedef struct {
+ short x, y;
+ unsigned short width, height;
+} XRectangle;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>XArc</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+typedef struct {
+ short x, y;
+ unsigned short width, height;
+ short angle1, angle2; /* Degrees * 64 */
+} XArc;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+All x and y members are signed integers.
+The width and height members are 16-bit unsigned integers.
+You should be careful not to generate coordinates and sizes
+out of the 16-bit ranges, because the protocol only has 16-bit fields
+for these values.
+</para>
+<sect2 id="Drawing_Single_and_Multiple_Points">
+<title>Drawing Single and Multiple Points</title>
+<!-- .XS -->
+<!-- (SN Drawing Single and Multiple Points -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Points</primary><secondary>drawing</secondary></indexterm>
+<indexterm><primary>Drawing</primary><secondary>points</secondary></indexterm>
+<indexterm><primary>XDrawPoints</primary></indexterm>
+<indexterm><primary>XDrawPoint</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+To draw a single point in a given drawable, use
+<function>XDrawPoint</function>.
+<indexterm significance="preferred"><primary>XDrawPoint</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawpoint'>
+<funcprototype>
+ <funcdef><function>XDrawPoint</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates where you want the point drawn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To draw multiple points in a given drawable, use
+<function>XDrawPoints</function>.
+<indexterm significance="preferred"><primary>XDrawPoints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawpoints'>
+<funcprototype>
+ <funcdef><function>XDrawPoints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>XPoint<parameter> *points</parameter></paramdef>
+ <paramdef>int<parameter> npoints</parameter></paramdef>
+ <paramdef>int<parameter> mode</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>points</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of points.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>npoints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of points in the array.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the coordinate mode.
+You can pass
+<symbol>CoordModeOrigin</symbol>
+or
+<symbol>CoordModePrevious</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDrawPoint</function>
+function uses the foreground pixel and function components of the
+GC to draw a single point into the specified drawable;
+<function>XDrawPoints</function>
+draws multiple points this way.
+<symbol>CoordModeOrigin</symbol>
+treats all coordinates as relative to the origin,
+and
+<symbol>CoordModePrevious</symbol>
+treats all coordinates after the first as relative to the previous point.
+<function>XDrawPoints</function>
+draws the points in the order listed in the array.
+</para>
+<para>
+<!-- .LP -->
+Both functions use these GC components: function, plane-mask,
+foreground, subwindow-mode, clip-x-origin, clip-y-origin, and clip-mask.
+</para>
+<para>
+<!-- .LP -->
+<function>XDrawPoint</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadMatch</errorname>
+errors.
+<function>XDrawPoints</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+<errorname>BadMatch</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Drawing_Single_and_Multiple_Lines">
+<title>Drawing Single and Multiple Lines</title>
+<!-- .XS -->
+<!-- (SN Drawing Single and Multiple Lines -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Lines</primary><secondary>drawing</secondary></indexterm>
+<indexterm><primary>Drawing</primary><secondary>lines</secondary></indexterm>
+<indexterm><primary>XDrawLine</primary></indexterm>
+<indexterm><primary>XDrawLines</primary></indexterm>
+<indexterm><primary>Polygons</primary><secondary>drawing</secondary></indexterm>
+<indexterm><primary>Drawing</primary><secondary>polygons</secondary></indexterm>
+<indexterm><primary>XDrawSegments</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+To draw a single line between two points in a given drawable, use
+<function>XDrawLine</function>.
+<indexterm significance="preferred"><primary>XDrawLine</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawline'>
+<funcprototype>
+ <funcdef><function>XDrawLine</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx1,y1,x2,<parameter> y2</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x1</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y1</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x2</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y2</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the points (x1, y1) and (x2, y2) to be connected.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To draw multiple lines in a given drawable, use
+<function>XDrawLines</function>.
+<indexterm significance="preferred"><primary>XDrawLines</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawlines'>
+<funcprototype>
+ <funcdef><function>XDrawLines</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>XPoint<parameter> *points</parameter></paramdef>
+ <paramdef>int<parameter> npoints</parameter></paramdef>
+ <paramdef>int<parameter> mode</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>points</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of points.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>npoints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of points in the array.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the coordinate mode.
+You can pass
+<symbol>CoordModeOrigin</symbol>
+or
+<symbol>CoordModePrevious</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To draw multiple, unconnected lines in a given drawable,
+use
+<function>XDrawSegments</function>.
+<indexterm significance="preferred"><primary>XDrawSegments</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawsegments'>
+<funcprototype>
+ <funcdef><function>XDrawSegments</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>XSegment<parameter> *segments</parameter></paramdef>
+ <paramdef>int<parameter> nsegments</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>segments</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of segments.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nsegments</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of segments in the array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDrawLine</function>
+function uses the components of the specified GC to
+draw a line between the specified set of points (x1, y1) and (x2, y2).
+It does not perform joining at coincident endpoints.
+For any given line,
+<function>XDrawLine</function>
+does not draw a pixel more than once.
+If lines intersect, the intersecting pixels are drawn multiple times.
+</para>
+<para>
+<!-- .LP -->
+The
+<function>XDrawLines</function>
+function uses the components of the specified GC to draw
+npoints-1 lines between each pair of points (point[i], point[i+1])
+in the array of
+<structname>XPoint</structname>
+structures.
+It draws the lines in the order listed in the array.
+The lines join correctly at all intermediate points, and if the first and last
+points coincide, the first and last lines also join correctly.
+For any given line,
+<function>XDrawLines</function>
+does not draw a pixel more than once.
+If thin (zero line-width) lines intersect,
+the intersecting pixels are drawn multiple times.
+If wide lines intersect, the intersecting pixels are drawn only once, as though
+the entire
+<systemitem>PolyLine</systemitem>
+protocol request were a single, filled shape.
+<symbol>CoordModeOrigin</symbol>
+treats all coordinates as relative to the origin,
+and
+<symbol>CoordModePrevious</symbol>
+treats all coordinates after the first as relative to the previous point.
+</para>
+<para>
+<!-- .LP -->
+The
+<function>XDrawSegments</function>
+function draws multiple, unconnected lines.
+For each segment,
+<function>XDrawSegments</function>
+draws a
+line between (x1, y1) and (x2, y2).
+It draws the lines in the order listed in the array of
+<structname>XSegment</structname>
+structures and does not perform joining at coincident endpoints.
+For any given line,
+<function>XDrawSegments</function>
+does not draw a pixel more than once.
+If lines intersect, the intersecting pixels are drawn multiple times.
+</para>
+<para>
+<!-- .LP -->
+All three functions use these GC components:
+function, plane-mask, line-width,
+line-style, cap-style, fill-style, subwindow-mode,
+clip-x-origin, clip-y-origin, and clip-mask.
+The
+<function>XDrawLines</function>
+function also uses the join-style GC component.
+All three functions also use these GC mode-dependent components:
+foreground, background, tile, stipple, tile-stipple-x-origin,
+tile-stipple-y-origin, dash-offset, and dash-list.
+</para>
+<para>
+<!-- .LP -->
+<function>XDrawLine</function>,
+<function>XDrawLines</function>,
+and
+<function>XDrawSegments</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadMatch</errorname>
+errors.
+<function>XDrawLines</function>
+also can generate
+<errorname>BadValue</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Drawing_Single_and_Multiple_Rectangles_">
+<title>Drawing Single and Multiple Rectangles </title>
+<!-- .XS -->
+<!-- (SN Drawing Single and Multiple Rectangles -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Rectangles</primary><secondary>drawing</secondary></indexterm>
+<indexterm><primary>Drawing</primary><secondary>rectangles</secondary></indexterm>
+<indexterm><primary>XDrawRectangle</primary></indexterm>
+<indexterm><primary>XDrawRectangles</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+To draw the outline of a single rectangle in a given drawable, use
+<function>XDrawRectangle</function>.
+<indexterm significance="preferred"><primary>XDrawRectangle</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawrectangle'>
+<funcprototype>
+ <funcdef><function>XDrawRectangle</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy , which specify the upper-left corner of the rectangle -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+<!-- .ds Wh , which specify the dimensions of the rectangle -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To draw the outline of multiple rectangles
+in a given drawable, use
+<function>XDrawRectangles</function>.
+<indexterm significance="preferred"><primary>XDrawRectangles</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawrectangles'>
+<funcprototype>
+ <funcdef><function>XDrawRectangles</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>XRectangle<parameter> rectangles[]</parameter></paramdef>
+ <paramdef>int<parameter> nrectangles</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rectangles</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of rectangles.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nrectangles</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of rectangles in the array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDrawRectangle</function>
+and
+<function>XDrawRectangles</function>
+functions draw the outlines of the specified rectangle or rectangles as
+if a five-point
+<systemitem>PolyLine</systemitem>
+protocol request were specified for each rectangle:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+[x,y] [x+width,y] [x+width,y+height] [x,y+height] [x,y]
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+For the specified rectangle or rectangles,
+these functions do not draw a pixel more than once.
+<function>XDrawRectangles</function>
+draws the rectangles in the order listed in the array.
+If rectangles intersect,
+the intersecting pixels are drawn multiple times.
+</para>
+<para>
+<!-- .LP -->
+Both functions use these GC components:
+function, plane-mask, line-width,
+line-style, cap-style, join-style, fill-style,
+subwindow-mode, clip-x-origin, clip-y-origin, and clip-mask.
+They also use these GC mode-dependent components:
+foreground, background, tile, stipple, tile-stipple-x-origin,
+tile-stipple-y-origin, dash-offset, and dash-list.
+</para>
+<para>
+<!-- .LP -->
+<function>XDrawRectangle</function>
+and
+<function>XDrawRectangles</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadMatch</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Drawing_Single_and_Multiple_Arcs">
+<title>Drawing Single and Multiple Arcs</title>
+<!-- .XS -->
+<!-- (SN Drawing Single and Multiple Arcs -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Drawing</primary><secondary>arcs</secondary></indexterm>
+<indexterm><primary>XDrawArc</primary></indexterm>
+<indexterm><primary>Arcs</primary><secondary>drawing</secondary></indexterm>
+<indexterm><primary>XDrawArcs</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To draw a single arc in a given drawable, use
+<function>XDrawArc</function>.
+<indexterm significance="preferred"><primary>XDrawArc</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawarc'>
+<funcprototype>
+ <funcdef><function>XDrawArc</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>intangle1,<parameter> angle2</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy , which are relative to the origin of the drawable \ -->
+and specify the upper-left corner of the bounding rectangle
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+<!-- .ds Wh , which are the major and minor axes of the arc -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>angle1</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the start of the arc relative to the three-o'clock position
+from the center, in units of degrees * 64.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>angle2</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the path and extent of the arc relative to the start of the
+arc, in units of degrees * 64.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To draw multiple arcs in a given drawable, use
+<function>XDrawArcs</function>.
+<indexterm significance="preferred"><primary>XDrawArcs</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawarcs'>
+<funcprototype>
+ <funcdef><function>XDrawArcs</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>XArc<parameter> *arcs</parameter></paramdef>
+ <paramdef>int<parameter> narcs</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>arcs</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of arcs.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>narcs</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of arcs in the array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .EQ -->
+delim %%
+<!-- .EN -->
+<function>XDrawArc</function>
+draws a single circular or elliptical arc, and
+<function>XDrawArcs</function>
+draws multiple circular or elliptical arcs.
+Each arc is specified by a rectangle and two angles.
+The center of the circle or ellipse is the center of the
+rectangle, and the major and minor axes are specified by the width and height.
+Positive angles indicate counterclockwise motion,
+and negative angles indicate clockwise motion.
+If the magnitude of angle2 is greater than 360 degrees,
+<function>XDrawArc</function>
+or
+<function>XDrawArcs</function>
+truncates it to 360 degrees.
+</para>
+<para>
+<!-- .LP -->
+For an arc specified as %[ ~x, ~y, ~width , ~height, ~angle1, ~angle2 ]%,
+the origin of the major and minor axes is at
+% [ x +^ {width over 2} , ~y +^ {height over 2} ]%,
+and the infinitely thin path describing the entire circle or ellipse
+intersects the horizontal axis at % [ x, ~y +^ {height over 2} ]% and
+% [ x +^ width , ~y +^ { height over 2 }] %
+and intersects the vertical axis at % [ x +^ { width over 2 } , ~y ]% and
+% [ x +^ { width over 2 }, ~y +^ height ]%.
+These coordinates can be fractional
+and so are not truncated to discrete coordinates.
+The path should be defined by the ideal mathematical path.
+For a wide line with line-width lw,
+the bounding outlines for filling are given
+by the two infinitely thin paths consisting of all points whose perpendicular
+distance from the path of the circle/ellipse is equal to lw/2
+(which may be a fractional value).
+The cap-style and join-style are applied the same as for a line
+corresponding to the tangent of the circle/ellipse at the endpoint.
+</para>
+<para>
+<!-- .LP -->
+For an arc specified as % [ ~x, ~y, ~width, ~height, ~angle1, ~angle2 ]%,
+the angles must be specified
+in the effectively skewed coordinate system of the ellipse (for a
+circle, the angles and coordinate systems are identical). The
+relationship between these angles and angles expressed in the normal
+coordinate system of the screen (as measured with a protractor) is as
+follows:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+% roman "skewed-angle" ~ = ~ atan left ( tan ( roman "normal-angle" )
+ * width over height right ) +^ adjust%
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The skewed-angle and normal-angle are expressed in radians (rather
+than in degrees scaled by 64) in the range % [ 0 , ~2 pi ]% and where atan
+returns a value in the range % [ - pi over 2 , ~pi over 2 ] %
+and adjust is:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA 1i 2i -->
+<!-- .ta 1i 2i -->
+%0% for normal-angle in the range % [ 0 , ~pi over 2 ]%
+%pi% for normal-angle in the range % [ pi over 2 , ~{3 pi} over 2 ]%
+%2 pi% for normal-angle in the range % [ {3 pi} over 2 , ~2 pi ]%
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+For any given arc,
+<function>XDrawArc</function>
+and
+<function>XDrawArcs</function>
+do not draw a pixel more than once.
+If two arcs join correctly and if the line-width is greater than zero
+and the arcs intersect,
+<function>XDrawArc</function>
+and
+<function>XDrawArcs</function>
+do not draw a pixel more than once.
+Otherwise,
+the intersecting pixels of intersecting arcs are drawn multiple times.
+Specifying an arc with one endpoint and a clockwise extent draws the same pixels
+as specifying the other endpoint and an equivalent counterclockwise extent,
+except as it affects joins.
+</para>
+<para>
+<!-- .LP -->
+If the last point in one arc coincides with the first point in the following
+arc, the two arcs will join correctly.
+If the first point in the first arc coincides with the last point in the last
+arc, the two arcs will join correctly.
+By specifying one axis to be zero, a horizontal or vertical line can be
+drawn.
+Angles are computed based solely on the coordinate system and ignore the
+aspect ratio.
+</para>
+<para>
+<!-- .LP -->
+Both functions use these GC components:
+function, plane-mask, line-width, line-style, cap-style, join-style,
+fill-style, subwindow-mode, clip-x-origin, clip-y-origin, and clip-mask.
+They also use these GC mode-dependent components:
+foreground, background, tile, stipple, tile-stipple-x-origin,
+tile-stipple-y-origin, dash-offset, and dash-list.
+</para>
+<para>
+<!-- .LP -->
+<function>XDrawArc</function>
+and
+<function>XDrawArcs</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadMatch</errorname>
+errors.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Filling_Areas">
+<title>Filling Areas</title>
+<!-- .XS -->
+<!-- (SN Filling Areas -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to fill:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+A single rectangle or multiple rectangles
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A single polygon
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A single arc or multiple arcs
+ </para>
+ </listitem>
+</itemizedlist>
+<sect2 id="Filling_Single_and_Multiple_Rectangles">
+<title>Filling Single and Multiple Rectangles</title>
+<!-- .XS -->
+<!-- (SN Filling Single and Multiple Rectangles -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Filling</primary><secondary>rectangles</secondary></indexterm>
+<indexterm><primary>XFillRectangle</primary></indexterm>
+<indexterm><primary>Rectangle</primary><secondary>filling</secondary></indexterm>
+<indexterm><primary>XFillRectangles</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To fill a single rectangular area in a given drawable, use
+<function>XFillRectangle</function>.
+<indexterm significance="preferred"><primary>XFillRectangle</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfillrectangle'>
+<funcprototype>
+ <funcdef><function>XFillRectangle</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy , which are relative to the origin of the drawable \ -->
+and specify the upper-left corner of the rectangle
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+<!-- .ds Wh , which are the dimensions of the rectangle to be filled -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To fill multiple rectangular areas in a given drawable, use
+<function>XFillRectangles</function>.
+<indexterm significance="preferred"><primary>XFillRectangles</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfillrectangles'>
+<funcprototype>
+ <funcdef><function>XFillRectangles</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *rectangles</parameter></paramdef>
+ <paramdef>int<parameter> nrectangles</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rectangles</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of rectangles.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nrectangles</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of rectangles in the array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFillRectangle</function>
+and
+<function>XFillRectangles</function>
+functions fill the specified rectangle or rectangles
+as if a four-point
+<systemitem>FillPolygon</systemitem>
+protocol request were specified for each rectangle:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+[x,y] [x+width,y] [x+width,y+height] [x,y+height]
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+Each function uses the x and y coordinates,
+width and height dimensions, and GC you specify.
+</para>
+<para>
+<!-- .LP -->
+<function>XFillRectangles</function>
+fills the rectangles in the order listed in the array.
+For any given rectangle,
+<function>XFillRectangle</function>
+and
+<function>XFillRectangles</function>
+do not draw a pixel more than once.
+If rectangles intersect, the intersecting pixels are
+drawn multiple times.
+</para>
+<para>
+<!-- .LP -->
+Both functions use these GC components:
+function, plane-mask, fill-style, subwindow-mode,
+clip-x-origin, clip-y-origin, and clip-mask.
+They also use these GC mode-dependent components:
+foreground, background, tile, stipple, tile-stipple-x-origin,
+and tile-stipple-y-origin.
+</para>
+<para>
+<!-- .LP -->
+<function>XFillRectangle</function>
+and
+<function>XFillRectangles</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadMatch</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Filling_a_Single_Polygon">
+<title>Filling a Single Polygon</title>
+<!-- .XS -->
+<!-- (SN Filling a Single Polygon -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To fill a polygon area in a given drawable, use
+<function>XFillPolygon</function>.
+<indexterm><primary>Polygons</primary><secondary>filling</secondary></indexterm>
+<indexterm><primary>Filling</primary><secondary>polygon</secondary></indexterm>
+<indexterm significance="preferred"><primary>XFillPolygon</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfillpolygon'>
+<funcprototype>
+ <funcdef><function>XFillPolygon</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>XPoint<parameter> *points</parameter></paramdef>
+ <paramdef>int<parameter> npoints</parameter></paramdef>
+ <paramdef>int<parameter> shape</parameter></paramdef>
+ <paramdef>int<parameter> mode</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>points</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of points.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>npoints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of points in the array.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>shape</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a shape that helps the server to improve performance.
+You can pass
+<symbol>Complex</symbol>,
+<symbol>Convex</symbol>,
+or
+<symbol>Nonconvex</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the coordinate mode.
+You can pass
+<symbol>CoordModeOrigin</symbol>
+or
+<symbol>CoordModePrevious</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XFillPolygon</function>
+fills the region closed by the specified path.
+The path is closed
+automatically if the last point in the list does not coincide with the
+first point.
+<function>XFillPolygon</function>
+does not draw a pixel of the region more than once.
+<symbol>CoordModeOrigin</symbol>
+treats all coordinates as relative to the origin,
+and
+<symbol>CoordModePrevious</symbol>
+treats all coordinates after the first as relative to the previous point.
+</para>
+<para>
+<!-- .LP -->
+Depending on the specified shape, the following occurs:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+If shape is
+<symbol>Complex</symbol>,
+the path may self-intersect.
+Note that contiguous coincident points in the path are not treated
+as self-intersection.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If shape is
+<symbol>Convex</symbol>,
+for every pair of points inside the polygon,
+the line segment connecting them does not intersect the path.
+If known by the client,
+specifying
+<symbol>Convex</symbol>
+can improve performance.
+If you specify
+<symbol>Convex</symbol>
+for a path that is not convex,
+the graphics results are undefined.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If shape is
+<symbol>Nonconvex</symbol>,
+the path does not self-intersect, but the shape is not
+wholly convex.
+If known by the client,
+specifying
+<symbol>Nonconvex</symbol>
+instead of
+<symbol>Complex</symbol>
+may improve performance.
+If you specify
+<symbol>Nonconvex</symbol>
+for a self-intersecting path, the graphics results are undefined.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The fill-rule of the GC controls the filling behavior of
+self-intersecting polygons.
+</para>
+<para>
+<!-- .LP -->
+This function uses these GC components:
+function, plane-mask, fill-style, fill-rule, subwindow-mode, clip-x-origin,
+clip-y-origin, and clip-mask.
+It also uses these GC mode-dependent components:
+foreground, background, tile, stipple, tile-stipple-x-origin,
+and tile-stipple-y-origin.
+</para>
+<para>
+<!-- .LP -->
+<function>XFillPolygon</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+<errorname>BadMatch</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Filling_Single_and_Multiple_Arcs">
+<title>Filling Single and Multiple Arcs</title>
+<!-- .XS -->
+<!-- (SN Filling Single and Multiple Arcs -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>XFillArc</primary></indexterm>
+<indexterm><primary>Arcs</primary><secondary>filling</secondary></indexterm>
+<indexterm><primary>Filling</primary><secondary>arcs</secondary></indexterm>
+To fill a single arc in a given drawable, use
+<function>XFillArc</function>.
+<indexterm significance="preferred"><primary>XFillArc</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfillarc'>
+<funcprototype>
+ <funcdef><function>XFillArc</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>intangle1,<parameter> angle2</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy , which are relative to the origin of the drawable \ -->
+and specify the upper-left corner of the bounding rectangle
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+<!-- .ds Wh , which are the major and minor axes of the arc -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>angle1</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the start of the arc relative to the three-o'clock position
+from the center, in units of degrees * 64.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>angle2</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the path and extent of the arc relative to the start of the
+arc, in units of degrees * 64.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To fill multiple arcs in a given drawable, use
+<function>XFillArcs</function>.
+<indexterm significance="preferred"><primary>XFillArcs</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfillarcs'>
+<funcprototype>
+ <funcdef><function>XFillArcs</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>XArc<parameter> *arcs</parameter></paramdef>
+ <paramdef>int<parameter> narcs</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>arcs</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of arcs.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>narcs</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of arcs in the array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+For each arc,
+<function>XFillArc</function>
+or
+<function>XFillArcs</function>
+fills the region closed by the infinitely thin path
+described by the specified arc and, depending on the
+arc-mode specified in the GC, one or two line segments.
+For
+<symbol>ArcChord</symbol>,
+the single line segment joining the endpoints of the arc is used.
+For
+<symbol>ArcPieSlice</symbol>,
+the two line segments joining the endpoints of the arc with the center
+point are used.
+<function>XFillArcs</function>
+fills the arcs in the order listed in the array.
+For any given arc,
+<function>XFillArc</function>
+and
+<function>XFillArcs</function>
+do not draw a pixel more than once.
+If regions intersect,
+the intersecting pixels are drawn multiple times.
+</para>
+<para>
+<!-- .LP -->
+Both functions use these GC components:
+function, plane-mask, fill-style, arc-mode, subwindow-mode, clip-x-origin,
+clip-y-origin, and clip-mask.
+They also use these GC mode-dependent components:
+foreground, background, tile, stipple, tile-stipple-x-origin,
+and tile-stipple-y-origin.
+</para>
+<para>
+<!-- .LP -->
+<function>XFillArc</function>
+and
+<function>XFillArcs</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadMatch</errorname>
+errors.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Font_Metrics">
+<title>Font Metrics</title>
+<!-- .XS -->
+<!-- (SN Font Metrics -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Font</primary></indexterm>
+A font is a graphical description of a set of characters that are used to
+increase efficiency whenever a set of small, similar sized patterns are
+repeatedly used.
+</para>
+<para>
+<!-- .LP -->
+This section discusses how to:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Load and free fonts
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Obtain and free font names
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Compute character string sizes
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Compute logical extents
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Query character string sizes
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The X server loads fonts whenever a program requests a new font.
+The server can cache fonts for quick lookup.
+Fonts are global across all screens in a server.
+Several levels are possible when dealing with fonts.
+Most applications simply use
+<function>XLoadQueryFont</function>
+to load a font and query the font metrics.
+</para>
+<para>
+<!-- .LP -->
+Characters in fonts are regarded as masks.
+Except for image text requests,
+the only pixels modified are those in which bits are set to 1 in the character.
+This means that it makes sense to draw text using stipples or tiles
+(for example, many menus gray-out unusable entries).
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+The
+<structname>XFontStruct</structname>
+structure contains all of the information for the font
+and consists of the font-specific information as well as
+a pointer to an array of
+<structname>XCharStruct</structname>
+structures for the
+characters contained in the font.
+The
+<structname>XFontStruct</structname>,
+<structname>XFontProp</structname>,
+and
+<structname>XCharStruct</structname>
+structures contain:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XCharStruct</primary></indexterm>
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+typedef struct {
+ short lbearing; /* origin to left edge of raster */
+ short rbearing; /* origin to right edge of raster */
+ short width; /* advance to next char's origin */
+ short ascent; /* baseline to top edge of raster */
+ short descent; /* baseline to bottom edge of raster */
+ unsigned short attributes; /* per char flags (not predefined) */
+} XCharStruct;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XFontProp</primary></indexterm>
+<literallayout class="monospaced">
+<!-- .TA .5i 1i 3i -->
+<!-- .ta .5i 1i 3i -->
+typedef struct {
+ Atom name;
+ unsigned long card32;
+} XFontProp;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XChar2b</primary></indexterm>
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+typedef struct { /* normal 16 bit characters are two bytes */
+ unsigned char byte1;
+ unsigned char byte2;
+} XChar2b;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XFontStruct</primary></indexterm>
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+typedef struct {
+ XExtData *ext_data; /* hook for extension to hang data */
+ Font fid; /* Font id for this font */
+ unsigned direction; /* hint about the direction font is painted */
+ unsigned min_char_or_byte2; /* first character */
+ unsigned max_char_or_byte2; /* last character */
+ unsigned min_byte1; /* first row that exists */
+ unsigned max_byte1; /* last row that exists */
+ Bool all_chars_exist; /* flag if all characters have nonzero size */
+ unsigned default_char; /* char to print for undefined character */
+ int n_properties; /* how many properties there are */
+ XFontProp *properties; /* pointer to array of additional properties */
+ XCharStruct min_bounds; /* minimum bounds over all existing char */
+ XCharStruct max_bounds; /* maximum bounds over all existing char */
+ XCharStruct *per_char; /* first_char to last_char information */
+ int ascent; /* logical extent above baseline for spacing */
+ int descent; /* logical descent below baseline for spacing */
+} XFontStruct;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+X supports single byte/character, two bytes/character matrix,
+and 16-bit character text operations.
+Note that any of these forms can be used with a font, but a
+single byte/character text request can only specify a single byte
+(that is, the first row of a 2-byte font).
+You should view 2-byte fonts as a two-dimensional matrix of defined
+characters: byte1 specifies the range of defined rows and
+byte2 defines the range of defined columns of the font.
+Single byte/character fonts have one row defined, and the byte2 range
+specified in the structure defines a range of characters.
+</para>
+<para>
+<!-- .LP -->
+The bounding box of a character is defined by the
+<structname>XCharStruct</structname>
+of that character.
+When characters are absent from a font,
+the default_char is used.
+When fonts have all characters of the same size,
+only the information in the
+<structname>XFontStruct</structname>
+min and max bounds are used.
+</para>
+<para>
+<!-- .LP -->
+The members of the
+<structname>XFontStruct</structname>
+have the following semantics:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The direction member can be either
+<symbol>FontLeftToRight</symbol>
+or
+<symbol>FontRightToLeft</symbol>.
+It is just a hint as to whether most
+<structname>XCharStruct</structname>
+elements
+have a positive
+(<symbol>FontLeftToRight</symbol>)
+or a negative
+(<symbol>FontRightToLeft</symbol>)
+character width
+metric.
+The core protocol defines no support for vertical text.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If the min_byte1 and max_byte1 members are both zero, min_char_or_byte2
+specifies the linear character index corresponding to the first element
+of the per_char array, and max_char_or_byte2 specifies the linear character
+index of the last element.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If either min_byte1 or max_byte1 are nonzero, both
+min_char_or_byte2 and max_char_or_byte2 are less than 256,
+and the 2-byte character index values corresponding to the
+per_char array element N (counting from 0) are:
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<!-- .nf -->
+ byte1 = N/D + min_byte1
+<!-- .br -->
+ byte2 = N\\D + min_char_or_byte2
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<!-- .fi -->
+where:
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<!-- .nf -->
+ D = max_char_or_byte2 - min_char_or_byte2 + 1
+ / = integer division
+ \\ = integer modulus
+<!-- .fi -->
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If the per_char pointer is NULL,
+all glyphs between the first and last character indexes
+inclusive have the same information,
+as given by both min_bounds and max_bounds.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If all_chars_exist is
+<symbol>True</symbol>,
+all characters in the per_char array have nonzero bounding boxes.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The default_char member specifies the character that will be used when an
+undefined or nonexistent character is printed.
+The default_char is a 16-bit character (not a 2-byte character).
+For a font using 2-byte matrix format,
+the default_char has byte1 in the most-significant byte
+and byte2 in the least significant byte.
+If the default_char itself specifies an undefined or nonexistent character,
+no printing is performed for an undefined or nonexistent character.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The min_bounds and max_bounds members contain the most extreme values of
+each individual
+<structname>XCharStruct</structname>
+component over all elements of this array
+(and ignore nonexistent characters).
+The bounding box of the font (the smallest
+rectangle enclosing the shape obtained by superimposing all of the
+characters at the same origin [x,y]) has its upper-left coordinate at:
+<literallayout class="monospaced">
+ [x + min_bounds.lbearing, y - max_bounds.ascent]
+</literallayout>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Its width is:
+<literallayout class="monospaced">
+ max_bounds.rbearing - min_bounds.lbearing
+</literallayout>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Its height is:
+<literallayout class="monospaced">
+ max_bounds.ascent + max_bounds.descent
+</literallayout>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The ascent member is the logical extent of the font above the baseline that is
+used for determining line spacing.
+Specific characters may extend beyond
+this.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The descent member is the logical extent of the font at or below the
+baseline that is used for determining line spacing.
+Specific characters may extend beyond this.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If the baseline is at Y-coordinate y,
+the logical extent of the font is inclusive between the Y-coordinate
+values (y - font.ascent) and (y + font.descent - 1).
+Typically,
+the minimum interline spacing between rows of text is given
+by ascent + descent.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+For a character origin at [x,y],
+the bounding box of a character (that is,
+the smallest rectangle that encloses the character's shape)
+described in terms of
+<structname>XCharStruct</structname>
+components is a rectangle with its upper-left corner at:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+[x + lbearing, y - ascent]
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+Its width is:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+rbearing - lbearing
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+Its height is:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+ascent + descent
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The origin for the next character is defined to be:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+[x + width, y]
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The lbearing member defines the extent of the left edge of the character ink
+from the origin.
+The rbearing member defines the extent of the right edge of the character ink
+from the origin.
+The ascent member defines the extent of the top edge of the character ink
+from the origin.
+The descent member defines the extent of the bottom edge of the character ink
+from the origin.
+The width member defines the logical width of the character.
+</para>
+<para>
+<!-- .LP -->
+Note that the baseline (the y position of the character origin)
+is logically viewed as being the scanline just below nondescending characters.
+When descent is zero,
+only pixels with Y-coordinates less than y are drawn,
+and the origin is logically viewed as being coincident with the left edge of
+a nonkerned character.
+When lbearing is zero,
+no pixels with X-coordinate less than x are drawn.
+Any of the
+<structname>XCharStruct</structname>
+metric members could be negative.
+If the width is negative,
+the next character will be placed to the left of the current origin.
+</para>
+<para>
+<!-- .LP -->
+The X protocol does not define the interpretation of the attributes member
+in the
+<structname>XCharStruct</structname>
+structure.
+A nonexistent character is represented with all members of its
+<structname>XCharStruct</structname>
+set to zero.
+</para>
+<para>
+<!-- .LP -->
+A font is not guaranteed to have any properties.
+The interpretation of the property value (for example, long or unsigned long)
+must be derived from <emphasis remap='I'>a priori</emphasis> knowledge of the property.
+A basic set of font properties is specified in the X Consortium standard
+<emphasis remap='I'>X Logical Font Description Conventions</emphasis>.
+</para>
+<sect2 id="Loading_and_Freeing_Fonts">
+<title>Loading and Freeing Fonts</title>
+<!-- .XS -->
+<!-- (SN Loading and Freeing Fonts -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to load fonts, get font information,
+unload fonts, and free font information.
+<indexterm><primary>Fonts</primary><secondary>getting information</secondary></indexterm>
+<indexterm><primary>Fonts</primary><secondary>unloading</secondary></indexterm>
+<indexterm><primary>Fonts</primary><secondary>freeing font information</secondary></indexterm>
+A few font functions use a
+<type>GContext</type>
+resource ID or a font ID interchangeably.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To load a given font, use
+<function>XLoadFont</function>.
+<indexterm significance="preferred"><primary>XLoadFont</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xloadfont'>
+<funcprototype>
+ <funcdef>Font <function>XLoadFont</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *name</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the name of the font,
+which is a null-terminated string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XLoadFont</function>
+function loads the specified font and returns its associated font ID.
+If the font name is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+Use of uppercase or lowercase does not matter.
+When the characters ``?'' and ``*'' are used in a font name, a
+pattern match is performed and any matching font is used.
+In the pattern,
+the ``?'' character will match any single character,
+and the ``*'' character will match any number of characters.
+A structured format for font names is specified in the X Consortium standard
+<emphasis remap='I'>X Logical Font Description Conventions</emphasis>.
+If
+<function>XLoadFont</function>
+was unsuccessful at loading the specified font,
+a
+<errorname>BadName</errorname>
+error results.
+Fonts are not associated with a particular screen
+and can be stored as a component
+of any GC.
+When the font is no longer needed, call
+<function>XUnloadFont</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XLoadFont</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadName</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To return information about an available font, use
+<function>XQueryFont</function>.
+<indexterm significance="preferred"><primary>XQueryFont</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xqueryfont'>
+<funcprototype>
+ <funcdef>XFontStruct *<function>XQueryFont</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XID<parameter> font_ID</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_ID</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font ID or the
+<type>GContext</type>
+ID.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XQueryFont</function>
+function returns a pointer to the
+<structname>XFontStruct</structname>
+structure, which contains information associated with the font.
+You can query a font or the font stored in a GC.
+The font ID stored in the
+<structname>XFontStruct</structname>
+structure will be the
+<type>GContext</type>
+ID, and you need to be careful when using this ID in other functions
+(see
+<function>XGContextFromGC</function>).
+If the font does not exist,
+<function>XQueryFont</function>
+returns NULL.
+To free this data, use
+<function>XFreeFontInfo</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To perform a
+<function>XLoadFont</function>
+and
+<function>XQueryFont</function>
+in a single operation, use
+<function>XLoadQueryFont</function>.
+<indexterm significance="preferred"><primary>XLoadQueryFont</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xloadqueryfont'>
+<funcprototype>
+ <funcdef>XFontStruct *<function>XLoadQueryFont</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *name</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the name of the font,
+which is a null-terminated string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XLoadQueryFont</function>
+function provides the most common way for accessing a font.
+<function>XLoadQueryFont</function>
+both opens (loads) the specified font and returns a pointer to the
+appropriate
+<structname>XFontStruct</structname>
+structure.
+If the font name is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+If the font does not exist,
+<function>XLoadQueryFont</function>
+returns NULL.
+</para>
+<para>
+<!-- .LP -->
+<function>XLoadQueryFont</function>
+can generate a
+<errorname>BadAlloc</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To unload the font and free the storage used by the font structure
+that was allocated by
+<function>XQueryFont</function>
+or
+<function>XLoadQueryFont</function>,
+use
+<function>XFreeFont</function>.
+<indexterm significance="preferred"><primary>XFreeFont</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfreefont'>
+<funcprototype>
+ <funcdef><function>XFreeFont</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XFontStruct<parameter> *font_struct</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_struct</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the storage associated with the font.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreeFont</function>
+function deletes the association between the font resource ID and the specified
+font and frees the
+<structname>XFontStruct</structname>
+structure.
+The font itself will be freed when no other resource references it.
+The data and the font should not be referenced again.
+</para>
+<para>
+<!-- .LP -->
+<function>XFreeFont</function>
+can generate a
+<errorname>BadFont</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To return a given font property, use
+<function>XGetFontProperty</function>.
+<indexterm significance="preferred"><primary>XGetFontProperty</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetfontproperty'>
+<funcprototype>
+ <funcdef>Bool <function>XGetFontProperty</function></funcdef>
+ <paramdef>XFontStruct<parameter> *font_struct</parameter></paramdef>
+ <paramdef>Atom<parameter> atom</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> *value_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_struct</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the storage associated with the font.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>atom</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the atom for the property name you want returned.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the value of the font property.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Given the atom for that property,
+the
+<function>XGetFontProperty</function>
+function returns the value of the specified font property.
+<function>XGetFontProperty</function>
+also returns
+<symbol>False</symbol>
+if the property was not defined or
+<symbol>True</symbol>
+if it was defined.
+A set of predefined atoms exists for font properties,
+which can be found in
+<filename class="headerfile">&lt;X11/Xatom.h&gt;</filename>.
+<indexterm type="file"><primary><filename class="headerfile">X11/Xatom.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xatom.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xatom.h&gt;</filename></secondary></indexterm>
+This set contains the standard properties associated with
+a font.
+Although it is not guaranteed,
+it is likely that the predefined font properties will be present.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To unload a font that was loaded by
+<function>XLoadFont</function>,
+use
+<function>XUnloadFont</function>.
+<indexterm significance="preferred"><primary>XUnloadFont</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xunloadfont'>
+<funcprototype>
+ <funcdef><function>XUnloadFont</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Font<parameter> font</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUnloadFont</function>
+function deletes the association between the font resource ID and the specified font.
+The font itself will be freed when no other resource references it.
+The font should not be referenced again.
+</para>
+<para>
+<!-- .LP -->
+<function>XUnloadFont</function>
+can generate a
+<errorname>BadFont</errorname>
+error.
+</para>
+</sect2>
+<sect2 id="Obtaining_and_Freeing_Font_Names_and_Information">
+<title>Obtaining and Freeing Font Names and Information</title>
+<!-- .XS -->
+<!-- (SN Obtaining and Freeing Font Names and Information -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+You obtain font names and information by matching a wildcard specification
+when querying a font type for a list of available sizes and so on.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To return a list of the available font names, use
+<function>XListFonts</function>.
+<indexterm significance="preferred"><primary>XListFonts</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xlistfonts'>
+<funcprototype>
+ <funcdef>char **<function>XListFonts</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *pattern</parameter></paramdef>
+ <paramdef>int<parameter> maxnames</parameter></paramdef>
+ <paramdef>int<parameter> *actual_count_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pattern</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the null-terminated pattern string that can contain wildcard
+characters.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>maxnames</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the maximum number of names to be returned.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>actual_count_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the actual number of font names.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XListFonts</function>
+function returns an array of available font names
+(as controlled by the font search path; see
+<function>XSetFontPath</function>)
+that match the string you passed to the pattern argument.
+The pattern string can contain any characters,
+but each asterisk (*) is a wildcard for any number of characters,
+and each question mark (?) is a wildcard for a single character.
+If the pattern string is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+Use of uppercase or lowercase does not matter.
+Each returned string is null-terminated.
+If the data returned by the server is in the Latin Portable Character Encoding,
+then the returned strings are in the Host Portable Character Encoding.
+Otherwise, the result is implementation-dependent.
+If there are no matching font names,
+<function>XListFonts</function>
+returns NULL.
+The client should call
+<function>XFreeFontNames</function>
+when finished with the result to free the memory.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To free a font name array, use
+<function>XFreeFontNames</function>.
+<indexterm significance="preferred"><primary>XFreeFontNames</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfreefontnames'>
+<funcprototype>
+ <funcdef><function>XFreeFontNames</function></funcdef>
+ <paramdef>char<parameter> *list[]</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the array of strings you want to free.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreeFontNames</function>
+function frees the array and strings returned by
+<function>XListFonts</function>
+or
+<function>XListFontsWithInfo</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the names and information about available fonts, use
+<function>XListFontsWithInfo</function>.
+<indexterm significance="preferred"><primary>XListFontsWithInfo</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xlistfontswithinfo'>
+<funcprototype>
+ <funcdef>char **<function>XListFontsWithInfo</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *pattern</parameter></paramdef>
+ <paramdef>int<parameter> maxnames</parameter></paramdef>
+ <paramdef>int<parameter> *count_return</parameter></paramdef>
+ <paramdef>XFontStruct<parameter> **info_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pattern</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the null-terminated pattern string that can contain wildcard
+characters.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>maxnames</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the maximum number of names to be returned.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the actual number of matched font names.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>info_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the font information.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XListFontsWithInfo</function>
+function returns a list of font names that match the specified pattern and their
+associated font information.
+The list of names is limited to size specified by maxnames.
+The information returned for each font is identical to what
+<function>XLoadQueryFont</function>
+would return except that the per-character metrics are not returned.
+The pattern string can contain any characters,
+but each asterisk (*) is a wildcard for any number of characters,
+and each question mark (?) is a wildcard for a single character.
+If the pattern string is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+Use of uppercase or lowercase does not matter.
+Each returned string is null-terminated.
+If the data returned by the server is in the Latin Portable Character Encoding,
+then the returned strings are in the Host Portable Character Encoding.
+Otherwise, the result is implementation-dependent.
+If there are no matching font names,
+<function>XListFontsWithInfo</function>
+returns NULL.
+</para>
+<para>
+<!-- .LP -->
+To free only the allocated name array,
+the client should call
+<function>XFreeFontNames</function>.
+To free both the name array and the font information array
+or to free just the font information array,
+the client should call
+<function>XFreeFontInfo</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To free font structures and font names, use
+<function>XFreeFontInfo</function>.
+<indexterm significance="preferred"><primary>XFreeFontInfo</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfreefontinfo'>
+<funcprototype>
+ <funcdef><function>XFreeFontInfo</function></funcdef>
+ <paramdef>char<parameter> **names</parameter></paramdef>
+ <paramdef>XFontStruct<parameter> *free_info</parameter></paramdef>
+ <paramdef>int<parameter> actual_count</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>names</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the list of font names.
+
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>free_info</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font information.
+
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>actual_count</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the actual number of font names.
+
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreeFontInfo</function>
+function frees a font structure or an array of font structures
+and optionally an array of font names.
+If NULL is passed for names, no font names are freed.
+If a font structure for an open font (returned by
+<function>XLoadQueryFont</function>)
+is passed, the structure is freed,
+but the font is not closed; use
+<function>XUnloadFont</function>
+to close the font.
+</para>
+</sect2>
+<sect2 id="Computing_Character_String_Sizes">
+<title>Computing Character String Sizes</title>
+<!-- .XS -->
+<!-- (SN Computing Character String Sizes -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to compute the width,
+the logical extents,
+and the server information about 8-bit and 2-byte text strings.
+<indexterm><primary>XTextWidth</primary></indexterm>
+<indexterm><primary>XTextWidth16</primary></indexterm>
+The width is computed by adding the character widths of all the characters.
+It does not matter if the font is an 8-bit or 2-byte font.
+These functions return the sum of the character metrics in pixels.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To determine the width of an 8-bit character string, use
+<function>XTextWidth</function>.
+<indexterm significance="preferred"><primary>XTextWidth</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xtextwidth'>
+<funcprototype>
+ <funcdef>int <function>XTextWidth</function></funcdef>
+ <paramdef>XFontStruct<parameter> *font_struct</parameter></paramdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> count</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_struct</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font used for the width computation.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character count in the specified string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To determine the width of a 2-byte character string, use
+<function>XTextWidth16</function>.
+<indexterm significance="preferred"><primary>XTextWidth16</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xtextwidth16'>
+<funcprototype>
+ <funcdef>int <function>XTextWidth16</function></funcdef>
+ <paramdef>XFontStruct<parameter> *font_struct</parameter></paramdef>
+ <paramdef>XChar2b<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> count</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_struct</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font used for the width computation.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character count in the specified string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+</para>
+</sect2>
+<sect2 id="Computing_Logical_Extents">
+<title>Computing Logical Extents</title>
+<!-- .XS -->
+<!-- (SN Computing Logical Extents -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To compute the bounding box of an 8-bit character string in a given font, use
+<function>XTextExtents</function>.
+<indexterm significance="preferred"><primary>XTextExtents</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xtextextents'>
+<funcprototype>
+ <funcdef><function>XTextExtents</function></funcdef>
+ <paramdef>XFontStruct<parameter> *font_struct</parameter></paramdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> nchars</parameter></paramdef>
+ <paramdef>int<parameter> *direction_return</parameter></paramdef>
+ <paramdef>int*font_ascent_return,<parameter> *font_descent_return</parameter></paramdef>
+ <paramdef>XCharStruct<parameter> *overall_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_struct</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XFontStruct</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nchars</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>direction_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the value of the direction hint
+(<symbol>FontLeftToRight</symbol>
+or
+<symbol>FontRightToLeft</symbol>).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_ascent_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the font ascent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_descent_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the font descent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>overall_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the overall size in the specified
+<structname>XCharStruct</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To compute the bounding box of a 2-byte character string in a given font, use
+<function>XTextExtents16</function>.
+<indexterm significance="preferred"><primary>XTextExtents16</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xtextextents16'>
+<funcprototype>
+ <funcdef><function>XTextExtents16</function></funcdef>
+ <paramdef>XFontStruct<parameter> *font_struct</parameter></paramdef>
+ <paramdef>XChar2b<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> nchars</parameter></paramdef>
+ <paramdef>int<parameter> *direction_return</parameter></paramdef>
+ <paramdef>int*font_ascent_return,<parameter> *font_descent_return</parameter></paramdef>
+ <paramdef>XCharStruct<parameter> *overall_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_struct</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XFontStruct</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nchars</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>direction_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the value of the direction hint
+(<symbol>FontLeftToRight</symbol>
+or
+<symbol>FontRightToLeft</symbol>).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_ascent_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the font ascent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_descent_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the font descent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>overall_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the overall size in the specified
+<structname>XCharStruct</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XTextExtents</function>
+and
+<function>XTextExtents16</function>
+functions
+perform the size computation locally and, thereby,
+avoid the round-trip overhead of
+<function>XQueryTextExtents</function>
+and
+<function>XQueryTextExtents16</function>.
+Both functions return an
+<structname>XCharStruct</structname>
+structure, whose members are set to the values as follows.
+</para>
+<para>
+<!-- .LP -->
+The ascent member is set to the maximum of the ascent metrics of all
+characters in the string.
+The descent member is set to the maximum of the descent metrics.
+The width member is set to the sum of the character-width metrics of all
+characters in the string.
+For each character in the string,
+let W be the sum of the character-width metrics of all characters preceding
+it in the string.
+Let L be the left-side-bearing metric of the character plus W.
+Let R be the right-side-bearing metric of the character plus W.
+The lbearing member is set to the minimum L of all characters in the string.
+The rbearing member is set to the maximum R.
+</para>
+<para>
+<!-- .LP -->
+For fonts defined with linear indexing rather than 2-byte matrix indexing,
+each
+<structname>XChar2b</structname>
+structure is interpreted as a 16-bit number with byte1 as the
+most significant byte.
+If the font has no defined default character,
+undefined characters in the string are taken to have all zero metrics.
+</para>
+</sect2>
+<sect2 id="Querying_Character_String_Sizes">
+<title>Querying Character String Sizes</title>
+<!-- .XS -->
+<!-- (SN Querying Character String Sizes -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To query the server for the bounding box of an 8-bit character string in a
+given font, use
+<function>XQueryTextExtents</function>.
+<indexterm significance="preferred"><primary>XQueryTextExtents</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xquerytextextents'>
+<funcprototype>
+ <funcdef><function>XQueryTextExtents</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XID<parameter> font_ID</parameter></paramdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> nchars</parameter></paramdef>
+ <paramdef>int<parameter> *direction_return</parameter></paramdef>
+ <paramdef>int*font_ascent_return,<parameter> *font_descent_return</parameter></paramdef>
+ <paramdef>XCharStruct<parameter> *overall_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_ID</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies either the font ID or the
+<type>GContext</type>
+ID that contains the font.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nchars</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>direction_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the value of the direction hint
+(<symbol>FontLeftToRight</symbol>
+or
+<symbol>FontRightToLeft</symbol>).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_ascent_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the font ascent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_descent_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the font descent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>overall_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the overall size in the specified
+<structname>XCharStruct</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To query the server for the bounding box of a 2-byte character string
+in a given font, use
+<function>XQueryTextExtents16</function>.
+<indexterm significance="preferred"><primary>XQueryTextExtents16</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xquerytextextents16'>
+<funcprototype>
+ <funcdef><function>XQueryTextExtents16</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XID<parameter> font_ID</parameter></paramdef>
+ <paramdef>XChar2b<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> nchars</parameter></paramdef>
+ <paramdef>int<parameter> *direction_return</parameter></paramdef>
+ <paramdef>int*font_ascent_return,<parameter> *font_descent_return</parameter></paramdef>
+ <paramdef>XCharStruct<parameter> *overall_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_ID</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies either the font ID or the
+<type>GContext</type>
+ID that contains the font.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nchars</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>direction_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the value of the direction hint
+(<symbol>FontLeftToRight</symbol>
+or
+<symbol>FontRightToLeft</symbol>).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_ascent_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the font ascent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_descent_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the font descent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>overall_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the overall size in the specified
+<structname>XCharStruct</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XQueryTextExtents</function>
+and
+<function>XQueryTextExtents16</function>
+functions return the bounding box of the specified 8-bit and 16-bit
+character string in the specified font or the font contained in the
+specified GC.
+These functions query the X server and, therefore, suffer the round-trip
+overhead that is avoided by
+<function>XTextExtents</function>
+and
+<function>XTextExtents16</function>.
+Both functions return a
+<structname>XCharStruct</structname>
+structure, whose members are set to the values as follows.
+</para>
+<para>
+<!-- .LP -->
+The ascent member is set to the maximum of the ascent metrics
+of all characters in the string.
+The descent member is set to the maximum of the descent metrics.
+The width member is set to the sum of the character-width metrics
+of all characters in the string.
+For each character in the string,
+let W be the sum of the character-width metrics of all characters preceding
+it in the string.
+Let L be the left-side-bearing metric of the character plus W.
+Let R be the right-side-bearing metric of the character plus W.
+The lbearing member is set to the minimum L of all characters in the string.
+The rbearing member is set to the maximum R.
+</para>
+<para>
+<!-- .LP -->
+For fonts defined with linear indexing rather than 2-byte matrix indexing,
+each
+<structname>XChar2b</structname>
+structure is interpreted as a 16-bit number with byte1 as the
+most significant byte.
+If the font has no defined default character,
+undefined characters in the string are taken to have all zero metrics.
+</para>
+<para>
+<!-- .LP -->
+Characters with all zero metrics are ignored.
+If the font has no defined default_char,
+the undefined characters in the string are also ignored.
+</para>
+<para>
+<!-- .LP -->
+<function>XQueryTextExtents</function>
+and
+<function>XQueryTextExtents16</function>
+can generate
+<errorname>BadFont</errorname>
+and
+<errorname>BadGC</errorname>
+errors.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Drawing_Text">
+<title>Drawing Text</title>
+<!-- .XS -->
+<!-- (SN Drawing Text -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This section discusses how to draw:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Complex text
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Text characters
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Image text characters
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The fundamental text functions
+<function>XDrawText</function>
+and
+<function>XDrawText16</function>
+use the following structures:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XTextItem</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+typedef struct {
+ char *chars; /* pointer to string */
+ int nchars; /* number of characters */
+ int delta; /* delta between strings */
+ Font font; /* Font to print it in, None don't change */
+} XTextItem;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XTextItem16</primary></indexterm>
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+typedef struct {
+ XChar2b *chars; /* pointer to two-byte characters */
+ int nchars; /* number of characters */
+ int delta; /* delta between strings */
+ Font font; /* font to print it in, None don't change */
+} XTextItem16;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If the font member is not
+<symbol>None</symbol>,
+the font is changed before printing and also is stored in the GC.
+If an error was generated during text drawing,
+the previous items may have been drawn.
+The baseline of the characters are drawn starting at the x and y
+coordinates that you pass in the text drawing functions.
+</para>
+<para>
+<!-- .LP -->
+For example, consider the background rectangle drawn by
+<function>XDrawImageString</function>.
+If you want the upper-left corner of the background rectangle
+to be at pixel coordinate (x,y), pass the (x,y + ascent)
+as the baseline origin coordinates to the text functions.
+The ascent is the font ascent, as given in the
+<structname>XFontStruct</structname>
+structure.
+If you want the lower-left corner of the background rectangle
+to be at pixel coordinate (x,y), pass the (x,y - descent + 1)
+as the baseline origin coordinates to the text functions.
+The descent is the font descent, as given in the
+<structname>XFontStruct</structname>
+structure.
+</para>
+<sect2 id="Drawing_Complex_Text">
+<title>Drawing Complex Text</title>
+<!-- .XS -->
+<!-- (SN Drawing Complex Text -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Text</primary><secondary>drawing</secondary></indexterm>
+<indexterm><primary>Drawing</primary><secondary>text items</secondary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+To draw 8-bit characters in a given drawable, use
+<function>XDrawText</function>.
+<indexterm significance="preferred"><primary>XDrawText</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawtext'>
+<funcprototype>
+ <funcdef><function>XDrawText</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>XTextItem<parameter> *items</parameter></paramdef>
+ <paramdef>int<parameter> nitems</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy , which are relative to the origin of the specified drawable \ -->
+and define the origin of the first character
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>items</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of text items.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nitems</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of text items in the array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To draw 2-byte characters in a given drawable, use
+<function>XDrawText16</function>.
+<indexterm significance="preferred"><primary>XDrawText16</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawtext16'>
+<funcprototype>
+ <funcdef><function>XDrawText16</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>XTextItem16<parameter> *items</parameter></paramdef>
+ <paramdef>int<parameter> nitems</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy , which are relative to the origin of the specified drawable \ -->
+and define the origin of the first character
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>items</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of text items.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nitems</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of text items in the array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDrawText16</function>
+function is similar to
+<function>XDrawText</function>
+except that it uses 2-byte or 16-bit characters.
+Both functions allow complex spacing and font shifts between counted strings.
+</para>
+<para>
+<!-- .LP -->
+Each text item is processed in turn.
+A font member other than
+<symbol>None</symbol>
+in an item causes the font to be stored in the GC
+and used for subsequent text.
+A text element delta specifies an additional change
+in the position along the x axis before the string is drawn.
+The delta is always added to the character origin
+and is not dependent on any characteristics of the font.
+Each character image, as defined by the font in the GC, is treated as an
+additional mask for a fill operation on the drawable.
+The drawable is modified only where the font character has a bit set to 1.
+If a text item generates a
+<errorname>BadFont</errorname>
+error, the previous text items may have been drawn.
+</para>
+<para>
+<!-- .LP -->
+For fonts defined with linear indexing rather than 2-byte matrix indexing,
+each
+<structname>XChar2b</structname>
+structure is interpreted as a 16-bit number with byte1 as the
+most significant byte.
+</para>
+<para>
+<!-- .LP -->
+Both functions use these GC components:
+function, plane-mask, fill-style, font, subwindow-mode,
+clip-x-origin, clip-y-origin, and clip-mask.
+They also use these GC mode-dependent components:
+foreground, background, tile, stipple, tile-stipple-x-origin,
+and tile-stipple-y-origin.
+</para>
+<para>
+<!-- .LP -->
+<function>XDrawText</function>
+and
+<function>XDrawText16</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadFont</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadMatch</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Drawing_Text_Characters">
+<title>Drawing Text Characters</title>
+<!-- .XS -->
+<!-- (SN Drawing Text Characters -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Strings</primary><secondary>drawing</secondary></indexterm>
+<indexterm><primary>Drawing</primary><secondary>strings</secondary></indexterm>
+To draw 8-bit characters in a given drawable, use
+<function>XDrawString</function>.
+<indexterm significance="preferred"><primary>XDrawString</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawstring'>
+<funcprototype>
+ <funcdef><function>XDrawString</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> length</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy , which are relative to the origin of the specified drawable \ -->
+and define the origin of the first character
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>length</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To draw 2-byte characters in a given drawable, use
+<function>XDrawString16</function>.
+<indexterm significance="preferred"><primary>XDrawString16</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawstring16'>
+<funcprototype>
+ <funcdef><function>XDrawString16</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>XChar2b<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> length</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy , which are relative to the origin of the specified drawable \ -->
+and define the origin of the first character
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>length</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Each character image, as defined by the font in the GC, is treated as an
+additional mask for a fill operation on the drawable.
+The drawable is modified only where the font character has a bit set to 1.
+For fonts defined with 2-byte matrix indexing
+and used with
+<function>XDrawString16</function>,
+each byte is used as a byte2 with a byte1 of zero.
+</para>
+<para>
+<!-- .LP -->
+Both functions use these GC components:
+function, plane-mask, fill-style, font, subwindow-mode, clip-x-origin,
+clip-y-origin, and clip-mask.
+They also use these GC mode-dependent components:
+foreground, background, tile, stipple, tile-stipple-x-origin,
+and tile-stipple-y-origin.
+</para>
+<para>
+<!-- .LP -->
+<function>XDrawString</function>
+and
+<function>XDrawString16</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadMatch</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Drawing_Image_Text_Characters">
+<title>Drawing Image Text Characters</title>
+<!-- .XS -->
+<!-- (SN Drawing Image Text Characters -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Image text</primary><secondary>drawing</secondary></indexterm>
+<indexterm><primary>Drawing</primary><secondary>image text</secondary></indexterm>
+Some applications, in particular terminal emulators, need to
+print image text in which both the foreground and background bits of
+each character are painted.
+This prevents annoying flicker on many displays.
+<indexterm><primary>XDrawImageString</primary></indexterm>
+<indexterm><primary>XDrawImageString16</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To draw 8-bit image text characters in a given drawable, use
+<function>XDrawImageString</function>.
+<indexterm significance="preferred"><primary>XDrawImageString</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawimagestring'>
+<funcprototype>
+ <funcdef><function>XDrawImageString</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> length</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy , which are relative to the origin of the specified drawable \ -->
+and define the origin of the first character
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>length</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To draw 2-byte image text characters in a given drawable, use
+<function>XDrawImageString16</function>.
+<indexterm significance="preferred"><primary>XDrawImageString16</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdrawimagestring16'>
+<funcprototype>
+ <funcdef><function>XDrawImageString16</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>XChar2b<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> length</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy , which are relative to the origin of the specified drawable \ -->
+and define the origin of the first character
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>length</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDrawImageString16</function>
+function is similar to
+<function>XDrawImageString</function>
+except that it uses 2-byte or 16-bit characters.
+Both functions also use both the foreground and background pixels
+of the GC in the destination.
+</para>
+<para>
+<!-- .LP -->
+The effect is first to fill a
+destination rectangle with the background pixel defined in the GC and then
+to paint the text with the foreground pixel.
+The upper-left corner of the filled rectangle is at:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+[x, y - font-ascent]
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The width is:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+overall-width
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The height is:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+font-ascent + font-descent
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The overall-width, font-ascent, and font-descent
+are as would be returned by
+<function>XQueryTextExtents</function>
+using gc and string.
+The function and fill-style defined in the GC are ignored for these functions.
+The effective function is
+<symbol>GXcopy</symbol>,
+and the effective fill-style is
+<symbol>FillSolid</symbol>.
+</para>
+<para>
+<!-- .LP -->
+For fonts defined with 2-byte matrix indexing
+and used with
+<function>XDrawImageString</function>,
+each byte is used as a byte2 with a byte1 of zero.
+</para>
+<para>
+<!-- .LP -->
+Both functions use these GC components:
+plane-mask, foreground, background, font, subwindow-mode, clip-x-origin,
+clip-y-origin, and clip-mask.
+</para>
+<para>
+<!-- .LP -->
+<function>XDrawImageString</function>
+and
+<function>XDrawImageString16</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadMatch</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect2>
+</sect1>
+<sect1 id="Transferring_Images_between_Client_and_Server">
+<title>Transferring Images between Client and Server</title>
+<!-- .XS -->
+<!-- (SN Transferring Images between Client and Server -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to transfer images between a client
+and the server.
+Because the server may require diverse data formats,
+Xlib provides an image object that fully describes the data in memory
+and that provides for basic operations on that data.
+You should reference the data
+through the image object rather than referencing the data directly.
+However, some implementations of the Xlib library may efficiently deal with
+frequently used data formats by replacing
+functions in the procedure vector with special case functions.
+Supported operations include destroying the image, getting a pixel,
+storing a pixel, extracting a subimage of an image, and adding a constant
+to an image (see section 16.8).
+</para>
+<para>
+<!-- .LP -->
+All the image manipulation functions discussed in this section make use of
+the
+<structname>XImage</structname>
+structure,
+which describes an image as it exists in the client's memory.
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XImage</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 1i 3i -->
+<!-- .ta .5i 1i 3i -->
+typedef struct _XImage {
+ int width, height; /* size of image */
+ int xoffset; /* number of pixels offset in X direction */
+ int format; /* XYBitmap, XYPixmap, ZPixmap */
+ char *data; /* pointer to image data */
+ int byte_order; /* data byte order, LSBFirst, MSBFirst */
+ int bitmap_unit; /* quant. of scanline 8, 16, 32 */
+ int bitmap_bit_order; /* LSBFirst, MSBFirst */
+ int bitmap_pad; /* 8, 16, 32 either XY or ZPixmap */
+ int depth; /* depth of image */
+ int bytes_per_line; /* accelerator to next scanline */
+ int bits_per_pixel; /* bits per pixel (ZPixmap) */
+ unsigned long red_mask; /* bits in z arrangement */
+ unsigned long green_mask;
+ unsigned long blue_mask;
+ XPointer obdata; /* hook for the object routines to hang on */
+ struct funcs { /* image manipulation routines */
+ struct _XImage *(*create_image)();
+ int (*destroy_image)();
+ unsigned long (*get_pixel)();
+ int (*put_pixel)();
+ struct _XImage *(*sub_image)();
+ int (*add_pixel)();
+ } f;
+} XImage;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To initialize the image manipulation routines of an image structure, use
+<function>XInitImage</function>.
+<indexterm significance="preferred"><primary>XInitImage</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xinitimage'>
+<funcprototype>
+ <funcdef>Status <function>XInitImage</function></funcdef>
+ <paramdef>XImage<parameter> *image</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ximage</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the image.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XInitImage</function>
+function initializes the internal image manipulation routines of an
+image structure, based on the values of the various structure members.
+All fields other than the manipulation routines must already be initialized.
+If the bytes_per_line member is zero,
+<function>XInitImage</function>
+will assume the image data is contiguous in memory and set the
+bytes_per_line member to an appropriate value based on the other
+members; otherwise, the value of bytes_per_line is not changed.
+All of the manipulation routines are initialized to functions
+that other Xlib image manipulation functions need to operate on the
+type of image specified by the rest of the structure.
+</para>
+<para>
+<!-- .LP -->
+This function must be called for any image constructed by the client
+before passing it to any other Xlib function.
+Image structures created or returned by Xlib do not need to be
+initialized in this fashion.
+</para>
+<para>
+<!-- .LP -->
+This function returns a nonzero status if initialization of the
+structure is successful. It returns zero if it detected some error
+or inconsistency in the structure, in which case the image is not changed.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To combine an image with a rectangle of a drawable on the display,
+use
+<function>XPutImage</function>.
+<indexterm significance="preferred"><primary>XPutImage</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xputimage'>
+<funcprototype>
+ <funcdef><function>XPutImage</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>XImage<parameter> *image</parameter></paramdef>
+ <paramdef>intsrc_x,<parameter> src_y</parameter></paramdef>
+ <paramdef>intdest_x,<parameter> dest_y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>image</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the image you want combined with the rectangle.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src_x</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the offset in X from the left edge of the image defined
+by the
+<structname>XImage</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src_y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the offset in Y from the top edge of the image defined
+by the
+<structname>XImage</structname>
+structure.
+<!-- .ds Dx , which are relative to the origin of the drawable \ -->
+and are the coordinates of the subimage
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Dx.
+<!-- .ds Wh \ of the subimage, which define the dimensions of the rectangle -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XPutImage</function>
+function
+combines an image with a rectangle of the specified drawable.
+The section of the image defined by the src_x, src_y, width, and height
+arguments is drawn on the specified part of the drawable.
+If
+<symbol>XYBitmap</symbol>
+format is used, the depth of the image must be one,
+or a
+<errorname>BadMatch</errorname>
+error results.
+The foreground pixel in the GC defines the source for the one bits in the image,
+and the background pixel defines the source for the zero bits.
+For
+<symbol>XYPixmap</symbol>
+and
+<symbol>ZPixmap</symbol>,
+the depth of the image must match the depth of the drawable,
+or a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+If the characteristics of the image (for example, byte_order and bitmap_unit)
+differ from what the server requires,
+<function>XPutImage</function>
+automatically makes the appropriate
+conversions.
+</para>
+<para>
+<!-- .LP -->
+This function uses these GC components:
+function, plane-mask, subwindow-mode, clip-x-origin, clip-y-origin,
+and clip-mask.
+It also uses these GC mode-dependent components:
+foreground and background.
+</para>
+<para>
+<!-- .LP -->
+<function>XPutImage</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+<errorname>BadMatch</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To return the contents of a rectangle in a given drawable on the display,
+use
+<function>XGetImage</function>.
+This function specifically supports rudimentary screen dumps.
+<indexterm significance="preferred"><primary>XGetImage</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetimage'>
+<funcprototype>
+ <funcdef>XImage *<function>XGetImage</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> plane_mask</parameter></paramdef>
+ <paramdef>int<parameter> format</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+<!-- .ds Xy , which are relative to the origin of the drawable \ -->
+and define the upper-left corner of the rectangle
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+<!-- .ds Wh \ of the subimage, which define the dimensions of the rectangle -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>plane_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the plane mask.
+<!-- .\" *** JIM: NEED MORE INFO FOR THIS. *** -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the format for the image.
+You can pass
+<symbol>XYPixmap</symbol>
+or
+<symbol>ZPixmap</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetImage</function>
+function returns a pointer to an
+<structname>XImage</structname>
+structure.
+This structure provides you with the contents of the specified rectangle of
+the drawable in the format you specify.
+If the format argument is
+<symbol>XYPixmap</symbol>,
+the image contains only the bit planes you passed to the plane_mask argument.
+If the plane_mask argument only requests a subset of the planes of the
+display, the depth of the returned image will be the number of planes
+requested.
+If the format argument is
+<symbol>ZPixmap</symbol>,
+<function>XGetImage</function>
+returns as zero the bits in all planes not
+specified in the plane_mask argument.
+The function performs no range checking on the values in plane_mask and ignores
+extraneous bits.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetImage</function>
+returns the depth of the image to the depth member of the
+<structname>XImage</structname>
+structure.
+The depth of the image is as specified when the drawable was created,
+except when getting a subset of the planes in
+<symbol>XYPixmap</symbol>
+format, when the depth is given by the number of bits set to 1 in plane_mask.
+</para>
+<para>
+<!-- .LP -->
+If the drawable is a pixmap,
+the given rectangle must be wholly contained within the pixmap,
+or a
+<errorname>BadMatch</errorname>
+error results.
+If the drawable is a window,
+the window must be viewable,
+and it must be the case that if there were no inferiors or overlapping windows,
+the specified rectangle of the window would be fully visible on the screen
+and wholly contained within the outside edges of the window,
+or a
+<errorname>BadMatch</errorname>
+error results.
+Note that the borders of the window can be included and read with
+this request.
+If the window has backing-store, the backing-store contents are
+returned for regions of the window that are obscured by noninferior
+windows.
+If the window does not have backing-store,
+the returned contents of such obscured regions are undefined.
+The returned contents of visible regions of inferiors
+of a different depth than the specified window's depth are also undefined.
+The pointer cursor image is not included in the returned contents.
+If a problem occurs,
+<function>XGetImage</function>
+returns NULL.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetImage</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadMatch</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To copy the contents of a rectangle on the display
+to a location within a preexisting image structure, use
+<function>XGetSubImage</function>.
+<indexterm significance="preferred"><primary>XGetSubImage</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetsubimage'>
+<funcprototype>
+ <funcdef>XImage *<function>XGetSubImage</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> plane_mask</parameter></paramdef>
+ <paramdef>int<parameter> format</parameter></paramdef>
+ <paramdef>XImage<parameter> *dest_image</parameter></paramdef>
+ <paramdef>intdest_x,<parameter> dest_y</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+<!-- .ds Xy , which are relative to the origin of the drawable \ -->
+and define the upper-left corner of the rectangle
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+<!-- .ds Wh \ of the subimage, which define the dimensions of the rectangle -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>plane_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the plane mask.
+<!-- .\" *** JIM: NEED MORE INFO FOR THIS. *** -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the format for the image.
+You can pass
+<symbol>XYPixmap</symbol>
+or
+<symbol>ZPixmap</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_image</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the destination image.
+<!-- .ds Dx , which are relative to the origin of the destination rectangle, \ -->
+specify its upper-left corner, and determine where the subimage \
+is placed in the destination image
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Dx.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetSubImage</function>
+function updates dest_image with the specified subimage in the same manner as
+<function>XGetImage</function>.
+If the format argument is
+<symbol>XYPixmap</symbol>,
+the image contains only the bit planes you passed to the plane_mask argument.
+If the format argument is
+<symbol>ZPixmap</symbol>,
+<function>XGetSubImage</function>
+returns as zero the bits in all planes not
+specified in the plane_mask argument.
+The function performs no range checking on the values in plane_mask and ignores
+extraneous bits.
+As a convenience,
+<function>XGetSubImage</function>
+returns a pointer to the same
+<structname>XImage</structname>
+structure specified by dest_image.
+</para>
+<para>
+<!-- .LP -->
+The depth of the destination
+<structname>XImage</structname>
+structure must be the same as that of the drawable.
+If the specified subimage does not fit at the specified location
+on the destination image, the right and bottom edges are clipped.
+If the drawable is a pixmap,
+the given rectangle must be wholly contained within the pixmap,
+or a
+<errorname>BadMatch</errorname>
+error results.
+If the drawable is a window,
+the window must be viewable,
+and it must be the case that if there were no inferiors or overlapping windows,
+the specified rectangle of the window would be fully visible on the screen
+and wholly contained within the outside edges of the window,
+or a
+<errorname>BadMatch</errorname>
+error results.
+If the window has backing-store,
+then the backing-store contents are returned for regions of the window
+that are obscured by noninferior windows.
+If the window does not have backing-store,
+the returned contents of such obscured regions are undefined.
+The returned contents of visible regions of inferiors
+of a different depth than the specified window's depth are also undefined.
+If a problem occurs,
+<function>XGetSubImage</function>
+returns NULL.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetSubImage</function>
+can generate
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+<errorname>BadMatch</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+<!-- .bp -->
+
+
+</para>
+</sect1>
+</chapter>
diff --git a/libX11/specs/libX11/CH09.xml b/libX11/specs/libX11/CH09.xml
index 7d0f779f1..eff97c39c 100644
--- a/libX11/specs/libX11/CH09.xml
+++ b/libX11/specs/libX11/CH09.xml
@@ -1,2016 +1,2016 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<chapter id="window_and_session_manager_functions">
-<title>Window and Session Manager Functions</title>
-
-<para>
-Although it is difficult to categorize functions as exclusively for an application,
-a window manager, or a session manager, the functions in this chapter are most
-often used by window managers and session managers. It is not expected that
-these functions will be used by most application programs. Xlib provides
-management functions to:
-</para>
-
-<itemizedlist>
- <listitem><para>Change the parent of a window</para></listitem>
- <listitem><para>Control the lifetime of a window</para></listitem>
- <listitem><para>Manage installed colormaps</para></listitem>
- <listitem><para>Set and retrieve the font search path</para></listitem>
- <listitem><para>Grab the server</para></listitem>
- <listitem><para>Kill a client</para></listitem>
- <listitem><para>Control the screen saver</para></listitem>
- <listitem><para>Control host access</para></listitem>
-</itemizedlist>
-
-<sect1 id="Changing_the_Parent_of_a_Window">
-<title>Changing the Parent of a Window</title>
-<!-- .XS -->
-<!-- (SN Changing the Parent of a Window -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To change a window's parent to another window on the same screen, use
-<function>XReparentWindow</function>.
-There is no way to move a window between screens.
-<indexterm significance="preferred"><primary>XReparentWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XReparentWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Window<parameter> parent</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>parent</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the parent window.
-<!-- .ds Xy \ of the position in the new parent window -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If the specified window is mapped,
-<function>XReparentWindow</function>
-automatically performs an
-<systemitem>UnmapWindow</systemitem>
-request on it, removes it from its current position in the hierarchy,
-and inserts it as the child of the specified parent.
-The window is placed in the stacking order on top with respect to
-sibling windows.
-</para>
-<para>
-<!-- .LP -->
-After reparenting the specified window,
-<function>XReparentWindow</function>
-causes the X server to generate a
-<symbol>ReparentNotify</symbol>
-event.
-The override_redirect member returned in this event is
-set to the window's corresponding attribute.
-Window manager clients usually should ignore this window if this member
-is set to
-<symbol>True</symbol>.
-Finally, if the specified window was originally mapped,
-the X server automatically performs a
-<systemitem>MapWindow</systemitem>
-request on it.
-</para>
-<para>
-<!-- .LP -->
-The X server performs normal exposure processing on formerly obscured
-windows.
-The X server might not generate
-<symbol>Expose</symbol>
-events for regions from the initial
-<systemitem>UnmapWindow</systemitem>
-request that are immediately obscured by the final
-<systemitem>MapWindow</systemitem>
-request.
-A
-<errorname>BadMatch</errorname>
-error results if:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The new parent window is not on the same screen as
-the old parent window.
- </para>
- </listitem>
- <listitem>
- <para>
-The new parent window is the specified window or an inferior of the
-specified window.
- </para>
- </listitem>
- <listitem>
- <para>
-The new parent is
-<symbol>InputOnly</symbol>,
-and the window is not.
- </para>
- </listitem>
- <listitem>
- <para>
-The specified window has a
-<symbol>ParentRelative</symbol>
-background, and the new parent window is not the same depth as the
-specified window.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-<function>XReparentWindow</function>
-can generate
-<errorname>BadMatch</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect1>
-<sect1 id="Controlling_the_Lifetime_of_a_Window">
-<title>Controlling the Lifetime of a Window</title>
-<!-- .XS -->
-<!-- (SN Controlling the Lifetime of a Window -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The save-set of a client is a list of other clients' windows that,
-if they are inferiors of one of the client's windows at connection close,
-should not be destroyed and should be remapped if they are unmapped.
-For further information about close-connection processing,
-see section 2.6.
-To allow an application's window to survive when a window manager that
-has reparented a window fails,
-Xlib provides the save-set functions that you can
-use to control the longevity of subwindows
-that are normally destroyed when the parent is destroyed.
-For example, a window manager that wants to add decoration
-to a window by adding a frame might reparent an application's
-window.
-When the frame is destroyed,
-the application's window should not be destroyed
-but be returned to its previous place in the window hierarchy.
-</para>
-<para>
-<!-- .LP -->
-The X server automatically removes windows from the save-set
-when they are destroyed.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To add or remove a window from the client's save-set, use
-<function>XChangeSaveSet</function>.
-<indexterm significance="preferred"><primary>XChangeSaveSet</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XChangeSaveSet</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>int<parameter> change_mode</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Wi that you want to add to or delete from the client's save-set -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window (Wi.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>change_mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the mode.
-You can pass
-<symbol>SetModeInsert</symbol>
-or
-<symbol>SetModeDelete</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Depending on the specified mode,
-<function>XChangeSaveSet</function>
-either inserts or deletes the specified window from the client's save-set.
-The specified window must have been created by some other client,
-or a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XChangeSaveSet</function>
-can generate
-<errorname>BadMatch</errorname>,
-<errorname>BadValue</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To add a window to the client's save-set, use
-<function>XAddToSaveSet</function>.
-<indexterm significance="preferred"><primary>XAddToSaveSet</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XAddToSaveSet</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Wi that you want to add to the client's save-set -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window (Wi.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAddToSaveSet</function>
-function adds the specified window to the client's save-set.
-The specified window must have been created by some other client,
-or a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XAddToSaveSet</function>
-can generate
-<errorname>BadMatch</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To remove a window from the client's save-set, use
-<function>XRemoveFromSaveSet</function>.
-<indexterm significance="preferred"><primary>XRemoveFromSaveSet</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XRemoveFromSaveSet</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Wi that you want to delete from the client's save-set -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window (Wi.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XRemoveFromSaveSet</function>
-function removes the specified window from the client's save-set.
-The specified window must have been created by some other client,
-or a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XRemoveFromSaveSet</function>
-can generate
-<errorname>BadMatch</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect1>
-<sect1 id="Managing_Installed_Colormaps">
-<title>Managing Installed Colormaps</title>
-<!-- .XS -->
-<!-- (SN Managing Installed Colormaps -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The X server maintains a list of installed colormaps.
-Windows using these colormaps are guaranteed to display with
-correct colors; windows using other colormaps may or may not display
-with correct colors.
-Xlib provides functions that you can use to install a colormap,
-uninstall a colormap, and obtain a list of installed colormaps.
-</para>
-<para>
-<!-- .LP -->
-At any time,
-there is a subset of the installed maps that is viewed as an ordered list
-and is called the required list.
-The length of the required list is at most M,
-where M is the minimum number of installed colormaps specified for the screen
-in the connection setup.
-The required list is maintained as follows.
-When a colormap is specified to
-<function>XInstallColormap</function>,
-it is added to the head of the list;
-the list is truncated at the tail, if necessary, to keep its length to
-at most M.
-When a colormap is specified to
-<function>XUninstallColormap</function>
-and it is in the required list,
-it is removed from the list.
-A colormap is not added to the required list when it is implicitly installed
-by the X server,
-and the X server cannot implicitly uninstall a colormap that is in the
-required list.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To install a colormap, use
-<function>XInstallColormap</function>.
-<indexterm significance="preferred"><primary>XInstallColormap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XInstallColormap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XInstallColormap</function>
-function installs the specified colormap for its associated screen.
-All windows associated with this colormap immediately display with
-true colors.
-You associated the windows with this colormap when you created them by calling
-<function>XCreateWindow</function>,
-<function>XCreateSimpleWindow</function>,
-<function>XChangeWindowAttributes</function>,
-or
-<function>XSetWindowColormap</function>.
-</para>
-<para>
-<!-- .LP -->
-If the specified colormap is not already an installed colormap,
-the X server generates a
-<symbol>ColormapNotify</symbol>
-event on each window that has that colormap.
-In addition, for every other colormap that is installed as
-a result of a call to
-<function>XInstallColormap</function>,
-the X server generates a
-<symbol>ColormapNotify</symbol>
-event on each window that has that colormap.
-</para>
-<para>
-<!-- .LP -->
-<function>XInstallColormap</function>
-can generate a
-<errorname>BadColor</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To uninstall a colormap, use
-<function>XUninstallColormap</function>.
-<indexterm significance="preferred"><primary>XUninstallColormap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XUninstallColormap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Colormap<parameter> colormap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the colormap.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUninstallColormap</function>
-function removes the specified colormap from the required
-list for its screen.
-As a result,
-the specified colormap might be uninstalled,
-and the X server might implicitly install or uninstall additional colormaps.
-Which colormaps get installed or uninstalled is server dependent
-except that the required list must remain installed.
-</para>
-<para>
-<!-- .LP -->
-If the specified colormap becomes uninstalled,
-the X server generates a
-<symbol>ColormapNotify</symbol>
-event on each window that has that colormap.
-In addition, for every other colormap that is installed or uninstalled as a
-result of a call to
-<function>XUninstallColormap</function>,
-the X server generates a
-<symbol>ColormapNotify</symbol>
-event on each window that has that colormap.
-</para>
-<para>
-<!-- .LP -->
-<function>XUninstallColormap</function>
-can generate a
-<errorname>BadColor</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain a list of the currently installed colormaps for a given screen, use
-<function>XListInstalledColormaps</function>.
-<indexterm significance="preferred"><primary>XListInstalledColormaps</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Colormap *<function>XListInstalledColormaps</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>int<parameter> *num_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Wi that determines the screen -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window (Wi.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of currently installed colormaps.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XListInstalledColormaps</function>
-function returns a list of the currently installed colormaps for the screen
-of the specified window.
-The order of the colormaps in the list is not significant
-and is no explicit indication of the required list.
-When the allocated list is no longer needed,
-free it by using
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XListInstalledColormaps</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Setting_and_Retrieving_the_Font_Search_Path">
-<title>Setting and Retrieving the Font Search Path</title>
-<!-- .XS -->
-<!-- (SN Setting and Retrieving the Font Search Path -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The set of fonts available from a server depends on a font
-search path. Xlib provides functions to set and retrieve the
-search path for a server.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the font search path, use
-<function>XSetFontPath</function>.
-<indexterm significance="preferred"><primary>XSetFontPath</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetFontPath</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> **directories</parameter></paramdef>
- <paramdef>int<parameter> ndirs</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>directories</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the directory path used to look for a font.
-Setting the path to the empty list restores the default path defined
-for the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ndirs</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of directories in the path.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetFontPath</function>
-function defines the directory search path for font lookup.
-There is only one search path per X server, not one per client.
-The encoding and interpretation of the strings are implementation-dependent,
-but typically they specify directories or font servers to be searched
-in the order listed.
-An X server is permitted to cache font information internally;
-for example, it might cache an entire font from a file and not
-check on subsequent opens of that font to see if the underlying
-font file has changed.
-However,
-when the font path is changed,
-the X server is guaranteed to flush all cached information about fonts
-for which there currently are no explicit resource IDs allocated.
-The meaning of an error from this request is implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetFontPath</function>
-can generate a
-<errorname>BadValue</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To get the current font search path, use
-<function>XGetFontPath</function>.
-<indexterm significance="preferred"><primary>XGetFontPath</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char **<function>XGetFontPath</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> *npaths_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>npaths_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of strings in the font path array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetFontPath</function>
-function allocates and returns an array of strings containing the search path.
-The contents of these strings are implementation-dependent
-and are not intended to be interpreted by client applications.
-When it is no longer needed,
-the data in the font path should be freed by using
-<function>XFreeFontPath</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To free data returned by
-<function>XGetFontPath</function>,
-use
-<function>XFreeFontPath</function>.
-<indexterm significance="preferred"><primary>XFreeFontPath</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFreeFontPath</function></funcdef>
- <paramdef>char<parameter> **list</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the array of strings you want to free.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreeFontPath</function>
-function
-frees the data allocated by
-<function>XGetFontPath</function>.
-</para>
-</sect1>
-<sect1 id="Grabbing_the_Server_">
-<title>Grabbing the Server </title>
-<!-- .XS -->
-<!-- (SN Grabbing the Server -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to grab and ungrab the server.
-These functions can be used to control processing of output on other
-connections by the window system server.
-While the server is grabbed,
-no processing of requests or close downs on any other connection will occur.
-A client closing its connection automatically ungrabs the server.
-<indexterm><primary>Menus</primary></indexterm>
-<indexterm><primary>Window</primary><secondary>managers</secondary></indexterm>
-Although grabbing the server is highly discouraged, it is sometimes necessary.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To grab the server, use
-<function>XGrabServer</function>.
-<indexterm><primary>Server</primary><secondary>grabbing</secondary></indexterm>
-<indexterm><primary>Grabbing</primary><secondary>server</secondary></indexterm>
-<indexterm significance="preferred"><primary>XGrabServer</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XGrabServer</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGrabServer</function>
-function disables processing of requests and close downs on all other
-connections than the one this request arrived on.
-You should not grab the X server any more than is absolutely necessary.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To ungrab the server, use
-<function>XUngrabServer</function>.
-<indexterm significance="preferred"><primary>XUngrabServer</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XUngrabServer</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUngrabServer</function>
-function restarts processing of requests and close downs on other connections.
-You should avoid grabbing the X server as much as possible.
-</para>
-</sect1>
-<sect1 id="Killing_Clients">
-<title>Killing Clients</title>
-<!-- .XS -->
-<!-- (SN Killing Clients -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides a function to cause the connection to
-a client to be closed and its resources to be destroyed.
-To destroy a client, use
-<function>XKillClient</function>.
-<indexterm significance="preferred"><primary>XKillClient</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XKillClient</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XID<parameter> resource</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>resource</emphasis>
- </term>
- <listitem>
- <para>
-Specifies any resource associated with the client that you want to destroy or
-<symbol>AllTemporary</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XKillClient</function>
-function
-forces a close down of the client
-that created the resource
-if a valid resource is specified.
-If the client has already terminated in
-either
-<symbol>RetainPermanent</symbol>
-or
-<symbol>RetainTemporary</symbol>
-mode, all of the client's
-resources are destroyed.
-If
-<symbol>AllTemporary</symbol>
-is specified, the resources of all clients that have terminated in
-<symbol>RetainTemporary</symbol>
-are destroyed (see section 2.5).
-This permits implementation of window manager facilities that aid debugging.
-A client can set its close-down mode to
-<symbol>RetainTemporary</symbol>.
-If the client then crashes,
-its windows would not be destroyed.
-The programmer can then inspect the application's window tree
-and use the window manager to destroy the zombie windows.
-</para>
-<para>
-<!-- .LP -->
-<function>XKillClient</function>
-can generate a
-<errorname>BadValue</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Controlling_the_Screen_Saver_">
-<title>Controlling the Screen Saver </title>
-<!-- .XS -->
-<!-- (SN Controlling the Screen Saver -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set or reset the mode
-of the screen saver, to force or activate the screen saver,
-or to obtain the current screen saver values.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the screen saver mode, use
-<function>XSetScreenSaver</function>.
-<indexterm significance="preferred"><primary>XSetScreenSaver</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetScreenSaver</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>inttimeout,<parameter> interval</parameter></paramdef>
- <paramdef>int<parameter> prefer_blanking</parameter></paramdef>
- <paramdef>int<parameter> allow_exposures</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>timeout</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the timeout, in seconds, until the screen saver turns on.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>interval</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the interval, in seconds, between screen saver alterations.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>prefer_blanking</emphasis>
- </term>
- <listitem>
- <para>
-Specifies how to enable screen blanking.
-You can pass
-<symbol>DontPreferBlanking</symbol>,
-<symbol>PreferBlanking</symbol>,
-or
-<symbol>DefaultBlanking</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>allow_exposures</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the screen save control values.
-You can pass
-<symbol>DontAllowExposures</symbol>,
-<symbol>AllowExposures</symbol>,
-or
-<symbol>DefaultExposures</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Timeout and interval are specified in seconds.
-A timeout of 0 disables the screen saver
-(but an activated screen saver is not deactivated),
-and a timeout of &minus;1 restores the default.
-Other negative values generate a
-<errorname>BadValue</errorname>
-error.
-If the timeout value is nonzero,
-<function>XSetScreenSaver</function>
-enables the screen saver.
-An interval of 0 disables the random-pattern motion.
-If no input from devices (keyboard, mouse, and so on) is generated
-for the specified number of timeout seconds once the screen saver is enabled,
-the screen saver is activated.
-</para>
-<para>
-<!-- .LP -->
-For each screen,
-if blanking is preferred and the hardware supports video blanking,
-the screen simply goes blank.
-Otherwise, if either exposures are allowed or the screen can be regenerated
-without sending
-<symbol>Expose</symbol>
-events to clients,
-the screen is tiled with the root window background tile randomly
-re-origined each interval seconds.
-Otherwise, the screens' state do not change,
-and the screen saver is not activated.
-The screen saver is deactivated,
-and all screen states are restored at the next
-keyboard or pointer input or at the next call to
-<function>XForceScreenSaver</function>
-with mode
-<symbol>ScreenSaverReset</symbol>.
-</para>
-<para>
-<!-- .LP -->
-If the server-dependent screen saver method supports periodic change,
-the interval argument serves as a hint about how long the change period
-should be, and zero hints that no periodic change should be made.
-Examples of ways to change the screen include scrambling the colormap
-periodically, moving an icon image around the screen periodically, or tiling
-the screen with the root window background tile, randomly re-origined
-periodically.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetScreenSaver</function>
-can generate a
-<errorname>BadValue</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To force the screen saver on or off, use
-<function>XForceScreenSaver</function>.
-<indexterm significance="preferred"><primary>XForceScreenSaver</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XForceScreenSaver</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> mode</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the mode that is to be applied.
-You can pass
-<symbol>ScreenSaverActive</symbol>
-or
-<symbol>ScreenSaverReset</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If the specified mode is
-<symbol>ScreenSaverActive</symbol>
-and the screen saver currently is deactivated,
-<function>XForceScreenSaver</function>
-activates the screen saver even if the screen saver had been disabled
-with a timeout of zero.
-If the specified mode is
-<symbol>ScreenSaverReset</symbol>
-and the screen saver currently is enabled,
-<function>XForceScreenSaver</function>
-deactivates the screen saver if it was activated,
-and the activation timer is reset to its initial state
-(as if device input had been received).
-</para>
-<para>
-<!-- .LP -->
-<function>XForceScreenSaver</function>
-can generate a
-<errorname>BadValue</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To activate the screen saver, use
-<function>XActivateScreenSaver</function>.
-<indexterm significance="preferred"><primary>XActivateScreenSaver</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XActivateScreenSaver</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To reset the screen saver, use
-<function>XResetScreenSaver</function>.
-<indexterm significance="preferred"><primary>XResetScreenSaver</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XResetScreenSaver</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To get the current screen saver values, use
-<function>XGetScreenSaver</function>.
-<indexterm significance="preferred"><primary>XGetScreenSaver</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XGetScreenSaver</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int*timeout_return,<parameter> *interval_return</parameter></paramdef>
- <paramdef>int<parameter> *prefer_blanking_return</parameter></paramdef>
- <paramdef>int<parameter> *allow_exposures_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>timeout_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the timeout, in seconds, until the screen saver turns on.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>interval_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the interval between screen saver invocations.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>prefer_blanking_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the current screen blanking preference
-(<symbol>DontPreferBlanking</symbol>,
-<symbol>PreferBlanking</symbol>,
-or
-<symbol>DefaultBlanking</symbol>).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>allow_exposures_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the current screen save control value
-(<symbol>DontAllowExposures</symbol>,
-<symbol>AllowExposures</symbol>,
-or
-<symbol>DefaultExposures</symbol>).
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-</para>
-</sect1>
-<sect1 id="Controlling_Host_Access">
-<title>Controlling Host Access</title>
-<!-- .XS -->
-<!-- (SN Controlling Host Access -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This section discusses how to:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Add, get, or remove hosts from the access control list
- </para>
- </listitem>
- <listitem>
- <para>
-Change, enable, or disable access
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-<indexterm><primary>Access control list</primary></indexterm>
-<indexterm><primary>Authentication</primary></indexterm>
-X does not provide any protection on a per-window basis.
-If you find out the resource ID of a resource, you can manipulate it.
-To provide some minimal level of protection, however,
-connections are permitted only from machines you trust.
-This is adequate on single-user workstations but obviously
-breaks down on timesharing machines.
-Although provisions exist in the X protocol for proper connection
-authentication, the lack of a standard authentication server
-leaves host-level access control as the only common mechanism.
-</para>
-<para>
-<!-- .LP -->
-<indexterm><primary>Default Protection</primary></indexterm>
-The initial set of hosts allowed to open connections typically consists of:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The host the window system is running on.
- </para>
- </listitem>
- <listitem>
- <para>
-On <acronym>POSIX</acronym>-conformant systems, each host listed in the
-<filename>/etc/X<replaceable>?</replaceable>.hosts</filename>
-file.
-The ? indicates the number of the
-display.
-<indexterm><primary>Files</primary><secondary><filename>/etc/X<replaceable>?</replaceable>.hosts</filename></secondary></indexterm>
-This file should consist of host names separated by newlines.
-DECnet nodes must terminate in :: to distinguish them from Internet hosts.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-If a host is not in the access control list when the access control
-mechanism is enabled and if the host attempts to establish a connection,
-the server refuses the connection.
-To change the access list,
-the client must reside on the same host as the server and/or must
-have been granted permission in the initial authorization at connection
-setup.
-</para>
-<para>
-<!-- .LP -->
-Servers also can implement other access control policies in addition to
-or in place of this host access facility.
-For further information about other access control implementations,
-see ``X Window System Protocol.''
-</para>
-<sect2 id="Adding_Getting_or_Removing_Hosts">
-<title>Adding, Getting, or Removing Hosts</title>
-<!-- .XS -->
-<!-- (SN Adding, Getting, or Removing Hosts -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to add, get, or remove hosts
-from the access control list.
-All the host access control functions use the
-<structname>XHostAddress</structname>
-structure, which contains:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XHostAddress</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-typedef struct {
- int family; /* for example FamilyInternet */
- int length; /* length of address, in bytes */
- char *address; /* pointer to where to find the address */
-} XHostAddress;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The family member specifies which protocol address family to use
-(for example, <acronym>TCP</acronym>/<acronym>IP</acronym> or DECnet) and can be
-<symbol>FamilyInternet</symbol>,
-<symbol>FamilyInternet6</symbol>,
-<symbol>FamilyServerInterpreted</symbol>,
-<symbol>FamilyDECnet</symbol>,
-or
-<symbol>FamilyChaos</symbol>.
-The length member specifies the length of the address in bytes.
-The address member specifies a pointer to the address.
-</para>
-<para>
-<!-- .LP -->
-For <acronym>TCP</acronym>/<acronym>IP</acronym>, the address should be in network byte order.
-For <acronym>IP</acronym> version 4 addresses, the family should be FamilyInternet
-and the length should be 4 bytes. For <acronym>IP</acronym> version 6 addresses, the
-family should be FamilyInternet6 and the length should be 16 bytes.
-</para>
-<para>
-<!-- .LP -->
-For the DECnet family,
-the server performs no automatic swapping on the address bytes.
-A Phase IV address is 2 bytes long.
-The first byte contains the least significant 8 bits of the node number.
-The second byte contains the most significant 2 bits of the
-node number in the least significant 2 bits of the byte
-and the area in the most significant 6 bits of the byte.
-</para>
-<para>
-<!-- .LP -->
-For the ServerInterpreted family, the length is ignored and the address
-member is a pointer to a
-<structname>XServerInterpretedAddress</structname>
-structure, which contains:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XServerInterpretedAddress</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-typedef struct {
- int typelength; /* length of type string, in bytes */
- int valuelength; /* length of value string, in bytes */
- char *type; /* pointer to where to find the type string */
- char *value; /* pointer to where to find the address */
-} XServerInterpretedAddress;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The type and value members point to strings representing the type and value of
-the server interpreted entry. These strings may not be NULL-terminated so care
-should be used when accessing them. The typelength and valuelength members
-specify the length in byte of the type and value strings.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To add a single host, use
-<function>XAddHost</function>.
-<indexterm significance="preferred"><primary>XAddHost</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XAddHost</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XHostAddress<parameter> *host</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Ho added -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>host</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the host that is to be (Ho.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAddHost</function>
-function adds the specified host to the access control list for that display.
-The server must be on the same host as the client issuing the command, or a
-<errorname>BadAccess</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XAddHost</function>
-can generate
-<errorname>BadAccess</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To add multiple hosts at one time, use
-<function>XAddHosts</function>.
-<indexterm significance="preferred"><primary>XAddHosts</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XAddHosts</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XHostAddress<parameter> *hosts</parameter></paramdef>
- <paramdef>int<parameter> num_hosts</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Ho added -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hosts</emphasis>
- </term>
- <listitem>
- <para>
-Specifies each host that is to be (Ho.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_hosts</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of hosts.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAddHosts</function>
-function adds each specified host to the access control list for that display.
-The server must be on the same host as the client issuing the command, or a
-<errorname>BadAccess</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XAddHosts</function>
-can generate
-<errorname>BadAccess</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain a host list, use
-<function>XListHosts</function>.
-<indexterm significance="preferred"><primary>XListHosts</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XHostAddress *<function>XListHosts</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> *nhosts_return</parameter></paramdef>
- <paramdef>Bool<parameter> *state_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nhosts_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of hosts currently in the access control list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>state_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the state of the access control.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XListHosts</function>
-function returns the current access control list as well as whether the use
-of the list at connection setup was enabled or disabled.
-<function>XListHosts</function>
-allows a program to find out what machines can make connections.
-It also returns a pointer to a list of host structures that
-were allocated by the function.
-When no longer needed,
-this memory should be freed by calling
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To remove a single host, use
-<function>XRemoveHost</function>.
-<indexterm significance="preferred"><primary>XRemoveHost</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XRemoveHost</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XHostAddress<parameter> *host</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Ho removed -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>host</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the host that is to be (Ho.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XRemoveHost</function>
-function removes the specified host from the access control list
-for that display.
-The server must be on the same host as the client process, or a
-<errorname>BadAccess</errorname>
-error results.
-If you remove your machine from the access list,
-you can no longer connect to that server,
-and this operation cannot be reversed unless you reset the server.
-</para>
-<para>
-<!-- .LP -->
-<function>XRemoveHost</function>
-can generate
-<errorname>BadAccess</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To remove multiple hosts at one time, use
-<function>XRemoveHosts</function>.
-<indexterm significance="preferred"><primary>XRemoveHosts</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XRemoveHosts</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XHostAddress<parameter> *hosts</parameter></paramdef>
- <paramdef>int<parameter> num_hosts</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Ho removed -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hosts</emphasis>
- </term>
- <listitem>
- <para>
-Specifies each host that is to be (Ho.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_hosts</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of hosts.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XRemoveHosts</function>
-function removes each specified host from the access control list for that
-display.
-The X server must be on the same host as the client process, or a
-<errorname>BadAccess</errorname>
-error results.
-If you remove your machine from the access list,
-you can no longer connect to that server,
-and this operation cannot be reversed unless you reset the server.
-</para>
-<para>
-<!-- .LP -->
-<function>XRemoveHosts</function>
-can generate
-<errorname>BadAccess</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Changing_Enabling_or_Disabling_Access_Control">
-<title>Changing, Enabling, or Disabling Access Control</title>
-<!-- .XS -->
-<!-- (SN Changing, Enabling, or Disabling Access Control -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to enable, disable,
-or change access control.
-</para>
-<para>
-<!-- .LP -->
-For these functions to execute successfully,
-the client application must reside on the same host as the X server
-and/or have been given permission in the initial authorization
-at connection setup.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To change access control, use
-<function>XSetAccessControl</function>.
-<indexterm significance="preferred"><primary>XSetAccessControl</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetAccessControl</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> mode</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the mode.
-You can pass
-<symbol>EnableAccess</symbol>
-or
-<symbol>DisableAccess</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetAccessControl</function>
-function either enables or disables the use of the access control list
-at each connection setup.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetAccessControl</function>
-can generate
-<errorname>BadAccess</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To enable access control, use
-<function>XEnableAccessControl</function>.
-<indexterm significance="preferred"><primary>XEnableAccessControl</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XEnableAccessControl</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XEnableAccessControl</function>
-function enables the use of the access control list at each connection setup.
-</para>
-<para>
-<!-- .LP -->
-<function>XEnableAccessControl</function>
-can generate a
-<errorname>BadAccess</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To disable access control, use
-<function>XDisableAccessControl</function>.
-<indexterm significance="preferred"><primary>XDisableAccessControl</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDisableAccessControl</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDisableAccessControl</function>
-function disables the use of the access control list at each connection setup.
-</para>
-<para>
-<!-- .LP -->
-<function>XDisableAccessControl</function>
-can generate a
-<errorname>BadAccess</errorname>
-error.
-<!-- .bp -->
-
-</para>
-</sect2>
-</sect1>
-</chapter>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<chapter id="window_and_session_manager_functions">
+<title>Window and Session Manager Functions</title>
+
+<para>
+Although it is difficult to categorize functions as exclusively for an application,
+a window manager, or a session manager, the functions in this chapter are most
+often used by window managers and session managers. It is not expected that
+these functions will be used by most application programs. Xlib provides
+management functions to:
+</para>
+
+<itemizedlist>
+ <listitem><para>Change the parent of a window</para></listitem>
+ <listitem><para>Control the lifetime of a window</para></listitem>
+ <listitem><para>Manage installed colormaps</para></listitem>
+ <listitem><para>Set and retrieve the font search path</para></listitem>
+ <listitem><para>Grab the server</para></listitem>
+ <listitem><para>Kill a client</para></listitem>
+ <listitem><para>Control the screen saver</para></listitem>
+ <listitem><para>Control host access</para></listitem>
+</itemizedlist>
+
+<sect1 id="Changing_the_Parent_of_a_Window">
+<title>Changing the Parent of a Window</title>
+<!-- .XS -->
+<!-- (SN Changing the Parent of a Window -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To change a window's parent to another window on the same screen, use
+<function>XReparentWindow</function>.
+There is no way to move a window between screens.
+<indexterm significance="preferred"><primary>XReparentWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xreparentwindow'>
+<funcprototype>
+ <funcdef><function>XReparentWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Window<parameter> parent</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>parent</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the parent window.
+<!-- .ds Xy \ of the position in the new parent window -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If the specified window is mapped,
+<function>XReparentWindow</function>
+automatically performs an
+<systemitem>UnmapWindow</systemitem>
+request on it, removes it from its current position in the hierarchy,
+and inserts it as the child of the specified parent.
+The window is placed in the stacking order on top with respect to
+sibling windows.
+</para>
+<para>
+<!-- .LP -->
+After reparenting the specified window,
+<function>XReparentWindow</function>
+causes the X server to generate a
+<symbol>ReparentNotify</symbol>
+event.
+The override_redirect member returned in this event is
+set to the window's corresponding attribute.
+Window manager clients usually should ignore this window if this member
+is set to
+<symbol>True</symbol>.
+Finally, if the specified window was originally mapped,
+the X server automatically performs a
+<systemitem>MapWindow</systemitem>
+request on it.
+</para>
+<para>
+<!-- .LP -->
+The X server performs normal exposure processing on formerly obscured
+windows.
+The X server might not generate
+<symbol>Expose</symbol>
+events for regions from the initial
+<systemitem>UnmapWindow</systemitem>
+request that are immediately obscured by the final
+<systemitem>MapWindow</systemitem>
+request.
+A
+<errorname>BadMatch</errorname>
+error results if:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The new parent window is not on the same screen as
+the old parent window.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The new parent window is the specified window or an inferior of the
+specified window.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The new parent is
+<symbol>InputOnly</symbol>,
+and the window is not.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The specified window has a
+<symbol>ParentRelative</symbol>
+background, and the new parent window is not the same depth as the
+specified window.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+<function>XReparentWindow</function>
+can generate
+<errorname>BadMatch</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect1>
+<sect1 id="Controlling_the_Lifetime_of_a_Window">
+<title>Controlling the Lifetime of a Window</title>
+<!-- .XS -->
+<!-- (SN Controlling the Lifetime of a Window -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The save-set of a client is a list of other clients' windows that,
+if they are inferiors of one of the client's windows at connection close,
+should not be destroyed and should be remapped if they are unmapped.
+For further information about close-connection processing,
+see section 2.6.
+To allow an application's window to survive when a window manager that
+has reparented a window fails,
+Xlib provides the save-set functions that you can
+use to control the longevity of subwindows
+that are normally destroyed when the parent is destroyed.
+For example, a window manager that wants to add decoration
+to a window by adding a frame might reparent an application's
+window.
+When the frame is destroyed,
+the application's window should not be destroyed
+but be returned to its previous place in the window hierarchy.
+</para>
+<para>
+<!-- .LP -->
+The X server automatically removes windows from the save-set
+when they are destroyed.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To add or remove a window from the client's save-set, use
+<function>XChangeSaveSet</function>.
+<indexterm significance="preferred"><primary>XChangeSaveSet</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xchangesaveset'>
+<funcprototype>
+ <funcdef><function>XChangeSaveSet</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>int<parameter> change_mode</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Wi that you want to add to or delete from the client's save-set -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window (Wi.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>change_mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the mode.
+You can pass
+<symbol>SetModeInsert</symbol>
+or
+<symbol>SetModeDelete</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Depending on the specified mode,
+<function>XChangeSaveSet</function>
+either inserts or deletes the specified window from the client's save-set.
+The specified window must have been created by some other client,
+or a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XChangeSaveSet</function>
+can generate
+<errorname>BadMatch</errorname>,
+<errorname>BadValue</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To add a window to the client's save-set, use
+<function>XAddToSaveSet</function>.
+<indexterm significance="preferred"><primary>XAddToSaveSet</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xaddtosaveset'>
+<funcprototype>
+ <funcdef><function>XAddToSaveSet</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Wi that you want to add to the client's save-set -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window (Wi.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAddToSaveSet</function>
+function adds the specified window to the client's save-set.
+The specified window must have been created by some other client,
+or a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XAddToSaveSet</function>
+can generate
+<errorname>BadMatch</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To remove a window from the client's save-set, use
+<function>XRemoveFromSaveSet</function>.
+<indexterm significance="preferred"><primary>XRemoveFromSaveSet</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xremovefromsaveset'>
+<funcprototype>
+ <funcdef><function>XRemoveFromSaveSet</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Wi that you want to delete from the client's save-set -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window (Wi.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XRemoveFromSaveSet</function>
+function removes the specified window from the client's save-set.
+The specified window must have been created by some other client,
+or a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XRemoveFromSaveSet</function>
+can generate
+<errorname>BadMatch</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect1>
+<sect1 id="Managing_Installed_Colormaps">
+<title>Managing Installed Colormaps</title>
+<!-- .XS -->
+<!-- (SN Managing Installed Colormaps -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The X server maintains a list of installed colormaps.
+Windows using these colormaps are guaranteed to display with
+correct colors; windows using other colormaps may or may not display
+with correct colors.
+Xlib provides functions that you can use to install a colormap,
+uninstall a colormap, and obtain a list of installed colormaps.
+</para>
+<para>
+<!-- .LP -->
+At any time,
+there is a subset of the installed maps that is viewed as an ordered list
+and is called the required list.
+The length of the required list is at most M,
+where M is the minimum number of installed colormaps specified for the screen
+in the connection setup.
+The required list is maintained as follows.
+When a colormap is specified to
+<function>XInstallColormap</function>,
+it is added to the head of the list;
+the list is truncated at the tail, if necessary, to keep its length to
+at most M.
+When a colormap is specified to
+<function>XUninstallColormap</function>
+and it is in the required list,
+it is removed from the list.
+A colormap is not added to the required list when it is implicitly installed
+by the X server,
+and the X server cannot implicitly uninstall a colormap that is in the
+required list.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To install a colormap, use
+<function>XInstallColormap</function>.
+<indexterm significance="preferred"><primary>XInstallColormap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xinstallcolormap'>
+<funcprototype>
+ <funcdef><function>XInstallColormap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XInstallColormap</function>
+function installs the specified colormap for its associated screen.
+All windows associated with this colormap immediately display with
+true colors.
+You associated the windows with this colormap when you created them by calling
+<function>XCreateWindow</function>,
+<function>XCreateSimpleWindow</function>,
+<function>XChangeWindowAttributes</function>,
+or
+<function>XSetWindowColormap</function>.
+</para>
+<para>
+<!-- .LP -->
+If the specified colormap is not already an installed colormap,
+the X server generates a
+<symbol>ColormapNotify</symbol>
+event on each window that has that colormap.
+In addition, for every other colormap that is installed as
+a result of a call to
+<function>XInstallColormap</function>,
+the X server generates a
+<symbol>ColormapNotify</symbol>
+event on each window that has that colormap.
+</para>
+<para>
+<!-- .LP -->
+<function>XInstallColormap</function>
+can generate a
+<errorname>BadColor</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To uninstall a colormap, use
+<function>XUninstallColormap</function>.
+<indexterm significance="preferred"><primary>XUninstallColormap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xuninstallcolormap'>
+<funcprototype>
+ <funcdef><function>XUninstallColormap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Colormap<parameter> colormap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the colormap.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUninstallColormap</function>
+function removes the specified colormap from the required
+list for its screen.
+As a result,
+the specified colormap might be uninstalled,
+and the X server might implicitly install or uninstall additional colormaps.
+Which colormaps get installed or uninstalled is server dependent
+except that the required list must remain installed.
+</para>
+<para>
+<!-- .LP -->
+If the specified colormap becomes uninstalled,
+the X server generates a
+<symbol>ColormapNotify</symbol>
+event on each window that has that colormap.
+In addition, for every other colormap that is installed or uninstalled as a
+result of a call to
+<function>XUninstallColormap</function>,
+the X server generates a
+<symbol>ColormapNotify</symbol>
+event on each window that has that colormap.
+</para>
+<para>
+<!-- .LP -->
+<function>XUninstallColormap</function>
+can generate a
+<errorname>BadColor</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain a list of the currently installed colormaps for a given screen, use
+<function>XListInstalledColormaps</function>.
+<indexterm significance="preferred"><primary>XListInstalledColormaps</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xlistinstalledcolormaps'>
+<funcprototype>
+ <funcdef>Colormap *<function>XListInstalledColormaps</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>int<parameter> *num_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Wi that determines the screen -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window (Wi.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of currently installed colormaps.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XListInstalledColormaps</function>
+function returns a list of the currently installed colormaps for the screen
+of the specified window.
+The order of the colormaps in the list is not significant
+and is no explicit indication of the required list.
+When the allocated list is no longer needed,
+free it by using
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XListInstalledColormaps</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Setting_and_Retrieving_the_Font_Search_Path">
+<title>Setting and Retrieving the Font Search Path</title>
+<!-- .XS -->
+<!-- (SN Setting and Retrieving the Font Search Path -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The set of fonts available from a server depends on a font
+search path. Xlib provides functions to set and retrieve the
+search path for a server.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the font search path, use
+<function>XSetFontPath</function>.
+<indexterm significance="preferred"><primary>XSetFontPath</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetfontpath'>
+<funcprototype>
+ <funcdef><function>XSetFontPath</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> **directories</parameter></paramdef>
+ <paramdef>int<parameter> ndirs</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>directories</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the directory path used to look for a font.
+Setting the path to the empty list restores the default path defined
+for the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ndirs</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of directories in the path.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetFontPath</function>
+function defines the directory search path for font lookup.
+There is only one search path per X server, not one per client.
+The encoding and interpretation of the strings are implementation-dependent,
+but typically they specify directories or font servers to be searched
+in the order listed.
+An X server is permitted to cache font information internally;
+for example, it might cache an entire font from a file and not
+check on subsequent opens of that font to see if the underlying
+font file has changed.
+However,
+when the font path is changed,
+the X server is guaranteed to flush all cached information about fonts
+for which there currently are no explicit resource IDs allocated.
+The meaning of an error from this request is implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetFontPath</function>
+can generate a
+<errorname>BadValue</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To get the current font search path, use
+<function>XGetFontPath</function>.
+<indexterm significance="preferred"><primary>XGetFontPath</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetfontpath'>
+<funcprototype>
+ <funcdef>char **<function>XGetFontPath</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> *npaths_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>npaths_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of strings in the font path array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetFontPath</function>
+function allocates and returns an array of strings containing the search path.
+The contents of these strings are implementation-dependent
+and are not intended to be interpreted by client applications.
+When it is no longer needed,
+the data in the font path should be freed by using
+<function>XFreeFontPath</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To free data returned by
+<function>XGetFontPath</function>,
+use
+<function>XFreeFontPath</function>.
+<indexterm significance="preferred"><primary>XFreeFontPath</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfreefontpath'>
+<funcprototype>
+ <funcdef><function>XFreeFontPath</function></funcdef>
+ <paramdef>char<parameter> **list</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the array of strings you want to free.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreeFontPath</function>
+function
+frees the data allocated by
+<function>XGetFontPath</function>.
+</para>
+</sect1>
+<sect1 id="Grabbing_the_Server_">
+<title>Grabbing the Server </title>
+<!-- .XS -->
+<!-- (SN Grabbing the Server -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to grab and ungrab the server.
+These functions can be used to control processing of output on other
+connections by the window system server.
+While the server is grabbed,
+no processing of requests or close downs on any other connection will occur.
+A client closing its connection automatically ungrabs the server.
+<indexterm><primary>Menus</primary></indexterm>
+<indexterm><primary>Window</primary><secondary>managers</secondary></indexterm>
+Although grabbing the server is highly discouraged, it is sometimes necessary.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To grab the server, use
+<function>XGrabServer</function>.
+<indexterm><primary>Server</primary><secondary>grabbing</secondary></indexterm>
+<indexterm><primary>Grabbing</primary><secondary>server</secondary></indexterm>
+<indexterm significance="preferred"><primary>XGrabServer</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgrabserver'>
+<funcprototype>
+ <funcdef><function>XGrabServer</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGrabServer</function>
+function disables processing of requests and close downs on all other
+connections than the one this request arrived on.
+You should not grab the X server any more than is absolutely necessary.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To ungrab the server, use
+<function>XUngrabServer</function>.
+<indexterm significance="preferred"><primary>XUngrabServer</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xungrabserver'>
+<funcprototype>
+ <funcdef><function>XUngrabServer</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUngrabServer</function>
+function restarts processing of requests and close downs on other connections.
+You should avoid grabbing the X server as much as possible.
+</para>
+</sect1>
+<sect1 id="Killing_Clients">
+<title>Killing Clients</title>
+<!-- .XS -->
+<!-- (SN Killing Clients -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides a function to cause the connection to
+a client to be closed and its resources to be destroyed.
+To destroy a client, use
+<function>XKillClient</function>.
+<indexterm significance="preferred"><primary>XKillClient</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xkillclient'>
+<funcprototype>
+ <funcdef><function>XKillClient</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XID<parameter> resource</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>resource</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies any resource associated with the client that you want to destroy or
+<symbol>AllTemporary</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XKillClient</function>
+function
+forces a close down of the client
+that created the resource
+if a valid resource is specified.
+If the client has already terminated in
+either
+<symbol>RetainPermanent</symbol>
+or
+<symbol>RetainTemporary</symbol>
+mode, all of the client's
+resources are destroyed.
+If
+<symbol>AllTemporary</symbol>
+is specified, the resources of all clients that have terminated in
+<symbol>RetainTemporary</symbol>
+are destroyed (see section 2.5).
+This permits implementation of window manager facilities that aid debugging.
+A client can set its close-down mode to
+<symbol>RetainTemporary</symbol>.
+If the client then crashes,
+its windows would not be destroyed.
+The programmer can then inspect the application's window tree
+and use the window manager to destroy the zombie windows.
+</para>
+<para>
+<!-- .LP -->
+<function>XKillClient</function>
+can generate a
+<errorname>BadValue</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Controlling_the_Screen_Saver_">
+<title>Controlling the Screen Saver </title>
+<!-- .XS -->
+<!-- (SN Controlling the Screen Saver -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set or reset the mode
+of the screen saver, to force or activate the screen saver,
+or to obtain the current screen saver values.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the screen saver mode, use
+<function>XSetScreenSaver</function>.
+<indexterm significance="preferred"><primary>XSetScreenSaver</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetscreensaver'>
+<funcprototype>
+ <funcdef><function>XSetScreenSaver</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>inttimeout,<parameter> interval</parameter></paramdef>
+ <paramdef>int<parameter> prefer_blanking</parameter></paramdef>
+ <paramdef>int<parameter> allow_exposures</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>timeout</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the timeout, in seconds, until the screen saver turns on.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>interval</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the interval, in seconds, between screen saver alterations.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>prefer_blanking</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies how to enable screen blanking.
+You can pass
+<symbol>DontPreferBlanking</symbol>,
+<symbol>PreferBlanking</symbol>,
+or
+<symbol>DefaultBlanking</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>allow_exposures</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the screen save control values.
+You can pass
+<symbol>DontAllowExposures</symbol>,
+<symbol>AllowExposures</symbol>,
+or
+<symbol>DefaultExposures</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Timeout and interval are specified in seconds.
+A timeout of 0 disables the screen saver
+(but an activated screen saver is not deactivated),
+and a timeout of &minus;1 restores the default.
+Other negative values generate a
+<errorname>BadValue</errorname>
+error.
+If the timeout value is nonzero,
+<function>XSetScreenSaver</function>
+enables the screen saver.
+An interval of 0 disables the random-pattern motion.
+If no input from devices (keyboard, mouse, and so on) is generated
+for the specified number of timeout seconds once the screen saver is enabled,
+the screen saver is activated.
+</para>
+<para>
+<!-- .LP -->
+For each screen,
+if blanking is preferred and the hardware supports video blanking,
+the screen simply goes blank.
+Otherwise, if either exposures are allowed or the screen can be regenerated
+without sending
+<symbol>Expose</symbol>
+events to clients,
+the screen is tiled with the root window background tile randomly
+re-origined each interval seconds.
+Otherwise, the screens' state do not change,
+and the screen saver is not activated.
+The screen saver is deactivated,
+and all screen states are restored at the next
+keyboard or pointer input or at the next call to
+<function>XForceScreenSaver</function>
+with mode
+<symbol>ScreenSaverReset</symbol>.
+</para>
+<para>
+<!-- .LP -->
+If the server-dependent screen saver method supports periodic change,
+the interval argument serves as a hint about how long the change period
+should be, and zero hints that no periodic change should be made.
+Examples of ways to change the screen include scrambling the colormap
+periodically, moving an icon image around the screen periodically, or tiling
+the screen with the root window background tile, randomly re-origined
+periodically.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetScreenSaver</function>
+can generate a
+<errorname>BadValue</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To force the screen saver on or off, use
+<function>XForceScreenSaver</function>.
+<indexterm significance="preferred"><primary>XForceScreenSaver</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xforcescreensaver'>
+<funcprototype>
+ <funcdef><function>XForceScreenSaver</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> mode</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the mode that is to be applied.
+You can pass
+<symbol>ScreenSaverActive</symbol>
+or
+<symbol>ScreenSaverReset</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If the specified mode is
+<symbol>ScreenSaverActive</symbol>
+and the screen saver currently is deactivated,
+<function>XForceScreenSaver</function>
+activates the screen saver even if the screen saver had been disabled
+with a timeout of zero.
+If the specified mode is
+<symbol>ScreenSaverReset</symbol>
+and the screen saver currently is enabled,
+<function>XForceScreenSaver</function>
+deactivates the screen saver if it was activated,
+and the activation timer is reset to its initial state
+(as if device input had been received).
+</para>
+<para>
+<!-- .LP -->
+<function>XForceScreenSaver</function>
+can generate a
+<errorname>BadValue</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To activate the screen saver, use
+<function>XActivateScreenSaver</function>.
+<indexterm significance="preferred"><primary>XActivateScreenSaver</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xactivatescreensaver'>
+<funcprototype>
+ <funcdef><function>XActivateScreenSaver</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To reset the screen saver, use
+<function>XResetScreenSaver</function>.
+<indexterm significance="preferred"><primary>XResetScreenSaver</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xresetscreensaver'>
+<funcprototype>
+ <funcdef><function>XResetScreenSaver</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To get the current screen saver values, use
+<function>XGetScreenSaver</function>.
+<indexterm significance="preferred"><primary>XGetScreenSaver</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetscreensaver'>
+<funcprototype>
+ <funcdef><function>XGetScreenSaver</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int*timeout_return,<parameter> *interval_return</parameter></paramdef>
+ <paramdef>int<parameter> *prefer_blanking_return</parameter></paramdef>
+ <paramdef>int<parameter> *allow_exposures_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>timeout_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the timeout, in seconds, until the screen saver turns on.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>interval_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the interval between screen saver invocations.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>prefer_blanking_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the current screen blanking preference
+(<symbol>DontPreferBlanking</symbol>,
+<symbol>PreferBlanking</symbol>,
+or
+<symbol>DefaultBlanking</symbol>).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>allow_exposures_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the current screen save control value
+(<symbol>DontAllowExposures</symbol>,
+<symbol>AllowExposures</symbol>,
+or
+<symbol>DefaultExposures</symbol>).
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+</para>
+</sect1>
+<sect1 id="Controlling_Host_Access">
+<title>Controlling Host Access</title>
+<!-- .XS -->
+<!-- (SN Controlling Host Access -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This section discusses how to:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Add, get, or remove hosts from the access control list
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Change, enable, or disable access
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+<indexterm><primary>Access control list</primary></indexterm>
+<indexterm><primary>Authentication</primary></indexterm>
+X does not provide any protection on a per-window basis.
+If you find out the resource ID of a resource, you can manipulate it.
+To provide some minimal level of protection, however,
+connections are permitted only from machines you trust.
+This is adequate on single-user workstations but obviously
+breaks down on timesharing machines.
+Although provisions exist in the X protocol for proper connection
+authentication, the lack of a standard authentication server
+leaves host-level access control as the only common mechanism.
+</para>
+<para>
+<!-- .LP -->
+<indexterm><primary>Default Protection</primary></indexterm>
+The initial set of hosts allowed to open connections typically consists of:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The host the window system is running on.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+On <acronym>POSIX</acronym>-conformant systems, each host listed in the
+<filename>/etc/X<replaceable>?</replaceable>.hosts</filename>
+file.
+The ? indicates the number of the
+display.
+<indexterm><primary>Files</primary><secondary><filename>/etc/X<replaceable>?</replaceable>.hosts</filename></secondary></indexterm>
+This file should consist of host names separated by newlines.
+DECnet nodes must terminate in :: to distinguish them from Internet hosts.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+If a host is not in the access control list when the access control
+mechanism is enabled and if the host attempts to establish a connection,
+the server refuses the connection.
+To change the access list,
+the client must reside on the same host as the server and/or must
+have been granted permission in the initial authorization at connection
+setup.
+</para>
+<para>
+<!-- .LP -->
+Servers also can implement other access control policies in addition to
+or in place of this host access facility.
+For further information about other access control implementations,
+see ``X Window System Protocol.''
+</para>
+<sect2 id="Adding_Getting_or_Removing_Hosts">
+<title>Adding, Getting, or Removing Hosts</title>
+<!-- .XS -->
+<!-- (SN Adding, Getting, or Removing Hosts -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to add, get, or remove hosts
+from the access control list.
+All the host access control functions use the
+<structname>XHostAddress</structname>
+structure, which contains:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XHostAddress</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+typedef struct {
+ int family; /* for example FamilyInternet */
+ int length; /* length of address, in bytes */
+ char *address; /* pointer to where to find the address */
+} XHostAddress;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The family member specifies which protocol address family to use
+(for example, <acronym>TCP</acronym>/<acronym>IP</acronym> or DECnet) and can be
+<symbol>FamilyInternet</symbol>,
+<symbol>FamilyInternet6</symbol>,
+<symbol>FamilyServerInterpreted</symbol>,
+<symbol>FamilyDECnet</symbol>,
+or
+<symbol>FamilyChaos</symbol>.
+The length member specifies the length of the address in bytes.
+The address member specifies a pointer to the address.
+</para>
+<para>
+<!-- .LP -->
+For <acronym>TCP</acronym>/<acronym>IP</acronym>, the address should be in network byte order.
+For <acronym>IP</acronym> version 4 addresses, the family should be FamilyInternet
+and the length should be 4 bytes. For <acronym>IP</acronym> version 6 addresses, the
+family should be FamilyInternet6 and the length should be 16 bytes.
+</para>
+<para>
+<!-- .LP -->
+For the DECnet family,
+the server performs no automatic swapping on the address bytes.
+A Phase IV address is 2 bytes long.
+The first byte contains the least significant 8 bits of the node number.
+The second byte contains the most significant 2 bits of the
+node number in the least significant 2 bits of the byte
+and the area in the most significant 6 bits of the byte.
+</para>
+<para>
+<!-- .LP -->
+For the ServerInterpreted family, the length is ignored and the address
+member is a pointer to a
+<structname>XServerInterpretedAddress</structname>
+structure, which contains:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XServerInterpretedAddress</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+typedef struct {
+ int typelength; /* length of type string, in bytes */
+ int valuelength; /* length of value string, in bytes */
+ char *type; /* pointer to where to find the type string */
+ char *value; /* pointer to where to find the address */
+} XServerInterpretedAddress;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The type and value members point to strings representing the type and value of
+the server interpreted entry. These strings may not be NULL-terminated so care
+should be used when accessing them. The typelength and valuelength members
+specify the length in byte of the type and value strings.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To add a single host, use
+<function>XAddHost</function>.
+<indexterm significance="preferred"><primary>XAddHost</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xaddhost'>
+<funcprototype>
+ <funcdef><function>XAddHost</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XHostAddress<parameter> *host</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Ho added -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>host</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the host that is to be (Ho.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAddHost</function>
+function adds the specified host to the access control list for that display.
+The server must be on the same host as the client issuing the command, or a
+<errorname>BadAccess</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XAddHost</function>
+can generate
+<errorname>BadAccess</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To add multiple hosts at one time, use
+<function>XAddHosts</function>.
+<indexterm significance="preferred"><primary>XAddHosts</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xaddhosts'>
+<funcprototype>
+ <funcdef><function>XAddHosts</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XHostAddress<parameter> *hosts</parameter></paramdef>
+ <paramdef>int<parameter> num_hosts</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Ho added -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hosts</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies each host that is to be (Ho.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_hosts</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of hosts.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAddHosts</function>
+function adds each specified host to the access control list for that display.
+The server must be on the same host as the client issuing the command, or a
+<errorname>BadAccess</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XAddHosts</function>
+can generate
+<errorname>BadAccess</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain a host list, use
+<function>XListHosts</function>.
+<indexterm significance="preferred"><primary>XListHosts</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xlisthosts'>
+<funcprototype>
+ <funcdef>XHostAddress *<function>XListHosts</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> *nhosts_return</parameter></paramdef>
+ <paramdef>Bool<parameter> *state_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nhosts_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of hosts currently in the access control list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>state_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the state of the access control.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XListHosts</function>
+function returns the current access control list as well as whether the use
+of the list at connection setup was enabled or disabled.
+<function>XListHosts</function>
+allows a program to find out what machines can make connections.
+It also returns a pointer to a list of host structures that
+were allocated by the function.
+When no longer needed,
+this memory should be freed by calling
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To remove a single host, use
+<function>XRemoveHost</function>.
+<indexterm significance="preferred"><primary>XRemoveHost</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xremovehost'>
+<funcprototype>
+ <funcdef><function>XRemoveHost</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XHostAddress<parameter> *host</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Ho removed -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>host</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the host that is to be (Ho.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XRemoveHost</function>
+function removes the specified host from the access control list
+for that display.
+The server must be on the same host as the client process, or a
+<errorname>BadAccess</errorname>
+error results.
+If you remove your machine from the access list,
+you can no longer connect to that server,
+and this operation cannot be reversed unless you reset the server.
+</para>
+<para>
+<!-- .LP -->
+<function>XRemoveHost</function>
+can generate
+<errorname>BadAccess</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To remove multiple hosts at one time, use
+<function>XRemoveHosts</function>.
+<indexterm significance="preferred"><primary>XRemoveHosts</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xremovehosts'>
+<funcprototype>
+ <funcdef><function>XRemoveHosts</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XHostAddress<parameter> *hosts</parameter></paramdef>
+ <paramdef>int<parameter> num_hosts</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Ho removed -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hosts</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies each host that is to be (Ho.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_hosts</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of hosts.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XRemoveHosts</function>
+function removes each specified host from the access control list for that
+display.
+The X server must be on the same host as the client process, or a
+<errorname>BadAccess</errorname>
+error results.
+If you remove your machine from the access list,
+you can no longer connect to that server,
+and this operation cannot be reversed unless you reset the server.
+</para>
+<para>
+<!-- .LP -->
+<function>XRemoveHosts</function>
+can generate
+<errorname>BadAccess</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Changing_Enabling_or_Disabling_Access_Control">
+<title>Changing, Enabling, or Disabling Access Control</title>
+<!-- .XS -->
+<!-- (SN Changing, Enabling, or Disabling Access Control -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to enable, disable,
+or change access control.
+</para>
+<para>
+<!-- .LP -->
+For these functions to execute successfully,
+the client application must reside on the same host as the X server
+and/or have been given permission in the initial authorization
+at connection setup.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To change access control, use
+<function>XSetAccessControl</function>.
+<indexterm significance="preferred"><primary>XSetAccessControl</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetaccesscontrol'>
+<funcprototype>
+ <funcdef><function>XSetAccessControl</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> mode</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the mode.
+You can pass
+<symbol>EnableAccess</symbol>
+or
+<symbol>DisableAccess</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetAccessControl</function>
+function either enables or disables the use of the access control list
+at each connection setup.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetAccessControl</function>
+can generate
+<errorname>BadAccess</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To enable access control, use
+<function>XEnableAccessControl</function>.
+<indexterm significance="preferred"><primary>XEnableAccessControl</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xenableaccesscontrol'>
+<funcprototype>
+ <funcdef><function>XEnableAccessControl</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XEnableAccessControl</function>
+function enables the use of the access control list at each connection setup.
+</para>
+<para>
+<!-- .LP -->
+<function>XEnableAccessControl</function>
+can generate a
+<errorname>BadAccess</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To disable access control, use
+<function>XDisableAccessControl</function>.
+<indexterm significance="preferred"><primary>XDisableAccessControl</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdisableaccesscontrol'>
+<funcprototype>
+ <funcdef><function>XDisableAccessControl</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDisableAccessControl</function>
+function disables the use of the access control list at each connection setup.
+</para>
+<para>
+<!-- .LP -->
+<function>XDisableAccessControl</function>
+can generate a
+<errorname>BadAccess</errorname>
+error.
+<!-- .bp -->
+
+</para>
+</sect2>
+</sect1>
+</chapter>
diff --git a/libX11/specs/libX11/CH11.xml b/libX11/specs/libX11/CH11.xml
index c8031649a..df8a9630a 100644
--- a/libX11/specs/libX11/CH11.xml
+++ b/libX11/specs/libX11/CH11.xml
@@ -1,2542 +1,2542 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<chapter id="event_handling_functions">
-<title>Event Handling Functions</title>
-
-<para>
-This chapter discusses the Xlib functions you can use to:
-</para>
-<itemizedlist>
- <listitem><para>Select events</para></listitem>
- <listitem><para>Handle the output buffer and the event queue</para></listitem>
- <listitem><para>Select events from the event queue</para></listitem>
- <listitem><para>Send and get events</para></listitem>
- <listitem><para>Handle protocol errors</para></listitem>
-</itemizedlist>
-<note><para>
-Some toolkits use their own event-handling functions and do not allow you to
-interchange these event-handling functions with those in Xlib. For further
-information, see the documentation supplied with the toolkit.
-</para></note>
-
-<para>
-Most applications simply are event loops: they wait for an event, decide what to do with it,
-execute some amount of code that results in changes to the display, and then wait for the next
-event.
-</para>
-
-<sect1 id="Selecting_Events">
-<title>Selecting Events</title>
-<!-- .XS -->
-<!-- (SN Selecting Events -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-There are two ways to select the events you want reported to your client
-application.
-One way is to set the event_mask member of the
-<structname>XSetWindowAttributes</structname>
-structure when you call
-<function>XCreateWindow</function>
-and
-<function>XChangeWindowAttributes</function>.
-Another way is to use
-<function>XSelectInput</function>.
-<indexterm significance="preferred"><primary>XSelectInput</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSelectInput</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>long<parameter> event_mask</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Wi whose events you are interested in -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window (Wi.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event mask.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSelectInput</function>
-function requests that the X server report the events associated with the
-specified event mask.
-Initially, X will not report any of these events.
-Events are reported relative to a window.
-If a window is not interested in a device event, it usually propagates to
-the closest ancestor that is interested,
-unless the do_not_propagate mask prohibits it.
-<indexterm><primary>Event</primary><secondary>propagation</secondary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-Setting the event-mask attribute of a window overrides any previous call
-for the same window but not for other clients.
-Multiple clients can select for the same events on the same window
-with the following restrictions:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Multiple clients can select events on the same window because their event masks
-are disjoint.
-When the X server generates an event, it reports it
-to all interested clients.
- </para>
- </listitem>
- <listitem>
- <para>
-Only one client at a time can select
-<symbol>CirculateRequest</symbol>,
-<symbol>ConfigureRequest</symbol>,
-or
-<symbol>MapRequest</symbol>
-events, which are associated with
-the event mask
-<symbol>SubstructureRedirectMask</symbol>.
- </para>
- </listitem>
- <listitem>
- <para>
-Only one client at a time can select
-a
-<symbol>ResizeRequest</symbol>
-event, which is associated with
-the event mask
-<symbol>ResizeRedirectMask</symbol>.
- </para>
- </listitem>
- <listitem>
- <para>
-Only one client at a time can select a
-<symbol>ButtonPress</symbol>
-event, which is associated with
-the event mask
-<symbol>ButtonPressMask</symbol>.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The server reports the event to all interested clients.
-</para>
-<para>
-<!-- .LP -->
-<function>XSelectInput</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Handling_the_Output_Buffer">
-<title>Handling the Output Buffer</title>
-<!-- .XS -->
-<!-- (SN Handling the Output Buffer -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The output buffer is an area used by Xlib to store requests.
-The functions described in this section flush the output buffer
-if the function would block or not return an event.
-That is, all requests residing in the output buffer that
-have not yet been sent are transmitted to the X server.
-These functions differ in the additional tasks they might perform.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To flush the output buffer, use
-<function>XFlush</function>.
-<indexterm significance="preferred"><primary>XFlush</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFlush</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFlush</function>
-function
-flushes the output buffer.
-Most client applications need not use this function because the output
-buffer is automatically flushed as needed by calls to
-<function>XPending</function>,
-<function>XNextEvent</function>,
-and
-<function>XWindowEvent</function>.
-<indexterm><primary>XPending</primary></indexterm>
-<indexterm><primary>XNextEvent</primary></indexterm>
-<indexterm><primary>XWindowEvent</primary></indexterm>
-Events generated by the server may be enqueued into the library's event queue.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To flush the output buffer and then wait until all requests have been processed,
-use
-<function>XSync</function>.
-<indexterm significance="preferred"><primary>XSync</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSync</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Bool<parameter> discard</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>discard</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value that indicates whether
-<function>XSync</function>
-discards all events on the event queue.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSync</function>
-function
-flushes the output buffer and then waits until all requests have been received
-and processed by the X server.
-Any errors generated must be handled by the error handler.
-For each protocol error received by Xlib,
-<function>XSync</function>
-calls the client application's error handling routine (see section 11.8.2).
-Any events generated by the server are enqueued into the library's
-event queue.
-</para>
-<para>
-<!-- .LP -->
-Finally, if you passed
-<symbol>False</symbol>,
-<function>XSync</function>
-does not discard the events in the queue.
-If you passed
-<symbol>True</symbol>,
-<function>XSync</function>
-discards all events in the queue,
-including those events that were on the queue before
-<function>XSync</function>
-was called.
-Client applications seldom need to call
-<function>XSync</function>.
-</para>
-</sect1>
-<sect1 id="Event_Queue_Management">
-<title>Event Queue Management</title>
-<!-- .XS -->
-<!-- (SN Event Queue Management -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib maintains an event queue.
-However, the operating system also may be buffering data
-in its network connection that is not yet read into the event queue.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To check the number of events in the event queue, use
-<function>XEventsQueued</function>.
-<indexterm significance="preferred"><primary>XEventsQueued</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XEventsQueued</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> mode</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the mode.
-You can pass
-<symbol>QueuedAlready</symbol>,
-<symbol>QueuedAfterFlush</symbol>,
-or
-<symbol>QueuedAfterReading</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If mode is
-<symbol>QueuedAlready</symbol>,
-<function>XEventsQueued</function>
-returns the number of events
-already in the event queue (and never performs a system call).
-If mode is
-<symbol>QueuedAfterFlush</symbol>,
-<function>XEventsQueued</function>
-returns the number of events already in the queue if the number is nonzero.
-If there are no events in the queue,
-<function>XEventsQueued</function>
-flushes the output buffer,
-attempts to read more events out of the application's connection,
-and returns the number read.
-If mode is
-<symbol>QueuedAfterReading</symbol>,
-<function>XEventsQueued</function>
-returns the number of events already in the queue if the number is nonzero.
-If there are no events in the queue,
-<function>XEventsQueued</function>
-attempts to read more events out of the application's connection
-without flushing the output buffer and returns the number read.
-</para>
-<para>
-<!-- .LP -->
-<function>XEventsQueued</function>
-always returns immediately without I/O if there are events already in the
-queue.
-<function>XEventsQueued</function>
-with mode
-<symbol>QueuedAfterFlush</symbol>
-is identical in behavior to
-<function>XPending</function>.
-<function>XEventsQueued</function>
-with mode
-<symbol>QueuedAlready</symbol>
-is identical to the
-<function>XQLength</function>
-function.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To return the number of events that are pending, use
-<function>XPending</function>.
-<indexterm significance="preferred"><primary>XPending</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XPending</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XPending</function>
-function returns the number of events that have been received from the
-X server but have not been removed from the event queue.
-<function>XPending</function>
-is identical to
-<function>XEventsQueued</function>
-with the mode
-<symbol>QueuedAfterFlush</symbol>
-specified.
-</para>
-</sect1>
-<sect1 id="Manipulating_the_Event_Queue">
-<title>Manipulating the Event Queue</title>
-<!-- .XS -->
-<!-- (SN Manipulating the Event Queue -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that let you manipulate the event queue.
-This section discusses how to:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Obtain events, in order, and remove them from the queue
- </para>
- </listitem>
- <listitem>
- <para>
-Peek at events in the queue without removing them
- </para>
- </listitem>
- <listitem>
- <para>
-Obtain events that match the event mask or the arbitrary
-predicate procedures that you provide
- </para>
- </listitem>
-</itemizedlist>
-<sect2 id="Returning_the_Next_Event">
-<title>Returning the Next Event</title>
-<!-- .XS -->
-<!-- (SN Returning the Next Event -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To get the next event and remove it from the queue, use
-<function>XNextEvent</function>.
-<indexterm significance="preferred"><primary>XNextEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XNextEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the next event in the queue.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XNextEvent</function>
-function copies the first event from the event queue into the specified
-<structname>XEvent</structname>
-structure and then removes it from the queue.
-If the event queue is empty,
-<function>XNextEvent</function>
-flushes the output buffer and blocks until an event is received.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To peek at the event queue, use
-<function>XPeekEvent</function>.
-<indexterm significance="preferred"><primary>XPeekEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XPeekEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns a copy of the matched event's associated structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XPeekEvent</function>
-function returns the first event from the event queue,
-but it does not remove the event from the queue.
-If the queue is empty,
-<function>XPeekEvent</function>
-flushes the output buffer and blocks until an event is received.
-It then copies the event into the client-supplied
-<structname>XEvent</structname>
-structure without removing it from the event queue.
-</para>
-</sect2>
-<sect2 id="Selecting_Events_Using_a_Predicate_Procedure">
-<title>Selecting Events Using a Predicate Procedure</title>
-<!-- .XS -->
-<!-- (SN Selecting Events Using a Predicate Procedure -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Each of the functions discussed in this section requires you to
-pass a predicate procedure that determines if an event matches
-what you want.
-Your predicate procedure must decide if the event is useful
-without calling any Xlib functions.
-If the predicate directly or indirectly causes the state of the event queue
-to change, the result is not defined.
-If Xlib has been initialized for threads, the predicate is called with
-the display locked and the result of a call by the predicate to any
-Xlib function that locks the display is not defined unless the caller
-has first called
-<function>XLockDisplay</function>.
-</para>
-<para>
-<!-- .LP -->
-The predicate procedure and its associated arguments are:
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><type>Bool</type></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XEvent<parameter> *event</parameter></paramdef>
- <paramdef>XPointer<parameter> arg</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XEvent</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>arg</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the argument passed in from the
-<function>XIfEvent</function>,
-<function>XCheckIfEvent</function>,
-or
-<function>XPeekIfEvent</function>
-function.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The predicate procedure is called once for each
-event in the queue until it finds a match.
-After finding a match, the predicate procedure must return
-<symbol>True</symbol>.
-If it did not find a match, it must return
-<symbol>False</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To check the event queue for a matching event
-and, if found, remove the event from the queue, use
-<function>XIfEvent</function>.
-<indexterm significance="preferred"><primary>XIfEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XIfEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
- <paramdef>Bool<parameter> (*predicate)()</parameter></paramdef>
- <paramdef>XPointer<parameter> arg</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the matched event's associated structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>predicate</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure that is to be called to determine
-if the next event in the queue matches what you want.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>arg</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the user-supplied argument that will be passed to the predicate procedure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XIfEvent</function>
-function completes only when the specified predicate
-procedure returns
-<symbol>True</symbol>
-for an event,
-which indicates an event in the queue matches.
-<function>XIfEvent</function>
-flushes the output buffer if it blocks waiting for additional events.
-<function>XIfEvent</function>
-removes the matching event from the queue
-and copies the structure into the client-supplied
-<structname>XEvent</structname>
-structure.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To check the event queue for a matching event without blocking, use
-<function>XCheckIfEvent</function>.
-<indexterm significance="preferred"><primary>XCheckIfEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XCheckIfEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
- <paramdef>Bool<parameter> (*predicate)()</parameter></paramdef>
- <paramdef>XPointer<parameter> arg</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns a copy of the matched event's associated structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>predicate</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure that is to be called to determine
-if the next event in the queue matches what you want.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>arg</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the user-supplied argument that will be passed to the predicate procedure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-When the predicate procedure finds a match,
-<function>XCheckIfEvent</function>
-copies the matched event into the client-supplied
-<structname>XEvent</structname>
-structure and returns
-<symbol>True</symbol>.
-(This event is removed from the queue.)
-If the predicate procedure finds no match,
-<function>XCheckIfEvent</function>
-returns
-<symbol>False</symbol>,
-and the output buffer will have been flushed.
-All earlier events stored in the queue are not discarded.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To check the event queue for a matching event
-without removing the event from the queue, use
-<function>XPeekIfEvent</function>.
-<indexterm significance="preferred"><primary>XPeekIfEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XPeekIfEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
- <paramdef>Bool<parameter> (*predicate)()</parameter></paramdef>
- <paramdef>XPointer<parameter> arg</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns a copy of the matched event's associated structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>predicate</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure that is to be called to determine
-if the next event in the queue matches what you want.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>arg</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the user-supplied argument that will be passed to the predicate procedure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XPeekIfEvent</function>
-function returns only when the specified predicate
-procedure returns
-<symbol>True</symbol>
-for an event.
-After the predicate procedure finds a match,
-<function>XPeekIfEvent</function>
-copies the matched event into the client-supplied
-<structname>XEvent</structname>
-structure without removing the event from the queue.
-<function>XPeekIfEvent</function>
-flushes the output buffer if it blocks waiting for additional events.
-</para>
-</sect2>
-<sect2 id="Selecting_Events_Using_a_Window_or_Event_Mask">
-<title>Selecting Events Using a Window or Event Mask</title>
-<!-- .XS -->
-<!-- (SN Selecting Events Using a Window or Event Mask -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The functions discussed in this section let you select events by window
-or event types, allowing you to process events out of order.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To remove the next event that matches both a window and an event mask, use
-<function>XWindowEvent</function>.
-<indexterm significance="preferred"><primary>XWindowEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XWindowEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>long<parameter> event_mask</parameter></paramdef>
- <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Wi whose events you are interested in -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window (Wi.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event mask.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the matched event's associated structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XWindowEvent</function>
-function searches the event queue for an event that matches both the specified
-window and event mask.
-When it finds a match,
-<function>XWindowEvent</function>
-removes that event from the queue and copies it into the specified
-<structname>XEvent</structname>
-structure.
-The other events stored in the queue are not discarded.
-If a matching event is not in the queue,
-<function>XWindowEvent</function>
-flushes the output buffer and blocks until one is received.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To remove the next event that matches both a window and an event mask (if any),
-use
-<function>XCheckWindowEvent</function>.
-<indexterm><primary>XCheckWindowEvent</primary></indexterm>
-This function is similar to
-<function>XWindowEvent</function>
-except that it never blocks and it returns a
-<type>Bool</type>
-indicating if the event was returned.
-<indexterm significance="preferred"><primary>XCheckWindowEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XCheckWindowEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>long<parameter> event_mask</parameter></paramdef>
- <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Wi whose events you are interested in -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window (Wi.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event mask.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the matched event's associated structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCheckWindowEvent</function>
-function searches the event queue and then the events available
-on the server connection for the first event that matches the specified window
-and event mask.
-If it finds a match,
-<function>XCheckWindowEvent</function>
-removes that event, copies it into the specified
-<structname>XEvent</structname>
-structure, and returns
-<symbol>True</symbol>.
-The other events stored in the queue are not discarded.
-If the event you requested is not available,
-<function>XCheckWindowEvent</function>
-returns
-<symbol>False</symbol>,
-and the output buffer will have been flushed.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To remove the next event that matches an event mask, use
-<function>XMaskEvent</function>.
-<indexterm significance="preferred"><primary>XMaskEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XMaskEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>long<parameter> event_mask</parameter></paramdef>
- <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event mask.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the matched event's associated structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XMaskEvent</function>
-function searches the event queue for the events associated with the
-specified mask.
-When it finds a match,
-<function>XMaskEvent</function>
-removes that event and copies it into the specified
-<structname>XEvent</structname>
-structure.
-The other events stored in the queue are not discarded.
-If the event you requested is not in the queue,
-<function>XMaskEvent</function>
-flushes the output buffer and blocks until one is received.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To return and remove the next event that matches an event mask (if any), use
-<function>XCheckMaskEvent</function>.
-This function is similar to
-<function>XMaskEvent</function>
-except that it never blocks and it returns a
-<type>Bool</type>
-indicating if the event was returned.
-<indexterm significance="preferred"><primary>XCheckMaskEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XCheckMaskEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>long<parameter> event_mask</parameter></paramdef>
- <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event mask.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the matched event's associated structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCheckMaskEvent</function>
-function searches the event queue and then any events available on the
-server connection for the first event that matches the specified mask.
-If it finds a match,
-<function>XCheckMaskEvent</function>
-removes that event, copies it into the specified
-<structname>XEvent</structname>
-structure, and returns
-<symbol>True</symbol>.
-The other events stored in the queue are not discarded.
-If the event you requested is not available,
-<function>XCheckMaskEvent</function>
-returns
-<symbol>False</symbol>,
-and the output buffer will have been flushed.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To return and remove the next event in the queue that matches an event type, use
-<function>XCheckTypedEvent</function>.
-<indexterm significance="preferred"><primary>XCheckTypedEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XCheckTypedEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> event_type</parameter></paramdef>
- <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_type</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event type to be compared.
-
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the matched event's associated structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCheckTypedEvent</function>
-function searches the event queue and then any events available
-on the server connection for the first event that matches the specified type.
-If it finds a match,
-<function>XCheckTypedEvent</function>
-removes that event, copies it into the specified
-<structname>XEvent</structname>
-structure, and returns
-<symbol>True</symbol>.
-The other events in the queue are not discarded.
-If the event is not available,
-<function>XCheckTypedEvent</function>
-returns
-<symbol>False</symbol>,
-and the output buffer will have been flushed.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To return and remove the next event in the queue that matches an event type
-and a window, use
-<function>XCheckTypedWindowEvent</function>.
-<indexterm significance="preferred"><primary>XCheckTypedWindowEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XCheckTypedWindowEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>int<parameter> event_type</parameter></paramdef>
- <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_type</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event type to be compared.
-
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the matched event's associated structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCheckTypedWindowEvent</function>
-function searches the event queue and then any events available
-on the server connection for the first event that matches the specified
-type and window.
-If it finds a match,
-<function>XCheckTypedWindowEvent</function>
-removes the event from the queue, copies it into the specified
-<structname>XEvent</structname>
-structure, and returns
-<symbol>True</symbol>.
-The other events in the queue are not discarded.
-If the event is not available,
-<function>XCheckTypedWindowEvent</function>
-returns
-<symbol>False</symbol>,
-and the output buffer will have been flushed.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Putting_an_Event_Back_into_the_Queue">
-<title>Putting an Event Back into the Queue</title>
-<!-- .XS -->
-<!-- (SN Putting an Event Back into the Queue -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To push an event back into the event queue, use
-<function>XPutBackEvent</function>.
-<indexterm significance="preferred"><primary>XPutBackEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XPutBackEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XEvent<parameter> *event</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XPutBackEvent</function>
-function pushes an event back onto the head of the display's event queue
-by copying the event into the queue.
-This can be useful if you read an event and then decide that you
-would rather deal with it later.
-There is no limit to the number of times in succession that you can call
-<function>XPutBackEvent</function>.
-</para>
-</sect1>
-<sect1 id="Sending_Events_to_Other_Applications">
-<title>Sending Events to Other Applications</title>
-<!-- .XS -->
-<!-- (SN Sending Events to Other Applications -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To send an event to a specified window, use
-<function>XSendEvent</function>.
-<indexterm><primary>XSendEvent</primary></indexterm>
-This function is often used in selection processing.
-For example, the owner of a selection should use
-<function>XSendEvent</function>
-to send a
-<symbol>SelectionNotify</symbol>
-event to a requestor when a selection has been converted
-and stored as a property.
-<indexterm significance="preferred"><primary>XSendEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XSendEvent</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Bool<parameter> propagate</parameter></paramdef>
- <paramdef>long<parameter> event_mask</parameter></paramdef>
- <paramdef>XEvent<parameter> *event_send</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window the event is to be sent to, or
-<symbol>PointerWindow</symbol>,
-or
-<symbol>InputFocus</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>propagate</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event mask.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_send</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event that is to be sent.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSendEvent</function>
-function identifies the destination window,
-determines which clients should receive the specified events,
-and ignores any active grabs.
-This function requires you to pass an event mask.
-For a discussion of the valid event mask names,
-see section 10.3.
-This function uses the w argument to identify the destination window as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-If w is
-<symbol>PointerWindow</symbol>,
-the destination window is the window that contains the pointer.
- </para>
- </listitem>
- <listitem>
- <para>
-If w is
-<symbol>InputFocus</symbol>
-and if the focus window contains the pointer,
-the destination window is the window that contains the pointer;
-otherwise, the destination window is the focus window.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-To determine which clients should receive the specified events,
-<function>XSendEvent</function>
-uses the propagate argument as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-If event_mask is the empty set,
-the event is sent to the client that created the destination window.
-If that client no longer exists,
-no event is sent.
- </para>
- </listitem>
- <listitem>
- <para>
-If propagate is
-<symbol>False</symbol>,
-the event is sent to every client selecting on destination any of the event
-types in the event_mask argument.
- </para>
- </listitem>
- <listitem>
- <para>
-If propagate is
-<symbol>True</symbol>
-and no clients have selected on destination any of
-the event types in event-mask, the destination is replaced with the
-closest ancestor of destination for which some client has selected a
-type in event-mask and for which no intervening window has that type in its
-do-not-propagate-mask.
-If no such window exists or if the window is
-an ancestor of the focus window and
-<symbol>InputFocus</symbol>
-was originally specified
-as the destination, the event is not sent to any clients.
-Otherwise, the event is reported to every client selecting on the final
-destination any of the types specified in event_mask.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The event in the
-<structname>XEvent</structname>
-structure must be one of the core events or one of the events
-defined by an extension (or a
-<errorname>BadValue</errorname>
-error results) so that the X server can correctly byte-swap
-the contents as necessary.
-The contents of the event are
-otherwise unaltered and unchecked by the X server except to force send_event to
-<symbol>True</symbol>
-in the forwarded event and to set the serial number in the event correctly;
-therefore these fields
-and the display field are ignored by
-<function>XSendEvent</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XSendEvent</function>
-returns zero if the conversion to wire protocol format failed
-and returns nonzero otherwise.
-</para>
-<para>
-<!-- .LP -->
-<function>XSendEvent</function>
-can generate
-<errorname>BadValue</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect1>
-<sect1 id="Getting_Pointer_Motion_History">
-<title>Getting Pointer Motion History</title>
-<!-- .XS -->
-<!-- (SN Getting Pointer Motion History -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Some X server implementations will maintain a more complete
-history of pointer motion than is reported by event notification.
-The pointer position at each pointer hardware interrupt may be
-stored in a buffer for later retrieval.
-This buffer is called the motion history buffer.
-For example, a few applications, such as paint programs,
-want to have a precise history of where the pointer
-traveled.
-However, this historical information is highly excessive for most applications.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To determine the approximate maximum number of elements in the motion buffer,
-use
-<function>XDisplayMotionBufferSize</function>.
-<indexterm significance="preferred"><primary>XDisplayMotionBufferSize</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>unsigned <type>long</type></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The server may retain the recent history of the pointer motion
-and do so to a finer granularity than is reported by
-<symbol>MotionNotify</symbol>
-events.
-The
-<function>XGetMotionEvents</function>
-function makes this history available.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To get the motion history for a specified window and time, use
-<function>XGetMotionEvents</function>.
-<indexterm significance="preferred"><primary>XGetMotionEvents</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XTimeCoord *<function>XGetMotionEvents</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Timestart,<parameter> stop</parameter></paramdef>
- <paramdef>int<parameter> *nevents_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>start</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>stop</emphasis>
- </term>
- <listitem>
- <para>
-Specify the time interval in which the events are returned from the motion
-history buffer.
-You can pass a timestamp or
-<symbol>CurrentTime</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nevents_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of events from the motion history buffer.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetMotionEvents</function>
-function returns all events in the motion history buffer that fall between the
-specified start and stop times, inclusive, and that have coordinates
-that lie within the specified window (including its borders) at its present
-placement.
-If the server does not support motion history,
-if the start time is later than the stop time,
-or if the start time is in the future,
-no events are returned;
-<function>XGetMotionEvents</function>
-returns NULL.
-If the stop time is in the future, it is equivalent to specifying
-<symbol>CurrentTime</symbol>.
-The return type for this function is a structure defined as follows:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XTimeCoord</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i -->
-<!-- .ta .5i -->
-typedef struct {
- Time time;
- short x, y;
-} XTimeCoord;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The time member is set to the time, in milliseconds.
-The x and y members are set to the coordinates of the pointer and
-are reported relative to the origin
-of the specified window.
-To free the data returned from this call, use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetMotionEvents</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Handling_Protocol_Errors">
-<title>Handling Protocol Errors</title>
-<!-- .XS -->
-<!-- (SN Handling Protocol Errors -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to enable or disable synchronization
-and to use the default error handlers.
-</para>
-<sect2 id="Enabling_or_Disabling_Synchronization">
-<title>Enabling or Disabling Synchronization</title>
-<!-- .XS -->
-<!-- (SN Enabling or Disabling Synchronization -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-When debugging X applications,
-it often is very convenient to require Xlib to behave synchronously
-so that errors are reported as they occur.
-The following function lets you disable or enable synchronous behavior.
-Note that graphics may occur 30 or more times more slowly when
-synchronization is enabled.
-<indexterm><primary>_Xdebug</primary></indexterm>
-On <acronym>POSIX</acronym>-conformant systems,
-there is also a global variable
-<varname>_Xdebug</varname>
-that, if set to nonzero before starting a program under a debugger, will force
-synchronous library behavior.
-</para>
-<para>
-<!-- .LP -->
-After completing their work,
-all Xlib functions that generate protocol requests call what is known as
-an after function.
-<function>XSetAfterFunction</function>
-sets which function is to be called.
-<indexterm significance="preferred"><primary>XSetAfterFunction</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><type>int</type></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> (*procedure)()</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>procedure</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure to be called.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The specified procedure is called with only a display pointer.
-<function>XSetAfterFunction</function>
-returns the previous after function.
-</para>
-<para>
-<!-- .LP -->
-To enable or disable synchronization, use
-<function>XSynchronize</function>.
-<indexterm><primary>Debugging</primary><secondary>synchronous mode</secondary></indexterm>
-<indexterm significance="preferred"><primary>XSynchronize</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><type>int</type></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Bool<parameter> onoff</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>onoff</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value that indicates whether to enable
-or disable synchronization.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSynchronize</function>
-function returns
-the previous after function.
-If onoff is
-<symbol>True</symbol>,
-<function>XSynchronize</function>
-turns on synchronous behavior.
-If onoff is
-<symbol>False</symbol>,
-<function>XSynchronize</function>
-turns off synchronous behavior.
-</para>
-</sect2>
-<sect2 id="Using_the_Default_Error_Handlers">
-<title>Using the Default Error Handlers</title>
-<!-- .XS -->
-<!-- (SN Using the Default Error Handlers -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Debugging</primary><secondary>error handlers</secondary></indexterm>
-<indexterm><primary>Error</primary><secondary>handlers</secondary></indexterm>
-There are two default error handlers in Xlib:
-one to handle typically fatal conditions (for example,
-the connection to a display server dying because a machine crashed)
-and one to handle protocol errors from the X server.
-These error handlers can be changed to user-supplied routines if you
-prefer your own error handling and can be changed as often as you like.
-If either function is passed a NULL pointer, it will
-reinvoke the default handler.
-The action of the default handlers is to print an explanatory
-message and exit.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the error handler, use
-<function>XSetErrorHandler</function>.
-<indexterm significance="preferred"><primary>XSetErrorHandler</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int *<function>XSetErrorHandler</function></funcdef>
- <paramdef>int <parameter> *handler</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>handler</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the program's supplied error handler.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Xlib generally calls the program's
-supplied error handler whenever an error is received.
-It is not called on
-<errorname>BadName</errorname>
-errors from
-<systemitem>OpenFont</systemitem>,
-<systemitem>LookupColor</systemitem>,
-or
-<systemitem>AllocNamedColor</systemitem>
-protocol requests or on
-<errorname>BadFont</errorname>
-errors from a
-<systemitem>QueryFont</systemitem>
-protocol request.
-These errors generally are reflected back to the program through the
-procedural interface.
-Because this condition is not assumed to be fatal,
-it is acceptable for your error handler to return;
-the returned value is ignored.
-However, the error handler should not
-call any functions (directly or indirectly) on the display
-that will generate protocol requests or that will look for input events.
-The previous error handler is returned.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XErrorEvent</structname>
-structure contains:
-<indexterm><primary>Debugging</primary><secondary>error event</secondary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XErrorEvent</primary></indexterm>
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- int type;
- Display *display; /* Display the event was read from */
- unsigned long serial; /* serial number of failed request */
- unsigned char error_code; /* error code of failed request */
- unsigned char request_code; /* Major op-code of failed request */
- unsigned char minor_code; /* Minor op-code of failed request */
- XID resourceid; /* resource id */
-} XErrorEvent;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<indexterm><primary>Serial Number</primary></indexterm>
-The serial member is the number of requests, starting from one,
-sent over the network connection since it was opened.
-It is the number that was the value of
-<function>NextRequest</function>
-immediately before the failing call was made.
-The request_code member is a protocol request
-of the procedure that failed, as defined in
-&lt; X11/Xproto.h .&gt;
-The following error codes can be returned by the functions described in this
-chapter:
-</para>
-<!-- .br -->
-<!-- .ne 13 -->
-<indexterm><primary>Debugging</primary><secondary>error numbers</secondary></indexterm>
-<indexterm><primary>Error</primary><secondary>codes</secondary></indexterm>
-<!-- .\".CP T 3 -->
-<!-- .\"Error Codes -->
-<indexterm significance="preferred"><primary>BadAccess</primary></indexterm>
-<indexterm significance="preferred"><primary>BadAlloc</primary></indexterm>
-<indexterm significance="preferred"><primary>BadAtom</primary></indexterm>
-<indexterm significance="preferred"><primary>BadColor</primary></indexterm>
-<indexterm significance="preferred"><primary>BadCursor</primary></indexterm>
-<indexterm significance="preferred"><primary>BadDrawable</primary></indexterm>
-<indexterm significance="preferred"><primary>BadFont</primary></indexterm>
-<indexterm significance="preferred"><primary>BadGC</primary></indexterm>
-<indexterm significance="preferred"><primary>BadIDChoice</primary></indexterm>
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <thead>
- <row>
- <entry>Error Code</entry>
- <entry>Description</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry><errorname>BadAccess</errorname></entry>
- <entry>A client attempts to grab a key/button combination already grabbed
- by another client.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>A client attempts to free a colormap entry that it had not already allocated
- or to free an entry in a colormap that was created with all entries writable.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>A client attempts to store into a read-only or unallocated colormap entry.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>A client attempts to modify the access control list from other than the local
- (or otherwise authorized) host.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>A client attempts to select an event type that another client
- has already selected.</entry>
- </row>
- <row>
- <entry><errorname>BadAlloc</errorname></entry>
- <entry>The server fails to allocate the requested resource.
- Note that the explicit listing of
- <errorname>BadAlloc</errorname>
- errors in requests only covers allocation errors at a very coarse level
- and is not intended to (nor can it in practice hope to) cover all cases of
- a server running out of allocation space in the middle of service.
- The semantics when a server runs out of allocation space are left unspecified,
- but a server may generate a
- <errorname>BadAlloc</errorname>
- error on any request for this reason,
- and clients should be prepared to receive such errors and handle or discard
- them.</entry>
- </row>
- <row>
- <entry><errorname>BadAtom</errorname></entry>
- <entry>A value for an atom argument does not name a defined atom.</entry>
- </row>
- <row>
- <entry><errorname>BadColor</errorname></entry>
- <entry>A value for a colormap argument does not name a defined colormap.</entry>
- </row>
- <row>
- <entry><errorname>BadCursor</errorname></entry>
- <entry>A value for a cursor argument does not name a defined cursor.</entry>
- </row>
- <row>
- <entry><errorname>BadDrawable</errorname></entry>
- <entry>A value for a drawable argument does not name a defined window or pixmap.</entry>
- </row>
- <row>
- <entry><errorname>BadFont</errorname></entry>
- <entry>A value for a font argument does not name a defined font (or, in some cases,
- <type>GContext</type>).</entry>
- </row>
- <row>
- <entry><errorname>BadGC</errorname></entry>
- <entry>A value for a
- <type>GContext</type>
- argument does not name a defined
- <type>GContext</type>.</entry>
- </row>
- <row>
- <entry><errorname>BadIDChoice</errorname></entry>
- <entry>The value chosen for a resource identifier either is not included in the
- range assigned to the client or is already in use.
- Under normal circumstances,
- this cannot occur and should be considered a server or Xlib error.</entry>
- </row>
- <row>
- <entry><errorname>BadImplementation</errorname></entry>
- <entry>The server does not implement some aspect of the request.
- A server that generates this error for a core request is deficient.
- As such, this error is not listed for any of the requests,
- but clients should be prepared to receive such errors
- and handle or discard them.</entry>
- </row>
- <row>
- <entry><errorname>BadLength</errorname></entry>
- <entry>The length of a request is shorter or longer than that required to
- contain the arguments.
- This is an internal Xlib or server error.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>
- The length of a request exceeds the maximum length accepted by the server.</entry>
- </row>
- <row>
- <entry><errorname>BadMatch</errorname></entry>
- <entry>In a graphics request,
- the root and depth of the graphics context do not match those of the drawable.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>An <symbol>InputOnly</symbol> window is used as a drawable.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>
- Some argument or pair of arguments has the correct type and range,
- but it fails to match in some other way required by the request.</entry>
- </row>
- <row>
- <entry></entry>
- <entry>An <symbol>InputOnly</symbol>
- window lacks this attribute.</entry>
- </row>
- <row>
- <entry><errorname>BadName</errorname></entry>
- <entry>A font or color of the specified name does not exist.</entry>
- </row>
- <row>
- <entry><errorname>BadPixmap</errorname></entry>
- <entry>A value for a pixmap argument does not name a defined pixmap.</entry>
- </row>
- <row>
- <entry><errorname>BadRequest</errorname></entry>
- <entry>The major or minor opcode does not specify a valid request.
- This usually is an Xlib or server error.</entry>
- </row>
- <row>
- <entry><errorname>BadValue</errorname></entry>
- <entry>Some numeric value falls outside of the range of values accepted
- by the request.
- Unless a specific range is specified for an argument,
- the full range defined by the argument's type is accepted.
- Any argument defined as a set of alternatives typically can generate
- this error (due to the encoding).</entry>
- </row>
- <row>
- <entry><errorname>BadWindow</errorname></entry>
- <entry>A value for a window argument does not name a defined window.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<indexterm significance="preferred"><primary>BadImplementation</primary></indexterm>
-<indexterm significance="preferred"><primary>BadLength</primary></indexterm>
-<indexterm significance="preferred"><primary>BadMatch</primary></indexterm>
-<indexterm significance="preferred"><primary>BadName</primary></indexterm>
-<indexterm significance="preferred"><primary>BadPixmap</primary></indexterm>
-<indexterm significance="preferred"><primary>BadRequest</primary></indexterm>
-<indexterm significance="preferred"><primary>BadValue</primary></indexterm>
-<indexterm significance="preferred"><primary>BadWindow</primary></indexterm>
-<!-- .NT Note -->
-
-<note>
-<para>
-The
-<errorname>BadAtom</errorname>,
-<errorname>BadColor</errorname>,
-<errorname>BadCursor</errorname>,
-<errorname>BadDrawable</errorname>,
-<errorname>BadFont</errorname>,
-<errorname>BadGC</errorname>,
-<errorname>BadPixmap</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors are also used when the argument type is extended by a set of
-fixed alternatives.
-</para>
-</note>
-
-<!-- .NE -->
-<!-- .sp -->
-<para>
-<!-- .LP -->
-To obtain textual descriptions of the specified error code, use
-<function>XGetErrorText</function>.
-<indexterm significance="preferred"><primary>XGetErrorText</primary></indexterm>
-<indexterm><primary>Debugging</primary><secondary>error message strings</secondary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XGetErrorText</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> code</parameter></paramdef>
- <paramdef>char<parameter> *buffer_return</parameter></paramdef>
- <paramdef>int<parameter> length</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>code</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the error code for which you want to obtain a description.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>buffer_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the error description.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>length</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the size of the buffer.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetErrorText</function>
-function copies a null-terminated string describing the specified error code
-into the specified buffer.
-The returned text is in the encoding of the current locale.
-It is recommended that you use this function to obtain an error description
-because extensions to Xlib may define their own error codes
-and error strings.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain error messages from the error database, use
-<function>XGetErrorDatabaseText</function>.
-<indexterm significance="preferred"><primary>XGetErrorDatabaseText</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XGetErrorDatabaseText</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char*name,<parameter> *message</parameter></paramdef>
- <paramdef>char<parameter> *default_string</parameter></paramdef>
- <paramdef>char<parameter> *buffer_return</parameter></paramdef>
- <paramdef>int<parameter> length</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the name of the application.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>message</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the type of the error message.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>default_string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the default error message if none is found in the database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>buffer_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the error description.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>length</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the size of the buffer.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetErrorDatabaseText</function>
-function returns a null-terminated message
-(or the default message) from the error message
-database.
-Xlib uses this function internally to look up its error messages.
-The text in the default_string argument is assumed
-to be in the encoding of the current locale,
-and the text stored in the buffer_return argument
-is in the encoding of the current locale.
-</para>
-<para>
-<!-- .LP -->
-The name argument should generally be the name of your application.
-The message argument should indicate which type of error message you want.
-If the name and message are not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-Xlib uses three predefined ``application names'' to report errors.
-In these names,
-uppercase and lowercase matter.
-<variablelist>
- <varlistentry>
- <term>
- XProtoError
- </term>
- <listitem>
- <para>
-The protocol error number is used as a string for the message argument.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- XlibMessage
- </term>
- <listitem>
- <para>
-These are the message strings that are used internally by the library.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- XRequest
- </term>
- <listitem>
- <para>
-For a core protocol request,
-the major request protocol number is used for the message argument.
-For an extension request,
-the extension name (as given by
-<function>InitExtension</function>)
-followed by a period (.) and the minor request protocol number
-is used for the message argument.
-If no string is found in the error database,
-the default_string is returned to the buffer argument.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To report an error to the user when the requested display does not exist, use
-<function>XDisplayName</function>.
-<indexterm significance="preferred"><primary>XDisplayName</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XDisplayName</function></funcdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDisplayName</function>
-function returns the name of the display that
-<function>XOpenDisplay</function>
-would attempt to use.
-If a NULL string is specified,
-<function>XDisplayName</function>
-looks in the environment for the display and returns the display name that
-<function>XOpenDisplay</function>
-would attempt to use.
-This makes it easier to report to the user precisely which display the
-program attempted to open when the initial connection attempt failed.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To handle fatal I/O errors, use
-<function>XSetIOErrorHandler</function>.
-<indexterm significance="preferred"><primary>XSetIOErrorHandler</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><type>int</type></funcdef>
- <paramdef>int(*handler)(Display<parameter> *)</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>handler</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the program's supplied error handler.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetIOErrorHandler</function>
-sets the fatal I/O error handler.
-Xlib calls the program's supplied error handler if any sort of system call
-error occurs (for example, the connection to the server was lost).
-This is assumed to be a fatal condition,
-and the called routine should not return.
-If the I/O error handler does return,
-the client process exits.
-</para>
-<para>
-<!-- .LP -->
-Note that the previous error handler is returned.
-<!-- .bp -->
-
-</para>
-</sect2>
-</sect1>
-</chapter>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<chapter id="event_handling_functions">
+<title>Event Handling Functions</title>
+
+<para>
+This chapter discusses the Xlib functions you can use to:
+</para>
+<itemizedlist>
+ <listitem><para>Select events</para></listitem>
+ <listitem><para>Handle the output buffer and the event queue</para></listitem>
+ <listitem><para>Select events from the event queue</para></listitem>
+ <listitem><para>Send and get events</para></listitem>
+ <listitem><para>Handle protocol errors</para></listitem>
+</itemizedlist>
+<note><para>
+Some toolkits use their own event-handling functions and do not allow you to
+interchange these event-handling functions with those in Xlib. For further
+information, see the documentation supplied with the toolkit.
+</para></note>
+
+<para>
+Most applications simply are event loops: they wait for an event, decide what to do with it,
+execute some amount of code that results in changes to the display, and then wait for the next
+event.
+</para>
+
+<sect1 id="Selecting_Events">
+<title>Selecting Events</title>
+<!-- .XS -->
+<!-- (SN Selecting Events -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+There are two ways to select the events you want reported to your client
+application.
+One way is to set the event_mask member of the
+<structname>XSetWindowAttributes</structname>
+structure when you call
+<function>XCreateWindow</function>
+and
+<function>XChangeWindowAttributes</function>.
+Another way is to use
+<function>XSelectInput</function>.
+<indexterm significance="preferred"><primary>XSelectInput</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xselectinput'>
+<funcprototype>
+ <funcdef><function>XSelectInput</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>long<parameter> event_mask</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Wi whose events you are interested in -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window (Wi.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event mask.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSelectInput</function>
+function requests that the X server report the events associated with the
+specified event mask.
+Initially, X will not report any of these events.
+Events are reported relative to a window.
+If a window is not interested in a device event, it usually propagates to
+the closest ancestor that is interested,
+unless the do_not_propagate mask prohibits it.
+<indexterm><primary>Event</primary><secondary>propagation</secondary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+Setting the event-mask attribute of a window overrides any previous call
+for the same window but not for other clients.
+Multiple clients can select for the same events on the same window
+with the following restrictions:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Multiple clients can select events on the same window because their event masks
+are disjoint.
+When the X server generates an event, it reports it
+to all interested clients.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Only one client at a time can select
+<symbol>CirculateRequest</symbol>,
+<symbol>ConfigureRequest</symbol>,
+or
+<symbol>MapRequest</symbol>
+events, which are associated with
+the event mask
+<symbol>SubstructureRedirectMask</symbol>.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Only one client at a time can select
+a
+<symbol>ResizeRequest</symbol>
+event, which is associated with
+the event mask
+<symbol>ResizeRedirectMask</symbol>.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Only one client at a time can select a
+<symbol>ButtonPress</symbol>
+event, which is associated with
+the event mask
+<symbol>ButtonPressMask</symbol>.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The server reports the event to all interested clients.
+</para>
+<para>
+<!-- .LP -->
+<function>XSelectInput</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Handling_the_Output_Buffer">
+<title>Handling the Output Buffer</title>
+<!-- .XS -->
+<!-- (SN Handling the Output Buffer -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The output buffer is an area used by Xlib to store requests.
+The functions described in this section flush the output buffer
+if the function would block or not return an event.
+That is, all requests residing in the output buffer that
+have not yet been sent are transmitted to the X server.
+These functions differ in the additional tasks they might perform.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To flush the output buffer, use
+<function>XFlush</function>.
+<indexterm significance="preferred"><primary>XFlush</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xflush'>
+<funcprototype>
+ <funcdef><function>XFlush</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFlush</function>
+function
+flushes the output buffer.
+Most client applications need not use this function because the output
+buffer is automatically flushed as needed by calls to
+<function>XPending</function>,
+<function>XNextEvent</function>,
+and
+<function>XWindowEvent</function>.
+<indexterm><primary>XPending</primary></indexterm>
+<indexterm><primary>XNextEvent</primary></indexterm>
+<indexterm><primary>XWindowEvent</primary></indexterm>
+Events generated by the server may be enqueued into the library's event queue.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To flush the output buffer and then wait until all requests have been processed,
+use
+<function>XSync</function>.
+<indexterm significance="preferred"><primary>XSync</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsync'>
+<funcprototype>
+ <funcdef><function>XSync</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Bool<parameter> discard</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>discard</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value that indicates whether
+<function>XSync</function>
+discards all events on the event queue.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSync</function>
+function
+flushes the output buffer and then waits until all requests have been received
+and processed by the X server.
+Any errors generated must be handled by the error handler.
+For each protocol error received by Xlib,
+<function>XSync</function>
+calls the client application's error handling routine (see section 11.8.2).
+Any events generated by the server are enqueued into the library's
+event queue.
+</para>
+<para>
+<!-- .LP -->
+Finally, if you passed
+<symbol>False</symbol>,
+<function>XSync</function>
+does not discard the events in the queue.
+If you passed
+<symbol>True</symbol>,
+<function>XSync</function>
+discards all events in the queue,
+including those events that were on the queue before
+<function>XSync</function>
+was called.
+Client applications seldom need to call
+<function>XSync</function>.
+</para>
+</sect1>
+<sect1 id="Event_Queue_Management">
+<title>Event Queue Management</title>
+<!-- .XS -->
+<!-- (SN Event Queue Management -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib maintains an event queue.
+However, the operating system also may be buffering data
+in its network connection that is not yet read into the event queue.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To check the number of events in the event queue, use
+<function>XEventsQueued</function>.
+<indexterm significance="preferred"><primary>XEventsQueued</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xeventsqueued'>
+<funcprototype>
+ <funcdef>int <function>XEventsQueued</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> mode</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the mode.
+You can pass
+<symbol>QueuedAlready</symbol>,
+<symbol>QueuedAfterFlush</symbol>,
+or
+<symbol>QueuedAfterReading</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If mode is
+<symbol>QueuedAlready</symbol>,
+<function>XEventsQueued</function>
+returns the number of events
+already in the event queue (and never performs a system call).
+If mode is
+<symbol>QueuedAfterFlush</symbol>,
+<function>XEventsQueued</function>
+returns the number of events already in the queue if the number is nonzero.
+If there are no events in the queue,
+<function>XEventsQueued</function>
+flushes the output buffer,
+attempts to read more events out of the application's connection,
+and returns the number read.
+If mode is
+<symbol>QueuedAfterReading</symbol>,
+<function>XEventsQueued</function>
+returns the number of events already in the queue if the number is nonzero.
+If there are no events in the queue,
+<function>XEventsQueued</function>
+attempts to read more events out of the application's connection
+without flushing the output buffer and returns the number read.
+</para>
+<para>
+<!-- .LP -->
+<function>XEventsQueued</function>
+always returns immediately without I/O if there are events already in the
+queue.
+<function>XEventsQueued</function>
+with mode
+<symbol>QueuedAfterFlush</symbol>
+is identical in behavior to
+<function>XPending</function>.
+<function>XEventsQueued</function>
+with mode
+<symbol>QueuedAlready</symbol>
+is identical to the
+<function>XQLength</function>
+function.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To return the number of events that are pending, use
+<function>XPending</function>.
+<indexterm significance="preferred"><primary>XPending</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xpending'>
+<funcprototype>
+ <funcdef>int <function>XPending</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XPending</function>
+function returns the number of events that have been received from the
+X server but have not been removed from the event queue.
+<function>XPending</function>
+is identical to
+<function>XEventsQueued</function>
+with the mode
+<symbol>QueuedAfterFlush</symbol>
+specified.
+</para>
+</sect1>
+<sect1 id="Manipulating_the_Event_Queue">
+<title>Manipulating the Event Queue</title>
+<!-- .XS -->
+<!-- (SN Manipulating the Event Queue -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that let you manipulate the event queue.
+This section discusses how to:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Obtain events, in order, and remove them from the queue
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Peek at events in the queue without removing them
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Obtain events that match the event mask or the arbitrary
+predicate procedures that you provide
+ </para>
+ </listitem>
+</itemizedlist>
+<sect2 id="Returning_the_Next_Event">
+<title>Returning the Next Event</title>
+<!-- .XS -->
+<!-- (SN Returning the Next Event -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To get the next event and remove it from the queue, use
+<function>XNextEvent</function>.
+<indexterm significance="preferred"><primary>XNextEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xnextevent'>
+<funcprototype>
+ <funcdef><function>XNextEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the next event in the queue.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XNextEvent</function>
+function copies the first event from the event queue into the specified
+<structname>XEvent</structname>
+structure and then removes it from the queue.
+If the event queue is empty,
+<function>XNextEvent</function>
+flushes the output buffer and blocks until an event is received.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To peek at the event queue, use
+<function>XPeekEvent</function>.
+<indexterm significance="preferred"><primary>XPeekEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xpeekevent'>
+<funcprototype>
+ <funcdef><function>XPeekEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns a copy of the matched event's associated structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XPeekEvent</function>
+function returns the first event from the event queue,
+but it does not remove the event from the queue.
+If the queue is empty,
+<function>XPeekEvent</function>
+flushes the output buffer and blocks until an event is received.
+It then copies the event into the client-supplied
+<structname>XEvent</structname>
+structure without removing it from the event queue.
+</para>
+</sect2>
+<sect2 id="Selecting_Events_Using_a_Predicate_Procedure">
+<title>Selecting Events Using a Predicate Procedure</title>
+<!-- .XS -->
+<!-- (SN Selecting Events Using a Predicate Procedure -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Each of the functions discussed in this section requires you to
+pass a predicate procedure that determines if an event matches
+what you want.
+Your predicate procedure must decide if the event is useful
+without calling any Xlib functions.
+If the predicate directly or indirectly causes the state of the event queue
+to change, the result is not defined.
+If Xlib has been initialized for threads, the predicate is called with
+the display locked and the result of a call by the predicate to any
+Xlib function that locks the display is not defined unless the caller
+has first called
+<function>XLockDisplay</function>.
+</para>
+<para>
+<!-- .LP -->
+The predicate procedure and its associated arguments are:
+<!-- .sM -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef><type>Bool</type></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event</parameter></paramdef>
+ <paramdef>XPointer<parameter> arg</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XEvent</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>arg</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the argument passed in from the
+<function>XIfEvent</function>,
+<function>XCheckIfEvent</function>,
+or
+<function>XPeekIfEvent</function>
+function.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The predicate procedure is called once for each
+event in the queue until it finds a match.
+After finding a match, the predicate procedure must return
+<symbol>True</symbol>.
+If it did not find a match, it must return
+<symbol>False</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To check the event queue for a matching event
+and, if found, remove the event from the queue, use
+<function>XIfEvent</function>.
+<indexterm significance="preferred"><primary>XIfEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xifevent'>
+<funcprototype>
+ <funcdef><function>XIfEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
+ <paramdef>Bool<parameter> (*predicate)()</parameter></paramdef>
+ <paramdef>XPointer<parameter> arg</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the matched event's associated structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>predicate</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure that is to be called to determine
+if the next event in the queue matches what you want.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>arg</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the user-supplied argument that will be passed to the predicate procedure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XIfEvent</function>
+function completes only when the specified predicate
+procedure returns
+<symbol>True</symbol>
+for an event,
+which indicates an event in the queue matches.
+<function>XIfEvent</function>
+flushes the output buffer if it blocks waiting for additional events.
+<function>XIfEvent</function>
+removes the matching event from the queue
+and copies the structure into the client-supplied
+<structname>XEvent</structname>
+structure.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To check the event queue for a matching event without blocking, use
+<function>XCheckIfEvent</function>.
+<indexterm significance="preferred"><primary>XCheckIfEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcheckifevent'>
+<funcprototype>
+ <funcdef>Bool <function>XCheckIfEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
+ <paramdef>Bool<parameter> (*predicate)()</parameter></paramdef>
+ <paramdef>XPointer<parameter> arg</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns a copy of the matched event's associated structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>predicate</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure that is to be called to determine
+if the next event in the queue matches what you want.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>arg</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the user-supplied argument that will be passed to the predicate procedure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+When the predicate procedure finds a match,
+<function>XCheckIfEvent</function>
+copies the matched event into the client-supplied
+<structname>XEvent</structname>
+structure and returns
+<symbol>True</symbol>.
+(This event is removed from the queue.)
+If the predicate procedure finds no match,
+<function>XCheckIfEvent</function>
+returns
+<symbol>False</symbol>,
+and the output buffer will have been flushed.
+All earlier events stored in the queue are not discarded.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To check the event queue for a matching event
+without removing the event from the queue, use
+<function>XPeekIfEvent</function>.
+<indexterm significance="preferred"><primary>XPeekIfEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xpeekifevent'>
+<funcprototype>
+ <funcdef><function>XPeekIfEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
+ <paramdef>Bool<parameter> (*predicate)()</parameter></paramdef>
+ <paramdef>XPointer<parameter> arg</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns a copy of the matched event's associated structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>predicate</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure that is to be called to determine
+if the next event in the queue matches what you want.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>arg</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the user-supplied argument that will be passed to the predicate procedure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XPeekIfEvent</function>
+function returns only when the specified predicate
+procedure returns
+<symbol>True</symbol>
+for an event.
+After the predicate procedure finds a match,
+<function>XPeekIfEvent</function>
+copies the matched event into the client-supplied
+<structname>XEvent</structname>
+structure without removing the event from the queue.
+<function>XPeekIfEvent</function>
+flushes the output buffer if it blocks waiting for additional events.
+</para>
+</sect2>
+<sect2 id="Selecting_Events_Using_a_Window_or_Event_Mask">
+<title>Selecting Events Using a Window or Event Mask</title>
+<!-- .XS -->
+<!-- (SN Selecting Events Using a Window or Event Mask -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The functions discussed in this section let you select events by window
+or event types, allowing you to process events out of order.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To remove the next event that matches both a window and an event mask, use
+<function>XWindowEvent</function>.
+<indexterm significance="preferred"><primary>XWindowEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xwindowevent'>
+<funcprototype>
+ <funcdef><function>XWindowEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>long<parameter> event_mask</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Wi whose events you are interested in -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window (Wi.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event mask.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the matched event's associated structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XWindowEvent</function>
+function searches the event queue for an event that matches both the specified
+window and event mask.
+When it finds a match,
+<function>XWindowEvent</function>
+removes that event from the queue and copies it into the specified
+<structname>XEvent</structname>
+structure.
+The other events stored in the queue are not discarded.
+If a matching event is not in the queue,
+<function>XWindowEvent</function>
+flushes the output buffer and blocks until one is received.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To remove the next event that matches both a window and an event mask (if any),
+use
+<function>XCheckWindowEvent</function>.
+<indexterm><primary>XCheckWindowEvent</primary></indexterm>
+This function is similar to
+<function>XWindowEvent</function>
+except that it never blocks and it returns a
+<type>Bool</type>
+indicating if the event was returned.
+<indexterm significance="preferred"><primary>XCheckWindowEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcheckwindowevent'>
+<funcprototype>
+ <funcdef>Bool <function>XCheckWindowEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>long<parameter> event_mask</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Wi whose events you are interested in -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window (Wi.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event mask.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the matched event's associated structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCheckWindowEvent</function>
+function searches the event queue and then the events available
+on the server connection for the first event that matches the specified window
+and event mask.
+If it finds a match,
+<function>XCheckWindowEvent</function>
+removes that event, copies it into the specified
+<structname>XEvent</structname>
+structure, and returns
+<symbol>True</symbol>.
+The other events stored in the queue are not discarded.
+If the event you requested is not available,
+<function>XCheckWindowEvent</function>
+returns
+<symbol>False</symbol>,
+and the output buffer will have been flushed.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To remove the next event that matches an event mask, use
+<function>XMaskEvent</function>.
+<indexterm significance="preferred"><primary>XMaskEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmaskevent'>
+<funcprototype>
+ <funcdef><function>XMaskEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>long<parameter> event_mask</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event mask.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the matched event's associated structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XMaskEvent</function>
+function searches the event queue for the events associated with the
+specified mask.
+When it finds a match,
+<function>XMaskEvent</function>
+removes that event and copies it into the specified
+<structname>XEvent</structname>
+structure.
+The other events stored in the queue are not discarded.
+If the event you requested is not in the queue,
+<function>XMaskEvent</function>
+flushes the output buffer and blocks until one is received.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To return and remove the next event that matches an event mask (if any), use
+<function>XCheckMaskEvent</function>.
+This function is similar to
+<function>XMaskEvent</function>
+except that it never blocks and it returns a
+<type>Bool</type>
+indicating if the event was returned.
+<indexterm significance="preferred"><primary>XCheckMaskEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcheckmaskevent'>
+<funcprototype>
+ <funcdef>Bool <function>XCheckMaskEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>long<parameter> event_mask</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event mask.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the matched event's associated structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCheckMaskEvent</function>
+function searches the event queue and then any events available on the
+server connection for the first event that matches the specified mask.
+If it finds a match,
+<function>XCheckMaskEvent</function>
+removes that event, copies it into the specified
+<structname>XEvent</structname>
+structure, and returns
+<symbol>True</symbol>.
+The other events stored in the queue are not discarded.
+If the event you requested is not available,
+<function>XCheckMaskEvent</function>
+returns
+<symbol>False</symbol>,
+and the output buffer will have been flushed.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To return and remove the next event in the queue that matches an event type, use
+<function>XCheckTypedEvent</function>.
+<indexterm significance="preferred"><primary>XCheckTypedEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xchecktypedevent'>
+<funcprototype>
+ <funcdef>Bool <function>XCheckTypedEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> event_type</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_type</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event type to be compared.
+
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the matched event's associated structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCheckTypedEvent</function>
+function searches the event queue and then any events available
+on the server connection for the first event that matches the specified type.
+If it finds a match,
+<function>XCheckTypedEvent</function>
+removes that event, copies it into the specified
+<structname>XEvent</structname>
+structure, and returns
+<symbol>True</symbol>.
+The other events in the queue are not discarded.
+If the event is not available,
+<function>XCheckTypedEvent</function>
+returns
+<symbol>False</symbol>,
+and the output buffer will have been flushed.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To return and remove the next event in the queue that matches an event type
+and a window, use
+<function>XCheckTypedWindowEvent</function>.
+<indexterm significance="preferred"><primary>XCheckTypedWindowEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xchecktypedwindowevent'>
+<funcprototype>
+ <funcdef>Bool <function>XCheckTypedWindowEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>int<parameter> event_type</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_type</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event type to be compared.
+
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the matched event's associated structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCheckTypedWindowEvent</function>
+function searches the event queue and then any events available
+on the server connection for the first event that matches the specified
+type and window.
+If it finds a match,
+<function>XCheckTypedWindowEvent</function>
+removes the event from the queue, copies it into the specified
+<structname>XEvent</structname>
+structure, and returns
+<symbol>True</symbol>.
+The other events in the queue are not discarded.
+If the event is not available,
+<function>XCheckTypedWindowEvent</function>
+returns
+<symbol>False</symbol>,
+and the output buffer will have been flushed.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Putting_an_Event_Back_into_the_Queue">
+<title>Putting an Event Back into the Queue</title>
+<!-- .XS -->
+<!-- (SN Putting an Event Back into the Queue -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To push an event back into the event queue, use
+<function>XPutBackEvent</function>.
+<indexterm significance="preferred"><primary>XPutBackEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xputbackevent'>
+<funcprototype>
+ <funcdef><function>XPutBackEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XPutBackEvent</function>
+function pushes an event back onto the head of the display's event queue
+by copying the event into the queue.
+This can be useful if you read an event and then decide that you
+would rather deal with it later.
+There is no limit to the number of times in succession that you can call
+<function>XPutBackEvent</function>.
+</para>
+</sect1>
+<sect1 id="Sending_Events_to_Other_Applications">
+<title>Sending Events to Other Applications</title>
+<!-- .XS -->
+<!-- (SN Sending Events to Other Applications -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To send an event to a specified window, use
+<function>XSendEvent</function>.
+<indexterm><primary>XSendEvent</primary></indexterm>
+This function is often used in selection processing.
+For example, the owner of a selection should use
+<function>XSendEvent</function>
+to send a
+<symbol>SelectionNotify</symbol>
+event to a requestor when a selection has been converted
+and stored as a property.
+<indexterm significance="preferred"><primary>XSendEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsendevent'>
+<funcprototype>
+ <funcdef>Status <function>XSendEvent</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Bool<parameter> propagate</parameter></paramdef>
+ <paramdef>long<parameter> event_mask</parameter></paramdef>
+ <paramdef>XEvent<parameter> *event_send</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window the event is to be sent to, or
+<symbol>PointerWindow</symbol>,
+or
+<symbol>InputFocus</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>propagate</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event mask.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_send</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event that is to be sent.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSendEvent</function>
+function identifies the destination window,
+determines which clients should receive the specified events,
+and ignores any active grabs.
+This function requires you to pass an event mask.
+For a discussion of the valid event mask names,
+see section 10.3.
+This function uses the w argument to identify the destination window as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+If w is
+<symbol>PointerWindow</symbol>,
+the destination window is the window that contains the pointer.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If w is
+<symbol>InputFocus</symbol>
+and if the focus window contains the pointer,
+the destination window is the window that contains the pointer;
+otherwise, the destination window is the focus window.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+To determine which clients should receive the specified events,
+<function>XSendEvent</function>
+uses the propagate argument as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+If event_mask is the empty set,
+the event is sent to the client that created the destination window.
+If that client no longer exists,
+no event is sent.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If propagate is
+<symbol>False</symbol>,
+the event is sent to every client selecting on destination any of the event
+types in the event_mask argument.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If propagate is
+<symbol>True</symbol>
+and no clients have selected on destination any of
+the event types in event-mask, the destination is replaced with the
+closest ancestor of destination for which some client has selected a
+type in event-mask and for which no intervening window has that type in its
+do-not-propagate-mask.
+If no such window exists or if the window is
+an ancestor of the focus window and
+<symbol>InputFocus</symbol>
+was originally specified
+as the destination, the event is not sent to any clients.
+Otherwise, the event is reported to every client selecting on the final
+destination any of the types specified in event_mask.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The event in the
+<structname>XEvent</structname>
+structure must be one of the core events or one of the events
+defined by an extension (or a
+<errorname>BadValue</errorname>
+error results) so that the X server can correctly byte-swap
+the contents as necessary.
+The contents of the event are
+otherwise unaltered and unchecked by the X server except to force send_event to
+<symbol>True</symbol>
+in the forwarded event and to set the serial number in the event correctly;
+therefore these fields
+and the display field are ignored by
+<function>XSendEvent</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XSendEvent</function>
+returns zero if the conversion to wire protocol format failed
+and returns nonzero otherwise.
+</para>
+<para>
+<!-- .LP -->
+<function>XSendEvent</function>
+can generate
+<errorname>BadValue</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect1>
+<sect1 id="Getting_Pointer_Motion_History">
+<title>Getting Pointer Motion History</title>
+<!-- .XS -->
+<!-- (SN Getting Pointer Motion History -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Some X server implementations will maintain a more complete
+history of pointer motion than is reported by event notification.
+The pointer position at each pointer hardware interrupt may be
+stored in a buffer for later retrieval.
+This buffer is called the motion history buffer.
+For example, a few applications, such as paint programs,
+want to have a precise history of where the pointer
+traveled.
+However, this historical information is highly excessive for most applications.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To determine the approximate maximum number of elements in the motion buffer,
+use
+<function>XDisplayMotionBufferSize</function>.
+<indexterm significance="preferred"><primary>XDisplayMotionBufferSize</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdisplaymotionbuffersize'>
+<funcprototype>
+ <funcdef>unsigned <type>long</type></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The server may retain the recent history of the pointer motion
+and do so to a finer granularity than is reported by
+<symbol>MotionNotify</symbol>
+events.
+The
+<function>XGetMotionEvents</function>
+function makes this history available.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To get the motion history for a specified window and time, use
+<function>XGetMotionEvents</function>.
+<indexterm significance="preferred"><primary>XGetMotionEvents</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetmotionevents'>
+<funcprototype>
+ <funcdef>XTimeCoord *<function>XGetMotionEvents</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Timestart,<parameter> stop</parameter></paramdef>
+ <paramdef>int<parameter> *nevents_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>start</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>stop</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the time interval in which the events are returned from the motion
+history buffer.
+You can pass a timestamp or
+<symbol>CurrentTime</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nevents_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of events from the motion history buffer.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetMotionEvents</function>
+function returns all events in the motion history buffer that fall between the
+specified start and stop times, inclusive, and that have coordinates
+that lie within the specified window (including its borders) at its present
+placement.
+If the server does not support motion history,
+if the start time is later than the stop time,
+or if the start time is in the future,
+no events are returned;
+<function>XGetMotionEvents</function>
+returns NULL.
+If the stop time is in the future, it is equivalent to specifying
+<symbol>CurrentTime</symbol>.
+The return type for this function is a structure defined as follows:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XTimeCoord</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i -->
+<!-- .ta .5i -->
+typedef struct {
+ Time time;
+ short x, y;
+} XTimeCoord;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The time member is set to the time, in milliseconds.
+The x and y members are set to the coordinates of the pointer and
+are reported relative to the origin
+of the specified window.
+To free the data returned from this call, use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetMotionEvents</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Handling_Protocol_Errors">
+<title>Handling Protocol Errors</title>
+<!-- .XS -->
+<!-- (SN Handling Protocol Errors -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to enable or disable synchronization
+and to use the default error handlers.
+</para>
+<sect2 id="Enabling_or_Disabling_Synchronization">
+<title>Enabling or Disabling Synchronization</title>
+<!-- .XS -->
+<!-- (SN Enabling or Disabling Synchronization -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+When debugging X applications,
+it often is very convenient to require Xlib to behave synchronously
+so that errors are reported as they occur.
+The following function lets you disable or enable synchronous behavior.
+Note that graphics may occur 30 or more times more slowly when
+synchronization is enabled.
+<indexterm><primary>_Xdebug</primary></indexterm>
+On <acronym>POSIX</acronym>-conformant systems,
+there is also a global variable
+<varname>_Xdebug</varname>
+that, if set to nonzero before starting a program under a debugger, will force
+synchronous library behavior.
+</para>
+<para>
+<!-- .LP -->
+After completing their work,
+all Xlib functions that generate protocol requests call what is known as
+an after function.
+<function>XSetAfterFunction</function>
+sets which function is to be called.
+<indexterm significance="preferred"><primary>XSetAfterFunction</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetafterfunction'>
+<funcprototype>
+ <funcdef><type>int</type></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> (*procedure)()</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>procedure</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure to be called.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The specified procedure is called with only a display pointer.
+<function>XSetAfterFunction</function>
+returns the previous after function.
+</para>
+<para>
+<!-- .LP -->
+To enable or disable synchronization, use
+<function>XSynchronize</function>.
+<indexterm><primary>Debugging</primary><secondary>synchronous mode</secondary></indexterm>
+<indexterm significance="preferred"><primary>XSynchronize</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsynchronize'>
+<funcprototype>
+ <funcdef><type>int</type></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Bool<parameter> onoff</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>onoff</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value that indicates whether to enable
+or disable synchronization.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSynchronize</function>
+function returns
+the previous after function.
+If onoff is
+<symbol>True</symbol>,
+<function>XSynchronize</function>
+turns on synchronous behavior.
+If onoff is
+<symbol>False</symbol>,
+<function>XSynchronize</function>
+turns off synchronous behavior.
+</para>
+</sect2>
+<sect2 id="Using_the_Default_Error_Handlers">
+<title>Using the Default Error Handlers</title>
+<!-- .XS -->
+<!-- (SN Using the Default Error Handlers -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Debugging</primary><secondary>error handlers</secondary></indexterm>
+<indexterm><primary>Error</primary><secondary>handlers</secondary></indexterm>
+There are two default error handlers in Xlib:
+one to handle typically fatal conditions (for example,
+the connection to a display server dying because a machine crashed)
+and one to handle protocol errors from the X server.
+These error handlers can be changed to user-supplied routines if you
+prefer your own error handling and can be changed as often as you like.
+If either function is passed a NULL pointer, it will
+reinvoke the default handler.
+The action of the default handlers is to print an explanatory
+message and exit.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the error handler, use
+<function>XSetErrorHandler</function>.
+<indexterm significance="preferred"><primary>XSetErrorHandler</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xseterrorhandler'>
+<funcprototype>
+ <funcdef>int *<function>XSetErrorHandler</function></funcdef>
+ <paramdef>int <parameter> *handler</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>handler</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the program's supplied error handler.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Xlib generally calls the program's
+supplied error handler whenever an error is received.
+It is not called on
+<errorname>BadName</errorname>
+errors from
+<systemitem>OpenFont</systemitem>,
+<systemitem>LookupColor</systemitem>,
+or
+<systemitem>AllocNamedColor</systemitem>
+protocol requests or on
+<errorname>BadFont</errorname>
+errors from a
+<systemitem>QueryFont</systemitem>
+protocol request.
+These errors generally are reflected back to the program through the
+procedural interface.
+Because this condition is not assumed to be fatal,
+it is acceptable for your error handler to return;
+the returned value is ignored.
+However, the error handler should not
+call any functions (directly or indirectly) on the display
+that will generate protocol requests or that will look for input events.
+The previous error handler is returned.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XErrorEvent</structname>
+structure contains:
+<indexterm><primary>Debugging</primary><secondary>error event</secondary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XErrorEvent</primary></indexterm>
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ int type;
+ Display *display; /* Display the event was read from */
+ unsigned long serial; /* serial number of failed request */
+ unsigned char error_code; /* error code of failed request */
+ unsigned char request_code; /* Major op-code of failed request */
+ unsigned char minor_code; /* Minor op-code of failed request */
+ XID resourceid; /* resource id */
+} XErrorEvent;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<indexterm><primary>Serial Number</primary></indexterm>
+The serial member is the number of requests, starting from one,
+sent over the network connection since it was opened.
+It is the number that was the value of
+<function>NextRequest</function>
+immediately before the failing call was made.
+The request_code member is a protocol request
+of the procedure that failed, as defined in
+&lt; X11/Xproto.h .&gt;
+The following error codes can be returned by the functions described in this
+chapter:
+</para>
+<!-- .br -->
+<!-- .ne 13 -->
+<indexterm><primary>Debugging</primary><secondary>error numbers</secondary></indexterm>
+<indexterm><primary>Error</primary><secondary>codes</secondary></indexterm>
+<!-- .\".CP T 3 -->
+<!-- .\"Error Codes -->
+<indexterm significance="preferred"><primary>BadAccess</primary></indexterm>
+<indexterm significance="preferred"><primary>BadAlloc</primary></indexterm>
+<indexterm significance="preferred"><primary>BadAtom</primary></indexterm>
+<indexterm significance="preferred"><primary>BadColor</primary></indexterm>
+<indexterm significance="preferred"><primary>BadCursor</primary></indexterm>
+<indexterm significance="preferred"><primary>BadDrawable</primary></indexterm>
+<indexterm significance="preferred"><primary>BadFont</primary></indexterm>
+<indexterm significance="preferred"><primary>BadGC</primary></indexterm>
+<indexterm significance="preferred"><primary>BadIDChoice</primary></indexterm>
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <thead>
+ <row>
+ <entry>Error Code</entry>
+ <entry>Description</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><errorname>BadAccess</errorname></entry>
+ <entry>A client attempts to grab a key/button combination already grabbed
+ by another client.</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>A client attempts to free a colormap entry that it had not already allocated
+ or to free an entry in a colormap that was created with all entries writable.</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>A client attempts to store into a read-only or unallocated colormap entry.</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>A client attempts to modify the access control list from other than the local
+ (or otherwise authorized) host.</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>A client attempts to select an event type that another client
+ has already selected.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadAlloc</errorname></entry>
+ <entry>The server fails to allocate the requested resource.
+ Note that the explicit listing of
+ <errorname>BadAlloc</errorname>
+ errors in requests only covers allocation errors at a very coarse level
+ and is not intended to (nor can it in practice hope to) cover all cases of
+ a server running out of allocation space in the middle of service.
+ The semantics when a server runs out of allocation space are left unspecified,
+ but a server may generate a
+ <errorname>BadAlloc</errorname>
+ error on any request for this reason,
+ and clients should be prepared to receive such errors and handle or discard
+ them.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadAtom</errorname></entry>
+ <entry>A value for an atom argument does not name a defined atom.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadColor</errorname></entry>
+ <entry>A value for a colormap argument does not name a defined colormap.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadCursor</errorname></entry>
+ <entry>A value for a cursor argument does not name a defined cursor.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadDrawable</errorname></entry>
+ <entry>A value for a drawable argument does not name a defined window or pixmap.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadFont</errorname></entry>
+ <entry>A value for a font argument does not name a defined font (or, in some cases,
+ <type>GContext</type>).</entry>
+ </row>
+ <row>
+ <entry><errorname>BadGC</errorname></entry>
+ <entry>A value for a
+ <type>GContext</type>
+ argument does not name a defined
+ <type>GContext</type>.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadIDChoice</errorname></entry>
+ <entry>The value chosen for a resource identifier either is not included in the
+ range assigned to the client or is already in use.
+ Under normal circumstances,
+ this cannot occur and should be considered a server or Xlib error.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadImplementation</errorname></entry>
+ <entry>The server does not implement some aspect of the request.
+ A server that generates this error for a core request is deficient.
+ As such, this error is not listed for any of the requests,
+ but clients should be prepared to receive such errors
+ and handle or discard them.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadLength</errorname></entry>
+ <entry>The length of a request is shorter or longer than that required to
+ contain the arguments.
+ This is an internal Xlib or server error.</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>
+ The length of a request exceeds the maximum length accepted by the server.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadMatch</errorname></entry>
+ <entry>In a graphics request,
+ the root and depth of the graphics context do not match those of the drawable.</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>An <symbol>InputOnly</symbol> window is used as a drawable.</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>
+ Some argument or pair of arguments has the correct type and range,
+ but it fails to match in some other way required by the request.</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>An <symbol>InputOnly</symbol>
+ window lacks this attribute.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadName</errorname></entry>
+ <entry>A font or color of the specified name does not exist.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadPixmap</errorname></entry>
+ <entry>A value for a pixmap argument does not name a defined pixmap.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadRequest</errorname></entry>
+ <entry>The major or minor opcode does not specify a valid request.
+ This usually is an Xlib or server error.</entry>
+ </row>
+ <row>
+ <entry><errorname>BadValue</errorname></entry>
+ <entry>Some numeric value falls outside of the range of values accepted
+ by the request.
+ Unless a specific range is specified for an argument,
+ the full range defined by the argument's type is accepted.
+ Any argument defined as a set of alternatives typically can generate
+ this error (due to the encoding).</entry>
+ </row>
+ <row>
+ <entry><errorname>BadWindow</errorname></entry>
+ <entry>A value for a window argument does not name a defined window.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<indexterm significance="preferred"><primary>BadImplementation</primary></indexterm>
+<indexterm significance="preferred"><primary>BadLength</primary></indexterm>
+<indexterm significance="preferred"><primary>BadMatch</primary></indexterm>
+<indexterm significance="preferred"><primary>BadName</primary></indexterm>
+<indexterm significance="preferred"><primary>BadPixmap</primary></indexterm>
+<indexterm significance="preferred"><primary>BadRequest</primary></indexterm>
+<indexterm significance="preferred"><primary>BadValue</primary></indexterm>
+<indexterm significance="preferred"><primary>BadWindow</primary></indexterm>
+<!-- .NT Note -->
+
+<note>
+<para>
+The
+<errorname>BadAtom</errorname>,
+<errorname>BadColor</errorname>,
+<errorname>BadCursor</errorname>,
+<errorname>BadDrawable</errorname>,
+<errorname>BadFont</errorname>,
+<errorname>BadGC</errorname>,
+<errorname>BadPixmap</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors are also used when the argument type is extended by a set of
+fixed alternatives.
+</para>
+</note>
+
+<!-- .NE -->
+<!-- .sp -->
+<para>
+<!-- .LP -->
+To obtain textual descriptions of the specified error code, use
+<function>XGetErrorText</function>.
+<indexterm significance="preferred"><primary>XGetErrorText</primary></indexterm>
+<indexterm><primary>Debugging</primary><secondary>error message strings</secondary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgeterrortext'>
+<funcprototype>
+ <funcdef><function>XGetErrorText</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> code</parameter></paramdef>
+ <paramdef>char<parameter> *buffer_return</parameter></paramdef>
+ <paramdef>int<parameter> length</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>code</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the error code for which you want to obtain a description.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>buffer_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the error description.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>length</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the size of the buffer.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetErrorText</function>
+function copies a null-terminated string describing the specified error code
+into the specified buffer.
+The returned text is in the encoding of the current locale.
+It is recommended that you use this function to obtain an error description
+because extensions to Xlib may define their own error codes
+and error strings.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain error messages from the error database, use
+<function>XGetErrorDatabaseText</function>.
+<indexterm significance="preferred"><primary>XGetErrorDatabaseText</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgeterrordatabasetext'>
+<funcprototype>
+ <funcdef><function>XGetErrorDatabaseText</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char*name,<parameter> *message</parameter></paramdef>
+ <paramdef>char<parameter> *default_string</parameter></paramdef>
+ <paramdef>char<parameter> *buffer_return</parameter></paramdef>
+ <paramdef>int<parameter> length</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the name of the application.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>message</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the type of the error message.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>default_string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the default error message if none is found in the database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>buffer_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the error description.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>length</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the size of the buffer.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetErrorDatabaseText</function>
+function returns a null-terminated message
+(or the default message) from the error message
+database.
+Xlib uses this function internally to look up its error messages.
+The text in the default_string argument is assumed
+to be in the encoding of the current locale,
+and the text stored in the buffer_return argument
+is in the encoding of the current locale.
+</para>
+<para>
+<!-- .LP -->
+The name argument should generally be the name of your application.
+The message argument should indicate which type of error message you want.
+If the name and message are not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+Xlib uses three predefined ``application names'' to report errors.
+In these names,
+uppercase and lowercase matter.
+<variablelist>
+ <varlistentry>
+ <term>
+ XProtoError
+ </term>
+ <listitem>
+ <para>
+The protocol error number is used as a string for the message argument.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ XlibMessage
+ </term>
+ <listitem>
+ <para>
+These are the message strings that are used internally by the library.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ XRequest
+ </term>
+ <listitem>
+ <para>
+For a core protocol request,
+the major request protocol number is used for the message argument.
+For an extension request,
+the extension name (as given by
+<function>InitExtension</function>)
+followed by a period (.) and the minor request protocol number
+is used for the message argument.
+If no string is found in the error database,
+the default_string is returned to the buffer argument.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To report an error to the user when the requested display does not exist, use
+<function>XDisplayName</function>.
+<indexterm significance="preferred"><primary>XDisplayName</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdisplayname'>
+<funcprototype>
+ <funcdef>char *<function>XDisplayName</function></funcdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDisplayName</function>
+function returns the name of the display that
+<function>XOpenDisplay</function>
+would attempt to use.
+If a NULL string is specified,
+<function>XDisplayName</function>
+looks in the environment for the display and returns the display name that
+<function>XOpenDisplay</function>
+would attempt to use.
+This makes it easier to report to the user precisely which display the
+program attempted to open when the initial connection attempt failed.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To handle fatal I/O errors, use
+<function>XSetIOErrorHandler</function>.
+<indexterm significance="preferred"><primary>XSetIOErrorHandler</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetioerrorhandler'>
+<funcprototype>
+ <funcdef><type>int</type></funcdef>
+ <paramdef>int(*handler)(Display<parameter> *)</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>handler</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the program's supplied error handler.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetIOErrorHandler</function>
+sets the fatal I/O error handler.
+Xlib calls the program's supplied error handler if any sort of system call
+error occurs (for example, the connection to the server was lost).
+This is assumed to be a fatal condition,
+and the called routine should not return.
+If the I/O error handler does return,
+the client process exits.
+</para>
+<para>
+<!-- .LP -->
+Note that the previous error handler is returned.
+<!-- .bp -->
+
+</para>
+</sect2>
+</sect1>
+</chapter>
diff --git a/libX11/specs/libX11/CH12.xml b/libX11/specs/libX11/CH12.xml
index bfde8d927..2a688bdc5 100644
--- a/libX11/specs/libX11/CH12.xml
+++ b/libX11/specs/libX11/CH12.xml
@@ -1,3937 +1,3937 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<chapter id="input_device_functions">
-<title>Input Device Functions</title>
-
-<para>
-You can use the Xlib input device functions to:
-</para>
-
-<itemizedlist>
- <listitem><para>Grab the pointer and individual buttons on the pointer</para></listitem>
- <listitem><para>Grab the keyboard and individual keys on the keyboard</para></listitem>
- <listitem><para>Resume event processing</para></listitem>
- <listitem><para>Move the pointer</para></listitem>
- <listitem><para>Set the input focus</para></listitem>
- <listitem><para>Manipulate the keyboard and pointer settings</para></listitem>
- <listitem><para>Manipulate the keyboard encoding</para></listitem>
-</itemizedlist>
-
-<sect1 id="Pointer_Grabbing_">
-<title>Pointer Grabbing </title>
-<!-- .XS -->
-<!-- (SN Pointer Grabbing -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to control input from the pointer,
-which usually is a mouse.
-Usually, as soon as keyboard and mouse events occur,
-the X server delivers them to the appropriate client,
-which is determined by the window and input focus.
-The X server provides sufficient control over event delivery to
-allow window managers to support mouse ahead and various other
-styles of user interface.
-Many of these user interfaces depend on synchronous delivery of events.
-The delivery of pointer and keyboard events can be controlled
-independently.
-</para>
-<para>
-<!-- .LP -->
-When mouse buttons or keyboard keys are grabbed, events
-will be sent to the grabbing client rather than the normal
-client who would have received the event.
-If the keyboard or pointer is in asynchronous mode,
-further mouse and keyboard events will continue to be processed.
-If the keyboard or pointer is in synchronous mode, no
-further events are processed until the grabbing client
-allows them (see
-<function>XAllowEvents</function>).
-The keyboard or pointer is considered frozen during this
-interval.
-The event that triggered the grab can also be replayed.
-</para>
-<para>
-<!-- .LP -->
-Note that the logical state of a device (as seen by client applications)
-may lag the physical state if device event processing is frozen.
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>Active grab</primary></indexterm>
-There are two kinds of grabs:
-active and passive.
-An active grab occurs when a single client grabs the keyboard and/or pointer
-explicitly (see
-<function>XGrabPointer</function>
-and
-<function>XGrabKeyboard</function>).
-<indexterm><primary>Passive grab</primary></indexterm>
-A passive grab occurs when clients grab a particular keyboard key
-or pointer button in a window,
-and the grab will activate when the key or button is actually pressed.
-Passive grabs are convenient for implementing reliable pop-up menus.
-For example, you can guarantee that the pop-up is mapped
-before the up pointer button event occurs by
-grabbing a button requesting synchronous behavior.
-The down event will trigger the grab and freeze further
-processing of pointer events until you have the chance to
-map the pop-up window.
-You can then allow further event processing.
-The up event will then be correctly processed relative to the
-pop-up window.
-</para>
-<para>
-<!-- .LP -->
-For many operations,
-there are functions that take a time argument.
-The X server includes a timestamp in various events.
-One special time, called
-<indexterm significance="preferred"><primary>CurrentTime</primary></indexterm>
-<indexterm significance="preferred"><primary>Time</primary></indexterm>
-<symbol>CurrentTime</symbol>,
-represents the current server time.
-The X server maintains the time when the input focus was last changed,
-when the keyboard was last grabbed,
-when the pointer was last grabbed,
-or when a selection was last changed.
-Your
-application may be slow reacting to an event.
-You often need some way to specify that your
-request should not occur if another application has in the meanwhile
-taken control of the keyboard, pointer, or selection.
-By providing the timestamp from the event in the request,
-you can arrange that the operation not take effect
-if someone else has performed an operation in the meanwhile.
-</para>
-<para>
-<!-- .LP -->
-A timestamp is a time value, expressed in milliseconds.
-It typically is the time since the last server reset.
-Timestamp values wrap around (after about 49.7 days).
-The server, given its current time is represented by timestamp T,
-always interprets timestamps from clients by treating half of the timestamp
-space as being later in time than T.
-One timestamp value, named
-<symbol>CurrentTime</symbol>,
-is never generated by the server.
-This value is reserved for use in requests to represent the current server time.
-</para>
-<para>
-<!-- .LP -->
-For many functions in this section,
-you pass pointer event mask bits.
-The valid pointer event mask bits are:
-<symbol>ButtonPressMask</symbol>,
-<symbol>ButtonReleaseMask</symbol>,
-<symbol>EnterWindowMask</symbol>,
-<symbol>LeaveWindowMask</symbol>,
-<symbol>PointerMotionMask</symbol>,
-<symbol>PointerMotionHintMask</symbol>,
-<symbol>Button1MotionMask</symbol>,
-<symbol>Button2MotionMask</symbol>,
-<symbol>Button3MotionMask</symbol>,
-<symbol>Button4MotionMask</symbol>,
-<symbol>Button5MotionMask</symbol>,
-<symbol>ButtonMotionMask</symbol>,
-and
-<symbol>KeymapStateMask</symbol>.
-For other functions in this section,
-you pass keymask bits.
-The valid keymask bits are:
-<symbol>ShiftMask</symbol>,
-<symbol>LockMask</symbol>,
-<symbol>ControlMask</symbol>,
-<symbol>Mod1Mask</symbol>,
-<symbol>Mod2Mask</symbol>,
-<symbol>Mod3Mask</symbol>,
-<symbol>Mod4Mask</symbol>,
-and
-<symbol>Mod5Mask</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To grab the pointer, use
-<function>XGrabPointer</function>.
-<indexterm><primary>Grabbing</primary><secondary>pointer</secondary></indexterm>
-<indexterm><primary>Pointer</primary><secondary>grabbing</secondary></indexterm>
-<indexterm significance="preferred"><primary>XGrabPointer</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XGrabPointer</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> grab_window</parameter></paramdef>
- <paramdef>Bool<parameter> owner_events</parameter></paramdef>
- <paramdef>unsignedint<parameter> event_mask</parameter></paramdef>
- <paramdef>intpointer_mode,<parameter> keyboard_mode</parameter></paramdef>
- <paramdef>Window<parameter> confine_to</parameter></paramdef>
- <paramdef>Cursor<parameter> cursor</parameter></paramdef>
- <paramdef>Time<parameter> time</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>grab_window</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the grab window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>owner_events</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value that indicates whether the pointer
-events are to be reported as usual or reported with respect to the grab window
-if selected by the event mask.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which pointer events are reported to the client.
-The mask is the bitwise inclusive OR of the valid pointer event mask bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pointer_mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies further processing of pointer events.
-You can pass
-<symbol>GrabModeSync</symbol>
-or
-<symbol>GrabModeAsync</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keyboard_mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies further processing of keyboard events.
-You can pass
-<symbol>GrabModeSync</symbol>
-or
-<symbol>GrabModeAsync</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>confine_to</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window to confine the pointer in or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>cursor</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the cursor that is to be displayed during the grab or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>time</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the time.
-You can pass either a timestamp or
-<symbol>CurrentTime</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGrabPointer</function>
-function actively grabs control of the pointer and returns
-<symbol>GrabSuccess</symbol>
-if the grab was successful.
-Further pointer events are reported only to the grabbing client.
-<function>XGrabPointer</function>
-overrides any active pointer grab by this client.
-If owner_events is
-<symbol>False</symbol>,
-all generated pointer events
-are reported with respect to grab_window and are reported only if
-selected by event_mask.
-If owner_events is
-<symbol>True</symbol>
-and if a generated
-pointer event would normally be reported to this client,
-it is reported as usual.
-Otherwise, the event is reported with respect to the
-grab_window and is reported only if selected by event_mask.
-For either value of owner_events, unreported events are discarded.
-</para>
-<para>
-<!-- .LP -->
-If the pointer_mode is
-<symbol>GrabModeAsync</symbol>,
-pointer event processing continues as usual.
-If the pointer is currently frozen by this client,
-the processing of events for the pointer is resumed.
-If the pointer_mode is
-<symbol>GrabModeSync</symbol>,
-the state of the pointer, as seen by
-client applications,
-appears to freeze, and the X server generates no further pointer events
-until the grabbing client calls
-<function>XAllowEvents</function>
-or until the pointer grab is released.
-Actual pointer changes are not lost while the pointer is frozen;
-they are simply queued in the server for later processing.
-</para>
-<para>
-<!-- .LP -->
-If the keyboard_mode is
-<symbol>GrabModeAsync</symbol>,
-keyboard event processing is unaffected by activation of the grab.
-If the keyboard_mode is
-<symbol>GrabModeSync</symbol>,
-the state of the keyboard, as seen by
-client applications,
-appears to freeze, and the X server generates no further keyboard events
-until the grabbing client calls
-<function>XAllowEvents</function>
-or until the pointer grab is released.
-Actual keyboard changes are not lost while the pointer is frozen;
-they are simply queued in the server for later processing.
-</para>
-<para>
-<!-- .LP -->
-If a cursor is specified, it is displayed regardless of what
-window the pointer is in.
-If
-<symbol>None</symbol>
-is specified,
-the normal cursor for that window is displayed
-when the pointer is in grab_window or one of its subwindows;
-otherwise, the cursor for grab_window is displayed.
-</para>
-<para>
-<!-- .LP -->
-If a confine_to window is specified,
-the pointer is restricted to stay contained in that window.
-The confine_to window need have no relationship to the grab_window.
-If the pointer is not initially in the confine_to window,
-it is warped automatically to the closest edge
-just before the grab activates and enter/leave events are generated as usual.
-If the confine_to window is subsequently reconfigured,
-the pointer is warped automatically, as necessary,
-to keep it contained in the window.
-</para>
-<para>
-<!-- .LP -->
-The time argument allows you to avoid certain circumstances that come up
-if applications take a long time to respond or if there are long network
-delays.
-Consider a situation where you have two applications, both
-of which normally grab the pointer when clicked on.
-If both applications specify the timestamp from the event,
-the second application may wake up faster and successfully grab the pointer
-before the first application.
-The first application then will get an indication that the other application
-grabbed the pointer before its request was processed.
-</para>
-<para>
-<!-- .LP -->
-<function>XGrabPointer</function>
-generates
-<symbol>EnterNotify</symbol>
-and
-<symbol>LeaveNotify</symbol>
-events.
-</para>
-<para>
-<!-- .LP -->
-Either if grab_window or confine_to window is not viewable
-or if the confine_to window lies completely outside the boundaries of the root
-window,
-<function>XGrabPointer</function>
-fails and returns
-<symbol>GrabNotViewable</symbol>.
-If the pointer is actively grabbed by some other client,
-it fails and returns
-<symbol>AlreadyGrabbed</symbol>.
-If the pointer is frozen by an active grab of another client,
-it fails and returns
-<symbol>GrabFrozen</symbol>.
-If the specified time is earlier than the last-pointer-grab time or later
-than the current X server time, it fails and returns
-<symbol>GrabInvalidTime</symbol>.
-Otherwise, the last-pointer-grab time is set to the specified time
-(<symbol>CurrentTime</symbol>
-is replaced by the current X server time).
-</para>
-<para>
-<!-- .LP -->
-<function>XGrabPointer</function>
-can generate
-<errorname>BadCursor</errorname>,
-<errorname>BadValue</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To ungrab the pointer, use
-<function>XUngrabPointer</function>.
-<indexterm><primary>Ungrabbing</primary><secondary>pointer</secondary></indexterm>
-<indexterm><primary>Pointer</primary><secondary>ungrabbing</secondary></indexterm>
-<indexterm significance="preferred"><primary>XUngrabPointer</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XUngrabPointer</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Time<parameter> time</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>time</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the time.
-You can pass either a timestamp or
-<symbol>CurrentTime</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUngrabPointer</function>
-function releases the pointer and any queued events
-if this client has actively grabbed the pointer from
-<function>XGrabPointer</function>,
-<function>XGrabButton</function>,
-or from a normal button press.
-<function>XUngrabPointer</function>
-does not release the pointer if the specified
-time is earlier than the last-pointer-grab time or is later than the
-current X server time.
-It also generates
-<symbol>EnterNotify</symbol>
-and
-<symbol>LeaveNotify</symbol>
-events.
-The X server performs an
-<systemitem>UngrabPointer</systemitem>
-request automatically if the event window or confine_to window
-for an active pointer grab becomes not viewable
-or if window reconfiguration causes the confine_to window to lie completely
-outside the boundaries of the root window.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To change an active pointer grab, use
-<function>XChangeActivePointerGrab</function>.
-<indexterm><primary>Pointer</primary><secondary>grabbing</secondary></indexterm>
-<indexterm ><primary>Changing</primary><secondary>pointer grab</secondary></indexterm>
-<indexterm significance="preferred"><primary>XChangeActivePointerGrab</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XChangeActivePointerGrab</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>unsignedint<parameter> event_mask</parameter></paramdef>
- <paramdef>Cursor<parameter> cursor</parameter></paramdef>
- <paramdef>Time<parameter> time</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which pointer events are reported to the client.
-The mask is the bitwise inclusive OR of the valid pointer event mask bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>cursor</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the cursor that is to be displayed or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>time</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the time.
-You can pass either a timestamp or
-<symbol>CurrentTime</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XChangeActivePointerGrab</function>
-function changes the specified dynamic parameters if the pointer is actively
-grabbed by the client and if the specified time is no earlier than the
-last-pointer-grab time and no later than the current X server time.
-This function has no effect on the passive parameters of an
-<function>XGrabButton</function>.
-The interpretation of event_mask and cursor is the same as described in
-<function>XGrabPointer</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XChangeActivePointerGrab</function>
-can generate
-<errorname>BadCursor</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To grab a pointer button, use
-<function>XGrabButton</function>.
-<indexterm><primary>Grabbing</primary><secondary>buttons</secondary></indexterm>
-<indexterm><primary>Button</primary><secondary>grabbing</secondary></indexterm>
-<indexterm significance="preferred"><primary>XGrabButton</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XGrabButton</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>unsignedint<parameter> button</parameter></paramdef>
- <paramdef>unsignedint<parameter> modifiers</parameter></paramdef>
- <paramdef>Window<parameter> grab_window</parameter></paramdef>
- <paramdef>Bool<parameter> owner_events</parameter></paramdef>
- <paramdef>unsignedint<parameter> event_mask</parameter></paramdef>
- <paramdef>intpointer_mode,<parameter> keyboard_mode</parameter></paramdef>
- <paramdef>Window<parameter> confine_to</parameter></paramdef>
- <paramdef>Cursor<parameter> cursor</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Bu grabbed -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>button</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the pointer button that is to be (Bu or
-<symbol>AnyButton</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>modifiers</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the set of keymasks or
-<symbol>AnyModifier</symbol>.
-The mask is the bitwise inclusive OR of the valid keymask bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>grab_window</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the grab window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>owner_events</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value that indicates whether the pointer
-events are to be reported as usual or reported with respect to the grab window
-if selected by the event mask.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which pointer events are reported to the client.
-The mask is the bitwise inclusive OR of the valid pointer event mask bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pointer_mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies further processing of pointer events.
-You can pass
-<symbol>GrabModeSync</symbol>
-or
-<symbol>GrabModeAsync</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keyboard_mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies further processing of keyboard events.
-You can pass
-<symbol>GrabModeSync</symbol>
-or
-<symbol>GrabModeAsync</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>confine_to</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window to confine the pointer in or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>cursor</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the cursor that is to be displayed or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGrabButton</function>
-function establishes a passive grab.
-In the future,
-the pointer is actively grabbed (as for
-<function>XGrabPointer</function>),
-the last-pointer-grab time is set to the time at which the button was pressed
-(as transmitted in the
-<symbol>ButtonPress</symbol>
-event), and the
-<symbol>ButtonPress</symbol>
-event is reported if all of the following conditions are true:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The pointer is not grabbed, and the specified button is logically pressed
-when the specified modifier keys are logically down,
-and no other buttons or modifier keys are logically down.
- </para>
- </listitem>
- <listitem>
- <para>
-The grab_window contains the pointer.
- </para>
- </listitem>
- <listitem>
- <para>
-The confine_to window (if any) is viewable.
- </para>
- </listitem>
- <listitem>
- <para>
-A passive grab on the same button/key combination does not exist
-on any ancestor of grab_window.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The interpretation of the remaining arguments is as for
-<function>XGrabPointer</function>.
-The active grab is terminated automatically when the logical state of the
-pointer has all buttons released
-(independent of the state of the logical modifier keys).
-</para>
-<para>
-<!-- .LP -->
-Note that the logical state of a device (as seen by client applications)
-may lag the physical state if device event processing is frozen.
-</para>
-<para>
-<!-- .LP -->
-This request overrides all previous grabs by the same client on the same
-button/key combinations on the same window.
-A modifiers of
-<symbol>AnyModifier</symbol>
-is equivalent to issuing the grab request for all
-possible modifier combinations (including the combination of no modifiers).
-It is not required that all modifiers specified have currently assigned
-KeyCodes.
-A button of
-<symbol>AnyButton</symbol>
-is equivalent to
-issuing the request for all possible buttons.
-Otherwise, it is not required that the specified button currently be assigned
-to a physical button.
-</para>
-<para>
-<!-- .LP -->
-If some other client has already issued an
-<function>XGrabButton</function>
-with the same button/key combination on the same window, a
-<errorname>BadAccess</errorname>
-error results.
-When using
-<symbol>AnyModifier</symbol>
-or
-<symbol>AnyButton</symbol>,
-the request fails completely,
-and a
-<errorname>BadAccess</errorname>
-error results (no grabs are
-established) if there is a conflicting grab for any combination.
-<function>XGrabButton</function>
-has no effect on an active grab.
-</para>
-<para>
-<!-- .LP -->
-<function>XGrabButton</function>
-can generate
-<errorname>BadCursor</errorname>,
-<errorname>BadValue</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To ungrab a pointer button, use
-<function>XUngrabButton</function>.
-<indexterm><primary>Ungrabbing</primary><secondary>buttons</secondary></indexterm>
-<indexterm><primary>Button</primary><secondary>ungrabbing</secondary></indexterm>
-<indexterm significance="preferred"><primary>XUngrabButton</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XUngrabButton</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>unsignedint<parameter> button</parameter></paramdef>
- <paramdef>unsignedint<parameter> modifiers</parameter></paramdef>
- <paramdef>Window<parameter> grab_window</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Bu released -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>button</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the pointer button that is to be (Bu or
-<symbol>AnyButton</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>modifiers</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the set of keymasks or
-<symbol>AnyModifier</symbol>.
-The mask is the bitwise inclusive OR of the valid keymask bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>grab_window</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the grab window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUngrabButton</function>
-function releases the passive button/key combination on the specified window if
-it was grabbed by this client.
-A modifiers of
-<symbol>AnyModifier</symbol>
-is
-equivalent to issuing
-the ungrab request for all possible modifier combinations, including
-the combination of no modifiers.
-A button of
-<symbol>AnyButton</symbol>
-is equivalent to issuing the
-request for all possible buttons.
-<function>XUngrabButton</function>
-has no effect on an active grab.
-</para>
-<para>
-<!-- .LP -->
-<function>XUngrabButton</function>
-can generate
-<errorname>BadValue</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect1>
-<sect1 id="Keyboard_Grabbing_">
-<title>Keyboard Grabbing </title>
-<!-- .XS -->
-<!-- (SN Keyboard Grabbing -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to grab or ungrab the keyboard
-as well as allow events.
-</para>
-<para>
-<!-- .LP -->
-For many functions in this section,
-you pass keymask bits.
-The valid keymask bits are:
-<symbol>ShiftMask</symbol>,
-<symbol>LockMask</symbol>,
-<symbol>ControlMask</symbol>,
-<symbol>Mod1Mask</symbol>,
-<symbol>Mod2Mask</symbol>,
-<symbol>Mod3Mask</symbol>,
-<symbol>Mod4Mask</symbol>,
-and
-<symbol>Mod5Mask</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To grab the keyboard, use
-<function>XGrabKeyboard</function>.
-<indexterm><primary>Keyboard</primary><secondary>grabbing</secondary></indexterm>
-<indexterm><primary>Grabbing</primary><secondary>keyboard</secondary></indexterm>
-<indexterm significance="preferred"><primary>XGrabKeyboard</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XGrabKeyboard</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> grab_window</parameter></paramdef>
- <paramdef>Bool<parameter> owner_events</parameter></paramdef>
- <paramdef>intpointer_mode,<parameter> keyboard_mode</parameter></paramdef>
- <paramdef>Time<parameter> time</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>grab_window</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the grab window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>owner_events</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value that indicates whether the keyboard events
-are to be reported as usual.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pointer_mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies further processing of pointer events.
-You can pass
-<symbol>GrabModeSync</symbol>
-or
-<symbol>GrabModeAsync</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keyboard_mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies further processing of keyboard events.
-You can pass
-<symbol>GrabModeSync</symbol>
-or
-<symbol>GrabModeAsync</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>time</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the time.
-You can pass either a timestamp or
-<symbol>CurrentTime</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGrabKeyboard</function>
-function actively grabs control of the keyboard and generates
-<symbol>FocusIn</symbol>
-and
-<symbol>FocusOut</symbol>
-events.
-Further key events are reported only to the
-grabbing client.
-<function>XGrabKeyboard</function>
-overrides any active keyboard grab by this client.
-If owner_events is
-<symbol>False</symbol>,
-all generated key events are reported with
-respect to grab_window.
-If owner_events is
-<symbol>True</symbol>
-and if a generated
-key event would normally be reported to this client, it is reported
-normally; otherwise, the event is reported with respect to the
-grab_window.
-Both
-<symbol>KeyPress</symbol>
-and
-<symbol>KeyRelease</symbol>
-events are always reported,
-independent of any event selection made by the client.
-</para>
-<para>
-<!-- .LP -->
-If the keyboard_mode argument is
-<symbol>GrabModeAsync</symbol>,
-keyboard event processing continues
-as usual.
-If the keyboard is currently frozen by this client,
-then processing of keyboard events is resumed.
-If the keyboard_mode argument is
-<symbol>GrabModeSync</symbol>,
-the state of the keyboard (as seen by client applications) appears to freeze,
-and the X server generates no further keyboard events until the
-grabbing client issues a releasing
-<function>XAllowEvents</function>
-call or until the keyboard grab is released.
-Actual keyboard changes are not lost while the keyboard is frozen;
-they are simply queued in the server for later processing.
-</para>
-<para>
-<!-- .LP -->
-If pointer_mode is
-<symbol>GrabModeAsync</symbol>,
-pointer event processing is unaffected
-by activation of the grab.
-If pointer_mode is
-<symbol>GrabModeSync</symbol>,
-the state of the pointer (as seen by client applications) appears to freeze,
-and the X server generates no further pointer events
-until the grabbing client issues a releasing
-<function>XAllowEvents</function>
-call or until the keyboard grab is released.
-Actual pointer changes are not lost while the pointer is frozen;
-they are simply queued in the server for later processing.
-</para>
-<para>
-<!-- .LP -->
-If the keyboard is actively grabbed by some other client,
-<function>XGrabKeyboard</function>
-fails and returns
-<symbol>AlreadyGrabbed</symbol>.
-If grab_window is not viewable,
-it fails and returns
-<symbol>GrabNotViewable</symbol>.
-If the keyboard is frozen by an active grab of another client,
-it fails and returns
-<symbol>GrabFrozen</symbol>.
-If the specified time is earlier than the last-keyboard-grab time
-or later than the current X server time,
-it fails and returns
-<symbol>GrabInvalidTime</symbol>.
-Otherwise, the last-keyboard-grab time is set to the specified time
-(<symbol>CurrentTime</symbol>
-is replaced by the current X server time).
-</para>
-<para>
-<!-- .LP -->
-<function>XGrabKeyboard</function>
-can generate
-<errorname>BadValue</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To ungrab the keyboard, use
-<function>XUngrabKeyboard</function>.
-<indexterm><primary>Keyboard</primary><secondary>ungrabbing</secondary></indexterm>
-<indexterm><primary>Ungrabbing</primary><secondary>keyboard</secondary></indexterm>
-<indexterm significance="preferred"><primary>XUngrabKeyboard</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XUngrabKeyboard</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Time<parameter> time</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>time</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the time.
-You can pass either a timestamp or
-<symbol>CurrentTime</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUngrabKeyboard</function>
-function
-releases the keyboard and any queued events if this client has it actively grabbed from
-either
-<function>XGrabKeyboard</function>
-or
-<function>XGrabKey</function>.
-<function>XUngrabKeyboard</function>
-does not release the keyboard and any queued events
-if the specified time is earlier than
-the last-keyboard-grab time or is later than the current X server time.
-It also generates
-<symbol>FocusIn</symbol>
-and
-<symbol>FocusOut</symbol>
-events.
-The X server automatically performs an
-<systemitem>UngrabKeyboard</systemitem>
-request if the event window for an
-active keyboard grab becomes not viewable.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To passively grab a single key of the keyboard, use
-<function>XGrabKey</function>.
-<indexterm><primary>Key</primary><secondary>grabbing</secondary></indexterm>
-<indexterm><primary>Grabbing</primary><secondary>keys</secondary></indexterm>
-<indexterm significance="preferred"><primary>XGrabKey</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XGrabKey</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> keycode</parameter></paramdef>
- <paramdef>unsignedint<parameter> modifiers</parameter></paramdef>
- <paramdef>Window<parameter> grab_window</parameter></paramdef>
- <paramdef>Bool<parameter> owner_events</parameter></paramdef>
- <paramdef>intpointer_mode,<parameter> keyboard_mode</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keycode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeyCode or
-<symbol>AnyKey</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>modifiers</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the set of keymasks or
-<symbol>AnyModifier</symbol>.
-The mask is the bitwise inclusive OR of the valid keymask bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>grab_window</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the grab window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>owner_events</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value that indicates whether the keyboard events
-are to be reported as usual.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pointer_mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies further processing of pointer events.
-You can pass
-<symbol>GrabModeSync</symbol>
-or
-<symbol>GrabModeAsync</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keyboard_mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies further processing of keyboard events.
-You can pass
-<symbol>GrabModeSync</symbol>
-or
-<symbol>GrabModeAsync</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGrabKey</function>
-function establishes a passive grab on the keyboard.
-In the future,
-the keyboard is actively grabbed (as for
-<function>XGrabKeyboard</function>),
-the last-keyboard-grab time is set to the time at which the key was pressed
-(as transmitted in the
-<symbol>KeyPress</symbol>
-event), and the
-<symbol>KeyPress</symbol>
-event is reported if all of the following conditions are true:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The keyboard is not grabbed and the specified key
-(which can itself be a modifier key) is logically pressed
-when the specified modifier keys are logically down,
-and no other modifier keys are logically down.
- </para>
- </listitem>
- <listitem>
- <para>
-Either the grab_window is an ancestor of (or is) the focus window,
-or the grab_window is a descendant of the focus window and contains the pointer.
- </para>
- </listitem>
- <listitem>
- <para>
-A passive grab on the same key combination does not exist
-on any ancestor of grab_window.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The interpretation of the remaining arguments is as for
-<function>XGrabKeyboard</function>.
-The active grab is terminated automatically when the logical state of the
-keyboard has the specified key released
-(independent of the logical state of the modifier keys).
-</para>
-<para>
-<!-- .LP -->
-Note that the logical state of a device (as seen by client applications)
-may lag the physical state if device event processing is frozen.
-</para>
-<para>
-<!-- .LP -->
-A modifiers argument of
-<symbol>AnyModifier</symbol>
-is equivalent to issuing the request for all
-possible modifier combinations (including the combination of no
-modifiers).
-It is not required that all modifiers specified have
-currently assigned KeyCodes.
-A keycode argument of
-<symbol>AnyKey</symbol>
-is equivalent to issuing
-the request for all possible KeyCodes.
-Otherwise, the specified keycode must be in
-the range specified by min_keycode and max_keycode in the connection
-setup,
-or a
-<errorname>BadValue</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-If some other client has issued a
-<function>XGrabKey</function>
-with the same key combination on the same window, a
-<errorname>BadAccess</errorname>
-error results.
-When using
-<symbol>AnyModifier</symbol>
-or
-<symbol>AnyKey</symbol>,
-the request fails completely,
-and a
-<errorname>BadAccess</errorname>
-error results (no grabs are established)
-if there is a conflicting grab for any combination.
-</para>
-<para>
-<!-- .LP -->
-<function>XGrabKey</function>
-can generate
-<errorname>BadAccess</errorname>,
-<errorname>BadValue</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To ungrab a key, use
-<function>XUngrabKey</function>.
-<indexterm><primary>Key</primary><secondary>ungrabbing</secondary></indexterm>
-<indexterm><primary>Ungrabbing</primary><secondary>keys</secondary></indexterm>
-<indexterm significance="preferred"><primary>XUngrabKey</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XUngrabKey</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> keycode</parameter></paramdef>
- <paramdef>unsignedint<parameter> modifiers</parameter></paramdef>
- <paramdef>Window<parameter> grab_window</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keycode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeyCode or
-<symbol>AnyKey</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>modifiers</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the set of keymasks or
-<symbol>AnyModifier</symbol>.
-The mask is the bitwise inclusive OR of the valid keymask bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>grab_window</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the grab window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUngrabKey</function>
-function releases the key combination on the specified window if it was grabbed
-by this client.
-It has no effect on an active grab.
-A modifiers of
-<symbol>AnyModifier</symbol>
-is equivalent to issuing
-the request for all possible modifier combinations
-(including the combination of no modifiers).
-A keycode argument of
-<symbol>AnyKey</symbol>
-is equivalent to issuing the request for all possible key codes.
-</para>
-<para>
-<!-- .LP -->
-<function>XUngrabKey</function>
-can generate
-<errorname>BadValue</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect1>
-<sect1 id="Resuming_Event_Processing">
-<title>Resuming Event Processing</title>
-<!-- .XS -->
-<!-- (SN Resuming Event Processing -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The previous sections discussed grab mechanisms with which processing
-of events by the server can be temporarily suspended. This section
-describes the mechanism for resuming event processing.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To allow further events to be processed when the device has been frozen, use
-<function>XAllowEvents</function>.
-<indexterm significance="preferred"><primary>XAllowEvents</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XAllowEvents</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> event_mode</parameter></paramdef>
- <paramdef>Time<parameter> time</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the event mode.
-You can pass
-<symbol>AsyncPointer</symbol>,
-<symbol>SyncPointer</symbol>,
-<symbol>AsyncKeyboard</symbol>,
-<symbol>SyncKeyboard</symbol>,
-<symbol>ReplayPointer</symbol>,
-<symbol>ReplayKeyboard</symbol>,
-<symbol>AsyncBoth</symbol>,
-or
-<symbol>SyncBoth</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>time</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the time.
-You can pass either a timestamp or
-<symbol>CurrentTime</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAllowEvents</function>
-function releases some queued events if the client has caused a device
-to freeze.
-It has no effect if the specified time is earlier than the last-grab
-time of the most recent active grab for the client or if the specified time
-is later than the current X server time.
-Depending on the event_mode argument, the following occurs:
-</para>
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <tbody>
- <row>
- <entry><symbol>AsyncPointer</symbol></entry>
- <entry>If the pointer is frozen by the client,
- pointer event processing continues as usual.
- If the pointer is frozen twice by the client on behalf of two separate grabs,
- <symbol>AsyncPointer</symbol>
- thaws for both.
- <symbol>AsyncPointer</symbol>
- has no effect if the pointer is not frozen by the client,
- but the pointer need not be grabbed by the client.</entry>
- </row>
- <row>
- <entry><symbol>SyncPointer</symbol></entry>
- <entry>If the pointer is frozen and actively grabbed by the client,
- pointer event processing continues as usual until the next
- <symbol>ButtonPress</symbol>
- or
- <symbol>ButtonRelease</symbol>
- event is reported to the client.
- At this time,
- the pointer again appears to freeze.
- However, if the reported event causes the pointer grab to be released,
- the pointer does not freeze.
- <symbol>SyncPointer</symbol>
- has no effect if the pointer is not frozen by the client
- or if the pointer is not grabbed by the client.</entry>
- </row>
- <row>
- <entry><symbol>ReplayPointer</symbol></entry>
- <entry>If the pointer is actively grabbed by the client and is frozen as the result of
- an event having been sent to the client (either from the activation of an
- <function>XGrabButton</function>
- or from a previous
- <function>XAllowEvents</function>
- with mode
- <symbol>SyncPointer</symbol>
- but not from an
- <function>XGrabPointer</function>),
- the pointer grab is released and that event is completely reprocessed.
- This time, however, the function ignores any passive grabs at or above
- (toward the root of) the grab_window of the grab just released.
- The request has no effect if the pointer is not grabbed by the client
- or if the pointer is not frozen as the result of an event.</entry>
- </row>
- <row>
- <entry><symbol>AsyncKeyboard</symbol></entry>
- <entry>If the keyboard is frozen by the client,
- keyboard event processing continues as usual.
- If the keyboard is frozen twice by the client on behalf of two separate grabs,
- <symbol>AsyncKeyboard</symbol>
- thaws for both.
- <symbol>AsyncKeyboard</symbol>
- has no effect if the keyboard is not frozen by the client,
- but the keyboard need not be grabbed by the client.</entry>
- </row>
- <row>
- <entry><symbol>SyncKeyboard</symbol></entry>
- <entry>If the keyboard is frozen and actively grabbed by the client,
- keyboard event processing continues as usual until the next
- <symbol>KeyPress</symbol>
- or
- <symbol>KeyRelease</symbol>
- event is reported to the client.
- At this time,
- the keyboard again appears to freeze.
- However, if the reported event causes the keyboard grab to be released,
- the keyboard does not freeze.
- <symbol>SyncKeyboard</symbol>
- has no effect if the keyboard is not frozen by the client
- or if the keyboard is not grabbed by the client.</entry>
- </row>
- <row>
- <entry><symbol>ReplayKeyboard</symbol></entry>
- <entry>If the keyboard is actively grabbed by the client and is frozen
- as the result of an event having been sent to the client (either from the
- activation of an
- <function>XGrabKey</function>
- or from a previous
- <function>XAllowEvents</function>
- with mode
- <symbol>SyncKeyboard</symbol>
- but not from an
- <function>XGrabKeyboard</function>),
- the keyboard grab is released and that event is completely reprocessed.
- This time, however, the function ignores any passive grabs at or above
- (toward the root of)
- the grab_window of the grab just released.
- The request has no effect if the keyboard is not grabbed by the client
- or if the keyboard is not frozen as the result of an event.</entry>
- </row>
- <row>
- <entry><symbol>SyncBoth</symbol></entry>
- <entry>If both pointer and keyboard are frozen by the client,
- event processing for both devices continues as usual until the next
- <symbol>ButtonPress</symbol>,
- <symbol>ButtonRelease</symbol>,
- <symbol>KeyPress</symbol>,
- or
- <symbol>KeyRelease</symbol>
- event is reported to the client for a grabbed device
- (button event for the pointer, key event for the keyboard),
- at which time the devices again appear to freeze.
- However, if the reported event causes the grab to be released,
- then the devices do not freeze (but if the other device is still
- grabbed, then a subsequent event for it will still cause both devices
- to freeze).
- <symbol>SyncBoth</symbol>
- has no effect unless both pointer and keyboard
- are frozen by the client.
- If the pointer or keyboard is frozen twice
- by the client on behalf of two separate grabs,
- <symbol>SyncBoth</symbol>
- thaws for both (but a subsequent freeze for
- <symbol>SyncBoth</symbol>
- will only freeze each device once).</entry>
- </row>
- <row>
- <entry><symbol>AsyncBoth</symbol></entry>
- <entry>If the pointer and the keyboard are frozen by the
- client, event processing for both devices continues as usual.
- If a device is frozen twice by the client on behalf of two separate grabs,
- <symbol>AsyncBoth</symbol>
- thaws for both.
- <symbol>AsyncBoth</symbol>
- has no effect unless both
- pointer and keyboard are frozen by the client.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-<symbol>AsyncPointer</symbol>,
-<symbol>SyncPointer</symbol>,
-and
-<symbol>ReplayPointer</symbol>
-have no effect on the
-processing of keyboard events.
-<symbol>AsyncKeyboard</symbol>,
-<symbol>SyncKeyboard</symbol>,
-and
-<symbol>ReplayKeyboard</symbol>
-have no effect on the
-processing of pointer events.
-It is possible for both a pointer grab and a keyboard grab (by the same
-or different clients) to be active simultaneously.
-If a device is frozen on behalf of either grab,
-no event processing is performed for the device.
-It is possible for a single device to be frozen because of both grabs.
-In this case,
-the freeze must be released on behalf of both grabs before events can
-again be processed.
-If a device is frozen twice by a single client,
-then a single
-<function>XAllowEvents</function>
-releases both.
-</para>
-<para>
-<!-- .LP -->
-<function>XAllowEvents</function>
-can generate a
-<errorname>BadValue</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Moving_the_Pointer">
-<title>Moving the Pointer</title>
-<!-- .XS -->
-<!-- (SN Moving the Pointer -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Although movement of the pointer normally should be left to the
-control of the end user, sometimes it is necessary to move the
-pointer to a new position under program control.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To move the pointer to an arbitrary point in a window, use
-<function>XWarpPointer</function>.
-<indexterm significance="preferred"><primary>XWarpPointer</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XWarpPointer</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Windowsrc_w,<parameter> dest_w</parameter></paramdef>
- <paramdef>intsrc_x,<parameter> src_y</parameter></paramdef>
- <paramdef>unsignedintsrc_width,<parameter> src_height</parameter></paramdef>
- <paramdef>intdest_x,<parameter> dest_y</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src_w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the source window or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the destination window or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src_x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src_y</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src_width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src_height</emphasis>
- </term>
- <listitem>
- <para>
-Specify a rectangle in the source window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates within the destination window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If dest_w is
-<symbol>None</symbol>,
-<function>XWarpPointer</function>
-moves the pointer by the offsets (dest_x, dest_y) relative to the current
-position of the pointer.
-If dest_w is a window,
-<function>XWarpPointer</function>
-moves the pointer to the offsets (dest_x, dest_y) relative to the origin of
-dest_w.
-However, if src_w is a window,
-the move only takes place if the window src_w contains the pointer
-and if the specified rectangle of src_w contains the pointer.
-</para>
-<para>
-<!-- .LP -->
-The src_x and src_y coordinates are relative to the origin of src_w.
-If src_height is zero,
-it is replaced with the current height of src_w minus src_y.
-If src_width is zero,
-it is replaced with the current width of src_w minus src_x.
-</para>
-<para>
-<!-- .LP -->
-There is seldom any reason for calling this function.
-The pointer should normally be left to the user.
-If you do use this function, however, it generates events just as if the user
-had instantaneously moved the pointer from one position to another.
-Note that you cannot use
-<function>XWarpPointer</function>
-to move the pointer outside the confine_to window of an active pointer grab.
-An attempt to do so will only move the pointer as far as the closest edge of the
-confine_to window.
-</para>
-<para>
-<!-- .LP -->
-<function>XWarpPointer</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect1>
-<sect1 id="Controlling_Input_Focus">
-<title>Controlling Input Focus</title>
-<!-- .XS -->
-<!-- (SN Controlling Input Focus -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set and get the input focus.
-The input focus is a shared resource, and cooperation among clients is
-required for correct interaction. See the
-<emphasis remap='I'>Inter-Client Communication Conventions Manual</emphasis>
-for input focus policy.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the input focus, use
-<function>XSetInputFocus</function>.
-<indexterm significance="preferred"><primary>XSetInputFocus</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetInputFocus</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> focus</parameter></paramdef>
- <paramdef>int<parameter> revert_to</parameter></paramdef>
- <paramdef>Time<parameter> time</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>focus</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window,
-<symbol>PointerRoot</symbol>,
-or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>revert_to</emphasis>
- </term>
- <listitem>
- <para>
-Specifies where the input focus reverts to if the window becomes not
-viewable.
-You can pass
-<symbol>RevertToParent</symbol>,
-<symbol>RevertToPointerRoot</symbol>,
-or
-<symbol>RevertToNone</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>time</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the time.
-You can pass either a timestamp or
-<symbol>CurrentTime</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetInputFocus</function>
-function changes the input focus and the last-focus-change time.
-It has no effect if the specified time is earlier than the current
-last-focus-change time or is later than the current X server time.
-Otherwise, the last-focus-change time is set to the specified time
-(<symbol>CurrentTime</symbol>
-is replaced by the current X server time).
-<function>XSetInputFocus</function>
-causes the X server to generate
-<symbol>FocusIn</symbol>
-and
-<symbol>FocusOut</symbol>
-events.
-</para>
-<para>
-<!-- .LP -->
-Depending on the focus argument,
-the following occurs:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-If focus is
-<symbol>None</symbol>,
-all keyboard events are discarded until a new focus window is set,
-and the revert_to argument is ignored.
- </para>
- </listitem>
- <listitem>
- <para>
-If focus is a window,
-it becomes the keyboard's focus window.
-If a generated keyboard event would normally be reported to this window
-or one of its inferiors, the event is reported as usual.
-Otherwise, the event is reported relative to the focus window.
- </para>
- </listitem>
- <listitem>
- <para>
-If focus is
-<symbol>PointerRoot</symbol>,
-the focus window is dynamically taken to be the root window of whatever screen
-the pointer is on at each keyboard event.
-In this case, the revert_to argument is ignored.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The specified focus window must be viewable at the time
-<function>XSetInputFocus</function>
-is called,
-or a
-<errorname>BadMatch</errorname>
-error results.
-If the focus window later becomes not viewable,
-the X server
-evaluates the revert_to argument to determine the new focus window as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-If revert_to is
-<symbol>RevertToParent</symbol>,
-the focus reverts to the parent (or the closest viewable ancestor),
-and the new revert_to value is taken to be
-<symbol>RevertToNone</symbol>.
- </para>
- </listitem>
- <listitem>
- <para>
-If revert_to is
-<symbol>RevertToPointerRoot</symbol>
-or
-<symbol>RevertToNone</symbol>,
-the focus reverts to
-<symbol>PointerRoot</symbol>
-or
-<symbol>None</symbol>,
-respectively.
-When the focus reverts,
-the X server generates
-<symbol>FocusIn</symbol>
-and
-<symbol>FocusOut</symbol>
-events, but the last-focus-change time is not affected.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-<function>XSetInputFocus</function>
-can generate
-<errorname>BadMatch</errorname>,
-<errorname>BadValue</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the current input focus, use
-<function>XGetInputFocus</function>.
-<indexterm significance="preferred"><primary>XGetInputFocus</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XGetInputFocus</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> *focus_return</parameter></paramdef>
- <paramdef>int<parameter> *revert_to_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>focus_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the focus window,
-<symbol>PointerRoot</symbol>,
-or
-<symbol>None</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>revert_to_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the current focus state
-(<symbol>RevertToParent</symbol>,
-<symbol>RevertToPointerRoot</symbol>,
-or
-<symbol>RevertToNone</symbol>).
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetInputFocus</function>
-function returns the focus window and the current focus state.
-</para>
-</sect1>
-<sect1 id="Manipulating_the_Keyboard_and_Pointer_Settings">
-<title>Manipulating the Keyboard and Pointer Settings</title>
-<!-- .XS -->
-<!-- (SN Manipulating the Keyboard and Pointer Settings -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to
-change the keyboard control, obtain a list of the auto-repeat keys,
-turn keyboard auto-repeat on or off, ring the bell,
-set or obtain the pointer button or keyboard mapping,
-and obtain a bit vector for the keyboard.
-</para>
-<para>
-<!-- .LP -->
-<indexterm><primary>Keyboard</primary><secondary>bell volume</secondary></indexterm>
-<indexterm><primary>Keyboard</primary><secondary>keyclick volume</secondary></indexterm>
-<indexterm><primary>Keyboard</primary><secondary>bit vector</secondary></indexterm>
-<indexterm><primary>Mouse</primary><secondary>programming</secondary></indexterm>
-This section discusses
-the user-preference options of bell, key click,
-pointer behavior, and so on.
-The default values for many of these options are server dependent.
-Not all implementations will actually be able to control all of these
-parameters.
-</para>
-<para>
-<!-- .LP -->
-The
-<function>XChangeKeyboardControl</function>
-function changes control of a keyboard and operates on a
-<structname>XKeyboardControl</structname>
-structure:
-<!-- .sM -->
-</para>
-
-<literallayout class="monospaced">
-/* Mask bits for ChangeKeyboardControl */
-
-
-#define KBBellPercent (1L&lt;&lt;0)
-#define KBBellPitch (1L&lt;&lt;1)
-#define KBBellDuration (1L&lt;&lt;2)
-#define KBLed (1L&lt;&lt;3)
-#define KBLedMode (1L&lt;&lt;4)
-#define KBKey (1L&lt;&lt;5)
-#define KBAutoRepeatMode (1L&lt;&lt;6)
-
-
-/* Values */
-
-typedef struct {
-int key_click_percent;
-int bell_percent;
-int bell_pitch;
-int bell_duration;
-int led;
-int led_mode; /* LedModeOn, LedModeOff */
-int key;
-int auto_repeat_mode; /* AutoRepeatModeOff, AutoRepeatModeOn,
- AutoRepeatModeDefault */
-} XKeyboardControl;
-
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The key_click_percent member sets the volume for key clicks between 0 (off)
-and 100 (loud) inclusive, if possible.
-A setting of -1 restores the default.
-Other negative values generate a
-<errorname>BadValue</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-The bell_percent sets the base volume for the bell between 0 (off) and 100
-(loud) inclusive, if possible.
-A setting of -1 restores the default.
-Other negative values generate a
-<errorname>BadValue</errorname>
-error.
-The bell_pitch member sets the pitch (specified in Hz) of the bell, if possible.
-A setting of -1 restores the default.
-Other negative values generate a
-<errorname>BadValue</errorname>
-error.
-The bell_duration member sets the duration of the
-bell specified in milliseconds, if possible.
-A setting of -1 restores the default.
-Other negative values generate a
-<errorname>BadValue</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-If both the led_mode and led members are specified,
-the state of that <acronym>LED</acronym> is changed, if possible.
-The led_mode member can be set to
-<symbol>LedModeOn</symbol>
-or
-<symbol>LedModeOff</symbol>.
-If only led_mode is specified, the state of
-all LEDs are changed, if possible.
-At most 32 LEDs numbered from one are supported.
-No standard interpretation of LEDs is defined.
-If led is specified without led_mode, a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-If both the auto_repeat_mode and key members are specified,
-the auto_repeat_mode of that key is changed (according to
-<symbol>AutoRepeatModeOn</symbol>,
-<symbol>AutoRepeatModeOff</symbol>,
-or
-<symbol>AutoRepeatModeDefault</symbol>),
-if possible.
-If only auto_repeat_mode is
-specified, the global auto_repeat_mode for the entire keyboard is
-changed, if possible, and does not affect the per-key settings.
-If a key is specified without an auto_repeat_mode, a
-<errorname>BadMatch</errorname>
-error results.
-Each key has an individual mode of whether or not it should auto-repeat
-and a default setting for the mode.
-In addition,
-there is a global mode of whether auto-repeat should be enabled or not
-and a default setting for that mode.
-When global mode is
-<symbol>AutoRepeatModeOn</symbol>,
-keys should obey their individual auto-repeat modes.
-When global mode is
-<symbol>AutoRepeatModeOff</symbol>,
-no keys should auto-repeat.
-An auto-repeating key generates alternating
-<symbol>KeyPress</symbol>
-and
-<symbol>KeyRelease</symbol>
-events.
-When a key is used as a modifier,
-it is desirable for the key not to auto-repeat,
-regardless of its auto-repeat setting.
-</para>
-<para>
-<!-- .LP -->
-A bell generator connected with the console but not directly on a
-keyboard is treated as if it were part of the keyboard.
-The order in which controls are verified and altered is server-dependent.
-If an error is generated, a subset of the controls may have been altered.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-<indexterm significance="preferred"><primary>XChangeKeyboardControl</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XChangeKeyboardControl</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>unsignedlong<parameter> value_mask</parameter></paramdef>
- <paramdef>XKeyboardControl<parameter> *values</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which controls to change.
-This mask is the bitwise inclusive OR of the valid control mask bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>values</emphasis>
- </term>
- <listitem>
- <para>
-Specifies one value for each bit set to 1 in the mask.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XChangeKeyboardControl</function>
-function controls the keyboard characteristics defined by the
-<structname>XKeyboardControl</structname>
-structure.
-The value_mask argument specifies which values are to be changed.
-</para>
-<para>
-<!-- .LP -->
-<function>XChangeKeyboardControl</function>
-can generate
-<errorname>BadMatch</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the current control values for the keyboard, use
-<function>XGetKeyboardControl</function>.
-<indexterm significance="preferred"><primary>XGetKeyboardControl</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XGetKeyboardControl</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XKeyboardState<parameter> *values_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>values_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the current keyboard controls in the specified
-<structname>XKeyboardState</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetKeyboardControl</function>
-function returns the current control values for the keyboard to the
-<structname>XKeyboardState</structname>
-structure.
-</para>
-<para>
-<!-- .LP -->
-<indexterm><primary>XGetKeyboardControl</primary></indexterm>
-<indexterm significance="preferred"><primary>XKeyboardState</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i -->
-<!-- .ta .5i -->
-typedef struct {
- int key_click_percent;
- int bell_percent;
- unsigned int bell_pitch, bell_duration;
- unsigned long led_mask;
- int global_auto_repeat;
- char auto_repeats[32];
-} XKeyboardState;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-For the LEDs,
-the least significant bit of led_mask corresponds to <acronym>LED</acronym> one,
-and each bit set to 1 in led_mask indicates an <acronym>LED</acronym> that is lit.
-The global_auto_repeat member can be set to
-<symbol>AutoRepeatModeOn</symbol>
-or
-<symbol>AutoRepeatModeOff</symbol>.
-The auto_repeats member is a bit vector.
-Each bit set to 1 indicates that auto-repeat is enabled
-for the corresponding key.
-The vector is represented as 32 bytes.
-Byte N (from 0) contains the bits for keys 8N to 8N + 7
-with the least significant bit in the byte representing key 8N.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To turn on keyboard auto-repeat, use
-<function>XAutoRepeatOn</function>.
-<indexterm significance="preferred"><primary>XAutoRepeatOn</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XAutoRepeatOn</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAutoRepeatOn</function>
-function turns on auto-repeat for the keyboard on the specified display.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To turn off keyboard auto-repeat, use
-<function>XAutoRepeatOff</function>.
-<indexterm significance="preferred"><primary>XAutoRepeatOff</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XAutoRepeatOff</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAutoRepeatOff</function>
-function turns off auto-repeat for the keyboard on the specified display.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To ring the bell, use
-<function>XBell</function>.
-<indexterm significance="preferred"><primary>XBell</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XBell</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> percent</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>percent</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the volume for the bell,
-which can range from -100 to 100 inclusive.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XBell</function>
-function rings the bell on the keyboard on the specified display, if possible.
-The specified volume is relative to the base volume for the keyboard.
-If the value for the percent argument is not in the range -100 to 100
-inclusive, a
-<errorname>BadValue</errorname>
-error results.
-The volume at which the bell rings
-when the percent argument is nonnegative is:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-base - [(base * percent) / 100] + percent
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The volume at which the bell rings
-when the percent argument is negative is:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-base + [(base * percent) / 100]
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-To change the base volume of the bell, use
-<function>XChangeKeyboardControl</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XBell</function>
-can generate a
-<errorname>BadValue</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain a bit vector that describes the state of the keyboard, use
-<function>XQueryKeymap</function>.
-<indexterm significance="preferred"><primary>XQueryKeymap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XQueryKeymap</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> keys_return[32]</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keys_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns an array of bytes that identifies which keys are pressed down.
-Each bit represents one key of the keyboard.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XQueryKeymap</function>
-function returns a bit vector for the logical state of the keyboard,
-where each bit set to 1 indicates that the corresponding key is currently
-pressed down.
-The vector is represented as 32 bytes.
-Byte N (from 0) contains the bits for keys 8N to 8N + 7
-with the least significant bit in the byte representing key 8N.
-</para>
-<para>
-<!-- .LP -->
-Note that the logical state of a device (as seen by client applications)
-may lag the physical state if device event processing is frozen.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the mapping of the pointer buttons, use
-<function>XSetPointerMapping</function>.
-<indexterm significance="preferred"><primary>XSetPointerMapping</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XSetPointerMapping</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>unsignedchar<parameter> map[]</parameter></paramdef>
- <paramdef>int<parameter> nmap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>map</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the mapping list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nmap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of items in the mapping list.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetPointerMapping</function>
-function sets the mapping of the pointer.
-If it succeeds, the X server generates a
-<symbol>MappingNotify</symbol>
-event, and
-<function>XSetPointerMapping</function>
-returns
-<symbol>MappingSuccess</symbol>.
-Element map[i] defines the logical button number for the physical button
-i+1.
-The length of the list must be the same as
-<function>XGetPointerMapping</function>
-would return,
-or a
-<errorname>BadValue</errorname>
-error results.
-A zero element disables a button, and elements are not restricted in
-value by the number of physical buttons.
-However, no two elements can have the same nonzero value,
-or a
-<errorname>BadValue</errorname>
-error results.
-If any of the buttons to be altered are logically in the down state,
-<function>XSetPointerMapping</function>
-returns
-<symbol>MappingBusy</symbol>,
-and the mapping is not changed.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetPointerMapping</function>
-can generate a
-<errorname>BadValue</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To get the pointer mapping, use
-<function>XGetPointerMapping</function>.
-<indexterm significance="preferred"><primary>XGetPointerMapping</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XGetPointerMapping</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>unsignedchar<parameter> map_return[]</parameter></paramdef>
- <paramdef>int<parameter> nmap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>map_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the mapping list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nmap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of items in the mapping list.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetPointerMapping</function>
-function returns the current mapping of the pointer.
-Pointer buttons are numbered starting from one.
-<function>XGetPointerMapping</function>
-returns the number of physical buttons actually on the pointer.
-The nominal mapping for a pointer is map[i]=i+1.
-The nmap argument specifies the length of the array where the pointer
-mapping is returned, and only the first nmap elements are returned
-in map_return.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To control the pointer's interactive feel, use
-<function>XChangePointerControl</function>.
-<indexterm significance="preferred"><primary>XChangePointerControl</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XChangePointerControl</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Booldo_accel,<parameter> do_threshold</parameter></paramdef>
- <paramdef>intaccel_numerator,<parameter> accel_denominator</parameter></paramdef>
- <paramdef>int<parameter> threshold</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>do_accel</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value that controls whether the values for
-the accel_numerator or accel_denominator are used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>do_threshold</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a Boolean value that controls whether the value for the
-threshold is used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>accel_numerator</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the numerator for the acceleration multiplier.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>accel_denominator</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the denominator for the acceleration multiplier.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>threshold</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the acceleration threshold.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XChangePointerControl</function>
-function defines how the pointing device moves.
-The acceleration, expressed as a fraction, is a
-multiplier for movement.
-For example,
-specifying 3/1 means the pointer moves three times as fast as normal.
-The fraction may be rounded arbitrarily by the X server.
-Acceleration
-only takes effect if the pointer moves more than threshold pixels at
-once and only applies to the amount beyond the value in the threshold argument.
-Setting a value to -1 restores the default.
-The values of the do_accel and do_threshold arguments must be
-<symbol>True</symbol>
-for the pointer values to be set,
-or the parameters are unchanged.
-Negative values (other than -1) generate a
-<errorname>BadValue</errorname>
-error, as does a zero value
-for the accel_denominator argument.
-</para>
-<para>
-<!-- .LP -->
-<function>XChangePointerControl</function>
-can generate a
-<errorname>BadValue</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To get the current pointer parameters, use
-<function>XGetPointerControl</function>.
-<indexterm significance="preferred"><primary>XGetPointerControl</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XGetPointerControl</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int*accel_numerator_return,<parameter> *accel_denominator_return</parameter></paramdef>
- <paramdef>int<parameter> *threshold_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>accel_numerator_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the numerator for the acceleration multiplier.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>accel_denominator_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the denominator for the acceleration multiplier.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>threshold_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the acceleration threshold.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetPointerControl</function>
-function returns the pointer's current acceleration multiplier
-and acceleration threshold.
-</para>
-</sect1>
-<sect1 id="Manipulating_the_Keyboard_Encoding">
-<title>Manipulating the Keyboard Encoding</title>
-<!-- .XS -->
-<!-- (SN Manipulating the Keyboard Encoding -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-A KeyCode represents a physical (or logical) key.
-KeyCodes lie in the inclusive range [8,255].
-A KeyCode value carries no intrinsic information,
-although server implementors may attempt to encode geometry
-(for example, matrix) information in some fashion so that it can
-be interpreted in a server-dependent fashion.
-The mapping between keys and KeyCodes cannot be changed.
-</para>
-<para>
-<!-- .LP -->
-A KeySym is an encoding of a symbol on the cap of a key.
-The set of defined KeySyms includes the ISO Latin character sets (1-4),
-Katakana, Arabic, Cyrillic, Greek, Technical,
-Special, Publishing, APL, Hebrew, Thai, Korean
-and a miscellany of keys found
-on keyboards (Return, Help, Tab, and so on).
-To the extent possible, these sets are derived from international
-standards.
-In areas where no standards exist,
-some of these sets are derived from Digital Equipment Corporation standards.
-The list of defined symbols can be found in
-<filename class="headerfile">&lt;X11/keysymdef.h&gt;</filename>.
-<indexterm type="file"><primary><filename class="headerfile">X11/keysymdef.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/keysymdef.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/keysymdef.h&gt;</filename></secondary></indexterm>
-Unfortunately, some C preprocessors have
-limits on the number of defined symbols.
-If you must use KeySyms not
-in the Latin 1-4, Greek, and miscellaneous classes,
-you may have to define a symbol for those sets.
-Most applications usually only include
-<filename class="headerfile">&lt;X11/keysym.h&gt;</filename>,
-<indexterm type="file"><primary><filename class="headerfile">X11/keysym.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/keysym.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/keysym.h&gt;</filename></secondary></indexterm>
-which defines symbols for ISO Latin 1-4, Greek, and miscellaneous.
-</para>
-<para>
-<!-- .LP -->
-A list of KeySyms is associated with each KeyCode.
-The list is intended to convey the set of symbols on the corresponding key.
-If the list (ignoring trailing
-<symbol>NoSymbol</symbol>
-entries) is
-a single KeySym ``<emphasis remap='I'>K</emphasis>'',
-then the list is treated as if it were the list
-``<emphasis remap='I'>K</emphasis> NoSymbol <emphasis remap='I'>K</emphasis> NoSymbol''.
-If the list (ignoring trailing
-<symbol>NoSymbol</symbol>
-entries) is a pair of KeySyms ``<emphasis remap='I'>K1 K2</emphasis>'',
-then the list is treated as if it were the list ``<emphasis remap='I'>K1 K2 K1 K2</emphasis>''.
-If the list (ignoring trailing
-<symbol>NoSymbol</symbol>
-entries) is a triple of KeySyms ``<emphasis remap='I'>K1 K2 K3</emphasis>'',
-then the list is treated as if it were the list ``<emphasis remap='I'>K1 K2 K3</emphasis> NoSymbol''.
-When an explicit ``void'' element is desired in the list,
-the value
-<symbol>VoidSymbol</symbol>
-can be used.
-</para>
-<para>
-<!-- .LP -->
-The first four elements of the list are split into two groups of KeySyms.
-Group 1 contains the first and second KeySyms;
-Group 2 contains the third and fourth KeySyms.
-Within each group,
-if the second element of the group is
-<symbol>NoSymbol</symbol>,
-then the group should be treated as if the second element were
-the same as the first element,
-except when the first element is an alphabetic KeySym ``<emphasis remap='I'>K</emphasis>''
-for which both lowercase and uppercase forms are defined.
-In that case,
-the group should be treated as if the first element were
-the lowercase form of ``<emphasis remap='I'>K</emphasis>'' and the second element were
-the uppercase form of ``<emphasis remap='I'>K</emphasis>''.
-</para>
-<para>
-<!-- .LP -->
-The standard rules for obtaining a KeySym from a
-<symbol>KeyPress</symbol>
-event make use of only the Group 1 and Group 2 KeySyms;
-no interpretation of other KeySyms in the list is given.
-Which group to use is determined by the modifier state.
-Switching between groups is controlled by the KeySym named MODE SWITCH,
-by attaching that KeySym to some KeyCode and attaching
-that KeyCode to any one of the modifiers
-<symbol>Mod1</symbol>
-through
-<symbol>Mod5</symbol>.
-This modifier is called the <emphasis remap='I'>group modifier</emphasis>.
-For any KeyCode,
-Group 1 is used when the group modifier is off,
-and Group 2 is used when the group modifier is on.
-</para>
-<para>
-<!-- .LP -->
-The
-<symbol>Lock</symbol>
-modifier is interpreted as CapsLock when the KeySym named XK_Caps_Lock
-is attached to some KeyCode and that KeyCode is attached to the
-<symbol>Lock</symbol>
-modifier. The
-<symbol>Lock</symbol>
-modifier is interpreted as ShiftLock when the KeySym named XK_Shift_Lock
-is attached to some KeyCode and that KeyCode is attached to the
-<symbol>Lock</symbol>
-modifier. If the
-<symbol>Lock</symbol>
-modifier could be interpreted as both
-CapsLock and ShiftLock, the CapsLock interpretation is used.
-</para>
-<para>
-<!-- .LP -->
-The operation of keypad keys is controlled by the KeySym named XK_Num_Lock,
-by attaching that KeySym to some KeyCode and attaching that KeyCode to any
-one of the modifiers
-<symbol>Mod1</symbol>
-through
-<symbol>Mod5</symbol>.
-This modifier is called the
-<emphasis remap='I'>numlock modifier</emphasis>. The standard KeySyms with the prefix ``XK_KP_''
-in their
-name are called keypad KeySyms; these are KeySyms with numeric value in
-the hexadecimal range 0xFF80 to 0xFFBD inclusive. In addition,
-vendor-specific KeySyms in the hexadecimal range 0x11000000 to 0x1100FFFF
-are also keypad KeySyms.
-</para>
-<para>
-<!-- .LP -->
-Within a group, the choice of KeySym is determined by applying the first
-rule that is satisfied from the following list:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The numlock modifier is on and the second KeySym is a keypad KeySym. In
-this case, if the
-<symbol>Shift</symbol>
-modifier is on, or if the
-<symbol>Lock</symbol>
-modifier is on and
-is interpreted as ShiftLock, then the first KeySym is used, otherwise the
-second KeySym is used.
- </para>
- </listitem>
- <listitem>
- <para>
-The
-<symbol>Shift</symbol>
-and
-<symbol>Lock</symbol>
-modifiers are both off. In this case, the first
-KeySym is used.
- </para>
- </listitem>
- <listitem>
- <para>
-The
-<symbol>Shift</symbol>
-modifier is off, and the
-<symbol>Lock</symbol>
-modifier is on and is
-interpreted as CapsLock. In this case, the first KeySym is used, but if
-that KeySym is lowercase alphabetic, then the corresponding uppercase
-KeySym is used instead.
- </para>
- </listitem>
- <listitem>
- <para>
-The
-<symbol>Shift</symbol>
-modifier is on, and the
-<symbol>Lock</symbol>
-modifier is on and is interpreted
-as CapsLock. In this case, the second KeySym is used, but if that KeySym
-is lowercase alphabetic, then the corresponding uppercase KeySym is used
-instead.
- </para>
- </listitem>
- <listitem>
- <para>
-The
-<symbol>Shift</symbol>
-modifier is on, or the
-<symbol>Lock</symbol>
-modifier is on and is interpreted
-as ShiftLock, or both. In this case, the second KeySym is used.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-No spatial geometry of the symbols on the key is defined by
-their order in the KeySym list,
-although a geometry might be defined on a
-server-specific basis.
-The X server does not use the mapping between KeyCodes and KeySyms.
-Rather, it merely stores it for reading and writing by clients.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the legal KeyCodes for a display, use
-<function>XDisplayKeycodes</function>.
-<indexterm significance="preferred"><primary>XDisplayKeycodes</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDisplayKeycodes</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int*min_keycodes_return,<parameter> *max_keycodes_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>min_keycodes_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the minimum number of KeyCodes.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>max_keycodes_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the maximum number of KeyCodes.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDisplayKeycodes</function>
-function returns the min-keycodes and max-keycodes supported by the
-specified display.
-The minimum number of KeyCodes returned is never less than 8,
-and the maximum number of KeyCodes returned is never greater than 255.
-Not all KeyCodes in this range are required to have corresponding keys.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the symbols for the specified KeyCodes, use
-<function>XGetKeyboardMapping</function>.
-<indexterm significance="preferred"><primary>XGetKeyboardMapping</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>KeySym *<function>XGetKeyboardMapping</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>KeyCode<parameter> first_keycode</parameter></paramdef>
- <paramdef>int<parameter> keycode_count</parameter></paramdef>
- <paramdef>int<parameter> *keysyms_per_keycode_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Kc returned -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>first_keycode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the first KeyCode that is to be (Kc.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keycode_count</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of KeyCodes that are to be returned.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysyms_per_keycode_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of KeySyms per KeyCode.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetKeyboardMapping</function>
-function returns the symbols for the specified number of KeyCodes
-starting with first_keycode.
-The value specified in first_keycode must be greater than
-or equal to min_keycode as returned by
-<function>XDisplayKeycodes</function>,
-or a
-<errorname>BadValue</errorname>
-error results.
-In addition, the following expression must be less than or equal
-to max_keycode as returned by
-<function>XDisplayKeycodes</function>:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-first_keycode + keycode_count - 1
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-If this is not the case, a
-<errorname>BadValue</errorname>
-error results.
-The number of elements in the KeySyms list is:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-keycode_count * keysyms_per_keycode_return
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-KeySym number N, counting from zero, for KeyCode K has the following index
-in the list, counting from zero:
-<literallayout class="monospaced">
-(K - first_code) * keysyms_per_code_return + N
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The X server arbitrarily chooses the keysyms_per_keycode_return value
-to be large enough to report all requested symbols.
-A special KeySym value of
-<symbol>NoSymbol</symbol>
-is used to fill in unused elements for
-individual KeyCodes.
-To free the storage returned by
-<function>XGetKeyboardMapping</function>,
-use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetKeyboardMapping</function>
-can generate a
-<errorname>BadValue</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To change the keyboard mapping, use
-<function>XChangeKeyboardMapping</function>.
-<indexterm significance="preferred"><primary>XChangeKeyboardMapping</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XChangeKeyboardMapping</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> first_keycode</parameter></paramdef>
- <paramdef>int<parameter> keysyms_per_keycode</parameter></paramdef>
- <paramdef>KeySym<parameter> *keysyms</parameter></paramdef>
- <paramdef>int<parameter> num_codes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Kc changed -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>first_keycode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the first KeyCode that is to be (Kc.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysyms_per_keycode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of KeySyms per KeyCode.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysyms</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of KeySyms.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_codes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of KeyCodes that are to be changed.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XChangeKeyboardMapping</function>
-function defines the symbols for the specified number of KeyCodes
-starting with first_keycode.
-The symbols for KeyCodes outside this range remain unchanged.
-The number of elements in keysyms must be:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-num_codes * keysyms_per_keycode
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The specified first_keycode must be greater than or equal to min_keycode
-returned by
-<function>XDisplayKeycodes</function>,
-or a
-<errorname>BadValue</errorname>
-error results.
-In addition, the following expression must be less than or equal to
-max_keycode as returned by
-<function>XDisplayKeycodes</function>,
-or a
-<errorname>BadValue</errorname>
-error results:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-first_keycode + num_codes - 1
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-KeySym number N, counting from zero, for KeyCode K has the following index
-in keysyms, counting from zero:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-(K - first_keycode) * keysyms_per_keycode + N
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The specified keysyms_per_keycode can be chosen arbitrarily by the client
-to be large enough to hold all desired symbols.
-A special KeySym value of
-<symbol>NoSymbol</symbol>
-should be used to fill in unused elements
-for individual KeyCodes.
-It is legal for
-<symbol>NoSymbol</symbol>
-to appear in nontrailing positions
-of the effective list for a KeyCode.
-<function>XChangeKeyboardMapping</function>
-generates a
-<symbol>MappingNotify</symbol>
-event.
-</para>
-<para>
-<!-- .LP -->
-There is no requirement that the X server interpret this mapping.
-It is merely stored for reading and writing by clients.
-</para>
-<para>
-<!-- .LP -->
-<function>XChangeKeyboardMapping</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-The next six functions make use of the
-<structname>XModifierKeymap</structname>
-data structure, which contains:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XModifierKeymap</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- int max_keypermod; /* This server's max number of keys per modifier */
- KeyCode *modifiermap; /* An 8 by max_keypermod array of the modifiers */
-} XModifierKeymap;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-To create an
-<structname>XModifierKeymap</structname>
-structure, use
-<function>XNewModifiermap</function>.
-<indexterm significance="preferred"><primary>XNewModifiermap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XModifierKeymap *<function>XNewModifiermap</function></funcdef>
- <paramdef>int<parameter> max_keys_per_mod</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>max_keys_per_mod</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of KeyCode entries preallocated to the modifiers
-in the map.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XNewModifiermap</function>
-function returns a pointer to
-<structname>XModifierKeymap</structname>
-structure for later use.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To add a new entry to an
-<structname>XModifierKeymap</structname>
-structure, use
-<function>XInsertModifiermapEntry</function>.
-<indexterm significance="preferred"><primary>XInsertModifiermapEntry</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XModifierKeymap *<function>XInsertModifiermapEntry</function></funcdef>
- <paramdef>XModifierKeymap<parameter> *modmap</parameter></paramdef>
- <paramdef>KeyCode<parameter> keycode_entry</parameter></paramdef>
- <paramdef>int<parameter> modifier</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>modmap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XModifierKeymap</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keycode_entry</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeyCode.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>modifier</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the modifier.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XInsertModifiermapEntry</function>
-function adds the specified KeyCode to the set that controls the specified
-modifier and returns the resulting
-<structname>XModifierKeymap</structname>
-structure (expanded as needed).
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To delete an entry from an
-<structname>XModifierKeymap</structname>
-structure, use
-<function>XDeleteModifiermapEntry</function>.
-<indexterm significance="preferred"><primary>XDeleteModifiermapEntry</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XModifierKeymap *<function>XDeleteModifiermapEntry</function></funcdef>
- <paramdef>XModifierKeymap<parameter> *modmap</parameter></paramdef>
- <paramdef>KeyCode<parameter> keycode_entry</parameter></paramdef>
- <paramdef>int<parameter> modifier</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>modmap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XModifierKeymap</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keycode_entry</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeyCode.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>modifier</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the modifier.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDeleteModifiermapEntry</function>
-function deletes the specified KeyCode from the set that controls the
-specified modifier and returns a pointer to the resulting
-<structname>XModifierKeymap</structname>
-structure.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To destroy an
-<structname>XModifierKeymap</structname>
-structure, use
-<function>XFreeModifiermap</function>.
-<indexterm significance="preferred"><primary>XFreeModifiermap</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XFreeModifiermap</function></funcdef>
- <paramdef>XModifierKeymap<parameter> *modmap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>modmap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XModifierKeymap</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreeModifiermap</function>
-function frees the specified
-<structname>XModifierKeymap</structname>
-structure.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the KeyCodes to be used as modifiers, use
-<function>XSetModifierMapping</function>.
-<indexterm significance="preferred"><primary>XSetModifierMapping</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XSetModifierMapping</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XModifierKeymap<parameter> *modmap</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>modmap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XModifierKeymap</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetModifierMapping</function>
-function specifies the KeyCodes of the keys (if any) that are to be used
-as modifiers.
-If it succeeds,
-the X server generates a
-<symbol>MappingNotify</symbol>
-event, and
-<function>XSetModifierMapping</function>
-returns
-<symbol>MappingSuccess</symbol>.
-X permits at most 8 modifier keys.
-If more than 8 are specified in the
-<structname>XModifierKeymap</structname>
-structure, a
-<errorname>BadLength</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-The modifiermap member of the
-<structname>XModifierKeymap</structname>
-structure contains 8 sets of max_keypermod KeyCodes,
-one for each modifier in the order
-<symbol>Shift</symbol>,
-<symbol>Lock</symbol>,
-<symbol>Control</symbol>,
-<symbol>Mod1</symbol>,
-<symbol>Mod2</symbol>,
-<symbol>Mod3</symbol>,
-<symbol>Mod4</symbol>,
-and
-<symbol>Mod5</symbol>.
-Only nonzero KeyCodes have meaning in each set,
-and zero KeyCodes are ignored.
-In addition, all of the nonzero KeyCodes must be in the range specified by
-min_keycode and max_keycode in the
-<type>Display</type>
-structure,
-or a
-<errorname>BadValue</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-An X server can impose restrictions on how modifiers can be changed,
-for example,
-if certain keys do not generate up transitions in hardware,
-if auto-repeat cannot be disabled on certain keys,
-or if multiple modifier keys are not supported.
-If some such restriction is violated,
-the status reply is
-<symbol>MappingFailed</symbol>,
-and none of the modifiers are changed.
-If the new KeyCodes specified for a modifier differ from those
-currently defined and any (current or new) keys for that modifier are
-in the logically down state,
-<function>XSetModifierMapping</function>
-returns
-<symbol>MappingBusy</symbol>,
-and none of the modifiers is changed.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetModifierMapping</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the KeyCodes used as modifiers, use
-<function>XGetModifierMapping</function>.
-<indexterm significance="preferred"><primary>XGetModifierMapping</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XModifierKeymap *<function>XGetModifierMapping</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetModifierMapping</function>
-function returns a pointer to a newly created
-<structname>XModifierKeymap</structname>
-structure that contains the keys being used as modifiers.
-The structure should be freed after use by calling
-<function>XFreeModifiermap</function>.
-If only zero values appear in the set for any modifier,
-that modifier is disabled.
-<!-- .bp -->
-
-
-</para>
-</sect1>
-</chapter>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<chapter id="input_device_functions">
+<title>Input Device Functions</title>
+
+<para>
+You can use the Xlib input device functions to:
+</para>
+
+<itemizedlist>
+ <listitem><para>Grab the pointer and individual buttons on the pointer</para></listitem>
+ <listitem><para>Grab the keyboard and individual keys on the keyboard</para></listitem>
+ <listitem><para>Resume event processing</para></listitem>
+ <listitem><para>Move the pointer</para></listitem>
+ <listitem><para>Set the input focus</para></listitem>
+ <listitem><para>Manipulate the keyboard and pointer settings</para></listitem>
+ <listitem><para>Manipulate the keyboard encoding</para></listitem>
+</itemizedlist>
+
+<sect1 id="Pointer_Grabbing_">
+<title>Pointer Grabbing </title>
+<!-- .XS -->
+<!-- (SN Pointer Grabbing -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to control input from the pointer,
+which usually is a mouse.
+Usually, as soon as keyboard and mouse events occur,
+the X server delivers them to the appropriate client,
+which is determined by the window and input focus.
+The X server provides sufficient control over event delivery to
+allow window managers to support mouse ahead and various other
+styles of user interface.
+Many of these user interfaces depend on synchronous delivery of events.
+The delivery of pointer and keyboard events can be controlled
+independently.
+</para>
+<para>
+<!-- .LP -->
+When mouse buttons or keyboard keys are grabbed, events
+will be sent to the grabbing client rather than the normal
+client who would have received the event.
+If the keyboard or pointer is in asynchronous mode,
+further mouse and keyboard events will continue to be processed.
+If the keyboard or pointer is in synchronous mode, no
+further events are processed until the grabbing client
+allows them (see
+<function>XAllowEvents</function>).
+The keyboard or pointer is considered frozen during this
+interval.
+The event that triggered the grab can also be replayed.
+</para>
+<para>
+<!-- .LP -->
+Note that the logical state of a device (as seen by client applications)
+may lag the physical state if device event processing is frozen.
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>Active grab</primary></indexterm>
+There are two kinds of grabs:
+active and passive.
+An active grab occurs when a single client grabs the keyboard and/or pointer
+explicitly (see
+<function>XGrabPointer</function>
+and
+<function>XGrabKeyboard</function>).
+<indexterm><primary>Passive grab</primary></indexterm>
+A passive grab occurs when clients grab a particular keyboard key
+or pointer button in a window,
+and the grab will activate when the key or button is actually pressed.
+Passive grabs are convenient for implementing reliable pop-up menus.
+For example, you can guarantee that the pop-up is mapped
+before the up pointer button event occurs by
+grabbing a button requesting synchronous behavior.
+The down event will trigger the grab and freeze further
+processing of pointer events until you have the chance to
+map the pop-up window.
+You can then allow further event processing.
+The up event will then be correctly processed relative to the
+pop-up window.
+</para>
+<para>
+<!-- .LP -->
+For many operations,
+there are functions that take a time argument.
+The X server includes a timestamp in various events.
+One special time, called
+<indexterm significance="preferred"><primary>CurrentTime</primary></indexterm>
+<indexterm significance="preferred"><primary>Time</primary></indexterm>
+<symbol>CurrentTime</symbol>,
+represents the current server time.
+The X server maintains the time when the input focus was last changed,
+when the keyboard was last grabbed,
+when the pointer was last grabbed,
+or when a selection was last changed.
+Your
+application may be slow reacting to an event.
+You often need some way to specify that your
+request should not occur if another application has in the meanwhile
+taken control of the keyboard, pointer, or selection.
+By providing the timestamp from the event in the request,
+you can arrange that the operation not take effect
+if someone else has performed an operation in the meanwhile.
+</para>
+<para>
+<!-- .LP -->
+A timestamp is a time value, expressed in milliseconds.
+It typically is the time since the last server reset.
+Timestamp values wrap around (after about 49.7 days).
+The server, given its current time is represented by timestamp T,
+always interprets timestamps from clients by treating half of the timestamp
+space as being later in time than T.
+One timestamp value, named
+<symbol>CurrentTime</symbol>,
+is never generated by the server.
+This value is reserved for use in requests to represent the current server time.
+</para>
+<para>
+<!-- .LP -->
+For many functions in this section,
+you pass pointer event mask bits.
+The valid pointer event mask bits are:
+<symbol>ButtonPressMask</symbol>,
+<symbol>ButtonReleaseMask</symbol>,
+<symbol>EnterWindowMask</symbol>,
+<symbol>LeaveWindowMask</symbol>,
+<symbol>PointerMotionMask</symbol>,
+<symbol>PointerMotionHintMask</symbol>,
+<symbol>Button1MotionMask</symbol>,
+<symbol>Button2MotionMask</symbol>,
+<symbol>Button3MotionMask</symbol>,
+<symbol>Button4MotionMask</symbol>,
+<symbol>Button5MotionMask</symbol>,
+<symbol>ButtonMotionMask</symbol>,
+and
+<symbol>KeymapStateMask</symbol>.
+For other functions in this section,
+you pass keymask bits.
+The valid keymask bits are:
+<symbol>ShiftMask</symbol>,
+<symbol>LockMask</symbol>,
+<symbol>ControlMask</symbol>,
+<symbol>Mod1Mask</symbol>,
+<symbol>Mod2Mask</symbol>,
+<symbol>Mod3Mask</symbol>,
+<symbol>Mod4Mask</symbol>,
+and
+<symbol>Mod5Mask</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To grab the pointer, use
+<function>XGrabPointer</function>.
+<indexterm><primary>Grabbing</primary><secondary>pointer</secondary></indexterm>
+<indexterm><primary>Pointer</primary><secondary>grabbing</secondary></indexterm>
+<indexterm significance="preferred"><primary>XGrabPointer</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgrabpointer'>
+<funcprototype>
+ <funcdef>int <function>XGrabPointer</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> grab_window</parameter></paramdef>
+ <paramdef>Bool<parameter> owner_events</parameter></paramdef>
+ <paramdef>unsignedint<parameter> event_mask</parameter></paramdef>
+ <paramdef>intpointer_mode,<parameter> keyboard_mode</parameter></paramdef>
+ <paramdef>Window<parameter> confine_to</parameter></paramdef>
+ <paramdef>Cursor<parameter> cursor</parameter></paramdef>
+ <paramdef>Time<parameter> time</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>grab_window</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the grab window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>owner_events</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value that indicates whether the pointer
+events are to be reported as usual or reported with respect to the grab window
+if selected by the event mask.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which pointer events are reported to the client.
+The mask is the bitwise inclusive OR of the valid pointer event mask bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pointer_mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies further processing of pointer events.
+You can pass
+<symbol>GrabModeSync</symbol>
+or
+<symbol>GrabModeAsync</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keyboard_mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies further processing of keyboard events.
+You can pass
+<symbol>GrabModeSync</symbol>
+or
+<symbol>GrabModeAsync</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>confine_to</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window to confine the pointer in or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>cursor</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the cursor that is to be displayed during the grab or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>time</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the time.
+You can pass either a timestamp or
+<symbol>CurrentTime</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGrabPointer</function>
+function actively grabs control of the pointer and returns
+<symbol>GrabSuccess</symbol>
+if the grab was successful.
+Further pointer events are reported only to the grabbing client.
+<function>XGrabPointer</function>
+overrides any active pointer grab by this client.
+If owner_events is
+<symbol>False</symbol>,
+all generated pointer events
+are reported with respect to grab_window and are reported only if
+selected by event_mask.
+If owner_events is
+<symbol>True</symbol>
+and if a generated
+pointer event would normally be reported to this client,
+it is reported as usual.
+Otherwise, the event is reported with respect to the
+grab_window and is reported only if selected by event_mask.
+For either value of owner_events, unreported events are discarded.
+</para>
+<para>
+<!-- .LP -->
+If the pointer_mode is
+<symbol>GrabModeAsync</symbol>,
+pointer event processing continues as usual.
+If the pointer is currently frozen by this client,
+the processing of events for the pointer is resumed.
+If the pointer_mode is
+<symbol>GrabModeSync</symbol>,
+the state of the pointer, as seen by
+client applications,
+appears to freeze, and the X server generates no further pointer events
+until the grabbing client calls
+<function>XAllowEvents</function>
+or until the pointer grab is released.
+Actual pointer changes are not lost while the pointer is frozen;
+they are simply queued in the server for later processing.
+</para>
+<para>
+<!-- .LP -->
+If the keyboard_mode is
+<symbol>GrabModeAsync</symbol>,
+keyboard event processing is unaffected by activation of the grab.
+If the keyboard_mode is
+<symbol>GrabModeSync</symbol>,
+the state of the keyboard, as seen by
+client applications,
+appears to freeze, and the X server generates no further keyboard events
+until the grabbing client calls
+<function>XAllowEvents</function>
+or until the pointer grab is released.
+Actual keyboard changes are not lost while the pointer is frozen;
+they are simply queued in the server for later processing.
+</para>
+<para>
+<!-- .LP -->
+If a cursor is specified, it is displayed regardless of what
+window the pointer is in.
+If
+<symbol>None</symbol>
+is specified,
+the normal cursor for that window is displayed
+when the pointer is in grab_window or one of its subwindows;
+otherwise, the cursor for grab_window is displayed.
+</para>
+<para>
+<!-- .LP -->
+If a confine_to window is specified,
+the pointer is restricted to stay contained in that window.
+The confine_to window need have no relationship to the grab_window.
+If the pointer is not initially in the confine_to window,
+it is warped automatically to the closest edge
+just before the grab activates and enter/leave events are generated as usual.
+If the confine_to window is subsequently reconfigured,
+the pointer is warped automatically, as necessary,
+to keep it contained in the window.
+</para>
+<para>
+<!-- .LP -->
+The time argument allows you to avoid certain circumstances that come up
+if applications take a long time to respond or if there are long network
+delays.
+Consider a situation where you have two applications, both
+of which normally grab the pointer when clicked on.
+If both applications specify the timestamp from the event,
+the second application may wake up faster and successfully grab the pointer
+before the first application.
+The first application then will get an indication that the other application
+grabbed the pointer before its request was processed.
+</para>
+<para>
+<!-- .LP -->
+<function>XGrabPointer</function>
+generates
+<symbol>EnterNotify</symbol>
+and
+<symbol>LeaveNotify</symbol>
+events.
+</para>
+<para>
+<!-- .LP -->
+Either if grab_window or confine_to window is not viewable
+or if the confine_to window lies completely outside the boundaries of the root
+window,
+<function>XGrabPointer</function>
+fails and returns
+<symbol>GrabNotViewable</symbol>.
+If the pointer is actively grabbed by some other client,
+it fails and returns
+<symbol>AlreadyGrabbed</symbol>.
+If the pointer is frozen by an active grab of another client,
+it fails and returns
+<symbol>GrabFrozen</symbol>.
+If the specified time is earlier than the last-pointer-grab time or later
+than the current X server time, it fails and returns
+<symbol>GrabInvalidTime</symbol>.
+Otherwise, the last-pointer-grab time is set to the specified time
+(<symbol>CurrentTime</symbol>
+is replaced by the current X server time).
+</para>
+<para>
+<!-- .LP -->
+<function>XGrabPointer</function>
+can generate
+<errorname>BadCursor</errorname>,
+<errorname>BadValue</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To ungrab the pointer, use
+<function>XUngrabPointer</function>.
+<indexterm><primary>Ungrabbing</primary><secondary>pointer</secondary></indexterm>
+<indexterm><primary>Pointer</primary><secondary>ungrabbing</secondary></indexterm>
+<indexterm significance="preferred"><primary>XUngrabPointer</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xungrabpointer'>
+<funcprototype>
+ <funcdef><function>XUngrabPointer</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Time<parameter> time</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>time</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the time.
+You can pass either a timestamp or
+<symbol>CurrentTime</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUngrabPointer</function>
+function releases the pointer and any queued events
+if this client has actively grabbed the pointer from
+<function>XGrabPointer</function>,
+<function>XGrabButton</function>,
+or from a normal button press.
+<function>XUngrabPointer</function>
+does not release the pointer if the specified
+time is earlier than the last-pointer-grab time or is later than the
+current X server time.
+It also generates
+<symbol>EnterNotify</symbol>
+and
+<symbol>LeaveNotify</symbol>
+events.
+The X server performs an
+<systemitem>UngrabPointer</systemitem>
+request automatically if the event window or confine_to window
+for an active pointer grab becomes not viewable
+or if window reconfiguration causes the confine_to window to lie completely
+outside the boundaries of the root window.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To change an active pointer grab, use
+<function>XChangeActivePointerGrab</function>.
+<indexterm><primary>Pointer</primary><secondary>grabbing</secondary></indexterm>
+<indexterm ><primary>Changing</primary><secondary>pointer grab</secondary></indexterm>
+<indexterm significance="preferred"><primary>XChangeActivePointerGrab</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xchangeactivepointergrab'>
+<funcprototype>
+ <funcdef><function>XChangeActivePointerGrab</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>unsignedint<parameter> event_mask</parameter></paramdef>
+ <paramdef>Cursor<parameter> cursor</parameter></paramdef>
+ <paramdef>Time<parameter> time</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which pointer events are reported to the client.
+The mask is the bitwise inclusive OR of the valid pointer event mask bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>cursor</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the cursor that is to be displayed or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>time</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the time.
+You can pass either a timestamp or
+<symbol>CurrentTime</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XChangeActivePointerGrab</function>
+function changes the specified dynamic parameters if the pointer is actively
+grabbed by the client and if the specified time is no earlier than the
+last-pointer-grab time and no later than the current X server time.
+This function has no effect on the passive parameters of an
+<function>XGrabButton</function>.
+The interpretation of event_mask and cursor is the same as described in
+<function>XGrabPointer</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XChangeActivePointerGrab</function>
+can generate
+<errorname>BadCursor</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To grab a pointer button, use
+<function>XGrabButton</function>.
+<indexterm><primary>Grabbing</primary><secondary>buttons</secondary></indexterm>
+<indexterm><primary>Button</primary><secondary>grabbing</secondary></indexterm>
+<indexterm significance="preferred"><primary>XGrabButton</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgrabbutton'>
+<funcprototype>
+ <funcdef><function>XGrabButton</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>unsignedint<parameter> button</parameter></paramdef>
+ <paramdef>unsignedint<parameter> modifiers</parameter></paramdef>
+ <paramdef>Window<parameter> grab_window</parameter></paramdef>
+ <paramdef>Bool<parameter> owner_events</parameter></paramdef>
+ <paramdef>unsignedint<parameter> event_mask</parameter></paramdef>
+ <paramdef>intpointer_mode,<parameter> keyboard_mode</parameter></paramdef>
+ <paramdef>Window<parameter> confine_to</parameter></paramdef>
+ <paramdef>Cursor<parameter> cursor</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Bu grabbed -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>button</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the pointer button that is to be (Bu or
+<symbol>AnyButton</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>modifiers</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the set of keymasks or
+<symbol>AnyModifier</symbol>.
+The mask is the bitwise inclusive OR of the valid keymask bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>grab_window</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the grab window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>owner_events</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value that indicates whether the pointer
+events are to be reported as usual or reported with respect to the grab window
+if selected by the event mask.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which pointer events are reported to the client.
+The mask is the bitwise inclusive OR of the valid pointer event mask bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pointer_mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies further processing of pointer events.
+You can pass
+<symbol>GrabModeSync</symbol>
+or
+<symbol>GrabModeAsync</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keyboard_mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies further processing of keyboard events.
+You can pass
+<symbol>GrabModeSync</symbol>
+or
+<symbol>GrabModeAsync</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>confine_to</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window to confine the pointer in or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>cursor</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the cursor that is to be displayed or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGrabButton</function>
+function establishes a passive grab.
+In the future,
+the pointer is actively grabbed (as for
+<function>XGrabPointer</function>),
+the last-pointer-grab time is set to the time at which the button was pressed
+(as transmitted in the
+<symbol>ButtonPress</symbol>
+event), and the
+<symbol>ButtonPress</symbol>
+event is reported if all of the following conditions are true:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The pointer is not grabbed, and the specified button is logically pressed
+when the specified modifier keys are logically down,
+and no other buttons or modifier keys are logically down.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The grab_window contains the pointer.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The confine_to window (if any) is viewable.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A passive grab on the same button/key combination does not exist
+on any ancestor of grab_window.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The interpretation of the remaining arguments is as for
+<function>XGrabPointer</function>.
+The active grab is terminated automatically when the logical state of the
+pointer has all buttons released
+(independent of the state of the logical modifier keys).
+</para>
+<para>
+<!-- .LP -->
+Note that the logical state of a device (as seen by client applications)
+may lag the physical state if device event processing is frozen.
+</para>
+<para>
+<!-- .LP -->
+This request overrides all previous grabs by the same client on the same
+button/key combinations on the same window.
+A modifiers of
+<symbol>AnyModifier</symbol>
+is equivalent to issuing the grab request for all
+possible modifier combinations (including the combination of no modifiers).
+It is not required that all modifiers specified have currently assigned
+KeyCodes.
+A button of
+<symbol>AnyButton</symbol>
+is equivalent to
+issuing the request for all possible buttons.
+Otherwise, it is not required that the specified button currently be assigned
+to a physical button.
+</para>
+<para>
+<!-- .LP -->
+If some other client has already issued an
+<function>XGrabButton</function>
+with the same button/key combination on the same window, a
+<errorname>BadAccess</errorname>
+error results.
+When using
+<symbol>AnyModifier</symbol>
+or
+<symbol>AnyButton</symbol>,
+the request fails completely,
+and a
+<errorname>BadAccess</errorname>
+error results (no grabs are
+established) if there is a conflicting grab for any combination.
+<function>XGrabButton</function>
+has no effect on an active grab.
+</para>
+<para>
+<!-- .LP -->
+<function>XGrabButton</function>
+can generate
+<errorname>BadCursor</errorname>,
+<errorname>BadValue</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To ungrab a pointer button, use
+<function>XUngrabButton</function>.
+<indexterm><primary>Ungrabbing</primary><secondary>buttons</secondary></indexterm>
+<indexterm><primary>Button</primary><secondary>ungrabbing</secondary></indexterm>
+<indexterm significance="preferred"><primary>XUngrabButton</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xungrabbutton'>
+<funcprototype>
+ <funcdef><function>XUngrabButton</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>unsignedint<parameter> button</parameter></paramdef>
+ <paramdef>unsignedint<parameter> modifiers</parameter></paramdef>
+ <paramdef>Window<parameter> grab_window</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Bu released -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>button</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the pointer button that is to be (Bu or
+<symbol>AnyButton</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>modifiers</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the set of keymasks or
+<symbol>AnyModifier</symbol>.
+The mask is the bitwise inclusive OR of the valid keymask bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>grab_window</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the grab window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUngrabButton</function>
+function releases the passive button/key combination on the specified window if
+it was grabbed by this client.
+A modifiers of
+<symbol>AnyModifier</symbol>
+is
+equivalent to issuing
+the ungrab request for all possible modifier combinations, including
+the combination of no modifiers.
+A button of
+<symbol>AnyButton</symbol>
+is equivalent to issuing the
+request for all possible buttons.
+<function>XUngrabButton</function>
+has no effect on an active grab.
+</para>
+<para>
+<!-- .LP -->
+<function>XUngrabButton</function>
+can generate
+<errorname>BadValue</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect1>
+<sect1 id="Keyboard_Grabbing_">
+<title>Keyboard Grabbing </title>
+<!-- .XS -->
+<!-- (SN Keyboard Grabbing -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to grab or ungrab the keyboard
+as well as allow events.
+</para>
+<para>
+<!-- .LP -->
+For many functions in this section,
+you pass keymask bits.
+The valid keymask bits are:
+<symbol>ShiftMask</symbol>,
+<symbol>LockMask</symbol>,
+<symbol>ControlMask</symbol>,
+<symbol>Mod1Mask</symbol>,
+<symbol>Mod2Mask</symbol>,
+<symbol>Mod3Mask</symbol>,
+<symbol>Mod4Mask</symbol>,
+and
+<symbol>Mod5Mask</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To grab the keyboard, use
+<function>XGrabKeyboard</function>.
+<indexterm><primary>Keyboard</primary><secondary>grabbing</secondary></indexterm>
+<indexterm><primary>Grabbing</primary><secondary>keyboard</secondary></indexterm>
+<indexterm significance="preferred"><primary>XGrabKeyboard</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgrabkeyboard'>
+<funcprototype>
+ <funcdef>int <function>XGrabKeyboard</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> grab_window</parameter></paramdef>
+ <paramdef>Bool<parameter> owner_events</parameter></paramdef>
+ <paramdef>intpointer_mode,<parameter> keyboard_mode</parameter></paramdef>
+ <paramdef>Time<parameter> time</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>grab_window</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the grab window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>owner_events</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value that indicates whether the keyboard events
+are to be reported as usual.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pointer_mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies further processing of pointer events.
+You can pass
+<symbol>GrabModeSync</symbol>
+or
+<symbol>GrabModeAsync</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keyboard_mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies further processing of keyboard events.
+You can pass
+<symbol>GrabModeSync</symbol>
+or
+<symbol>GrabModeAsync</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>time</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the time.
+You can pass either a timestamp or
+<symbol>CurrentTime</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGrabKeyboard</function>
+function actively grabs control of the keyboard and generates
+<symbol>FocusIn</symbol>
+and
+<symbol>FocusOut</symbol>
+events.
+Further key events are reported only to the
+grabbing client.
+<function>XGrabKeyboard</function>
+overrides any active keyboard grab by this client.
+If owner_events is
+<symbol>False</symbol>,
+all generated key events are reported with
+respect to grab_window.
+If owner_events is
+<symbol>True</symbol>
+and if a generated
+key event would normally be reported to this client, it is reported
+normally; otherwise, the event is reported with respect to the
+grab_window.
+Both
+<symbol>KeyPress</symbol>
+and
+<symbol>KeyRelease</symbol>
+events are always reported,
+independent of any event selection made by the client.
+</para>
+<para>
+<!-- .LP -->
+If the keyboard_mode argument is
+<symbol>GrabModeAsync</symbol>,
+keyboard event processing continues
+as usual.
+If the keyboard is currently frozen by this client,
+then processing of keyboard events is resumed.
+If the keyboard_mode argument is
+<symbol>GrabModeSync</symbol>,
+the state of the keyboard (as seen by client applications) appears to freeze,
+and the X server generates no further keyboard events until the
+grabbing client issues a releasing
+<function>XAllowEvents</function>
+call or until the keyboard grab is released.
+Actual keyboard changes are not lost while the keyboard is frozen;
+they are simply queued in the server for later processing.
+</para>
+<para>
+<!-- .LP -->
+If pointer_mode is
+<symbol>GrabModeAsync</symbol>,
+pointer event processing is unaffected
+by activation of the grab.
+If pointer_mode is
+<symbol>GrabModeSync</symbol>,
+the state of the pointer (as seen by client applications) appears to freeze,
+and the X server generates no further pointer events
+until the grabbing client issues a releasing
+<function>XAllowEvents</function>
+call or until the keyboard grab is released.
+Actual pointer changes are not lost while the pointer is frozen;
+they are simply queued in the server for later processing.
+</para>
+<para>
+<!-- .LP -->
+If the keyboard is actively grabbed by some other client,
+<function>XGrabKeyboard</function>
+fails and returns
+<symbol>AlreadyGrabbed</symbol>.
+If grab_window is not viewable,
+it fails and returns
+<symbol>GrabNotViewable</symbol>.
+If the keyboard is frozen by an active grab of another client,
+it fails and returns
+<symbol>GrabFrozen</symbol>.
+If the specified time is earlier than the last-keyboard-grab time
+or later than the current X server time,
+it fails and returns
+<symbol>GrabInvalidTime</symbol>.
+Otherwise, the last-keyboard-grab time is set to the specified time
+(<symbol>CurrentTime</symbol>
+is replaced by the current X server time).
+</para>
+<para>
+<!-- .LP -->
+<function>XGrabKeyboard</function>
+can generate
+<errorname>BadValue</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To ungrab the keyboard, use
+<function>XUngrabKeyboard</function>.
+<indexterm><primary>Keyboard</primary><secondary>ungrabbing</secondary></indexterm>
+<indexterm><primary>Ungrabbing</primary><secondary>keyboard</secondary></indexterm>
+<indexterm significance="preferred"><primary>XUngrabKeyboard</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xungrabkeyboard'>
+<funcprototype>
+ <funcdef><function>XUngrabKeyboard</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Time<parameter> time</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>time</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the time.
+You can pass either a timestamp or
+<symbol>CurrentTime</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUngrabKeyboard</function>
+function
+releases the keyboard and any queued events if this client has it actively grabbed from
+either
+<function>XGrabKeyboard</function>
+or
+<function>XGrabKey</function>.
+<function>XUngrabKeyboard</function>
+does not release the keyboard and any queued events
+if the specified time is earlier than
+the last-keyboard-grab time or is later than the current X server time.
+It also generates
+<symbol>FocusIn</symbol>
+and
+<symbol>FocusOut</symbol>
+events.
+The X server automatically performs an
+<systemitem>UngrabKeyboard</systemitem>
+request if the event window for an
+active keyboard grab becomes not viewable.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To passively grab a single key of the keyboard, use
+<function>XGrabKey</function>.
+<indexterm><primary>Key</primary><secondary>grabbing</secondary></indexterm>
+<indexterm><primary>Grabbing</primary><secondary>keys</secondary></indexterm>
+<indexterm significance="preferred"><primary>XGrabKey</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgrabkey'>
+<funcprototype>
+ <funcdef><function>XGrabKey</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> keycode</parameter></paramdef>
+ <paramdef>unsignedint<parameter> modifiers</parameter></paramdef>
+ <paramdef>Window<parameter> grab_window</parameter></paramdef>
+ <paramdef>Bool<parameter> owner_events</parameter></paramdef>
+ <paramdef>intpointer_mode,<parameter> keyboard_mode</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keycode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeyCode or
+<symbol>AnyKey</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>modifiers</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the set of keymasks or
+<symbol>AnyModifier</symbol>.
+The mask is the bitwise inclusive OR of the valid keymask bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>grab_window</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the grab window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>owner_events</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value that indicates whether the keyboard events
+are to be reported as usual.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pointer_mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies further processing of pointer events.
+You can pass
+<symbol>GrabModeSync</symbol>
+or
+<symbol>GrabModeAsync</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keyboard_mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies further processing of keyboard events.
+You can pass
+<symbol>GrabModeSync</symbol>
+or
+<symbol>GrabModeAsync</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGrabKey</function>
+function establishes a passive grab on the keyboard.
+In the future,
+the keyboard is actively grabbed (as for
+<function>XGrabKeyboard</function>),
+the last-keyboard-grab time is set to the time at which the key was pressed
+(as transmitted in the
+<symbol>KeyPress</symbol>
+event), and the
+<symbol>KeyPress</symbol>
+event is reported if all of the following conditions are true:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The keyboard is not grabbed and the specified key
+(which can itself be a modifier key) is logically pressed
+when the specified modifier keys are logically down,
+and no other modifier keys are logically down.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Either the grab_window is an ancestor of (or is) the focus window,
+or the grab_window is a descendant of the focus window and contains the pointer.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A passive grab on the same key combination does not exist
+on any ancestor of grab_window.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The interpretation of the remaining arguments is as for
+<function>XGrabKeyboard</function>.
+The active grab is terminated automatically when the logical state of the
+keyboard has the specified key released
+(independent of the logical state of the modifier keys).
+</para>
+<para>
+<!-- .LP -->
+Note that the logical state of a device (as seen by client applications)
+may lag the physical state if device event processing is frozen.
+</para>
+<para>
+<!-- .LP -->
+A modifiers argument of
+<symbol>AnyModifier</symbol>
+is equivalent to issuing the request for all
+possible modifier combinations (including the combination of no
+modifiers).
+It is not required that all modifiers specified have
+currently assigned KeyCodes.
+A keycode argument of
+<symbol>AnyKey</symbol>
+is equivalent to issuing
+the request for all possible KeyCodes.
+Otherwise, the specified keycode must be in
+the range specified by min_keycode and max_keycode in the connection
+setup,
+or a
+<errorname>BadValue</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+If some other client has issued a
+<function>XGrabKey</function>
+with the same key combination on the same window, a
+<errorname>BadAccess</errorname>
+error results.
+When using
+<symbol>AnyModifier</symbol>
+or
+<symbol>AnyKey</symbol>,
+the request fails completely,
+and a
+<errorname>BadAccess</errorname>
+error results (no grabs are established)
+if there is a conflicting grab for any combination.
+</para>
+<para>
+<!-- .LP -->
+<function>XGrabKey</function>
+can generate
+<errorname>BadAccess</errorname>,
+<errorname>BadValue</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To ungrab a key, use
+<function>XUngrabKey</function>.
+<indexterm><primary>Key</primary><secondary>ungrabbing</secondary></indexterm>
+<indexterm><primary>Ungrabbing</primary><secondary>keys</secondary></indexterm>
+<indexterm significance="preferred"><primary>XUngrabKey</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xungrabkey'>
+<funcprototype>
+ <funcdef><function>XUngrabKey</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> keycode</parameter></paramdef>
+ <paramdef>unsignedint<parameter> modifiers</parameter></paramdef>
+ <paramdef>Window<parameter> grab_window</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keycode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeyCode or
+<symbol>AnyKey</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>modifiers</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the set of keymasks or
+<symbol>AnyModifier</symbol>.
+The mask is the bitwise inclusive OR of the valid keymask bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>grab_window</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the grab window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUngrabKey</function>
+function releases the key combination on the specified window if it was grabbed
+by this client.
+It has no effect on an active grab.
+A modifiers of
+<symbol>AnyModifier</symbol>
+is equivalent to issuing
+the request for all possible modifier combinations
+(including the combination of no modifiers).
+A keycode argument of
+<symbol>AnyKey</symbol>
+is equivalent to issuing the request for all possible key codes.
+</para>
+<para>
+<!-- .LP -->
+<function>XUngrabKey</function>
+can generate
+<errorname>BadValue</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect1>
+<sect1 id="Resuming_Event_Processing">
+<title>Resuming Event Processing</title>
+<!-- .XS -->
+<!-- (SN Resuming Event Processing -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The previous sections discussed grab mechanisms with which processing
+of events by the server can be temporarily suspended. This section
+describes the mechanism for resuming event processing.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To allow further events to be processed when the device has been frozen, use
+<function>XAllowEvents</function>.
+<indexterm significance="preferred"><primary>XAllowEvents</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xallowevents'>
+<funcprototype>
+ <funcdef><function>XAllowEvents</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> event_mode</parameter></paramdef>
+ <paramdef>Time<parameter> time</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the event mode.
+You can pass
+<symbol>AsyncPointer</symbol>,
+<symbol>SyncPointer</symbol>,
+<symbol>AsyncKeyboard</symbol>,
+<symbol>SyncKeyboard</symbol>,
+<symbol>ReplayPointer</symbol>,
+<symbol>ReplayKeyboard</symbol>,
+<symbol>AsyncBoth</symbol>,
+or
+<symbol>SyncBoth</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>time</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the time.
+You can pass either a timestamp or
+<symbol>CurrentTime</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAllowEvents</function>
+function releases some queued events if the client has caused a device
+to freeze.
+It has no effect if the specified time is earlier than the last-grab
+time of the most recent active grab for the client or if the specified time
+is later than the current X server time.
+Depending on the event_mode argument, the following occurs:
+</para>
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <tbody>
+ <row>
+ <entry><symbol>AsyncPointer</symbol></entry>
+ <entry>If the pointer is frozen by the client,
+ pointer event processing continues as usual.
+ If the pointer is frozen twice by the client on behalf of two separate grabs,
+ <symbol>AsyncPointer</symbol>
+ thaws for both.
+ <symbol>AsyncPointer</symbol>
+ has no effect if the pointer is not frozen by the client,
+ but the pointer need not be grabbed by the client.</entry>
+ </row>
+ <row>
+ <entry><symbol>SyncPointer</symbol></entry>
+ <entry>If the pointer is frozen and actively grabbed by the client,
+ pointer event processing continues as usual until the next
+ <symbol>ButtonPress</symbol>
+ or
+ <symbol>ButtonRelease</symbol>
+ event is reported to the client.
+ At this time,
+ the pointer again appears to freeze.
+ However, if the reported event causes the pointer grab to be released,
+ the pointer does not freeze.
+ <symbol>SyncPointer</symbol>
+ has no effect if the pointer is not frozen by the client
+ or if the pointer is not grabbed by the client.</entry>
+ </row>
+ <row>
+ <entry><symbol>ReplayPointer</symbol></entry>
+ <entry>If the pointer is actively grabbed by the client and is frozen as the result of
+ an event having been sent to the client (either from the activation of an
+ <function>XGrabButton</function>
+ or from a previous
+ <function>XAllowEvents</function>
+ with mode
+ <symbol>SyncPointer</symbol>
+ but not from an
+ <function>XGrabPointer</function>),
+ the pointer grab is released and that event is completely reprocessed.
+ This time, however, the function ignores any passive grabs at or above
+ (toward the root of) the grab_window of the grab just released.
+ The request has no effect if the pointer is not grabbed by the client
+ or if the pointer is not frozen as the result of an event.</entry>
+ </row>
+ <row>
+ <entry><symbol>AsyncKeyboard</symbol></entry>
+ <entry>If the keyboard is frozen by the client,
+ keyboard event processing continues as usual.
+ If the keyboard is frozen twice by the client on behalf of two separate grabs,
+ <symbol>AsyncKeyboard</symbol>
+ thaws for both.
+ <symbol>AsyncKeyboard</symbol>
+ has no effect if the keyboard is not frozen by the client,
+ but the keyboard need not be grabbed by the client.</entry>
+ </row>
+ <row>
+ <entry><symbol>SyncKeyboard</symbol></entry>
+ <entry>If the keyboard is frozen and actively grabbed by the client,
+ keyboard event processing continues as usual until the next
+ <symbol>KeyPress</symbol>
+ or
+ <symbol>KeyRelease</symbol>
+ event is reported to the client.
+ At this time,
+ the keyboard again appears to freeze.
+ However, if the reported event causes the keyboard grab to be released,
+ the keyboard does not freeze.
+ <symbol>SyncKeyboard</symbol>
+ has no effect if the keyboard is not frozen by the client
+ or if the keyboard is not grabbed by the client.</entry>
+ </row>
+ <row>
+ <entry><symbol>ReplayKeyboard</symbol></entry>
+ <entry>If the keyboard is actively grabbed by the client and is frozen
+ as the result of an event having been sent to the client (either from the
+ activation of an
+ <function>XGrabKey</function>
+ or from a previous
+ <function>XAllowEvents</function>
+ with mode
+ <symbol>SyncKeyboard</symbol>
+ but not from an
+ <function>XGrabKeyboard</function>),
+ the keyboard grab is released and that event is completely reprocessed.
+ This time, however, the function ignores any passive grabs at or above
+ (toward the root of)
+ the grab_window of the grab just released.
+ The request has no effect if the keyboard is not grabbed by the client
+ or if the keyboard is not frozen as the result of an event.</entry>
+ </row>
+ <row>
+ <entry><symbol>SyncBoth</symbol></entry>
+ <entry>If both pointer and keyboard are frozen by the client,
+ event processing for both devices continues as usual until the next
+ <symbol>ButtonPress</symbol>,
+ <symbol>ButtonRelease</symbol>,
+ <symbol>KeyPress</symbol>,
+ or
+ <symbol>KeyRelease</symbol>
+ event is reported to the client for a grabbed device
+ (button event for the pointer, key event for the keyboard),
+ at which time the devices again appear to freeze.
+ However, if the reported event causes the grab to be released,
+ then the devices do not freeze (but if the other device is still
+ grabbed, then a subsequent event for it will still cause both devices
+ to freeze).
+ <symbol>SyncBoth</symbol>
+ has no effect unless both pointer and keyboard
+ are frozen by the client.
+ If the pointer or keyboard is frozen twice
+ by the client on behalf of two separate grabs,
+ <symbol>SyncBoth</symbol>
+ thaws for both (but a subsequent freeze for
+ <symbol>SyncBoth</symbol>
+ will only freeze each device once).</entry>
+ </row>
+ <row>
+ <entry><symbol>AsyncBoth</symbol></entry>
+ <entry>If the pointer and the keyboard are frozen by the
+ client, event processing for both devices continues as usual.
+ If a device is frozen twice by the client on behalf of two separate grabs,
+ <symbol>AsyncBoth</symbol>
+ thaws for both.
+ <symbol>AsyncBoth</symbol>
+ has no effect unless both
+ pointer and keyboard are frozen by the client.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+<symbol>AsyncPointer</symbol>,
+<symbol>SyncPointer</symbol>,
+and
+<symbol>ReplayPointer</symbol>
+have no effect on the
+processing of keyboard events.
+<symbol>AsyncKeyboard</symbol>,
+<symbol>SyncKeyboard</symbol>,
+and
+<symbol>ReplayKeyboard</symbol>
+have no effect on the
+processing of pointer events.
+It is possible for both a pointer grab and a keyboard grab (by the same
+or different clients) to be active simultaneously.
+If a device is frozen on behalf of either grab,
+no event processing is performed for the device.
+It is possible for a single device to be frozen because of both grabs.
+In this case,
+the freeze must be released on behalf of both grabs before events can
+again be processed.
+If a device is frozen twice by a single client,
+then a single
+<function>XAllowEvents</function>
+releases both.
+</para>
+<para>
+<!-- .LP -->
+<function>XAllowEvents</function>
+can generate a
+<errorname>BadValue</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Moving_the_Pointer">
+<title>Moving the Pointer</title>
+<!-- .XS -->
+<!-- (SN Moving the Pointer -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Although movement of the pointer normally should be left to the
+control of the end user, sometimes it is necessary to move the
+pointer to a new position under program control.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To move the pointer to an arbitrary point in a window, use
+<function>XWarpPointer</function>.
+<indexterm significance="preferred"><primary>XWarpPointer</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xwarppointer'>
+<funcprototype>
+ <funcdef><function>XWarpPointer</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Windowsrc_w,<parameter> dest_w</parameter></paramdef>
+ <paramdef>intsrc_x,<parameter> src_y</parameter></paramdef>
+ <paramdef>unsignedintsrc_width,<parameter> src_height</parameter></paramdef>
+ <paramdef>intdest_x,<parameter> dest_y</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src_w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the source window or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the destination window or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src_x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src_y</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src_width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src_height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify a rectangle in the source window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates within the destination window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If dest_w is
+<symbol>None</symbol>,
+<function>XWarpPointer</function>
+moves the pointer by the offsets (dest_x, dest_y) relative to the current
+position of the pointer.
+If dest_w is a window,
+<function>XWarpPointer</function>
+moves the pointer to the offsets (dest_x, dest_y) relative to the origin of
+dest_w.
+However, if src_w is a window,
+the move only takes place if the window src_w contains the pointer
+and if the specified rectangle of src_w contains the pointer.
+</para>
+<para>
+<!-- .LP -->
+The src_x and src_y coordinates are relative to the origin of src_w.
+If src_height is zero,
+it is replaced with the current height of src_w minus src_y.
+If src_width is zero,
+it is replaced with the current width of src_w minus src_x.
+</para>
+<para>
+<!-- .LP -->
+There is seldom any reason for calling this function.
+The pointer should normally be left to the user.
+If you do use this function, however, it generates events just as if the user
+had instantaneously moved the pointer from one position to another.
+Note that you cannot use
+<function>XWarpPointer</function>
+to move the pointer outside the confine_to window of an active pointer grab.
+An attempt to do so will only move the pointer as far as the closest edge of the
+confine_to window.
+</para>
+<para>
+<!-- .LP -->
+<function>XWarpPointer</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect1>
+<sect1 id="Controlling_Input_Focus">
+<title>Controlling Input Focus</title>
+<!-- .XS -->
+<!-- (SN Controlling Input Focus -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set and get the input focus.
+The input focus is a shared resource, and cooperation among clients is
+required for correct interaction. See the
+<emphasis remap='I'>Inter-Client Communication Conventions Manual</emphasis>
+for input focus policy.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the input focus, use
+<function>XSetInputFocus</function>.
+<indexterm significance="preferred"><primary>XSetInputFocus</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetinputfocus'>
+<funcprototype>
+ <funcdef><function>XSetInputFocus</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> focus</parameter></paramdef>
+ <paramdef>int<parameter> revert_to</parameter></paramdef>
+ <paramdef>Time<parameter> time</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>focus</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window,
+<symbol>PointerRoot</symbol>,
+or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>revert_to</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies where the input focus reverts to if the window becomes not
+viewable.
+You can pass
+<symbol>RevertToParent</symbol>,
+<symbol>RevertToPointerRoot</symbol>,
+or
+<symbol>RevertToNone</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>time</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the time.
+You can pass either a timestamp or
+<symbol>CurrentTime</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetInputFocus</function>
+function changes the input focus and the last-focus-change time.
+It has no effect if the specified time is earlier than the current
+last-focus-change time or is later than the current X server time.
+Otherwise, the last-focus-change time is set to the specified time
+(<symbol>CurrentTime</symbol>
+is replaced by the current X server time).
+<function>XSetInputFocus</function>
+causes the X server to generate
+<symbol>FocusIn</symbol>
+and
+<symbol>FocusOut</symbol>
+events.
+</para>
+<para>
+<!-- .LP -->
+Depending on the focus argument,
+the following occurs:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+If focus is
+<symbol>None</symbol>,
+all keyboard events are discarded until a new focus window is set,
+and the revert_to argument is ignored.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If focus is a window,
+it becomes the keyboard's focus window.
+If a generated keyboard event would normally be reported to this window
+or one of its inferiors, the event is reported as usual.
+Otherwise, the event is reported relative to the focus window.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If focus is
+<symbol>PointerRoot</symbol>,
+the focus window is dynamically taken to be the root window of whatever screen
+the pointer is on at each keyboard event.
+In this case, the revert_to argument is ignored.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The specified focus window must be viewable at the time
+<function>XSetInputFocus</function>
+is called,
+or a
+<errorname>BadMatch</errorname>
+error results.
+If the focus window later becomes not viewable,
+the X server
+evaluates the revert_to argument to determine the new focus window as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+If revert_to is
+<symbol>RevertToParent</symbol>,
+the focus reverts to the parent (or the closest viewable ancestor),
+and the new revert_to value is taken to be
+<symbol>RevertToNone</symbol>.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If revert_to is
+<symbol>RevertToPointerRoot</symbol>
+or
+<symbol>RevertToNone</symbol>,
+the focus reverts to
+<symbol>PointerRoot</symbol>
+or
+<symbol>None</symbol>,
+respectively.
+When the focus reverts,
+the X server generates
+<symbol>FocusIn</symbol>
+and
+<symbol>FocusOut</symbol>
+events, but the last-focus-change time is not affected.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+<function>XSetInputFocus</function>
+can generate
+<errorname>BadMatch</errorname>,
+<errorname>BadValue</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the current input focus, use
+<function>XGetInputFocus</function>.
+<indexterm significance="preferred"><primary>XGetInputFocus</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetinputfocus'>
+<funcprototype>
+ <funcdef><function>XGetInputFocus</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> *focus_return</parameter></paramdef>
+ <paramdef>int<parameter> *revert_to_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>focus_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the focus window,
+<symbol>PointerRoot</symbol>,
+or
+<symbol>None</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>revert_to_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the current focus state
+(<symbol>RevertToParent</symbol>,
+<symbol>RevertToPointerRoot</symbol>,
+or
+<symbol>RevertToNone</symbol>).
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetInputFocus</function>
+function returns the focus window and the current focus state.
+</para>
+</sect1>
+<sect1 id="Manipulating_the_Keyboard_and_Pointer_Settings">
+<title>Manipulating the Keyboard and Pointer Settings</title>
+<!-- .XS -->
+<!-- (SN Manipulating the Keyboard and Pointer Settings -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to
+change the keyboard control, obtain a list of the auto-repeat keys,
+turn keyboard auto-repeat on or off, ring the bell,
+set or obtain the pointer button or keyboard mapping,
+and obtain a bit vector for the keyboard.
+</para>
+<para>
+<!-- .LP -->
+<indexterm><primary>Keyboard</primary><secondary>bell volume</secondary></indexterm>
+<indexterm><primary>Keyboard</primary><secondary>keyclick volume</secondary></indexterm>
+<indexterm><primary>Keyboard</primary><secondary>bit vector</secondary></indexterm>
+<indexterm><primary>Mouse</primary><secondary>programming</secondary></indexterm>
+This section discusses
+the user-preference options of bell, key click,
+pointer behavior, and so on.
+The default values for many of these options are server dependent.
+Not all implementations will actually be able to control all of these
+parameters.
+</para>
+<para>
+<!-- .LP -->
+The
+<function>XChangeKeyboardControl</function>
+function changes control of a keyboard and operates on a
+<structname>XKeyboardControl</structname>
+structure:
+<!-- .sM -->
+</para>
+
+<literallayout class="monospaced">
+/* Mask bits for ChangeKeyboardControl */
+
+
+#define KBBellPercent (1L&lt;&lt;0)
+#define KBBellPitch (1L&lt;&lt;1)
+#define KBBellDuration (1L&lt;&lt;2)
+#define KBLed (1L&lt;&lt;3)
+#define KBLedMode (1L&lt;&lt;4)
+#define KBKey (1L&lt;&lt;5)
+#define KBAutoRepeatMode (1L&lt;&lt;6)
+
+
+/* Values */
+
+typedef struct {
+int key_click_percent;
+int bell_percent;
+int bell_pitch;
+int bell_duration;
+int led;
+int led_mode; /* LedModeOn, LedModeOff */
+int key;
+int auto_repeat_mode; /* AutoRepeatModeOff, AutoRepeatModeOn,
+ AutoRepeatModeDefault */
+} XKeyboardControl;
+
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The key_click_percent member sets the volume for key clicks between 0 (off)
+and 100 (loud) inclusive, if possible.
+A setting of -1 restores the default.
+Other negative values generate a
+<errorname>BadValue</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+The bell_percent sets the base volume for the bell between 0 (off) and 100
+(loud) inclusive, if possible.
+A setting of -1 restores the default.
+Other negative values generate a
+<errorname>BadValue</errorname>
+error.
+The bell_pitch member sets the pitch (specified in Hz) of the bell, if possible.
+A setting of -1 restores the default.
+Other negative values generate a
+<errorname>BadValue</errorname>
+error.
+The bell_duration member sets the duration of the
+bell specified in milliseconds, if possible.
+A setting of -1 restores the default.
+Other negative values generate a
+<errorname>BadValue</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+If both the led_mode and led members are specified,
+the state of that <acronym>LED</acronym> is changed, if possible.
+The led_mode member can be set to
+<symbol>LedModeOn</symbol>
+or
+<symbol>LedModeOff</symbol>.
+If only led_mode is specified, the state of
+all LEDs are changed, if possible.
+At most 32 LEDs numbered from one are supported.
+No standard interpretation of LEDs is defined.
+If led is specified without led_mode, a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+If both the auto_repeat_mode and key members are specified,
+the auto_repeat_mode of that key is changed (according to
+<symbol>AutoRepeatModeOn</symbol>,
+<symbol>AutoRepeatModeOff</symbol>,
+or
+<symbol>AutoRepeatModeDefault</symbol>),
+if possible.
+If only auto_repeat_mode is
+specified, the global auto_repeat_mode for the entire keyboard is
+changed, if possible, and does not affect the per-key settings.
+If a key is specified without an auto_repeat_mode, a
+<errorname>BadMatch</errorname>
+error results.
+Each key has an individual mode of whether or not it should auto-repeat
+and a default setting for the mode.
+In addition,
+there is a global mode of whether auto-repeat should be enabled or not
+and a default setting for that mode.
+When global mode is
+<symbol>AutoRepeatModeOn</symbol>,
+keys should obey their individual auto-repeat modes.
+When global mode is
+<symbol>AutoRepeatModeOff</symbol>,
+no keys should auto-repeat.
+An auto-repeating key generates alternating
+<symbol>KeyPress</symbol>
+and
+<symbol>KeyRelease</symbol>
+events.
+When a key is used as a modifier,
+it is desirable for the key not to auto-repeat,
+regardless of its auto-repeat setting.
+</para>
+<para>
+<!-- .LP -->
+A bell generator connected with the console but not directly on a
+keyboard is treated as if it were part of the keyboard.
+The order in which controls are verified and altered is server-dependent.
+If an error is generated, a subset of the controls may have been altered.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+<indexterm significance="preferred"><primary>XChangeKeyboardControl</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xchangekeyboardcontrol'>
+<funcprototype>
+ <funcdef><function>XChangeKeyboardControl</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> value_mask</parameter></paramdef>
+ <paramdef>XKeyboardControl<parameter> *values</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which controls to change.
+This mask is the bitwise inclusive OR of the valid control mask bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>values</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies one value for each bit set to 1 in the mask.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XChangeKeyboardControl</function>
+function controls the keyboard characteristics defined by the
+<structname>XKeyboardControl</structname>
+structure.
+The value_mask argument specifies which values are to be changed.
+</para>
+<para>
+<!-- .LP -->
+<function>XChangeKeyboardControl</function>
+can generate
+<errorname>BadMatch</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the current control values for the keyboard, use
+<function>XGetKeyboardControl</function>.
+<indexterm significance="preferred"><primary>XGetKeyboardControl</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetkeyboardcontrol'>
+<funcprototype>
+ <funcdef><function>XGetKeyboardControl</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XKeyboardState<parameter> *values_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>values_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the current keyboard controls in the specified
+<structname>XKeyboardState</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetKeyboardControl</function>
+function returns the current control values for the keyboard to the
+<structname>XKeyboardState</structname>
+structure.
+</para>
+<para>
+<!-- .LP -->
+<indexterm><primary>XGetKeyboardControl</primary></indexterm>
+<indexterm significance="preferred"><primary>XKeyboardState</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i -->
+<!-- .ta .5i -->
+typedef struct {
+ int key_click_percent;
+ int bell_percent;
+ unsigned int bell_pitch, bell_duration;
+ unsigned long led_mask;
+ int global_auto_repeat;
+ char auto_repeats[32];
+} XKeyboardState;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+For the LEDs,
+the least significant bit of led_mask corresponds to <acronym>LED</acronym> one,
+and each bit set to 1 in led_mask indicates an <acronym>LED</acronym> that is lit.
+The global_auto_repeat member can be set to
+<symbol>AutoRepeatModeOn</symbol>
+or
+<symbol>AutoRepeatModeOff</symbol>.
+The auto_repeats member is a bit vector.
+Each bit set to 1 indicates that auto-repeat is enabled
+for the corresponding key.
+The vector is represented as 32 bytes.
+Byte N (from 0) contains the bits for keys 8N to 8N + 7
+with the least significant bit in the byte representing key 8N.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To turn on keyboard auto-repeat, use
+<function>XAutoRepeatOn</function>.
+<indexterm significance="preferred"><primary>XAutoRepeatOn</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xautorepeaton'>
+<funcprototype>
+ <funcdef><function>XAutoRepeatOn</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAutoRepeatOn</function>
+function turns on auto-repeat for the keyboard on the specified display.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To turn off keyboard auto-repeat, use
+<function>XAutoRepeatOff</function>.
+<indexterm significance="preferred"><primary>XAutoRepeatOff</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xautorepeatoff'>
+<funcprototype>
+ <funcdef><function>XAutoRepeatOff</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAutoRepeatOff</function>
+function turns off auto-repeat for the keyboard on the specified display.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To ring the bell, use
+<function>XBell</function>.
+<indexterm significance="preferred"><primary>XBell</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xbell'>
+<funcprototype>
+ <funcdef><function>XBell</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> percent</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>percent</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the volume for the bell,
+which can range from -100 to 100 inclusive.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XBell</function>
+function rings the bell on the keyboard on the specified display, if possible.
+The specified volume is relative to the base volume for the keyboard.
+If the value for the percent argument is not in the range -100 to 100
+inclusive, a
+<errorname>BadValue</errorname>
+error results.
+The volume at which the bell rings
+when the percent argument is nonnegative is:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+base - [(base * percent) / 100] + percent
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The volume at which the bell rings
+when the percent argument is negative is:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+base + [(base * percent) / 100]
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+To change the base volume of the bell, use
+<function>XChangeKeyboardControl</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XBell</function>
+can generate a
+<errorname>BadValue</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain a bit vector that describes the state of the keyboard, use
+<function>XQueryKeymap</function>.
+<indexterm significance="preferred"><primary>XQueryKeymap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xquerykeymap'>
+<funcprototype>
+ <funcdef><function>XQueryKeymap</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> keys_return[32]</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keys_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns an array of bytes that identifies which keys are pressed down.
+Each bit represents one key of the keyboard.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XQueryKeymap</function>
+function returns a bit vector for the logical state of the keyboard,
+where each bit set to 1 indicates that the corresponding key is currently
+pressed down.
+The vector is represented as 32 bytes.
+Byte N (from 0) contains the bits for keys 8N to 8N + 7
+with the least significant bit in the byte representing key 8N.
+</para>
+<para>
+<!-- .LP -->
+Note that the logical state of a device (as seen by client applications)
+may lag the physical state if device event processing is frozen.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the mapping of the pointer buttons, use
+<function>XSetPointerMapping</function>.
+<indexterm significance="preferred"><primary>XSetPointerMapping</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetpointermapping'>
+<funcprototype>
+ <funcdef>int <function>XSetPointerMapping</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>unsignedchar<parameter> map[]</parameter></paramdef>
+ <paramdef>int<parameter> nmap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>map</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the mapping list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nmap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of items in the mapping list.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetPointerMapping</function>
+function sets the mapping of the pointer.
+If it succeeds, the X server generates a
+<symbol>MappingNotify</symbol>
+event, and
+<function>XSetPointerMapping</function>
+returns
+<symbol>MappingSuccess</symbol>.
+Element map[i] defines the logical button number for the physical button
+i+1.
+The length of the list must be the same as
+<function>XGetPointerMapping</function>
+would return,
+or a
+<errorname>BadValue</errorname>
+error results.
+A zero element disables a button, and elements are not restricted in
+value by the number of physical buttons.
+However, no two elements can have the same nonzero value,
+or a
+<errorname>BadValue</errorname>
+error results.
+If any of the buttons to be altered are logically in the down state,
+<function>XSetPointerMapping</function>
+returns
+<symbol>MappingBusy</symbol>,
+and the mapping is not changed.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetPointerMapping</function>
+can generate a
+<errorname>BadValue</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To get the pointer mapping, use
+<function>XGetPointerMapping</function>.
+<indexterm significance="preferred"><primary>XGetPointerMapping</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetpointermapping'>
+<funcprototype>
+ <funcdef>int <function>XGetPointerMapping</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>unsignedchar<parameter> map_return[]</parameter></paramdef>
+ <paramdef>int<parameter> nmap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>map_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the mapping list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nmap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of items in the mapping list.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetPointerMapping</function>
+function returns the current mapping of the pointer.
+Pointer buttons are numbered starting from one.
+<function>XGetPointerMapping</function>
+returns the number of physical buttons actually on the pointer.
+The nominal mapping for a pointer is map[i]=i+1.
+The nmap argument specifies the length of the array where the pointer
+mapping is returned, and only the first nmap elements are returned
+in map_return.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To control the pointer's interactive feel, use
+<function>XChangePointerControl</function>.
+<indexterm significance="preferred"><primary>XChangePointerControl</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xchangepointercontrol'>
+<funcprototype>
+ <funcdef><function>XChangePointerControl</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Booldo_accel,<parameter> do_threshold</parameter></paramdef>
+ <paramdef>intaccel_numerator,<parameter> accel_denominator</parameter></paramdef>
+ <paramdef>int<parameter> threshold</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>do_accel</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value that controls whether the values for
+the accel_numerator or accel_denominator are used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>do_threshold</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a Boolean value that controls whether the value for the
+threshold is used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>accel_numerator</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the numerator for the acceleration multiplier.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>accel_denominator</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the denominator for the acceleration multiplier.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>threshold</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the acceleration threshold.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XChangePointerControl</function>
+function defines how the pointing device moves.
+The acceleration, expressed as a fraction, is a
+multiplier for movement.
+For example,
+specifying 3/1 means the pointer moves three times as fast as normal.
+The fraction may be rounded arbitrarily by the X server.
+Acceleration
+only takes effect if the pointer moves more than threshold pixels at
+once and only applies to the amount beyond the value in the threshold argument.
+Setting a value to -1 restores the default.
+The values of the do_accel and do_threshold arguments must be
+<symbol>True</symbol>
+for the pointer values to be set,
+or the parameters are unchanged.
+Negative values (other than -1) generate a
+<errorname>BadValue</errorname>
+error, as does a zero value
+for the accel_denominator argument.
+</para>
+<para>
+<!-- .LP -->
+<function>XChangePointerControl</function>
+can generate a
+<errorname>BadValue</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To get the current pointer parameters, use
+<function>XGetPointerControl</function>.
+<indexterm significance="preferred"><primary>XGetPointerControl</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetpointercontrol'>
+<funcprototype>
+ <funcdef><function>XGetPointerControl</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int*accel_numerator_return,<parameter> *accel_denominator_return</parameter></paramdef>
+ <paramdef>int<parameter> *threshold_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>accel_numerator_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the numerator for the acceleration multiplier.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>accel_denominator_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the denominator for the acceleration multiplier.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>threshold_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the acceleration threshold.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetPointerControl</function>
+function returns the pointer's current acceleration multiplier
+and acceleration threshold.
+</para>
+</sect1>
+<sect1 id="Manipulating_the_Keyboard_Encoding">
+<title>Manipulating the Keyboard Encoding</title>
+<!-- .XS -->
+<!-- (SN Manipulating the Keyboard Encoding -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+A KeyCode represents a physical (or logical) key.
+KeyCodes lie in the inclusive range [8,255].
+A KeyCode value carries no intrinsic information,
+although server implementors may attempt to encode geometry
+(for example, matrix) information in some fashion so that it can
+be interpreted in a server-dependent fashion.
+The mapping between keys and KeyCodes cannot be changed.
+</para>
+<para>
+<!-- .LP -->
+A KeySym is an encoding of a symbol on the cap of a key.
+The set of defined KeySyms includes the ISO Latin character sets (1-4),
+Katakana, Arabic, Cyrillic, Greek, Technical,
+Special, Publishing, APL, Hebrew, Thai, Korean
+and a miscellany of keys found
+on keyboards (Return, Help, Tab, and so on).
+To the extent possible, these sets are derived from international
+standards.
+In areas where no standards exist,
+some of these sets are derived from Digital Equipment Corporation standards.
+The list of defined symbols can be found in
+<filename class="headerfile">&lt;X11/keysymdef.h&gt;</filename>.
+<indexterm type="file"><primary><filename class="headerfile">X11/keysymdef.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/keysymdef.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/keysymdef.h&gt;</filename></secondary></indexterm>
+Unfortunately, some C preprocessors have
+limits on the number of defined symbols.
+If you must use KeySyms not
+in the Latin 1-4, Greek, and miscellaneous classes,
+you may have to define a symbol for those sets.
+Most applications usually only include
+<filename class="headerfile">&lt;X11/keysym.h&gt;</filename>,
+<indexterm type="file"><primary><filename class="headerfile">X11/keysym.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/keysym.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/keysym.h&gt;</filename></secondary></indexterm>
+which defines symbols for ISO Latin 1-4, Greek, and miscellaneous.
+</para>
+<para>
+<!-- .LP -->
+A list of KeySyms is associated with each KeyCode.
+The list is intended to convey the set of symbols on the corresponding key.
+If the list (ignoring trailing
+<symbol>NoSymbol</symbol>
+entries) is
+a single KeySym ``<emphasis remap='I'>K</emphasis>'',
+then the list is treated as if it were the list
+``<emphasis remap='I'>K</emphasis> NoSymbol <emphasis remap='I'>K</emphasis> NoSymbol''.
+If the list (ignoring trailing
+<symbol>NoSymbol</symbol>
+entries) is a pair of KeySyms ``<emphasis remap='I'>K1 K2</emphasis>'',
+then the list is treated as if it were the list ``<emphasis remap='I'>K1 K2 K1 K2</emphasis>''.
+If the list (ignoring trailing
+<symbol>NoSymbol</symbol>
+entries) is a triple of KeySyms ``<emphasis remap='I'>K1 K2 K3</emphasis>'',
+then the list is treated as if it were the list ``<emphasis remap='I'>K1 K2 K3</emphasis> NoSymbol''.
+When an explicit ``void'' element is desired in the list,
+the value
+<symbol>VoidSymbol</symbol>
+can be used.
+</para>
+<para>
+<!-- .LP -->
+The first four elements of the list are split into two groups of KeySyms.
+Group 1 contains the first and second KeySyms;
+Group 2 contains the third and fourth KeySyms.
+Within each group,
+if the second element of the group is
+<symbol>NoSymbol</symbol>,
+then the group should be treated as if the second element were
+the same as the first element,
+except when the first element is an alphabetic KeySym ``<emphasis remap='I'>K</emphasis>''
+for which both lowercase and uppercase forms are defined.
+In that case,
+the group should be treated as if the first element were
+the lowercase form of ``<emphasis remap='I'>K</emphasis>'' and the second element were
+the uppercase form of ``<emphasis remap='I'>K</emphasis>''.
+</para>
+<para>
+<!-- .LP -->
+The standard rules for obtaining a KeySym from a
+<symbol>KeyPress</symbol>
+event make use of only the Group 1 and Group 2 KeySyms;
+no interpretation of other KeySyms in the list is given.
+Which group to use is determined by the modifier state.
+Switching between groups is controlled by the KeySym named MODE SWITCH,
+by attaching that KeySym to some KeyCode and attaching
+that KeyCode to any one of the modifiers
+<symbol>Mod1</symbol>
+through
+<symbol>Mod5</symbol>.
+This modifier is called the <emphasis remap='I'>group modifier</emphasis>.
+For any KeyCode,
+Group 1 is used when the group modifier is off,
+and Group 2 is used when the group modifier is on.
+</para>
+<para>
+<!-- .LP -->
+The
+<symbol>Lock</symbol>
+modifier is interpreted as CapsLock when the KeySym named XK_Caps_Lock
+is attached to some KeyCode and that KeyCode is attached to the
+<symbol>Lock</symbol>
+modifier. The
+<symbol>Lock</symbol>
+modifier is interpreted as ShiftLock when the KeySym named XK_Shift_Lock
+is attached to some KeyCode and that KeyCode is attached to the
+<symbol>Lock</symbol>
+modifier. If the
+<symbol>Lock</symbol>
+modifier could be interpreted as both
+CapsLock and ShiftLock, the CapsLock interpretation is used.
+</para>
+<para>
+<!-- .LP -->
+The operation of keypad keys is controlled by the KeySym named XK_Num_Lock,
+by attaching that KeySym to some KeyCode and attaching that KeyCode to any
+one of the modifiers
+<symbol>Mod1</symbol>
+through
+<symbol>Mod5</symbol>.
+This modifier is called the
+<emphasis remap='I'>numlock modifier</emphasis>. The standard KeySyms with the prefix ``XK_KP_''
+in their
+name are called keypad KeySyms; these are KeySyms with numeric value in
+the hexadecimal range 0xFF80 to 0xFFBD inclusive. In addition,
+vendor-specific KeySyms in the hexadecimal range 0x11000000 to 0x1100FFFF
+are also keypad KeySyms.
+</para>
+<para>
+<!-- .LP -->
+Within a group, the choice of KeySym is determined by applying the first
+rule that is satisfied from the following list:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The numlock modifier is on and the second KeySym is a keypad KeySym. In
+this case, if the
+<symbol>Shift</symbol>
+modifier is on, or if the
+<symbol>Lock</symbol>
+modifier is on and
+is interpreted as ShiftLock, then the first KeySym is used, otherwise the
+second KeySym is used.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The
+<symbol>Shift</symbol>
+and
+<symbol>Lock</symbol>
+modifiers are both off. In this case, the first
+KeySym is used.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The
+<symbol>Shift</symbol>
+modifier is off, and the
+<symbol>Lock</symbol>
+modifier is on and is
+interpreted as CapsLock. In this case, the first KeySym is used, but if
+that KeySym is lowercase alphabetic, then the corresponding uppercase
+KeySym is used instead.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The
+<symbol>Shift</symbol>
+modifier is on, and the
+<symbol>Lock</symbol>
+modifier is on and is interpreted
+as CapsLock. In this case, the second KeySym is used, but if that KeySym
+is lowercase alphabetic, then the corresponding uppercase KeySym is used
+instead.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The
+<symbol>Shift</symbol>
+modifier is on, or the
+<symbol>Lock</symbol>
+modifier is on and is interpreted
+as ShiftLock, or both. In this case, the second KeySym is used.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+No spatial geometry of the symbols on the key is defined by
+their order in the KeySym list,
+although a geometry might be defined on a
+server-specific basis.
+The X server does not use the mapping between KeyCodes and KeySyms.
+Rather, it merely stores it for reading and writing by clients.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the legal KeyCodes for a display, use
+<function>XDisplayKeycodes</function>.
+<indexterm significance="preferred"><primary>XDisplayKeycodes</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdisplaykeycodes'>
+<funcprototype>
+ <funcdef><function>XDisplayKeycodes</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int*min_keycodes_return,<parameter> *max_keycodes_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>min_keycodes_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the minimum number of KeyCodes.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>max_keycodes_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the maximum number of KeyCodes.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDisplayKeycodes</function>
+function returns the min-keycodes and max-keycodes supported by the
+specified display.
+The minimum number of KeyCodes returned is never less than 8,
+and the maximum number of KeyCodes returned is never greater than 255.
+Not all KeyCodes in this range are required to have corresponding keys.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the symbols for the specified KeyCodes, use
+<function>XGetKeyboardMapping</function>.
+<indexterm significance="preferred"><primary>XGetKeyboardMapping</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetkeyboardmapping'>
+<funcprototype>
+ <funcdef>KeySym *<function>XGetKeyboardMapping</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>KeyCode<parameter> first_keycode</parameter></paramdef>
+ <paramdef>int<parameter> keycode_count</parameter></paramdef>
+ <paramdef>int<parameter> *keysyms_per_keycode_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Kc returned -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>first_keycode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the first KeyCode that is to be (Kc.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keycode_count</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of KeyCodes that are to be returned.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysyms_per_keycode_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of KeySyms per KeyCode.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetKeyboardMapping</function>
+function returns the symbols for the specified number of KeyCodes
+starting with first_keycode.
+The value specified in first_keycode must be greater than
+or equal to min_keycode as returned by
+<function>XDisplayKeycodes</function>,
+or a
+<errorname>BadValue</errorname>
+error results.
+In addition, the following expression must be less than or equal
+to max_keycode as returned by
+<function>XDisplayKeycodes</function>:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+first_keycode + keycode_count - 1
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+If this is not the case, a
+<errorname>BadValue</errorname>
+error results.
+The number of elements in the KeySyms list is:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+keycode_count * keysyms_per_keycode_return
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+KeySym number N, counting from zero, for KeyCode K has the following index
+in the list, counting from zero:
+<literallayout class="monospaced">
+(K - first_code) * keysyms_per_code_return + N
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The X server arbitrarily chooses the keysyms_per_keycode_return value
+to be large enough to report all requested symbols.
+A special KeySym value of
+<symbol>NoSymbol</symbol>
+is used to fill in unused elements for
+individual KeyCodes.
+To free the storage returned by
+<function>XGetKeyboardMapping</function>,
+use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetKeyboardMapping</function>
+can generate a
+<errorname>BadValue</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To change the keyboard mapping, use
+<function>XChangeKeyboardMapping</function>.
+<indexterm significance="preferred"><primary>XChangeKeyboardMapping</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xchangekeyboardmapping'>
+<funcprototype>
+ <funcdef><function>XChangeKeyboardMapping</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> first_keycode</parameter></paramdef>
+ <paramdef>int<parameter> keysyms_per_keycode</parameter></paramdef>
+ <paramdef>KeySym<parameter> *keysyms</parameter></paramdef>
+ <paramdef>int<parameter> num_codes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Kc changed -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>first_keycode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the first KeyCode that is to be (Kc.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysyms_per_keycode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of KeySyms per KeyCode.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysyms</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of KeySyms.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_codes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of KeyCodes that are to be changed.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XChangeKeyboardMapping</function>
+function defines the symbols for the specified number of KeyCodes
+starting with first_keycode.
+The symbols for KeyCodes outside this range remain unchanged.
+The number of elements in keysyms must be:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+num_codes * keysyms_per_keycode
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The specified first_keycode must be greater than or equal to min_keycode
+returned by
+<function>XDisplayKeycodes</function>,
+or a
+<errorname>BadValue</errorname>
+error results.
+In addition, the following expression must be less than or equal to
+max_keycode as returned by
+<function>XDisplayKeycodes</function>,
+or a
+<errorname>BadValue</errorname>
+error results:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+first_keycode + num_codes - 1
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+KeySym number N, counting from zero, for KeyCode K has the following index
+in keysyms, counting from zero:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+(K - first_keycode) * keysyms_per_keycode + N
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The specified keysyms_per_keycode can be chosen arbitrarily by the client
+to be large enough to hold all desired symbols.
+A special KeySym value of
+<symbol>NoSymbol</symbol>
+should be used to fill in unused elements
+for individual KeyCodes.
+It is legal for
+<symbol>NoSymbol</symbol>
+to appear in nontrailing positions
+of the effective list for a KeyCode.
+<function>XChangeKeyboardMapping</function>
+generates a
+<symbol>MappingNotify</symbol>
+event.
+</para>
+<para>
+<!-- .LP -->
+There is no requirement that the X server interpret this mapping.
+It is merely stored for reading and writing by clients.
+</para>
+<para>
+<!-- .LP -->
+<function>XChangeKeyboardMapping</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+The next six functions make use of the
+<structname>XModifierKeymap</structname>
+data structure, which contains:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XModifierKeymap</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ int max_keypermod; /* This server's max number of keys per modifier */
+ KeyCode *modifiermap; /* An 8 by max_keypermod array of the modifiers */
+} XModifierKeymap;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+To create an
+<structname>XModifierKeymap</structname>
+structure, use
+<function>XNewModifiermap</function>.
+<indexterm significance="preferred"><primary>XNewModifiermap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xnewmodifiermap'>
+<funcprototype>
+ <funcdef>XModifierKeymap *<function>XNewModifiermap</function></funcdef>
+ <paramdef>int<parameter> max_keys_per_mod</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>max_keys_per_mod</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of KeyCode entries preallocated to the modifiers
+in the map.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XNewModifiermap</function>
+function returns a pointer to
+<structname>XModifierKeymap</structname>
+structure for later use.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To add a new entry to an
+<structname>XModifierKeymap</structname>
+structure, use
+<function>XInsertModifiermapEntry</function>.
+<indexterm significance="preferred"><primary>XInsertModifiermapEntry</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xinsertmodifiermapentry'>
+<funcprototype>
+ <funcdef>XModifierKeymap *<function>XInsertModifiermapEntry</function></funcdef>
+ <paramdef>XModifierKeymap<parameter> *modmap</parameter></paramdef>
+ <paramdef>KeyCode<parameter> keycode_entry</parameter></paramdef>
+ <paramdef>int<parameter> modifier</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>modmap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XModifierKeymap</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keycode_entry</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeyCode.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>modifier</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the modifier.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XInsertModifiermapEntry</function>
+function adds the specified KeyCode to the set that controls the specified
+modifier and returns the resulting
+<structname>XModifierKeymap</structname>
+structure (expanded as needed).
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To delete an entry from an
+<structname>XModifierKeymap</structname>
+structure, use
+<function>XDeleteModifiermapEntry</function>.
+<indexterm significance="preferred"><primary>XDeleteModifiermapEntry</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdeletemodifiermapentry'>
+<funcprototype>
+ <funcdef>XModifierKeymap *<function>XDeleteModifiermapEntry</function></funcdef>
+ <paramdef>XModifierKeymap<parameter> *modmap</parameter></paramdef>
+ <paramdef>KeyCode<parameter> keycode_entry</parameter></paramdef>
+ <paramdef>int<parameter> modifier</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>modmap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XModifierKeymap</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keycode_entry</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeyCode.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>modifier</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the modifier.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDeleteModifiermapEntry</function>
+function deletes the specified KeyCode from the set that controls the
+specified modifier and returns a pointer to the resulting
+<structname>XModifierKeymap</structname>
+structure.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To destroy an
+<structname>XModifierKeymap</structname>
+structure, use
+<function>XFreeModifiermap</function>.
+<indexterm significance="preferred"><primary>XFreeModifiermap</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfreemodifiermap'>
+<funcprototype>
+ <funcdef><function>XFreeModifiermap</function></funcdef>
+ <paramdef>XModifierKeymap<parameter> *modmap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>modmap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XModifierKeymap</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreeModifiermap</function>
+function frees the specified
+<structname>XModifierKeymap</structname>
+structure.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the KeyCodes to be used as modifiers, use
+<function>XSetModifierMapping</function>.
+<indexterm significance="preferred"><primary>XSetModifierMapping</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetmodifiermapping'>
+<funcprototype>
+ <funcdef>int <function>XSetModifierMapping</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XModifierKeymap<parameter> *modmap</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>modmap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XModifierKeymap</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetModifierMapping</function>
+function specifies the KeyCodes of the keys (if any) that are to be used
+as modifiers.
+If it succeeds,
+the X server generates a
+<symbol>MappingNotify</symbol>
+event, and
+<function>XSetModifierMapping</function>
+returns
+<symbol>MappingSuccess</symbol>.
+X permits at most 8 modifier keys.
+If more than 8 are specified in the
+<structname>XModifierKeymap</structname>
+structure, a
+<errorname>BadLength</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+The modifiermap member of the
+<structname>XModifierKeymap</structname>
+structure contains 8 sets of max_keypermod KeyCodes,
+one for each modifier in the order
+<symbol>Shift</symbol>,
+<symbol>Lock</symbol>,
+<symbol>Control</symbol>,
+<symbol>Mod1</symbol>,
+<symbol>Mod2</symbol>,
+<symbol>Mod3</symbol>,
+<symbol>Mod4</symbol>,
+and
+<symbol>Mod5</symbol>.
+Only nonzero KeyCodes have meaning in each set,
+and zero KeyCodes are ignored.
+In addition, all of the nonzero KeyCodes must be in the range specified by
+min_keycode and max_keycode in the
+<type>Display</type>
+structure,
+or a
+<errorname>BadValue</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+An X server can impose restrictions on how modifiers can be changed,
+for example,
+if certain keys do not generate up transitions in hardware,
+if auto-repeat cannot be disabled on certain keys,
+or if multiple modifier keys are not supported.
+If some such restriction is violated,
+the status reply is
+<symbol>MappingFailed</symbol>,
+and none of the modifiers are changed.
+If the new KeyCodes specified for a modifier differ from those
+currently defined and any (current or new) keys for that modifier are
+in the logically down state,
+<function>XSetModifierMapping</function>
+returns
+<symbol>MappingBusy</symbol>,
+and none of the modifiers is changed.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetModifierMapping</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the KeyCodes used as modifiers, use
+<function>XGetModifierMapping</function>.
+<indexterm significance="preferred"><primary>XGetModifierMapping</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetmodifiermapping'>
+<funcprototype>
+ <funcdef>XModifierKeymap *<function>XGetModifierMapping</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetModifierMapping</function>
+function returns a pointer to a newly created
+<structname>XModifierKeymap</structname>
+structure that contains the keys being used as modifiers.
+The structure should be freed after use by calling
+<function>XFreeModifiermap</function>.
+If only zero values appear in the set for any modifier,
+that modifier is disabled.
+<!-- .bp -->
+
+
+</para>
+</sect1>
+</chapter>
diff --git a/libX11/specs/libX11/CH13.xml b/libX11/specs/libX11/CH13.xml
index e28b1b0f3..4219fa981 100644
--- a/libX11/specs/libX11/CH13.xml
+++ b/libX11/specs/libX11/CH13.xml
@@ -1,10353 +1,10353 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<chapter id="locales_and_internationalized_text_functions">
-<title>Locales and Internationalized Text Functions</title>
-
-<para>
-An internationalized application is one that is adaptable to the requirements of different native
-languages, local customs, and character string encodings. The process of adapting the operation
-to a particular native language, local custom, or string encoding is called localization. A goal of
-internationalization is to permit localization without program source modifications or recompilation.
-</para>
-<para>
-As one of the localization mechanisms, Xlib provides an X Input Method (<acronym>XIM</acronym>)
-functional interface for internationalized text input and an X Output Method
-(<acronym>XOM</acronym>) functional interface for internationalized text output.
-</para>
-<para>
-Internationalization in X is based on the concept of a locale. A locale defines the localized
-behavior of a program at run time. Locales affect Xlib in its:
-</para>
-
-<itemizedlist>
- <listitem><para>Encoding and processing of input method text</para></listitem>
- <listitem><para>Encoding of resource files and values</para></listitem>
- <listitem><para>Encoding and imaging of text strings</para></listitem>
- <listitem><para>Encoding and decoding for inter-client text communication</para></listitem>
-</itemizedlist>
-
-
-<para>
-•
-Encoding and decoding for inter-client text communication
-Characters from various languages are represented in a computer using an encoding.
-Different languages have different encodings, and there are even different
-encodings for the same characters in the same language.
-</para>
-<para>
-This chapter defines support for localized text imaging and text input and describes the locale
-mechanism that controls all locale-dependent Xlib functions. Sets of functions are provided for
-multibyte (char *) text as well as wide character (wchar_t) text in the form supported by the host
-C language environment. The multibyte and wide character functions are equivalent except for
-the form of the text argument.
-</para>
-<para>
-The Xlib internationalization functions are not meant to provide support for
-multilingual applications (mixing multiple languages within a single piece of text),
-but they make it possible to implement applications that work in limited
-fashion with more than one language in independent contexts.
-</para>
-<para>
-The remainder of this chapter discusses:
-</para>
-
-<itemizedlist>
- <listitem><para>X locale management</para></listitem>
- <listitem><para>Locale and modifier dependencies</para></listitem>
- <listitem><para>Variable argument lists</para></listitem>
- <listitem><para>Output methods</para></listitem>
- <listitem><para>Input methods</para></listitem>
- <listitem><para>String constants</para></listitem>
-</itemizedlist>
-
-
-<sect1 id="X_Locale_Management">
-<title>X Locale Management</title>
-<!-- .XS -->
-<!-- (SN X Locale Management -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-X supports one or more of the locales defined by the host environment.
-On implementations that conform to the ANSI C library,
-the locale announcement method is
-<function>setlocale</function>.
-This function configures the locale operation of both
-the host C library and Xlib.
-The operation of Xlib is governed by the LC_CTYPE category;
-this is called the <emphasis remap='I'>current locale</emphasis>.
-An implementation is permitted to provide implementation-dependent
-mechanisms for announcing the locale in addition to
-<function>setlocale</function>.
-</para>
-<para>
-<!-- .LP -->
-On implementations that do not conform to the ANSI C library,
-the locale announcement method is Xlib implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-The mechanism by which the semantic operation of Xlib is defined
-for a specific locale is implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-X is not required to support all the locales supported by the host.
-To determine if the current locale is supported by X, use
-<function>XSupportsLocale</function>.
-</para>
-
-<para>Bool XSupportsLocale()</para>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSupportsLocale</function>
-function returns
-<symbol>True</symbol>
-if Xlib functions are capable of operating under the current locale.
-If it returns
-<symbol>False</symbol>,
-Xlib locale-dependent functions for which the
-<symbol>XLocaleNotSupported</symbol>
-return status is defined will return
-<symbol>XLocaleNotSupported</symbol>.
-Other Xlib locale-dependent routines will operate in the ``C'' locale.
-</para>
-<para>
-<!-- .LP -->
-The client is responsible for selecting its locale and X modifiers.
-Clients should provide a means for the user to override the clients'
-locale selection at client invocation.
-Most single-display X clients operate in a single locale
-for both X and the host processing environment.
-They will configure the locale by calling three functions:
-the host locale configuration function,
-<function>XSupportsLocale</function>,
-and
-<function>XSetLocaleModifiers</function>.
-</para>
-<para>
-<!-- .LP -->
-The semantics of certain categories of X internationalization capabilities
-can be configured by setting modifiers.
-Modifiers are named by implementation-dependent and locale-specific strings.
-The only standard use for this capability at present
-is selecting one of several styles of keyboard input method.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To configure Xlib locale modifiers for the current locale, use
-<function>XSetLocaleModifiers</function>.
-<indexterm significance="preferred"><primary>XSetLocaleModifiers</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XSetLocaleModifiers</function></funcdef>
- <paramdef>char<parameter> *modifier_list</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>modifier_list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the modifiers.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetLocaleModifiers</function>
-function sets the X modifiers for the current locale setting.
-The modifier_list argument is a null-terminated string of the form
-``{@<emphasis remap='I'>category</emphasis>=<emphasis remap='I'>value</emphasis>}'', that is,
-having zero or more concatenated ``@<emphasis remap='I'>category</emphasis>=<emphasis remap='I'>value</emphasis>''
-entries, where <emphasis remap='I'>category</emphasis> is a category name
-and <emphasis remap='I'>value</emphasis> is the (possibly empty) setting for that category.
-The values are encoded in the current locale.
-Category names are restricted to the <acronym>POSIX</acronym> Portable Filename Character Set.
-</para>
-<para>
-<!-- .LP -->
-The local host X locale modifiers announcer (on <acronym>POSIX</acronym>-compliant systems,
-the XMODIFIERS environment variable) is appended to the modifier_list to
-provide default values on the local host.
-If a given category appears more than once in the list,
-the first setting in the list is used.
-If a given category is not included in the full modifier list,
-the category is set to an implementation-dependent default
-for the current locale.
-An empty value for a category explicitly specifies the
-implementation-dependent default.
-</para>
-<para>
-<!-- .LP -->
-If the function is successful, it returns a pointer to a string.
-The contents of the string are such that a subsequent call with that string
-(in the same locale) will restore the modifiers to the same settings.
-If modifier_list is a NULL pointer,
-<function>XSetLocaleModifiers</function>
-also returns a pointer to such a string,
-and the current locale modifiers are not changed.
-</para>
-<para>
-<!-- .LP -->
-If invalid values are given for one or more modifier categories supported by
-the locale, a NULL pointer is returned, and none of the
-current modifiers are changed.
-</para>
-<para>
-<!-- .LP -->
-At program startup,
-the modifiers that are in effect are unspecified until
-the first successful call to set them. Whenever the locale is changed, the
-modifiers that are in effect become unspecified until the next successful call
-to set them.
-Clients should always call
-<function>XSetLocaleModifiers</function>
-with a non-NULL modifier_list after setting the locale
-before they call any locale-dependent Xlib routine.
-</para>
-<para>
-<!-- .LP -->
-The only standard modifier category currently defined is ``im'',
-which identifies the desired input method.
-The values for input method are not standardized.
-A single locale may use multiple input methods,
-switching input method under user control.
-The modifier may specify the initial input method in effect
-or an ordered list of input methods.
-Multiple input methods may be specified in a single im value string
-in an implementation-dependent manner.
-</para>
-<para>
-<!-- .LP -->
-The returned modifiers string is owned by Xlib and should not be modified or
-freed by the client.
-It may be freed by Xlib after the current locale or modifiers are changed.
-Until freed, it will not be modified by Xlib.
-</para>
-<para>
-<!-- .LP -->
-The recommended procedure for clients initializing their locale and modifiers
-is to obtain locale and modifier announcers separately from
-one of the following prioritized sources:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-A command line option
- </para>
- </listitem>
- <listitem>
- <para>
-A resource
- </para>
- </listitem>
- <listitem>
- <para>
-The empty string ("")
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The first of these that is defined should be used.
-Note that when a locale command line option or locale resource is defined,
-the effect should be to set all categories to the specified locale,
-overriding any category-specific settings in the local host environment.
-</para>
-</sect1>
-<sect1 id="Locale_and_Modifier_Dependencies">
-<title>Locale and Modifier Dependencies</title>
-<!-- .XS -->
-<!-- (SN Locale and Modifier Dependencies -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The internationalized Xlib functions operate in the current locale
-configured by the host environment and X locale modifiers set by
-<function>XSetLocaleModifiers</function>
-or in the locale and modifiers configured at the time
-some object supplied to the function was created.
-For each locale-dependent function,
-the following table describes the locale (and modifiers) dependency:
-</para>
-
-<informaltable>
- <tgroup cols='3' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <thead>
- <row>
- <entry>Locale from</entry>
- <entry>Affects the Function</entry>
- <entry>In</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry></entry>
- <entry>Locale Query/Configuration:</entry>
- </row>
- <row>
- <entry><function>setlocale</function></entry>
- <entry><function>XSupportsLocale</function></entry>
- <entry>Locale queried</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XSetLocaleModifiers</function></entry>
- <entry>Locale modified</entry>
- </row>
- <row>
- <entry></entry>
- </row>
- <row>
- <entry></entry>
- <entry>Resources:</entry>
- </row>
- <row>
- <entry><function>setlocale</function></entry>
- <entry><function>XrmGetFileDatabase</function></entry>
- <entry>Locale of <type>XrmDatabase</type></entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XrmGetStringDatabase</function></entry>
- </row>
- <row>
- <entry><type>XrmDatabase</type></entry>
- <entry><function>XrmPutFileDatabase</function></entry>
- <entry>Locale of <type>XrmDatabase</type></entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XrmLocaleOfDatabase</function></entry>
- </row>
- <row>
- <entry></entry>
- </row>
- <row>
- <entry></entry>
- <entry>Setting Standard Properties:</entry>
- </row>
- <row>
- <entry><function>setlocale</function></entry>
- <entry><function>XmbSetWMProperties</function></entry>
- <entry>Encoding of supplied/returned
- text (some WM_ property
- text in environment locale)</entry>
- </row>
- <row>
- <entry><function>setlocale</function></entry>
- <entry><function>XmbTextPropertyToTextList</function></entry>
- <entry>Encoding of supplied/returned text</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XwcTextPropertyToTextList</function></entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XmbTextListToTextProperty</function></entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XwcTextListToTextProperty</function></entry>
- </row>
- <row>
- <entry></entry>
- </row>
- <row>
- <entry></entry>
- <entry>Text Input:</entry>
- </row>
- <row>
- <entry><function>setlocale</function></entry>
- <entry><function>XOpenIM</function></entry>
- <entry><acronym>XIM</acronym> input method selection</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XRegisterIMInstantiateCallback</function></entry>
- <entry><acronym>XIM</acronym> selection</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XUnregisterIMInstantiateCallback</function></entry>
- <entry><acronym>XIM</acronym> selection</entry>
- </row>
- <row>
- <entry><type>XIM</type></entry>
- <entry><function>XCreateIC</function></entry>
- <entry><acronym>XIC</acronym> input method configuration</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XLocaleOfIM</function>, and so on</entry>
- <entry>Queried locale</entry>
- </row>
- <row>
- <entry><type>XIC</type></entry>
- <entry><function>XmbLookupString</function></entry>
- <entry>Keyboard layout</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XwcLookupString</function></entry>
- <entry>Encoding of returned text</entry>
- </row>
- <row>
- <entry></entry>
- </row>
- <row>
- <entry></entry>
- <entry>Text Drawing:</entry>
- </row>
- <row>
- <entry><function>setlocale</function></entry>
- <entry><function>XOpenOM</function></entry>
- <entry><acronym>XOM</acronym> output method selection</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XCreateFontSet</function></entry>
- <entry>Charsets of fonts in XFontSet</entry>
- </row>
- <row>
- <entry><type>XOM</type></entry>
- <entry><function>XCreateOC</function></entry>
- <entry><acronym>XOC</acronym> output method configuration</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XLocaleOfOM</function>, and so on</entry>
- <entry>Queried locale</entry>
- </row>
- <row>
- <entry><type>XFontSet</type></entry>
- <entry><function>XmbDrawText</function>,</entry>
- <entry>Locale of supplied text</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XwcDrawText</function>, and so on</entry>
- <entry>Locale of supplied text</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XExtentsOfFontSet</function>, and so on</entry>
- <entry>Locale-dependent metrics</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XmbTextExtents</function>,</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XwcTextExtents</function>, and so on</entry>
- </row>
- <row>
- <entry></entry>
- </row>
- <row>
- <entry></entry>
- <entry>Xlib Errors:</entry>
- </row>
- <row>
- <entry><function>setlocale</function></entry>
- <entry><function>XGetErrorDatabaseText</function></entry>
- <entry>Locale of error message</entry>
- </row>
- <row>
- <entry></entry>
- <entry><function>XGetErrorText</function></entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-Clients may assume that a locale-encoded text string returned
-by an X function can be passed to a C library routine, or vice versa,
-if the locale is the same at the two calls.
-</para>
-<para>
-<!-- .LP -->
-All text strings processed by internationalized Xlib functions are assumed
-to begin in the initial state of the encoding of the locale, if the encoding
-is state-dependent.
-</para>
-<para>
-<!-- .LP -->
-All Xlib functions behave as if they do not change the current locale
-or X modifier setting.
-(This means that if they do change locale or call
-<function>XSetLocaleModifiers</function>
-with a non-NULL argument, they must save and restore the current state on
-entry and exit.)
-Also, Xlib functions on implementations that conform to the ANSI C library do
-not alter the global state associated with the ANSI C functions
-<function>mblen</function>,
-<function>mbtowc</function>,
-<function>wctomb</function>,
-and
-<function>strtok</function>.
-</para>
-</sect1>
-<sect1 id="Variable_Argument_Lists">
-<title>Variable Argument Lists</title>
-<!-- .XS -->
-<!-- (SN Variable Argument Lists -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Various functions in this chapter have arguments that conform
-to the ANSI C variable argument list calling convention.
-Each function denoted with an argument of the form ``...'' takes
-a variable-length list of name and value pairs,
-where each name is a string and each value is of type
-<type>XPointer</type>.
-A name argument that is NULL identifies the end of the list.
-</para>
-<para>
-<!-- .LP -->
-A variable-length argument list may contain a nested list.
-If the name
-<symbol>XNVaNestedList</symbol>
-is specified in place of an argument name,
-then the following value is interpreted as an
-<type>XVaNestedList</type>
-value that specifies a list of values logically inserted into the
-original list at the point of declaration.
-A NULL identifies the end of a nested list.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To allocate a nested variable argument list dynamically, use
-<function>XVaCreateNestedList</function>.
-<indexterm significance="preferred"><primary>XVaCreateNestedList</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XVaNestedList <function>XVaCreateNestedList</function></funcdef>
- <paramdef>int<parameter> dummy</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>dummy</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an unused argument (required by ANSI C).
-<!-- .ds Al -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- ...
- </term>
- <listitem>
- <para>
-Specifies the variable length argument list(Al.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XVaCreateNestedList</function>
-function allocates memory and copies its arguments into
-a single list pointer,
-which may be used as a value for arguments requiring a list value.
-Any entries are copied as specified.
-Data passed by reference is not copied;
-the caller must ensure data remains valid for the lifetime
-of the nested list.
-The list should be freed using
-<function>XFree</function>
-when it is no longer needed.
-</para>
-</sect1>
-<sect1 id="Output_Methods">
-<title>Output Methods</title>
-<!-- .XS -->
-<!-- (SN Output Methods -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This section provides discussions of the following X Output Method
-(<acronym>XOM</acronym>) topics:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Output method overview
- </para>
- </listitem>
- <listitem>
- <para>
-Output method functions
- </para>
- </listitem>
- <listitem>
- <para>
-Output method values
- </para>
- </listitem>
- <listitem>
- <para>
-Output context functions
- </para>
- </listitem>
- <listitem>
- <para>
-Output context values
- </para>
- </listitem>
- <listitem>
- <para>
-Creating and freeing a font set
- </para>
- </listitem>
- <listitem>
- <para>
-Obtaining font set metrics
- </para>
- </listitem>
- <listitem>
- <para>
-Drawing text using font sets
- </para>
- </listitem>
-</itemizedlist>
-<sect2 id="Output_Method_Overview">
-<title>Output Method Overview</title>
-<!-- .XS -->
-<!-- (SN Output Method Overview -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Locale-dependent text may include one or more text components, each of
-which may require different fonts and character set encodings.
-In some languages, each component might have a different
-drawing direction, and some components might contain
-context-dependent characters that change shape based on
-relationships with neighboring characters.
-</para>
-<para>
-<!-- .LP -->
-When drawing such locale-dependent text, some locale-specific
-knowledge is required;
-for example, what fonts are required to draw the text,
-how the text can be separated into components, and which
-fonts are selected to draw each component.
-Further, when bidirectional text must be drawn,
-the internal representation order of the text must be changed
-into the visual representation order to be drawn.
-</para>
-<para>
-<!-- .LP -->
-An X Output Method provides a functional interface so that clients
-do not have to deal directly with such locale-dependent details.
-Output methods provide the following capabilities:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Creating a set of fonts required to draw locale-dependent text.
- </para>
- </listitem>
- <listitem>
- <para>
-Drawing locale-dependent text with a font set without the caller
-needing to be aware of locale dependencies.
- </para>
- </listitem>
- <listitem>
- <para>
-Obtaining the escapement and extents in pixels of locale-dependent text.
- </para>
- </listitem>
- <listitem>
- <para>
-Determining if bidirectional or context-dependent drawing is required
-in a specific locale with a specific font set.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Two different abstractions are used in the representation of
-the output method for clients.
-</para>
-<para>
-<!-- .LP -->
-The abstraction used to communicate with an output method
-is an opaque data structure represented by the
-<type>XOM</type>
-data type.
-The abstraction for representing the state of a particular output thread
-is called an <emphasis remap='I'>output context</emphasis>.
-The Xlib representation of an output context is an
-<type>XOC</type>,
-which is compatible with
-<type>XFontSet</type>
-in terms of its functional interface, but is
-a broader, more generalized abstraction.
-</para>
-</sect2>
-<sect2 id="Output_Method_Functions">
-<title>Output Method Functions</title>
-<!-- .XS -->
-<!-- (SN Output Method Functions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To open an output method, use
-<function>XOpenOM</function>.
-<indexterm significance="preferred"><primary>XOpenOM</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XOM <function>XOpenOM</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XrmDatabase<parameter> db</parameter></paramdef>
- <paramdef>char<parameter> *res_name</parameter></paramdef>
- <paramdef>char<parameter> *res_class</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>db</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a pointer to the resource database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>res_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the full resource name of the application.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>res_class</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the full class name of the application.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XOpenOM</function>
-function opens an output method
-matching the current locale and modifiers specification.
-The current locale and modifiers are bound to the output method
-when
-<function>XOpenOM</function>
-is called.
-The locale associated with an output method cannot be changed.
-</para>
-<para>
-<!-- .LP -->
-The specific output method to which this call will be routed
-is identified on the basis of the current locale and modifiers.
-<function>XOpenOM</function>
-will identify a default output method corresponding to the
-current locale.
-That default can be modified using
-<function>XSetLocaleModifiers</function>
-to set the output method modifier.
-</para>
-<para>
-<!-- .LP -->
-The db argument is the resource database to be used by the output method
-for looking up resources that are private to the output method.
-It is not intended that this database be used to look
-up values that can be set as OC values in an output context.
-If db is NULL,
-no database is passed to the output method.
-</para>
-<para>
-<!-- .LP -->
-The res_name and res_class arguments specify the resource name
-and class of the application.
-They are intended to be used as prefixes by the output method
-when looking up resources that are common to all output contexts
-that may be created for this output method.
-The characters used for resource names and classes must be in the
-X Portable Character Set.
-The resources looked up are not fully specified
-if res_name or res_class is NULL.
-</para>
-<para>
-<!-- .LP -->
-The res_name and res_class arguments are not assumed to exist beyond
-the call to
-<function>XOpenOM</function>.
-The specified resource database is assumed to exist for the lifetime
-of the output method.
-</para>
-<para>
-<!-- .LP -->
-<function>XOpenOM</function>
-returns NULL if no output method could be opened.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To close an output method, use
-<function>XCloseOM</function>.
-<indexterm significance="preferred"><primary>XCloseOM</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XCloseOM</function></funcdef>
- <paramdef>XOM<parameter> om</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>om</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the output method.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCloseOM</function>
-function closes the specified output method.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set output method attributes, use
-<function>XSetOMValues</function>.
-<indexterm significance="preferred"><primary>XSetOMValues</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XSetOMValues</function></funcdef>
- <paramdef>XOM<parameter> om</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>om</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the output method.
-<!-- .ds Al \ to set <acronym>XOM</acronym> values -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- ...
- </term>
- <listitem>
- <para>
-Specifies the variable-length argument list(Al.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetOMValues</function>
-function presents a variable argument list programming interface
-for setting properties or features of the specified output method.
-This function returns NULL if it succeeds;
-otherwise,
-it returns the name of the first argument that could not be obtained.
-</para>
-<para>
-<!-- .LP -->
-No standard arguments are currently defined by Xlib.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To query an output method, use
-<function>XGetOMValues</function>.
-<indexterm significance="preferred"><primary>XGetOMValues</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XGetOMValues</function></funcdef>
- <paramdef>XOM<parameter> om</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>om</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the output method.
-<!-- .ds Al \ to get XOM values -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- ...
- </term>
- <listitem>
- <para>
-Specifies the variable-length argument list(Al.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetOMValues</function>
-function presents a variable argument list programming interface
-for querying properties or features of the specified output method.
-This function returns NULL if it succeeds;
-otherwise,
-it returns the name of the first argument that could not be obtained.
-</para>
-<para>
-<!-- .LP -->
-To obtain the display associated with an output method, use
-<function>XDisplayOfOM</function>.
-<indexterm significance="preferred"><primary>XDisplayOfOM</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Display *<function>XDisplayOfOM</function></funcdef>
- <paramdef>XOM<parameter> om</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>om</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the output method.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDisplayOfOM</function>
-function returns the display associated with the specified output method.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To get the locale associated with an output method, use
-<function>XLocaleOfOM</function>.
-<indexterm significance="preferred"><primary>XLocaleOfOM</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XLocaleOfOM</function></funcdef>
- <paramdef>XOM<parameter> om</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>om</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the output method.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XLocaleOfOM</function>
-returns the locale associated with the specified output method.
-</para>
-</sect2>
-<sect2 id="X_Output_Method_Values">
-<title>X Output Method Values</title>
-<!-- .XS -->
-<!-- (SN X Output Method Values -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The following table describes how <acronym>XOM</acronym> values are interpreted by an
-output method.
-The first column lists the <acronym>XOM</acronym> values. The second column indicates
-how each of the <acronym>XOM</acronym> values are treated by a particular output style.
-</para>
-<para>
-<!-- .LP -->
-</para>
-<para>
-<!-- .LP -->
-The following key applies to this table.
-</para>
-
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <thead>
- <row>
- <entry>Key</entry>
- <entry>Explanation</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry>G</entry>
- <entry>This value may be read using <function>XGetOMValues</function>.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <thead>
- <row>
- <entry><acronym>XOM</acronym> Value</entry>
- <entry>Key</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry><symbol>XNRequiredCharSet</symbol></entry>
- <entry>G</entry>
- </row>
- <row>
- <entry><symbol>XNQueryOrientation</symbol></entry>
- <entry>G</entry>
- </row>
- <row>
- <entry><symbol>XNDirectionalDependentDrawing</symbol></entry>
- <entry>G</entry>
- </row>
- <row>
- <entry><symbol>XNContextualDrawing</symbol></entry>
- <entry>G</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-</para>
-<sect3 id="Required_Char_Set">
-<title>Required Char Set</title>
-<!-- .XS -->
-<!-- (SN Required Char Set -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNRequiredCharSet</symbol>
-argument returns the list of charsets that are required for loading the fonts
-needed for the locale.
-The value of the argument is a pointer to a structure of type
-<structname>XOMCharSetList</structname>.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XOMCharSetList</structname>
-structure is defined as follows:
-<indexterm significance="preferred"><primary>XOMCharSetList</primary></indexterm>
-<!-- .sM -->
-</para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- int charset_count;
- char **charset_list;
-} XOMCharSetList;
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The charset_list member is a list of one or more null-terminated
-charset names, and the charset_count member is the number of
-charset names.
-</para>
-<para>
-<!-- .LP -->
-The required charset list is owned by Xlib and should not be modified or
-freed by the client.
-It will be freed by a call to
-<function>XCloseOM</function>
-with the associated
-<type>XOM</type>.
-Until freed, its contents will not be modified by Xlib.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-<sect3 id="Query_Orientation">
-<title>Query Orientation</title>
-<!-- .XS -->
-<!-- (SN Query Orientation -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNQueryOrientation</symbol>
-argument returns the global orientation of text when drawn.
-Other than
-<constant>XOMOrientation_LTR_TTB</constant>,
-the set of orientations supported is locale-dependent.
-The value of the argument is a pointer to a structure of type
-<structname>XOMOrientation</structname>.
-Clients are responsible for freeing the
-<structname>XOMOrientation</structname>
-structure by using
-<function>XFree</function>;
-this also frees the contents of the structure.
-</para>
-
-<!-- .LP -->
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- int num_orientation;
- XOrientation *orientation; /* Input Text description */
-} XOMOrientation;
-
-typedef enum {
- XOMOrientation_LTR_TTB,
- XOMOrientation_RTL_TTB,
- XOMOrientation_TTB_LTR,
- XOMOrientation_TTB_RTL,
- XOMOrientation_Context
-} XOrientation;
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The possible value for XOrientation may be:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-<constant>XOMOrientation_LTR_TTB</constant>
-left-to-right, top-to-bottom global orientation
- </para>
- </listitem>
- <listitem>
- <para>
-<constant>XOMOrientation_RTL_TTB</constant>
-right-to-left, top-to-bottom global orientation
- </para>
- </listitem>
- <listitem>
- <para>
-<constant>XOMOrientation_TTB_LTR</constant>
-top-to-bottom, left-to-right global orientation
- </para>
- </listitem>
- <listitem>
- <para>
-<constant>XOMOrientation_TTB_RTL</constant>
-top-to-bottom, right-to-left global orientation
- </para>
- </listitem>
- <listitem>
- <para>
-<constant>XOMOrientation_Context</constant>
-contextual global orientation
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-<sect3 id="Directional_Dependent_Drawing">
-<title>Directional Dependent Drawing</title>
-<!-- .XS -->
-<!-- (SN Directional Dependent Drawing -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNDirectionalDependentDrawing</symbol>
-argument indicates whether the text rendering functions
-implement implicit handling of directional text. If this value
-is
-<symbol>True</symbol>,
-the output method has knowledge of directional
-dependencies and reorders text as necessary when
-rendering text. If this value is
-<symbol>False</symbol>,
-the output method does not implement any directional text
-handling, and all character directions are assumed to be left-to-right.
-</para>
-<para>
-<!-- .LP -->
-Regardless of the rendering order of characters,
-the origins of all characters are on the primary draw direction side
-of the drawing origin.
-</para>
-<para>
-<!-- .LP -->
-This OM value presents functionality identical to the
-<function>XDirectionalDependentDrawing</function>
-function.
-</para>
-</sect3>
-<sect3 id="Context_Dependent_Drawing">
-<title>Context Dependent Drawing</title>
-<!-- .XS -->
-<!-- (SN Context Dependent Drawing -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNContextualDrawing</symbol>
-argument indicates whether the text rendering functions
-implement implicit context-dependent drawing. If this value is
-<symbol>True</symbol>,
-the output method has knowledge of context dependencies and
-performs character shape editing, combining glyphs to present
-a single character as necessary. The actual shape editing is
-dependent on the locale implementation and the font set used.
-</para>
-<para>
-<!-- .LP -->
-This OM value presents functionality identical to the
-<function>XContextualDrawing</function>
-function.
-</para>
-</sect3>
-</sect2>
-<sect2 id="Output_Context_Functions">
-<title>Output Context Functions</title>
-<!-- .XS -->
-<!-- (SN Output Context Functions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-An output context is an abstraction that contains both the data
-required by an output method and the information required
-to display that data.
-There can be multiple output contexts for one output method.
-The programming interfaces for creating, reading, or modifying
-an output context use a variable argument list.
-The name elements of the argument lists are referred to as <acronym>XOC</acronym> values.
-It is intended that output methods be controlled by these <acronym>XOC</acronym> values.
-As new <acronym>XOC</acronym> values are created,
-they should be registered with the X Consortium.
-An
-<type>XOC</type>
-can be used anywhere an
-<type>XFontSet</type>
-can be used, and vice versa;
-<type>XFontSet</type>
-is retained for compatibility with previous releases.
-The concepts of output methods and output contexts include broader,
-more generalized abstraction than font set,
-supporting complex and more intelligent text display, and dealing not only
-with multiple fonts but also with context dependencies.
-However,
-<type>XFontSet</type>
-is widely used in several interfaces, so
-<type>XOC</type>
-is defined as an upward compatible type of
-<type>XFontSet</type>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create an output context, use
-<function>XCreateOC</function>.
-<indexterm significance="preferred"><primary>XCreateOC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XOC <function>XCreateOC</function></funcdef>
- <paramdef>XOM<parameter> om</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>om</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the output method.
-<!-- .ds Al \ to set <acronym>XOC</acronym> values -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- ...
- </term>
- <listitem>
- <para>
-Specifies the variable-length argument list(Al.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreateOC</function>
-function creates an output context within the specified output method.
-</para>
-<para>
-<!-- .LP -->
-The base font names argument is mandatory at creation time, and
-the output context will not be created unless it is provided.
-All other output context values can be set later.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreateOC</function>
-returns NULL if no output context could be created.
-NULL can be returned for any of the following reasons:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-A required argument was not set.
- </para>
- </listitem>
- <listitem>
- <para>
-A read-only argument was set.
- </para>
- </listitem>
- <listitem>
- <para>
-An argument name is not recognized.
- </para>
- </listitem>
- <listitem>
- <para>
-The output method encountered an output method implementation-dependent error.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-<function>XCreateOC</function>
-can generate a
-<errorname>BadAtom</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To destroy an output context, use
-<function>XDestroyOC</function>.
-<indexterm significance="preferred"><primary>XDestroyOC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XDestroyOC</function></funcdef>
- <paramdef>XOC<parameter> oc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>oc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the output context.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDestroyOC</function>
-function destroys the specified output context.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To get the output method associated with an output context, use
-<function>XOMOfOC</function>.
-<indexterm significance="preferred"><primary>XOMOfOC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XOM <function>XOMOfOC</function></funcdef>
- <paramdef>XOC<parameter> oc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>oc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the output context.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XOMOfOC</function>
-function returns the output method associated with the
-specified output context.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-Xlib provides two functions for setting and reading output context values,
-respectively,
-<function>XSetOCValues</function>
-and
-<function>XGetOCValues</function>.
-Both functions have a variable-length argument list.
-In that argument list, any <acronym>XOC</acronym> value's name must be denoted
-with a character string using the X Portable Character Set.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set <acronym>XOC</acronym> values, use
-<function>XSetOCValues</function>.
-<indexterm significance="preferred"><primary>XSetOCValues</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XSetOCValues</function></funcdef>
- <paramdef>XOC<parameter> oc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>oc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the output context.
-<!-- .ds Al \ to set <acronym>XOC</acronym> values -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- ...
- </term>
- <listitem>
- <para>
-Specifies the variable-length argument list(Al.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetOCValues</function>
-function returns NULL if no error occurred;
-otherwise,
-it returns the name of the first argument that could not be set.
-An argument might not be set for any of the following reasons:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The argument is read-only.
- </para>
- </listitem>
- <listitem>
- <para>
-The argument name is not recognized.
- </para>
- </listitem>
- <listitem>
- <para>
-An implementation-dependent error occurs.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Each value to be set must be an appropriate datum,
-matching the data type imposed by the semantics of the argument.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetOCValues</function>
-can generate a
-<errorname>BadAtom</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain <acronym>XOC</acronym> values, use
-<function>XGetOCValues</function>.
-<indexterm significance="preferred"><primary>XGetOCValues</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XGetOCValues</function></funcdef>
- <paramdef>XOC<parameter> oc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>oc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the output context.
-<!-- .ds Al \ to get XOC values -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- ...
- </term>
- <listitem>
- <para>
-Specifies the variable-length argument list(Al.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetOCValues</function>
-function returns NULL if no error occurred; otherwise,
-it returns the name of the first argument that could not be obtained.
-An argument might not be obtained for any of the following reasons:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The argument name is not recognized.
- </para>
- </listitem>
- <listitem>
- <para>
-An implementation-dependent error occurs.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Each argument value
-following a name must point to a location where the value is to be stored.
-</para>
-</sect2>
-
-<sect2 id="Output_Context_Values">
-<title>Output Context Values</title>
-<!-- .XS -->
-<!-- (SN Output Context Values -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The following table describes how <acronym>XOC</acronym> values are interpreted
-by an output method.
-The first column lists the <acronym>XOC</acronym> values.
-The second column indicates the alternative interfaces that function
-identically and are provided for compatibility with previous releases.
-The third column indicates how each of the <acronym>XOC</acronym> values is treated.
-</para>
-<!-- .LP -->
-<para>
-The following keys apply to this table.
-</para>
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <thead>
- <row>
- <entry>Key</entry>
- <entry>Explanation</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry>C</entry>
- <entry>This value must be set with <function>XCreateOC</function>.</entry>
- </row>
- <row>
- <entry>D</entry>
- <entry>This value may be set using <function>XCreateOC</function>.
- If it is not set,a default is provided.</entry>
- </row>
- <row>
- <entry>G</entry>
- <entry>This value may be read using <function>XGetOCValues</function>.</entry>
- </row>
- <row>
- <entry>S</entry>
- <entry>This value must be set using <function>XSetOCValues</function>.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<!-- .LP -->
-<informaltable>
- <tgroup cols='3' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <thead>
- <row>
- <entry><acronym>XOC</acronym> Value</entry>
- <entry>Alternative Interface</entry>
- <entry>Key</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry>BaseFontName</entry>
- <entry><function>XCreateFontSet</function></entry>
- <entry>C-G</entry>
- </row>
- <row>
- <entry>MissingCharSet</entry>
- <entry><function>XCreateFontSet</function></entry>
- <entry>G</entry>
- </row>
- <row>
- <entry>DefaultString</entry>
- <entry><function>XCreateFontSet</function></entry>
- <entry>G</entry>
- </row>
- <row>
- <entry>Orientation</entry>
- <entry>-</entry>
- <entry>D-S-G</entry>
- </row>
- <row>
- <entry>ResourceName</entry>
- <entry>-</entry>
- <entry>S-G</entry>
- </row>
- <row>
- <entry>ResourceClass</entry>
- <entry>-</entry>
- <entry>S-G</entry>
- </row>
- <row>
- <entry>FontInfo</entry>
- <entry><function>XFontsOfFontSet</function></entry>
- <entry>G</entry>
- </row>
- <row>
- <entry>OMAutomatic</entry>
- <entry>-</entry>
- <entry>G</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-</para>
-<sect3 id="Base_Font_Name">
-<title>Base Font Name</title>
-<!-- .XS -->
-<!-- (SN Base Font Name -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNBaseFontName</symbol>
-argument is a list of base font names that Xlib uses
-to load the fonts needed for the locale.
-The base font names are a comma-separated list. The string is null-terminated
-and is assumed to be in the Host Portable Character Encoding;
-otherwise, the result is implementation-dependent.
-White space immediately on either side of a separating comma is ignored.
-</para>
-<para>
-<!-- .LP -->
-Use of <acronym>XLFD</acronym> font names permits Xlib to obtain the fonts needed for a
-variety of locales from a single locale-independent base font name.
-The single base font name should name a family of fonts whose members
-are encoded in the various charsets needed by the locales of interest.
-</para>
-<para>
-<!-- .LP -->
-An <acronym>XLFD</acronym> base font name can explicitly name a charset needed for the locale.
-This allows the user to specify an exact font for use with a charset required
-by a locale, fully controlling the font selection.
-</para>
-<para>
-<!-- .LP -->
-If a base font name is not an <acronym>XLFD</acronym> name,
-Xlib will attempt to obtain an <acronym>XLFD</acronym> name from the font properties
-for the font.
-If Xlib is successful, the
-<function>XGetOCValues</function>
-function will return this <acronym>XLFD</acronym> name instead of the client-supplied name.
-</para>
-<para>
-<!-- .LP -->
-This argument must be set at creation time
-and cannot be changed.
-If no fonts exist for any of the required charsets,
-or if the locale definition in Xlib requires that a font exist
-for a particular charset and a font is not found for that charset,
-<function>XCreateOC</function>
-returns NULL.
-</para>
-<para>
-<!-- .LP -->
-When querying for the
-<symbol>XNBaseFontName</symbol>
-<acronym>XOC</acronym> value,
-<function>XGetOCValues</function>
-returns a null-terminated string identifying the base font names that
-Xlib used to load the fonts needed for the locale.
-This string is owned by Xlib and should not be modified or freed by
-the client.
-The string will be freed by a call to
-<function>XDestroyOC</function>
-with the associated
-<type>XOC</type>.
-Until freed, the string contents will not be modified by Xlib.
-</para>
-</sect3>
-<sect3 id="Missing_CharSet">
-<title>Missing CharSet</title>
-<!-- .XS -->
-<!-- (SN Missing CharSet -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNMissingCharSet</symbol>
-argument returns the list of required charsets that are missing from the
-font set.
-The value of the argument is a pointer to a structure of type
-<structname>XOMCharSetList</structname>.
-</para>
-<para>
-<!-- .LP -->
-If fonts exist for all of the charsets required by the current locale,
-charset_list is set to NULL and charset_count is set to zero.
-If no fonts exist for one or more of the required charsets,
-charset_list is set to a list of one or more null-terminated charset names
-for which no fonts exist, and charset_count is set to the number of
-missing charsets.
-The charsets are from the list of the required charsets for
-the encoding of the locale and do not include any charsets to which Xlib
-may be able to remap a required charset.
-</para>
-<para>
-<!-- .LP -->
-The missing charset list is owned by Xlib and should not be modified or
-freed by the client.
-It will be freed by a call to
-<function>XDestroyOC</function>
-with the associated
-<type>XOC</type>.
-Until freed, its contents will not be modified by Xlib.
-</para>
-</sect3>
-<sect3 id="Default_String">
-<title>Default String</title>
-<!-- .XS -->
-<!-- (SN Default String -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-When a drawing or measuring function is called with an
-<type>XOC</type>
-that has missing charsets, some characters in the locale will not be
-drawable.
-The
-<symbol>XNDefaultString</symbol>
-argument returns a pointer to a string that represents the glyphs
-that are drawn with this
-<type>XOC</type>
-when the charsets of the available fonts do not include all glyphs
-required to draw a character.
-The string does not necessarily consist of valid characters
-in the current locale and is not necessarily drawn with
-the fonts loaded for the font set,
-but the client can draw or measure the default glyphs
-by including this string in a string being drawn or measured with the
-<type>XOC</type>.
-</para>
-<para>
-<!-- .LP -->
-If the
-<symbol>XNDefaultString</symbol>
-argument returned the empty string (""),
-no glyphs are drawn and the escapement is zero.
-The returned string is null-terminated.
-It is owned by Xlib and should not be modified or freed by the client.
-It will be freed by a call to
-<function>XDestroyOC</function>
-with the associated
-<type>XOC</type>.
-Until freed, its contents will not be modified by Xlib.
-</para>
-</sect3>
-<sect3 id="Orientation">
-<title>Orientation</title>
-<!-- .XS -->
-<!-- (SN Orientation -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNOrientation</symbol>
-argument specifies the current orientation of text when drawn. The value of
-this argument is one of the values returned by the
-<function>XGetOMValues</function>
-function with the
-<symbol>XNQueryOrientation</symbol>
-argument specified in the
-<type>XOrientation</type>
-list.
-The value of the argument is of type
-<type>XOrientation</type>.
-When
-<symbol>XNOrientation</symbol>
-is queried, the value specifies the current orientation.
-When
-<symbol>XNOrientation</symbol>
-is set, a value is used to set the current orientation.
-</para>
-<para>
-<!-- .LP -->
-When
-<constant>XOMOrientation_Context</constant>
-is set, the text orientation of the
-text is determined according to an implementation-defined method
-(for example, ISO 6429 control sequences), and the initial text orientation for
-locale-dependent Xlib functions is assumed to
-be
-<constant>XOMOrientation_LTR_TTB</constant>.
-</para>
-<para>
-<!-- .LP -->
-The
-<symbol>XNOrientation</symbol>
-value does not change the prime drawing direction
-for Xlib drawing functions.
-</para>
-</sect3>
-<sect3 id="Resource_Name_and_Class">
-<title>Resource Name and Class</title>
-<!-- .XS -->
-<!-- (SN Resource Name and Class -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNResourceName</symbol>
-and
-<symbol>XNResourceClass</symbol>
-arguments are strings that specify the full name and class
-used by the client to obtain resources for the display of the output context.
-These values should be used as prefixes for name and class
-when looking up resources that may vary according to the output context.
-If these values are not set,
-the resources will not be fully specified.
-</para>
-<para>
-<!-- .LP -->
-It is not intended that values that can be set as <acronym>XOM</acronym> values be
-set as resources.
-</para>
-<para>
-<!-- .LP -->
-When querying for the
-<symbol>XNResourceName</symbol>
-or
-<symbol>XNResourceClass</symbol>
-<acronym>XOC</acronym> value,
-<function>XGetOCValues</function>
-returns a null-terminated string.
-This string is owned by Xlib and should not be modified or freed by
-the client.
-The string will be freed by a call to
-<function>XDestroyOC</function>
-with the associated
-<type>XOC</type>
-or when the associated value is changed via
-<function>XSetOCValues</function>.
-Until freed, the string contents will not be modified by Xlib.
-</para>
-</sect3>
-<sect3 id="Font_Info">
-<title>Font Info</title>
-<!-- .XS -->
-<!-- (SN Font Info -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNFontInfo</symbol>
-argument specifies a list of one or more
-<structname>XFontStruct</structname>
-structures
-and font names for the fonts used for drawing by the given output context.
-The value of the argument is a pointer to a structure of type
-<structname>XOMFontInfo</structname>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- int num_font;
- XFontStruct **font_struct_list;
- char **font_name_list;
-} XOMFontInfo;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-A list of pointers to the
-<structname>XFontStruct</structname>
-structures is returned to font_struct_list.
-A list of pointers to null-terminated, fully-specified font name strings
-in the locale of the output context is returned to font_name_list.
-The font_name_list order corresponds to the font_struct_list order.
-The number of
-<structname>XFontStruct</structname>
-structures and font names is returned to num_font.
-</para>
-<para>
-<!-- .LP -->
-Because it is not guaranteed that a given character will be imaged using a
-single font glyph,
-there is no provision for mapping a character or default string
-to the font properties, font ID, or direction hint for the font
-for the character.
-The client may access the
-<structname>XFontStruct</structname>
-list to obtain these values for all the fonts currently in use.
-</para>
-<para>
-<!-- .LP -->
-Xlib does not guarantee that fonts are loaded from the server
-at the creation of an
-<type>XOC</type>.
-Xlib may choose to cache font data, loading it only as needed to draw text
-or compute text dimensions.
-Therefore, existence of the per_char metrics in the
-<structname>XFontStruct</structname>
-structures in the
-<structname>XFontStructSet</structname>
-is undefined.
-Also, note that all properties in the
-<structname>XFontStruct</structname>
-structures are in the STRING encoding.
-</para>
-<para>
-<!-- .LP -->
-The client must not free the
-<structname>XOMFontInfo</structname>
-struct itself; it will be freed when the
-<type>XOC</type>
-is closed.
-</para>
-</sect3>
-<sect3 id="OM_Automatic">
-<title>OM Automatic</title>
-<!-- .XS -->
-<!-- (SN OM Automatic -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNOMAutomatic</symbol>
-argument returns whether the associated output context was created by
-<function>XCreateFontSet</function>
-or not. Because the
-<function>XFreeFontSet</function>
-function not only destroys the output context but also closes the implicit
-output method associated with it,
-<function>XFreeFontSet</function>
-should be used with any output context created by
-<function>XCreateFontSet</function>.
-However, it is possible that a client does not know how the output context
-was created.
-Before a client destroys the output context,
-it can query whether
-<symbol>XNOMAutomatic</symbol>
-is set to determine whether
-<function>XFreeFontSet</function>
-or
-<function>XDestroyOC</function>
-should be used to destroy the output context.
-</para>
-</sect3>
-</sect2>
-<sect2 id="Creating_and_Freeing_a_Font_Set">
-<title>Creating and Freeing a Font Set</title>
-<!-- .XS -->
-<!-- (SN Creating and Freeing a Font Set -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib international text drawing is done using a set of one or more fonts,
-as needed for the locale of the text.
-Fonts are loaded according to a list of base font names
-supplied by the client and the charsets required by the locale.
-The
-<type>XFontSet</type>
-is an opaque type representing the state of a particular output thread
-and is equivalent to the type
-<type>XOC</type>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-The
-<function>XCreateFontSet</function>
-function is a convenience function for creating an output context using
-only default values. The returned
-<type>XFontSet</type>
-has an implicitly created
-<type>XOM</type>.
-This
-<type>XOM</type>
-has an OM value
-<symbol>XNOMAutomatic</symbol>
-automatically set to
-<symbol>True</symbol>
-so that the output context self indicates whether it was created by
-<function>XCreateOC</function>
-or
-<function>XCreateFontSet</function>.
-<indexterm significance="preferred"><primary>XCreateFontSet</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XFontSet <function>XCreateFontSet</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *base_font_name_list</parameter></paramdef>
- <paramdef>char<parameter> ***missing_charset_list_return</parameter></paramdef>
- <paramdef>int<parameter> *missing_charset_count_return</parameter></paramdef>
- <paramdef>char<parameter> **def_string_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>base_font_name_list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the base font names.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>missing_charset_list_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the missing charsets.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>missing_charset_count_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of missing charsets.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>def_string_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the string drawn for missing charsets.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreateFontSet</function>
-function creates a font set for the specified display.
-The font set is bound to the current locale when
-<function>XCreateFontSet</function>
-is called.
-The font set may be used in subsequent calls to obtain font
-and character information and to image text in the locale of the font set.
-</para>
-<para>
-<!-- .LP -->
-The base_font_name_list argument is a list of base font names
-that Xlib uses to load the fonts needed for the locale.
-The base font names are a comma-separated list.
-The string is null-terminated
-and is assumed to be in the Host Portable Character Encoding;
-otherwise, the result is implementation-dependent.
-White space immediately on either side of a separating comma is ignored.
-</para>
-<para>
-<!-- .LP -->
-Use of <acronym>XLFD</acronym> font names permits Xlib to obtain the fonts needed for a
-variety of locales from a single locale-independent base font name.
-The single base font name should name a family of fonts whose members
-are encoded in the various charsets needed by the locales of interest.
-</para>
-<para>
-<!-- .LP -->
-An <acronym>XLFD</acronym> base font name can explicitly name a charset needed for the locale.
-This allows the user to specify an exact font for use with a charset required
-by a locale, fully controlling the font selection.
-</para>
-<para>
-<!-- .LP -->
-If a base font name is not an <acronym>XLFD</acronym> name,
-Xlib will attempt to obtain an <acronym>XLFD</acronym> name from the font properties
-for the font.
-If this action is successful in obtaining an <acronym>XLFD</acronym> name, the
-<function>XBaseFontNameListOfFontSet</function>
-function will return this <acronym>XLFD</acronym> name instead of the client-supplied name.
-</para>
-<para>
-<!-- .LP -->
-Xlib uses the following algorithm to select the fonts
-that will be used to display text with the
-<type>XFontSet</type>.
-</para>
-<para>
-<!-- .LP -->
-For each font charset required by the locale,
-the base font name list is searched for the first appearance of one
-of the following cases that names a set of fonts that exist at the server:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The first <acronym>XLFD</acronym>-conforming base font name that specifies the required
-charset or a superset of the required charset in its
-<structfield>CharSetRegistry</structfield>
-and
-<structfield>CharSetEncoding</structfield>
-fields.
-The implementation may use a base font name whose specified charset
-is a superset of the required charset, for example,
-an ISO8859-1 font for an ASCII charset.
- </para>
- </listitem>
- <listitem>
- <para>
-The first set of one or more <acronym>XLFD</acronym>-conforming base font names
-that specify one or more charsets that can be remapped to support the
-required charset.
-The Xlib implementation may recognize various mappings
-from a required charset to one or more other charsets
-and use the fonts for those charsets.
-For example, JIS Roman is ASCII with tilde and backslash replaced
-by yen and overbar;
-Xlib may load an ISO8859-1 font to support this character set
-if a JIS Roman font is not available.
- </para>
- </listitem>
- <listitem>
- <para>
-The first <acronym>XLFD</acronym>-conforming font name or the first non-<acronym>XLFD</acronym> font name
-for which an <acronym>XLFD</acronym> font name can be obtained, combined with the
-required charset (replacing the
-<structfield>CharSetRegistry</structfield>
-and
-<structfield>CharSetEncoding</structfield>
-fields in the <acronym>XLFD</acronym> font name).
-As in case 1,
-the implementation may use a charset that is a superset
-of the required charset.
- </para>
- </listitem>
- <listitem>
- <para>
-The first font name that can be mapped in some implementation-dependent
-manner to one or more fonts that support imaging text in the charset.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-For example, assume that a locale required the charsets:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-ISO8859-1
-JISX0208.1983
-JISX0201.1976
-GB2312-1980.0
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The user could supply a base_font_name_list that explicitly specifies the
-charsets, ensuring that specific fonts are used if they exist.
-For example:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-"-JIS-Fixed-Medium-R-Normal--26-180-100-100-C-240-JISX0208.1983-0,\\
--JIS-Fixed-Medium-R-Normal--26-180-100-100-C-120-JISX0201.1976-0,\\
--GB-Fixed-Medium-R-Normal--26-180-100-100-C-240-GB2312-1980.0,\\
--Adobe-Courier-Bold-R-Normal--25-180-75-75-M-150-ISO8859-1"
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-Alternatively, the user could supply a base_font_name_list
-that omits the charsets,
-letting Xlib select font charsets required for the locale.
-For example:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-"-JIS-Fixed-Medium-R-Normal--26-180-100-100-C-240,\\
--JIS-Fixed-Medium-R-Normal--26-180-100-100-C-120,\\
--GB-Fixed-Medium-R-Normal--26-180-100-100-C-240,\\
--Adobe-Courier-Bold-R-Normal--25-180-100-100-M-150"
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-Alternatively, the user could simply supply a single base font name
-that allows Xlib to select from all available fonts
-that meet certain minimum <acronym>XLFD</acronym> property requirements.
-For example:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-"-*-*-*-R-Normal--*-180-100-100-*-*"
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-If
-<function>XCreateFontSet</function>
-is unable to create the font set,
-either because there is insufficient memory or because the current locale
-is not supported,
-<function>XCreateFontSet</function>
-returns NULL, missing_charset_list_return is set to NULL,
-and missing_charset_count_return
-is set to zero.
-If fonts exist for all of the charsets required by the current locale,
-<function>XCreateFontSet</function>
-returns a valid
-<type>XFontSet</type>,
-missing_charset_list_return is set to NULL,
-and missing_charset_count_return is set to zero.
-</para>
-<para>
-<!-- .LP -->
-If no font exists for one or more of the required charsets,
-<function>XCreateFontSet</function>
-sets missing_charset_list_return to a
-list of one or more null-terminated charset names for which no font exists
-and sets missing_charset_count_return to the number of missing fonts.
-The charsets are from the list of the required charsets for
-the encoding of the locale and do not include any charsets to which Xlib
-may be able to remap a required charset.
-</para>
-<para>
-<!-- .LP -->
-If no font exists for any of the required charsets
-or if the locale definition in Xlib requires that a font exist
-for a particular charset and a font is not found for that charset,
-<function>XCreateFontSet</function>
-returns NULL.
-Otherwise,
-<function>XCreateFontSet</function>
-returns a valid
-<type>XFontSet</type>
-to font_set.
-</para>
-<para>
-<!-- .LP -->
-When an Xmb/wc drawing or measuring function is called with an
-<type>XFontSet</type>
-that has missing charsets, some characters in the locale will not be
-drawable.
-If def_string_return is non-NULL,
-<function>XCreateFontSet</function>
-returns a pointer to a string that represents the glyphs
-that are drawn with this
-<type>XFontSet</type>
-when the charsets of the available fonts do not include all font glyphs
-required to draw a codepoint.
-The string does not necessarily consist of valid characters
-in the current locale and is not necessarily drawn with
-the fonts loaded for the font set,
-but the client can draw and measure the default glyphs
-by including this string in a string being drawn or measured with the
-<type>XFontSet</type>.
-</para>
-<para>
-<!-- .LP -->
-If the string returned to def_string_return is the empty string (""),
-no glyphs are drawn, and the escapement is zero.
-The returned string is null-terminated.
-It is owned by Xlib and should not be modified or freed by the client.
-It will be freed by a call to
-<function>XFreeFontSet</function>
-with the associated
-<type>XFontSet</type>.
-Until freed, its contents will not be modified by Xlib.
-</para>
-<para>
-<!-- .LP -->
-The client is responsible for constructing an error message from the
-missing charset and default string information and may choose to continue
-operation in the case that some fonts did not exist.
-</para>
-<para>
-<!-- .LP -->
-The returned
-<type>XFontSet</type>
-and missing charset list should be freed with
-<function>XFreeFontSet</function>
-and
-<function>XFreeStringList</function>,
-respectively.
-The client-supplied base_font_name_list may be freed
-by the client after calling
-<function>XCreateFontSet</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain a list of
-<structname>XFontStruct</structname>
-structures and full font names given an
-<type>XFontSet</type>,
-use
-<function>XFontsOfFontSet</function>.
-<indexterm significance="preferred"><primary>XFontsOfFontSet</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XFontsOfFontSet</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
- <paramdef>XFontStruct<parameter> ***font_struct_list_return</parameter></paramdef>
- <paramdef>char<parameter> ***font_name_list_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_struct_list_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the list of font structs.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_name_list_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the list of font names.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFontsOfFontSet</function>
-function returns a list of one or more
-<structname>XFontStruct</structname>s
-and font names for the fonts used by the Xmb and Xwc layers
-for the given font set.
-A list of pointers to the
-<structname>XFontStruct</structname>
-structures is returned to font_struct_list_return.
-A list of pointers to null-terminated, fully specified font name strings
-in the locale of the font set is returned to font_name_list_return.
-The font_name_list order corresponds to the font_struct_list order.
-The number of
-<structname>XFontStruct</structname>
-structures and font names is returned as the value of the function.
-</para>
-<para>
-<!-- .LP -->
-Because it is not guaranteed that a given character will be imaged using a
-single font glyph,
-there is no provision for mapping a character or default string
-to the font properties, font ID, or direction hint for the font
-for the character.
-The client may access the
-<structname>XFontStruct</structname>
-list to obtain these values for all the fonts currently in use.
-</para>
-<para>
-<!-- .LP -->
-Xlib does not guarantee that fonts are loaded from the server
-at the creation of an
-<type>XFontSet</type>.
-Xlib may choose to cache font data, loading it only as needed to draw text
-or compute text dimensions.
-Therefore, existence of the per_char metrics in the
-<structname>XFontStruct</structname>
-structures in the
-<structname>XFontStructSet</structname>
-is undefined.
-Also, note that all properties in the
-<structname>XFontStruct</structname>
-structures are in the STRING encoding.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XFontStruct</structname>
-and font name lists are owned by Xlib
-and should not be modified or freed by the client.
-They will be freed by a call to
-<function>XFreeFontSet</function>
-with the associated
-<type>XFontSet</type>.
-Until freed, their contents will not be modified by Xlib.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the base font name list and the selected font name list given an
-<type>XFontSet</type>,
-use
-<function>XBaseFontNameListOfFontSet</function>.
-<indexterm significance="preferred"><primary>XBaseFontNameListOfFontSet</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XBaseFontNameListOfFontSet</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XBaseFontNameListOfFontSet</function>
-function returns the original base font name list supplied
-by the client when the
-<type>XFontSet</type>
-was created.
-A null-terminated string containing a list of
-comma-separated font names is returned
-as the value of the function.
-White space may appear immediately on either side of separating commas.
-</para>
-<para>
-<!-- .LP -->
-If
-<function>XCreateFontSet</function>
-obtained an <acronym>XLFD</acronym> name from the font properties for the font specified
-by a non-<acronym>XLFD</acronym> base name, the
-<function>XBaseFontNameListOfFontSet</function>
-function will return the <acronym>XLFD</acronym> name instead of the non-<acronym>XLFD</acronym> base name.
-</para>
-<para>
-<!-- .LP -->
-The base font name list is owned by Xlib and should not be modified or
-freed by the client.
-It will be freed by a call to
-<function>XFreeFontSet</function>
-with the associated
-<type>XFontSet</type>.
-Until freed, its contents will not be modified by Xlib.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the locale name given an
-<type>XFontSet</type>,
-use
-<function>XLocaleOfFontSet</function>.
-<indexterm significance="preferred"><primary>XLocaleOfFontSet</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XLocaleOfFontSet</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XLocaleOfFontSet</function>
-function
-returns the name of the locale bound to the specified
-<type>XFontSet</type>,
-as a null-terminated string.
-</para>
-<para>
-<!-- .LP -->
-The returned locale name string is owned by Xlib
-and should not be modified or freed by the client.
-It may be freed by a call to
-<function>XFreeFontSet</function>
-with the associated
-<type>XFontSet</type>.
-Until freed, it will not be modified by Xlib.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-The
-<function>XFreeFontSet</function>
-function is a convenience function for freeing an output context.
-<function>XFreeFontSet</function>
-also frees its associated
-<type>XOM</type>
-if the output context was created by
-<function>XCreateFontSet</function>.
-<indexterm significance="preferred"><primary>XFreeFontSet</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XFreeFontSet</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreeFontSet</function>
-function frees the specified font set.
-The associated base font name list, font name list,
-<structname>XFontStruct</structname>
-list, and
-<structname>XFontSetExtents</structname>,
-if any, are freed.
-</para>
-</sect2>
-<sect2 id="Obtaining_Font_Set_Metrics">
-<title>Obtaining Font Set Metrics</title>
-<!-- .XS -->
-<!-- (SN Obtaining Font Set Metrics -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Metrics for the internationalized text drawing functions
-are defined in terms of a primary draw direction,
-which is the default direction in which the character origin advances
-for each succeeding character in the string.
-The Xlib interface is currently defined to support only a left-to-right
-primary draw direction.
-The drawing origin is the position passed to the drawing function
-when the text is drawn.
-The baseline is a line drawn through the drawing origin parallel
-to the primary draw direction.
-Character ink is the pixels painted in the foreground color
-and does not include interline or intercharacter spacing
-or image text background pixels.
-</para>
-<para>
-<!-- .LP -->
-The drawing functions are allowed to implement implicit text
-directionality control, reversing the order in which characters are
-rendered along the primary draw direction in response to locale-specific
-lexical analysis of the string.
-</para>
-<para>
-<!-- .LP -->
-Regardless of the character rendering order,
-the origins of all characters are on the primary draw direction side
-of the drawing origin.
-The screen location of a particular character image may be determined with
-<function>XmbTextPerCharExtents</function>
-or
-<function>XwcTextPerCharExtents</function>.
-</para>
-<para>
-<!-- .LP -->
-The drawing functions are allowed to implement context-dependent
-rendering, where the glyphs drawn for a string are not simply a
-concatenation of the glyphs that represent each individual character.
-A string of two characters drawn with
-<function>XmbDrawString</function>
-may render differently than if the two characters
-were drawn with separate calls to
-<function>XmbDrawString</function>.
-If the client appends or inserts a character
-in a previously drawn string,
-the client may need to redraw some adjacent characters
-to obtain proper rendering.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To find out about direction-dependent rendering, use
-<function>XDirectionalDependentDrawing</function>.
-<indexterm significance="preferred"><primary>XDirectionalDependentDrawing</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XDirectionalDependentDrawing</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDirectionalDependentDrawing</function>
-function returns
-<symbol>True</symbol>
-if the drawing functions implement implicit text directionality;
-otherwise, it returns
-<symbol>False</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To find out about context-dependent rendering, use
-<function>XContextualDrawing</function>.
-<indexterm significance="preferred"><primary>XContextualDrawing</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XContextualDrawing</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XContextualDrawing</function>
-function returns
-<symbol>True</symbol>
-if text drawn with the font set might include context-dependent drawing;
-otherwise, it returns
-<symbol>False</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To find out about context-dependent or direction-dependent rendering, use
-<function>XContextDependentDrawing</function>.
-<indexterm significance="preferred"><primary>XContextDependentDrawing</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XContextDependentDrawing</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XContextDependentDrawing</function>
-function returns
-<symbol>True</symbol>
-if the drawing functions implement implicit text directionality or
-if text drawn with the font_set might include context-dependent drawing;
-otherwise, it returns
-<symbol>False</symbol>.
-</para>
-<para>
-<!-- .LP -->
-The drawing functions do not interpret newline, tab, or other control
-characters.
-The behavior when nonprinting characters other than space are drawn
-is implementation-dependent.
-It is the client's responsibility to interpret control characters
-in a text stream.
-</para>
-<para>
-<!-- .LP -->
-The maximum character extents for the fonts that are used by the text
-drawing layers can be accessed by the
-<structname>XFontSetExtents</structname>
-structure:
-<indexterm significance="preferred"><primary>XFontSetExtents</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-typedef struct {
- XRectangle max_ink_extent; /* over all drawable characters */
- XRectangle max_logical_extent; /* over all drawable characters */
-} XFontSetExtents;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XRectangle</structname>
-structures used to return font set metrics are the usual Xlib screen-oriented
-rectangles
-with x, y giving the upper left corner, and width and height always positive.
-</para>
-<para>
-<!-- .LP -->
-The max_ink_extent member gives the maximum extent, over all drawable characters, of
-the rectangles that bound the character glyph image drawn in the
-foreground color, relative to a constant origin.
-See
-<function>XmbTextExtents</function>
-and
-<function>XwcTextExtents</function>
-for detailed semantics.
-</para>
-<para>
-<!-- .LP -->
-The max_logical_extent member gives the maximum extent,
-over all drawable characters, of the rectangles
-that specify minimum spacing to other graphical features,
-relative to a constant origin.
-Other graphical features drawn by the client, for example,
-a border surrounding the text, should not intersect this rectangle.
-The max_logical_extent member should be used to compute minimum
-interline spacing and the minimum area that must be allowed
-in a text field to draw a given number of arbitrary characters.
-</para>
-<para>
-<!-- .LP -->
-Due to context-dependent rendering,
-appending a given character to a string may change
-the string's extent by an amount other than that character's
-individual extent.
-</para>
-<para>
-<!-- .LP -->
-The rectangles for a given character in a string can be obtained from
-<function>XmbTextPerCharExtents</function>
-or
-<function>XwcTextPerCharExtents</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the maximum extents structure given an
-<type>XFontSet</type>,
-use
-<function>XExtentsOfFontSet</function>.
-<indexterm significance="preferred"><primary>XExtentsOfFontSet</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XFontSetExtents *<function>XExtentsOfFontSet</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XExtentsOfFontSet</function>
-function returns an
-<structname>XFontSetExtents</structname>
-structure for the fonts used by the Xmb and Xwc layers
-for the given font set.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XFontSetExtents</structname>
-structure is owned by Xlib and should not be modified
-or freed by the client.
-It will be freed by a call to
-<function>XFreeFontSet</function>
-with the associated
-<type>XFontSet</type>.
-Until freed, its contents will not be modified by Xlib.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the escapement in pixels of the specified text as a value,
-use
-<function>XmbTextEscapement</function>
-or
-<function>XwcTextEscapement</function>.
-<indexterm significance="preferred"><primary>XmbTextEscapement</primary></indexterm>
-<indexterm significance="preferred"><primary>XwcTextEscapement</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XmbTextEscapement</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> num_bytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XwcTextEscapement</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
- <paramdef>wchar_t<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> num_wchars</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_bytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes in the string argument.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_wchars</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the string argument.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XmbTextEscapement</function>
-and
-<function>XwcTextEscapement</function>
-functions return the escapement in pixels of the specified string as a value,
-using the fonts loaded for the specified font set.
-The escapement is the distance in pixels in the primary draw
-direction from the drawing origin to the origin of the next character to
-be drawn, assuming that the rendering of the next character is not
-dependent on the supplied string.
-</para>
-<para>
-<!-- .LP -->
-Regardless of the character rendering order,
-the escapement is always positive.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the overall_ink_return and overall_logical_return arguments,
-the overall bounding box of the string's image, and a logical bounding box,
-use
-<function>XmbTextExtents</function>
- or
-<function>XwcTextExtents</function>.
-<indexterm significance="preferred"><primary>XmbTextExtents</primary></indexterm>
-<indexterm significance="preferred"><primary>XwcTextExtents</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XmbTextExtents</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> num_bytes</parameter></paramdef>
- <paramdef>XRectangle<parameter> *overall_ink_return</parameter></paramdef>
- <paramdef>XRectangle<parameter> *overall_logical_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XwcTextExtents</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
- <paramdef>wchar_t<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> num_wchars</parameter></paramdef>
- <paramdef>XRectangle<parameter> *overall_ink_return</parameter></paramdef>
- <paramdef>XRectangle<parameter> *overall_logical_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_bytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes in the string argument.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_wchars</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the string argument.
-<!-- .ds Ov dimensions -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>overall_ink_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the overall ink dimensions.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>overall_logical_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the overall logical dimensions.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XmbTextExtents</function>
-and
-<function>XwcTextExtents</function>
-functions set the components of the specified overall_ink_return and
-overall_logical_return
-arguments to the overall bounding box of the string's image
-and a logical bounding box for spacing purposes, respectively.
-They return the value returned by
-<function>XmbTextEscapement</function>
-or
-<function>XwcTextEscapement</function>.
-These metrics are relative to the drawing origin of the string,
-using the fonts loaded for the specified font set.
-</para>
-<para>
-<!-- .LP -->
-If the overall_ink_return argument is non-NULL,
-it is set to the bounding box of the string's character ink.
-The overall_ink_return for a nondescending, horizontally drawn
-Latin character is conventionally entirely above the baseline;
-that is, overall_ink_return.height &lt;= -overall_ink_return.y.
-The overall_ink_return for a nonkerned character
-is entirely at, and to the right of, the origin;
-that is, overall_ink_return.x &gt;= 0.
-A character consisting of a single pixel at the origin would set
-overall_ink_return fields y = 0, x = 0, width = 1, and height = 1.
-</para>
-<para>
-<!-- .LP -->
-If the overall_logical_return argument is non-NULL,
-it is set to the bounding box that provides minimum spacing
-to other graphical features for the string.
-Other graphical features, for example, a border surrounding the text,
-should not intersect this rectangle.
-</para>
-<para>
-<!-- .LP -->
-When the
-<type>XFontSet</type>
-has missing charsets,
-metrics for each unavailable character are taken
-from the default string returned by
-<function>XCreateFontSet</function>
-so that the metrics represent the text as it will actually be drawn.
-The behavior for an invalid codepoint is undefined.
-</para>
-<para>
-<!-- .LP -->
-To determine the effective drawing origin for a character in a drawn string,
-the client should call
-<function>XmbTextPerCharExtents</function>
-on the entire string, then on the character,
-and subtract the x values of the returned
-rectangles for the character.
-This is useful to redraw portions of a line of text
-or to justify words, but for context-dependent rendering,
-the client should not assume that it can redraw the character by itself
-and get the same rendering.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain per-character information for a text string,
-use
-<function>XmbTextPerCharExtents</function>
-or
-<function>XwcTextPerCharExtents</function>.
-<indexterm significance="preferred"><primary>XmbTextPerCharExtents</primary></indexterm>
-<indexterm significance="preferred"><primary>XwcTextPerCharExtents</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XmbTextPerCharExtents</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> num_bytes</parameter></paramdef>
- <paramdef>XRectangle<parameter> *ink_array_return</parameter></paramdef>
- <paramdef>XRectangle<parameter> *logical_array_return</parameter></paramdef>
- <paramdef>int<parameter> array_size</parameter></paramdef>
- <paramdef>int<parameter> *num_chars_return</parameter></paramdef>
- <paramdef>XRectangle<parameter> *overall_ink_return</parameter></paramdef>
- <paramdef>XRectangle<parameter> *overall_logical_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XwcTextPerCharExtents</function></funcdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
- <paramdef>wchar_t<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> num_wchars</parameter></paramdef>
- <paramdef>XRectangle<parameter> *ink_array_return</parameter></paramdef>
- <paramdef>XRectangle<parameter> *logical_array_return</parameter></paramdef>
- <paramdef>int<parameter> array_size</parameter></paramdef>
- <paramdef>int<parameter> *num_chars_return</parameter></paramdef>
- <paramdef>XRectangle<parameter> *overall_ink_return</parameter></paramdef>
- <paramdef>XRectangle<parameter> *overall_logical_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_bytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes in the string argument.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_wchars</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the string argument.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>ink_array_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the ink dimensions for each character.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>logical_array_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the logical dimensions for each character.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>array_size</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the size of ink_array_return and logical_array_return.
-The caller must pass in arrays of this size.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_chars_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of characters in the string argument.
-<!-- .ds Ov extents of the entire string -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>overall_ink_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the overall ink dimensions.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>overall_logical_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the overall logical dimensions.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XmbTextPerCharExtents</function>
-and
-<function>XwcTextPerCharExtents</function>
-functions return the text dimensions of each character of the specified text,
-using the fonts loaded for the specified font set.
-Each successive element of ink_array_return and logical_array_return
-is set to the successive character's drawn metrics,
-relative to the drawing origin of the string and one
-rectangle
-for each character in the supplied text string.
-The number of elements of ink_array_return and logical_array_return
-that have been set is returned to num_chars_return.
-</para>
-<para>
-<!-- .LP -->
-Each element of ink_array_return is set to the bounding box
-of the corresponding character's drawn foreground color.
-Each element of logical_array_return is set to the bounding box
-that provides minimum spacing to other graphical features
-for the corresponding character.
-Other graphical features should not intersect any of the
-logical_array_return rectangles.
-</para>
-<para>
-<!-- .LP -->
-Note that an
-<structname>XRectangle</structname>
-represents the effective drawing dimensions of the character,
-regardless of the number of font glyphs that are used to draw
-the character or the direction in which the character is drawn.
-If multiple characters map to a single character glyph,
-the dimensions of all the
-<structname>XRectangle</structname>s
-of those characters are the same.
-</para>
-<para>
-<!-- .LP -->
-When the
-<type>XFontSet</type>
-has missing charsets, metrics for each unavailable
-character are taken from the default string returned by
-<function>XCreateFontSet</function>
-so that the metrics represent the text as it will actually be drawn.
-The behavior for an invalid codepoint is undefined.
-</para>
-<para>
-<!-- .LP -->
-If the array_size is too small for the number of characters in the
-supplied text, the functions return zero
-and num_chars_return is set to the number of rectangles required.
-Otherwise, the functions return a nonzero value.
-</para>
-<para>
-<!-- .LP -->
-If the overall_ink_return or overall_logical_return argument is non-NULL,
-<function>XmbTextPerCharExtents</function>
-and
-<function>XwcTextPerCharExtents</function>
-return the maximum extent of the string's metrics to overall_ink_return
-or overall_logical_return, as returned by
-<function>XmbTextExtents</function>
-or
-<function>XwcTextExtents</function>.
-</para>
-</sect2>
-<sect2 id="Drawing_Text_Using_Font_Sets">
-<title>Drawing Text Using Font Sets</title>
-<!-- .XS -->
-<!-- (SN Drawing Text Using Font Sets -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The functions defined in this section
-draw text at a specified location in a drawable.
-They are similar to the functions
-<function>XDrawText</function>,
-<function>XDrawString</function>,
-and
-<function>XDrawImageString</function>
-except that they work with font sets instead of single fonts
-and interpret the text based on the locale of the font set
-instead of treating the bytes of the string as direct font indexes.
-See section 8.6 for details of the use of Graphics Contexts (GCs)
-and possible protocol errors.
-If a
-<errorname>BadFont</errorname>
-error is generated,
-characters prior to the offending character may have been drawn.
-</para>
-<para>
-<!-- .LP -->
-The text is drawn using the fonts loaded for the specified font set;
-the font in the GC is ignored and may be modified by the functions.
-No validation that all fonts conform to some width rule is performed.
-</para>
-<para>
-<!-- .LP -->
-The text functions
-<function>XmbDrawText</function>
-and
-<function>XwcDrawText</function>
-use the following structures:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XmbTextItem</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- char *chars; /* pointer to string */
- int nchars; /* number of bytes */
- int delta; /* pixel delta between strings */
- XFontSet font_set; /* fonts, None means don't change */
-} XmbTextItem;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XwcTextItem</primary></indexterm>
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- wchar_t *chars; /* pointer to wide char string */
- int nchars; /* number of wide characters */
- int delta; /* pixel delta between strings */
- XFontSet font_set; /* fonts, None means don't change */
-} XwcTextItem;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To draw text using multiple font sets in a given drawable, use
-<function>XmbDrawText</function>
-or
-<function>XwcDrawText</function>.
-<indexterm significance="preferred"><primary>XmbDrawText</primary></indexterm>
-<indexterm significance="preferred"><primary>XwcDrawText</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XmbDrawText</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>XmbTextItem<parameter> *items</parameter></paramdef>
- <paramdef>int<parameter> nitems</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XwcDrawText</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>XwcTextItem<parameter> *items</parameter></paramdef>
- <paramdef>int<parameter> nitems</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>items</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of text items.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nitems</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of text items in the array.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XmbDrawText</function>
-and
-<function>XwcDrawText</function>
-functions allow complex spacing and font set shifts between text strings.
-Each text item is processed in turn, with the origin of a text
-element advanced in the primary draw direction by the escapement of the
-previous text item.
-A text item delta specifies an additional escapement of the text item
-drawing origin in the primary draw direction.
-A font_set member other than
-<symbol>None</symbol>
-in an item causes the font set to be used for this and subsequent text items
-in the text_items list.
-Leading text items with a font_set member set to
-<symbol>None</symbol>
-will not be drawn.
-</para>
-<para>
-<!-- .LP -->
-<function>XmbDrawText</function>
-and
-<function>XwcDrawText</function>
-do not perform any context-dependent rendering between text segments.
-Clients may compute the drawing metrics by passing each text segment to
-<function>XmbTextExtents</function>
-and
-<function>XwcTextExtents</function>
-or
-<function>XmbTextPerCharExtents</function>
-and
-<function>XwcTextPerCharExtents</function>.
-When the
-<type>XFontSet</type>
-has missing charsets, each unavailable character is drawn
-with the default string returned by
-<function>XCreateFontSet</function>.
-The behavior for an invalid codepoint is undefined.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To draw text using a single font set in a given drawable, use
-<function>XmbDrawString</function>
-or
-<function>XwcDrawString</function>.
-<indexterm significance="preferred"><primary>XmbDrawString</primary></indexterm>
-<indexterm significance="preferred"><primary>XwcDrawString</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XmbDrawString</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> num_bytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XwcDrawString</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>wchar_t<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> num_wchars</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_bytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes in the string argument.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_wchars</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the string argument.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XmbDrawString</function>
-and
-<function>XwcDrawString</function>
-functions draw the specified text with the foreground pixel.
-When the
-<type>XFontSet</type>
-has missing charsets, each unavailable character is drawn
-with the default string returned by
-<function>XCreateFontSet</function>.
-The behavior for an invalid codepoint is undefined.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To draw image text using a single font set in a given drawable, use
-<function>XmbDrawImageString</function>
-or
-<function>XwcDrawImageString</function>.
-<indexterm significance="preferred"><primary>XmbDrawImageString</primary></indexterm>
-<indexterm significance="preferred"><primary>XwcDrawImageString</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XmbDrawImageString</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> num_bytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XwcDrawImageString</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>wchar_t<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> num_wchars</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>font_set</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the font set.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
-<!-- .ds Xy -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the character string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_bytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes in the string argument.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_wchars</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of characters in the string argument.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XmbDrawImageString</function>
-and
-<function>XwcDrawImageString</function>
-functions fill a destination rectangle with the background pixel defined
-in the GC and then paint the text with the foreground pixel.
-The filled rectangle is the rectangle returned to overall_logical_return by
-<function>XmbTextExtents</function>
-or
-<function>XwcTextExtents</function>
-for the same text and
-<type>XFontSet</type>.
-</para>
-<para>
-<!-- .LP -->
-When the
-<type>XFontSet</type>
-has missing charsets, each unavailable character is drawn
-with the default string returned by
-<function>XCreateFontSet</function>.
-The behavior for an invalid codepoint is undefined.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Input_Methods">
-<title>Input Methods</title>
-<!-- .XS -->
-<!-- (SN Input Methods -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This section provides discussions of the following X Input Method
-(<acronym>XIM</acronym>) topics:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Input method overview
- </para>
- </listitem>
- <listitem>
- <para>
-Input method management
- </para>
- </listitem>
- <listitem>
- <para>
-Input method functions
- </para>
- </listitem>
- <listitem>
- <para>
-Input method values
- </para>
- </listitem>
- <listitem>
- <para>
-Input context functions
- </para>
- </listitem>
- <listitem>
- <para>
-Input context values
- </para>
- </listitem>
- <listitem>
- <para>
-Input method callback semantics
- </para>
- </listitem>
- <listitem>
- <para>
-Event filtering
- </para>
- </listitem>
- <listitem>
- <para>
-Getting keyboard input
- </para>
- </listitem>
- <listitem>
- <para>
-Input method conventions
- </para>
- </listitem>
-</itemizedlist>
-<sect2 id="Input_Method_Overview">
-<title>Input Method Overview</title>
-<!-- .XS -->
-<!-- (SN Input Method Overview -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This section provides definitions for terms and concepts used
-for internationalized text input and a brief overview of the
-intended use of the mechanisms provided by Xlib.
-</para>
-<para>
-<!-- .LP -->
-A large number of languages in the world use alphabets
-consisting of a small set of symbols (letters) to form words.
-To enter text into a computer in an alphabetic language,
-a user usually has a keyboard on which there exist key symbols corresponding
-to the alphabet.
-Sometimes, a few characters of an alphabetic language are missing
-on the keyboard.
-Many computer users who speak a Latin-alphabet-based language
-only have an English-based keyboard.
-They need to hit a combination of keystrokes
-to enter a character that does not exist directly on the keyboard.
-A number of algorithms have been developed for entering such characters.
-These are known as European input methods, compose input methods,
-or dead-key input methods.
-</para>
-<para>
-<!-- .LP -->
-Japanese is an example of a language with a phonetic symbol set,
-where each symbol represents a specific sound.
-There are two phonetic symbol sets in Japanese: Katakana and Hiragana.
-In general,
-Katakana is used for words that are of foreign origin,
-and Hiragana is used for writing native Japanese words.
-Collectively, the two systems are called Kana.
-Each set consists of 48 characters.
-</para>
-<para>
-<!-- .LP -->
-Korean also has a phonetic symbol set, called Hangul.
-Each of the 24 basic phonetic symbols (14 consonants and 10 vowels)
-represents a specific sound.
-A syllable is composed of two or three parts:
-the initial consonants, the vowels, and the optional last consonants.
-With Hangul,
-syllables can be treated as the basic units on which text processing is done.
-For example,
-a delete operation may work on a phonetic symbol or a syllable.
-Korean code sets include several thousands of these syllables.
-A user types the phonetic symbols that make up the syllables of the words
-to be entered.
-The display may change as each phonetic symbol is entered.
-For example,
-when the second phonetic symbol of a syllable is entered,
-the first phonetic symbol may change its shape and size.
-Likewise, when the third phonetic symbol is entered,
-the first two phonetic symbols may change their shape and size.
-</para>
-<para>
-<!-- .LP -->
-Not all languages rely solely on alphabetic or phonetic systems.
-Some languages, including Japanese and Korean, employ an
-ideographic writing system.
-In an ideographic system, rather than taking a small set of
-symbols and combining them in different ways to create words,
-each word consists of one unique symbol (or, occasionally, several symbols).
-The number of symbols can be very large:
-approximately 50,000 have been identified in Hanzi,
-the Chinese ideographic system.
-</para>
-<para>
-<!-- .LP -->
-Two major aspects of ideographic systems impact their use with computers.
-First, the standard computer character sets in Japan, China, and Korea
-include roughly 8,000 characters,
-while sets in Taiwan have between 15,000 and 30,000 characters.
-This makes it necessary to use more than one byte to represent a character.
-Second, it obviously is impractical to have a keyboard that includes
-all of a given language's ideographic symbols.
-Therefore, a mechanism is required for entering characters
-so that a keyboard with a reasonable number of keys can be used.
-Those input methods are usually based on phonetics,
-but there also exist methods based on the graphical properties of
-characters.
-</para>
-<para>
-<!-- .LP -->
-In Japan, both Kana and the ideographic system Kanji are used.
-In Korea, Hangul and sometimes the ideographic system Hanja are used.
-Now consider entering ideographs in Japan, Korea, China, and Taiwan.
-</para>
-<para>
-<!-- .LP -->
-In Japan, either Kana or English characters are typed and then a region
-is selected (sometimes automatically) for conversion to Kanji.
-Several Kanji characters may have the same phonetic representation.
-If that is the case with the string entered,
-a menu of characters is presented and
-the user must choose the appropriate one.
-If no choice is necessary or a preference has been established,
-the input method does the substitution directly.
-When Latin characters are converted to Kana or Kanji,
-it is called a romaji conversion.
-</para>
-<para>
-<!-- .LP -->
-In Korea, it is usually acceptable to keep Korean text in Hangul form,
-but some people may choose to write Hanja-originated words in Hanja
-rather than in Hangul.
-To change Hangul to Hanja,
-the user selects a region for conversion
-and then follows the same basic method as that described for Japanese.
-</para>
-<para>
-<!-- .LP -->
-Probably because there are well-accepted phonetic writing systems
-for Japanese and Korean,
-computer input methods in these countries for entering ideographs
-are fairly standard.
-Keyboard keys have both English characters and phonetic symbols
-engraved on them, and the user can switch between the two sets.
-</para>
-<para>
-<!-- .LP -->
-The situation is different for Chinese.
-While there is a phonetic system called Pinyin promoted by authorities,
-there is no consensus for entering Chinese text.
-Some vendors use a phonetic decomposition (Pinyin or another),
-others use ideographic decomposition of Chinese words,
-with various implementations and keyboard layouts.
-There are about 16 known methods, none of which is a clear standard.
-</para>
-<para>
-<!-- .LP -->
-Also, there are actually two ideographic sets used:
-Traditional Chinese (the original written Chinese)
-and Simplified Chinese.
-Several years ago,
-the People's Republic of China launched a campaign to simplify
-some ideographic characters and eliminate redundancies altogether.
-Under the plan,
-characters would be streamlined every five years.
-Characters have been revised several times now,
-resulting in the smaller, simpler set that makes up Simplified Chinese.
-</para>
-<sect3 id="Input_Method_Architecture">
-<title>Input Method Architecture</title>
-<!-- .XS -->
-<!-- (SN Input Method Architecture -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-As shown in the previous section,
-there are many different input methods in use today,
-each varying with language, culture, and history.
-A common feature of many input methods is that the user may type
-multiple keystrokes to compose a single character (or set
-of characters).
-The process of composing characters from keystrokes is called
-<emphasis remap='I'>preediting</emphasis>.
-It may require complex algorithms and large dictionaries
-involving substantial computer resources.
-</para>
-<para>
-<!-- .LP -->
-Input methods may require one or more areas in which to show the
-feedback of the actual keystrokes, to propose disambiguation to the
-user, to list dictionaries, and so on.
-The input method areas of concern are as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The <emphasis remap='I'>status</emphasis> area is a logical extension of the
-LEDs that exist on the physical keyboard.
-It is a window that is intended to present the internal state
-of the input method that is critical to the user.
-The status area may consist of text data and bitmaps or some combination.
- </para>
- </listitem>
- <listitem>
- <para>
-The <emphasis remap='I'>preedit</emphasis> area displays the
-intermediate text for those languages that are composing prior to
-the client handling the data.
- </para>
- </listitem>
- <listitem>
- <para>
-The <emphasis remap='I'>auxiliary</emphasis> area is used for pop-up menus and customizing
-dialogs that may be required for an input method.
-There may be multiple auxiliary areas for an input method.
-Auxiliary areas are managed by the input method independent of the client.
-Auxiliary areas are assumed to be separate dialogs,
-which are maintained by the input method.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-There are various user interaction styles used for preediting.
-The ones supported by Xlib are as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-For <emphasis remap='I'>on-the-spot</emphasis> input methods,
-preediting data will be displayed directly in the application window.
-Application data is moved to allow preedit data to appear
-at the point of insertion.
- </para>
- </listitem>
- <listitem>
- <para>
-<emphasis remap='I'>Over-the-spot</emphasis> preediting means that the data is displayed in
-a preedit window that is placed over the point of insertion.
- </para>
- </listitem>
- <listitem>
- <para>
-<emphasis remap='I'>Off-the-spot</emphasis> preediting means that the preedit window is
-inside the application window but not at the point of insertion.
-Often, this type of window is placed at the bottom of the application window.
- </para>
- </listitem>
- <listitem>
- <para>
-<emphasis remap='I'>Root-window</emphasis> preediting refers to input methods that use a preedit
-window that is the child of
-<function>RootWindow</function>.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-It would require a lot of computing resources if portable applications
-had to include input methods for all the languages in the world.
-To avoid this,
-a goal of the Xlib design is to allow an application
-to communicate with an input method placed in a separate process.
-Such a process is called an <emphasis remap='I'>input server</emphasis>.
-The server to which the application should connect is dependent on
-the environment when the application is started up,
-that is, the user language and the actual encoding to be used for it.
-The input method connection is said to be <emphasis remap='I'>locale-dependent</emphasis>.
-It is also user-dependent.
-For a given language, the user can choose, to some extent,
-the user interface style of input method (if choice is possible among
-several).
-</para>
-<para>
-<!-- .LP -->
-Using an input server implies communication overhead,
-but applications can be migrated without relinking.
-Input methods can be implemented either as a
-stub communicating to an input server or as a local library.
-</para>
-<para>
-<!-- .LP -->
-An input method may be based on a <emphasis remap='I'>front-end</emphasis> or a <emphasis remap='I'>back-end</emphasis>
-architecture.
-In a front-end architecture,
-there are two separate connections to the X server:
-keystrokes go directly from the X server to the input method on
-one connection and other events to the regular client connection.
-The input method is then acting as a filter and sends composed strings
-to the client.
-A front-end architecture requires synchronization between the
-two connections to avoid lost key events or locking issues.
-</para>
-<para>
-<!-- .LP -->
-In a back-end architecture,
-a single X server connection is used.
-A dispatching mechanism must decide on this channel to delegate appropriate
-keystrokes to the input method.
-For instance,
-it may retain a Help keystroke for its own purpose.
-In the case where the input method is a separate process (that is, a server),
-there must be a special communication protocol between the back-end client
-and the input server.
-</para>
-<para>
-<!-- .LP -->
-A front-end architecture introduces synchronization issues
-and a filtering mechanism for noncharacter keystrokes
-(Function keys, Help, and so on).
-A back-end architecture sometimes implies more communication overhead
-and more process switching.
-If all three processes (X server, input server, client)
-are running on a single workstation,
-there are two process switches for each keystroke in a back-end
-architecture,
-but there is only one in a front-end architecture.
-</para>
-<para>
-<!-- .LP -->
-The abstraction used by a client to communicate with an input method
-is an opaque data structure represented by the
-<type>XIM</type>
-data type.
-This data structure is returned by the
-<function>XOpenIM</function>
-function, which opens an input method on a given display.
-Subsequent operations on this data structure encapsulate all communication
-between client and input method.
-There is no need for an X client to use any networking library
-or natural language package to use an input method.
-</para>
-<para>
-<!-- .LP -->
-A single input server may be used for one or more languages,
-supporting one or more encoding schemes.
-But the strings returned from an input method will always be encoded
-in the (single) locale associated with the
-<type>XIM</type>
-object.
-</para>
-</sect3>
-<sect3 id="Input_Contexts">
-<title>Input Contexts</title>
-<!-- .XS -->
-<!-- (SN Input Contexts -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides the ability to manage a multi-threaded state for text input.
-A client may be using multiple windows,
-each window with multiple text entry areas,
-and the user possibly switching among them at any time.
-The abstraction for representing the state of a particular input thread
-is called an <emphasis remap='I'>input context</emphasis>.
-The Xlib representation of an input context is an
-<type>XIC</type>.
-</para>
-<para>
-<!-- .LP -->
-An input context is the abstraction retaining the state, properties,
-and semantics of communication between a client and an input method.
-An input context is a combination of an input method, a locale
-specifying the encoding of the character strings to be returned,
-a client window, internal state information,
-and various layout or appearance characteristics.
-The input context concept somewhat matches for input the graphics context
-abstraction defined for graphics output.
-</para>
-<para>
-<!-- .LP -->
-One input context belongs to exactly one input method.
-Different input contexts may be associated with the same input method,
-possibly with the same client window.
-An
-<type>XIC</type>
-is created with the
-<function>XCreateIC</function>
-function, providing an
-<type>XIM</type>
-argument and affiliating the input context to the input method
-for its lifetime.
-When an input method is closed with
-<function>XCloseIM</function>,
-all of its affiliated input contexts should not be used any more
-(and should preferably be destroyed before closing the input method).
-</para>
-<para>
-<!-- .LP -->
-Considering the example of a client window with multiple text entry areas,
-the application programmer could, for example, choose to implement as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-As many input contexts are created as text entry areas, and the client
-will get the input accumulated on each context each time it looks up
-in that context.
- </para>
- </listitem>
- <listitem>
- <para>
-A single context is created for a top-level window in the application.
-If such a window contains several text entry areas,
-each time the user moves to another text entry area,
-the client has to indicate changes in the context.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-A range of choices can be made by application designers to use
-either a single or multiple input contexts,
-according to the needs of their application.
-</para>
-</sect3>
-<sect3 id="Getting_Keyboard_Input">
-<title>Getting Keyboard Input</title>
-<!-- .XS -->
-<!-- (SN Getting Keyboard Input -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To obtain characters from an input method,
-a client must call the function
-<function>XmbLookupString</function>
-or
-<function>XwcLookupString</function>
-with an input context created from that input method.
-Both a locale and display are bound to an input method when it is opened,
-and an input context inherits this locale and display.
-Any strings returned by
-<function>XmbLookupString</function>
-or
-<function>XwcLookupString</function>
-will be encoded in that locale.
-</para>
-</sect3>
-<sect3 id="Focus_Management">
-<title>Focus Management</title>
-<!-- .XS -->
-<!-- (SN Focus Management -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-For each text entry area in which the
-<function>XmbLookupString</function>
-or
-<function>XwcLookupString</function>
-functions are used,
-there will be an associated input context.
-</para>
-<para>
-<!-- .LP -->
-When the application focus moves to a text entry area,
-the application must set the input context focus to the
-input context associated with that area.
-The input context focus is set by calling
-<function>XSetICFocus</function>
-with the appropriate input context.
-</para>
-<para>
-<!-- .LP -->
-Also, when the application focus moves out of a text entry area, the
-application should unset the focus for the associated input context
-by calling
-<function>XUnsetICFocus</function>.
-As an optimization, if
-<function>XSetICFocus</function>
-is called successively on two different input contexts,
-setting the focus on the second
-will automatically unset the focus on the first.
-</para>
-<para>
-<!-- .LP -->
-To set and unset the input context focus correctly,
-it is necessary to track application-level focus changes.
-Such focus changes do not necessarily correspond to X server focus changes.
-</para>
-<para>
-<!-- .LP -->
-If a single input context
-is being used to do input for
-multiple text entry areas, it will also be necessary
-to set the focus window of the
-input context whenever the focus window changes
-(see section 13.5.6.3).
-</para>
-</sect3>
-<sect3 id="Geometry_Management">
-<title>Geometry Management</title>
-<!-- .XS -->
-<!-- (SN Geometry Management -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-In most input method architectures
-(on-the-spot being the notable exception),
-the input method will perform the display of its own data.
-To provide better visual locality,
-it is often desirable to have the input method areas embedded within a client.
-To do this,
-the client may need to allocate space for an input method.
-Xlib provides support that allows the size and position of input method
-areas to be provided by a client.
-The input method areas that are supported for geometry management
-are the status area and the preedit area.
-</para>
-<para>
-<!-- .LP -->
-The fundamental concept on which geometry management for input method windows
-is based is the proper division of responsibilities between the
-client (or toolkit) and the input method.
-The division of responsibilities is as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The client is responsible for the geometry of the input method window.
- </para>
- </listitem>
- <listitem>
- <para>
-The input method is responsible for the contents of the input method window.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-An input method is able to suggest a size to the client,
-but it cannot suggest a placement.
-Also the input method can only suggest a size.
-It does not determine the size,
-and it must accept the size it is given.
-</para>
-<para>
-<!-- .LP -->
-Before a client provides geometry management for an input method,
-it must determine if geometry management is needed.
-The input method indicates the need for geometry management
-by setting
-<symbol>XIMPreeditArea</symbol>
-or
-<symbol>XIMStatusArea</symbol>
-in its
-<structname>XIMStyles</structname>
-value returned by
-<function>XGetIMValues</function>.
-When a client has decided that it will provide geometry management
-for an input method,
-it indicates that decision by setting the
-<symbol>XNInputStyle</symbol>
-value in the
-<type>XIC</type>.
-</para>
-<para>
-<!-- .LP -->
-After a client has established with the input method
-that it will do geometry management,
-the client must negotiate the geometry with the input method.
-The geometry is negotiated by the following steps:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The client suggests an area to the input method by setting the
-<symbol>XNAreaNeeded</symbol>
-value for that area.
-If the client has no constraints for the input method,
-it either will not suggest an area or will set the width and height to zero.
-Otherwise, it will set one of the values.
- </para>
- </listitem>
- <listitem>
- <para>
-The client will get the <acronym>XIC</acronym> value
-<symbol>XNAreaNeeded</symbol>.
-The input method will return its suggested size in this value.
-The input method should pay attention to any constraints suggested
-by the client.
- </para>
- </listitem>
- <listitem>
- <para>
-The client sets the <acronym>XIC</acronym> value
-<symbol>XNArea</symbol>
-to inform the input method of the geometry of its window.
-The client should try to honor the geometry requested by the input method.
-The input method must accept this geometry.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Clients doing geometry management must be aware that setting other
-<acronym>XIC</acronym> values may affect the geometry desired by an input method.
-For example,
-<symbol>XNFontSet</symbol>
-and
-<symbol>XNLineSpace</symbol>
-may change the geometry desired by the input method.
-</para>
-<para>
-<!-- .LP -->
-The table of <acronym>XIC</acronym> values (see section 13.5.6)
-indicates the values that can cause the desired geometry to change
-when they are set.
-It is the responsibility of the client to renegotiate the geometry
-of the input method window when it is needed.
-</para>
-<para>
-<!-- .LP -->
-In addition,
-a geometry management callback is provided
-by which an input method can initiate a geometry change.
-</para>
-</sect3>
-<sect3 id="Event_Filtering">
-<title>Event Filtering</title>
-<!-- .XS -->
-<!-- (SN Event Filtering -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-A filtering mechanism is provided to allow input methods
-to capture X events transparently to clients.
-It is expected that toolkits (or clients) using
-<function>XmbLookupString</function>
-or
-<function>XwcLookupString</function>
-will call this filter at some point in the event processing mechanism
-to make sure that events needed by an input method can be filtered
-by that input method.
-</para>
-<para>
-<!-- .LP -->
-If there were no filter,
-a client could receive and discard events that are necessary
-for the proper functioning of an input method.
-The following provides a few examples of such events:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Expose events on preedit window in local mode.
- </para>
- </listitem>
- <listitem>
- <para>
-Events may be used by an input method to communicate with an input server.
-Such input server protocol-related events have to be intercepted
-if one does not want to disturb client code.
- </para>
- </listitem>
- <listitem>
- <para>
-Key events can be sent to a filter before they are bound
-to translations such as those the X Toolkit Intrinsics library provides.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Clients are expected to get the <acronym>XIC</acronym> value
-<symbol>XNFilterEvents</symbol>
-and augment the event mask for the client window with that event mask.
-This mask may be zero.
-</para>
-</sect3>
-<sect3 id="Callbacks">
-<title>Callbacks</title>
-<!-- .XS -->
-<!-- (SN Callbacks -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-When an on-the-spot input method is implemented,
-only the client can insert or delete preedit data in place
-and possibly scroll existing text.
-This means that the echo of the keystrokes has to be achieved
-by the client itself, tightly coupled with the input method logic.
-</para>
-<para>
-<!-- .LP -->
-When the user enters a keystroke,
-the client calls
-<function>XmbLookupString</function>
-or
-<function>XwcLookupString</function>.
-At this point, in the on-the-spot case,
-the echo of the keystroke in the preedit has not yet been done.
-Before returning to the client logic that handles the input characters,
-the look-up function
-must call the echoing logic to insert the new keystroke.
-If the keystrokes entered so far make up a character,
-the keystrokes entered need to be deleted,
-and the composed character will be returned.
-Hence, what happens is that, while being called by client code,
-the input method logic has to call back to the client before it returns.
-The client code, that is, a callback procedure,
-is called from the input method logic.
-</para>
-<para>
-<!-- .LP -->
-There are a number of cases where the input method logic has to
-call back the client.
-Each of those cases is associated with a well-defined callback action.
-It is possible for the client to specify, for each input context,
-what callback is to be called for each action.
-</para>
-<para>
-<!-- .LP -->
-There are also callbacks provided for feedback of status information
-and a callback to initiate a geometry request for an input method.
-</para>
-</sect3>
-<sect3 id="Visible_Position_Feedback_Masks">
-<title>Visible Position Feedback Masks</title>
-<!-- .XS -->
-<!-- (SN Visible Position Feedback Masks -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-In the on-the-spot input style, there is a problem when
-attempting to draw preedit strings that are longer than the
-available space. Once the display area is exceeded, it is not
-clear how best to display the preedit string.
-The visible position feedback masks of
-<structname>XIMText</structname>
-help resolve this problem by allowing the input method to specify hints that
-indicate the essential portions of the preedit string.
-For example, such hints can help developers implement
-scrolling of a long preedit string within a short preedit display area.
-</para>
-</sect3>
-<sect3 id="Preedit_String_Management">
-<title>Preedit String Management</title>
-<!-- .XS -->
-<!-- (SN Preedit String Management -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-As highlighted before, the input method architecture provides
-preediting, which supports a type of preprocessor input composition.
-In this case, composition consists of interpreting a sequence
-of key events and returning a committed string via
-<function>XmbLookupString</function>
-or
-<function>XwcLookupString</function>.
-This provides the basics for input methods.
-</para>
-<para>
-<!-- .LP -->
-In addition to preediting based on key events, a general framework
-is provided to give a client that desires it more advanced preediting based
-on the text within the client. This framework is called
-<emphasis remap='I'>string conversion</emphasis> and is provided using <acronym>XIC</acronym> values.
-The fundamental concept of string conversion
-is to allow the input method to manipulate the client's
-text independent of any user preediting operation.
-</para>
-<para>
-<!-- .LP -->
-The need for string conversion is based on
-language needs and input method capabilities.
-The following are some examples of string conversion:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Transliteration conversion provides language-specific conversions
-within the input method.
-In the case of Korean input, users wish to convert a Hangul string
-into a Hanja string while in preediting, after preediting,
-or in other situations (for example, on a selected string).
-The conversion is triggered when the user
-presses a Hangul-to-Hanja key sequence (which may be input method specific).
-Sometimes the user may want to invoke the conversion after finishing
-preediting or on a user-selected string.
-Thus, the string to be converted is in an application buffer, not in
-the preedit area of the input method. The string conversion services
-allow the client to request this transliteration conversion from the
-input method.
-There are many other transliteration conversions defined for
-various languages, for example, Kana-to-Kanji conversion in Japanese.
-<!-- .sp -->
-The key to remember is that transliteration conversions are triggered
-at the request of the user and returned to the client
-immediately without affecting the preedit area of the input method.
- </para>
- </listitem>
- <listitem>
- <para>
-Reconversion of a previously committed string or
-a selected string is supported by many input methods as a
-convenience to the user.
-For example, a user tends to mistype the commit key while
-preediting. In that case, some input methods provide a special
-key sequence to request a ``reconvert'' operation on the
-committed string, similiar to the undo facility provided by most
-text editors.
-Another example is where the user is proofreading a document
-that has some misconversions from preediting and wants to correct
-the misconverted text. Such reconversion is again triggered
-by the user invoking some special action, but reconversions should
-not affect the state of the preedit area.
- </para>
- </listitem>
- <listitem>
- <para>
-Context-sensitive conversion is required for some languages
-and input methods that need to retrieve text that surrounds the
-current spot location (cursor position) of the client's buffer.
-Such text is needed when the preediting operation depends on
-some surrounding characters (usually preceding the spot location).
-For example,
-in Thai language input, certain character sequences may be invalid and
-the input method may want to check whether characters constitute a
-valid word. Input methods that do such context-dependent
-checking need to retrieve the characters surrounding the current
-cursor position to obtain complete words.
-<!-- .sp -->
-Unlike other conversions, this conversion is not explicitly
-requested by the user.
-Input methods that provide such context-sensitive conversion
-continuously need to request context from the client, and any change
-in the context of the spot location may affect such conversions.
-The client's context would be needed if the user moves the cursor
-and starts editing again.
-<!-- .sp -->
-For this reason, an input method supporting this type of conversion
-should take notice of when the client calls
-<function>XmbResetIC</function>
-or
-<function>XwcResetIC</function>,
-which is usually an indication of a context change.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Context-sensitive conversions just need a copy of the client's text,
-while other conversions replace the client's text with new text
-to achieve the reconversion or transliteration. Yet in all
-cases the result of a conversion, either immediately or via preediting,
-is returned by the
-<function>XmbLookupString</function>
-and
-<function>XwcLookupString</function>
-functions.
-</para>
-<para>
-<!-- .LP -->
-String conversion support is dependent on the availability of the
-<symbol>XNStringConversion</symbol>
-or
-<symbol>XNStringConversionCallback</symbol>
-<acronym>XIC</acronym> values.
-Because the input method may not support string conversions,
-clients have to query the availability of string conversion
-operations by checking the supported <acronym>XIC</acronym> values list by calling
-<function>XGetIMValues</function>
-with the
-<symbol>XNQueryICValuesList</symbol>
-IM value.
-</para>
-<para>
-<!-- .LP -->
-The difference between these two values is whether the
-conversion is invoked by the client or the input method.
-The
-<symbol>XNStringConversion</symbol>
-<acronym>XIC</acronym> value is used by clients to request
-a string conversion from the input method. The client
-is responsible for determining which events are used
-to trigger the string conversion and whether the string to be
-converted should be copied or deleted. The type of conversion
-is determined by the input method; the client can only
-pass the string to be converted. The client is guaranteed that
-no
-<symbol>XNStringConversionCallback</symbol>
-will be issued when this value is set; thus, the client need
-only set one of these values.
-</para>
-<para>
-<!-- .LP -->
-The
-<symbol>XNStringConversionCallback</symbol>
-<acronym>XIC</acronym> value is used by the client to notify the input method that
-it will accept requests from the input method for string conversion.
-If this value is set,
-it is the input method's responsibility to determine which
-events are used to trigger the string conversion.
-When such events occur, the input method issues a call to the
-client-supplied procedure to retrieve the string to be converted. The client's
-callback procedure is notified whether to copy or delete the string and
-is provided with hints as to the amount of text needed.
-The
-<structname>XIMStringConversionCallbackStruct</structname>
-specifies which text should be passed back to the input method.
-</para>
-<para>
-<!-- .LP -->
-Finally, the input method may call the client's
-<symbol>XNStringConversionCallback</symbol>
-procedure multiple times if the string returned from the callback is
-not sufficient to perform a successful conversion. The arguments
-to the client's procedure allow the input method to define a
-position (in character units) relative to the client's cursor position
-and the size of the text needed. By varying the position and size of
-the desired text in subsequent callbacks, the input method can retrieve
-additional text.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-</sect2>
-<sect2 id="Input_Method_Management">
-<title>Input Method Management</title>
-<!-- .XS -->
-<!-- (SN Input Method Management -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The interface to input methods might appear to be simply creating
-an input method
-(<function>XOpenIM</function>)
-and freeing an input method
-(<function>XCloseIM</function>).
-However, input methods may
-require complex communication with input method servers (IM servers),
-for example:
-</para>
-
-<itemizedlist>
- <listitem>
- <para>
-If the X server, IM server, and X clients are started asynchronously,
-some clients may attempt to connect to the IM server before it is
-fully operational, and fail.
-Therefore, some mechanism is needed to allow clients to detect when an IM
-server has started.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-It is up to clients to decide what should be done when an IM server is
-not available (for example, wait, or use some other IM server).
-</para>
-<para>
-<!-- .LP -->
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Some input methods may allow the underlying IM server to be switched.
-Such customization may be desired without restarting the entire client.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-To support management of input methods in these cases, the following
-functions are provided:
-</para>
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <tbody>
- <row>
- <entry><function>XRegisterIMInstantiateCallback</function></entry>
- <entry>This function allows clients to register a callback procedure
- to be called when Xlib detects that an IM server is up and available.</entry>
- </row>
- <row>
- <entry><function>XOpenIM</function></entry>
- <entry>A client calls this function as a result of the callback procedure
- being called.</entry>
- </row>
- <row>
- <entry><function>XSetIMValues</function>, <function>XSetICValues</function></entry>
- <entry>These functions use the <acronym>XIM</acronym> and <acronym>XIC</acronym> values,
- <symbol>XNDestroyCallback</symbol>,
- to allow a client
- to register a callback procedure to be called when Xlib detects that
- an IM server that was associated with an opened
- input method is no longer available.
- In addition, this function can be used to switch IM servers for those input
- methods that support such functionality. The IM value for switching IM
- servers is implementation-dependent; see the description below about
- switching IM servers.</entry>
- </row>
- <row>
- <entry><function>XUnregisterIMInstantiateCallback</function></entry>
- <entry>This function removes a callback procedure registered by the client.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-Input methods that support switching of IM servers may exhibit some
-side-effects:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The input method will ensure that any new IM server supports any of the
-input styles being used by input contexts already associated with the
-input method.
-However, the list of supported input styles may be different.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Geometry management requests on previously created input contexts
-may be initiated by the new IM server.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-</para>
-<sect3 id="Hot_Keys">
-<title>Hot Keys</title>
-<!-- .XS -->
-<!-- (SN Hot Keys -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Some clients need to guarantee which keys can be used to escape from the
-input method, regardless of the input method state;
-for example, the client-specific Help key or the keys to move the
-input focus.
-The HotKey mechanism allows clients
-to specify a set of keys for this purpose. However, the input
-method might not allow clients to specify hot keys.
-Therefore, clients have to query support of hot keys by checking the
-supported <acronym>XIC</acronym> values list by calling
-<function>XGetIMValues</function>
-with the
-<symbol>XNQueryICValuesList</symbol>
-IM value.
-When the hot keys specified conflict with the key bindings of the
-input method, hot keys take precedence over the key bindings of the input
-method.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-<sect3 id="Preedit_State_Operation">
-<title>Preedit State Operation</title>
-<!-- .XS -->
-<!-- (SN Preedit State Operation -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-An input method may have several internal states, depending on its
-implementation and the locale. However, one state that is
-independent of locale and implementation is whether the input method
-is currently performing a preediting operation.
-Xlib provides the ability for an application to manage the preedit state
-programmatically. Two methods are provided for
-retrieving the preedit state of an input context.
-One method is to query the state by calling
-<function>XGetICValues</function>
-with the
-<symbol>XNPreeditState</symbol>
-<acronym>XIC</acronym> value.
-Another method is to receive notification whenever
-the preedit state is changed. To receive such notification,
-an application needs to register a callback by calling
-<function>XSetICValues</function>
-with the
-<symbol>XNPreeditStateNotifyCallback</symbol>
-<acronym>XIC</acronym> value.
-In order to change the preedit state programmatically, an application
-needs to call
-<function>XSetICValues</function>
-with
-<symbol>XNPreeditState</symbol>.
-</para>
-<para>
-<!-- .LP -->
-Availability of the preedit state is input method dependent. The input
-method may not provide the ability to set the state or to
-retrieve the state programmatically. Therefore, clients have to
-query availability of preedit state operations by checking the
-supported <acronym>XIC</acronym> values list by calling
-<function>XGetIMValues</function>
-with the
-<symbol>XNQueryICValuesList</symbol>
-IM value.
-</para>
-</sect3>
-</sect2>
-<sect2 id="Input_Method_Functions">
-<title>Input Method Functions</title>
-<!-- .XS -->
-<!-- (SN Input Method Functions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To open a connection, use
-<function>XOpenIM</function>.
-<indexterm significance="preferred"><primary>XOpenIM</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XIM <function>XOpenIM</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XrmDatabase<parameter> db</parameter></paramdef>
- <paramdef>char<parameter> *res_name</parameter></paramdef>
- <paramdef>char<parameter> *res_class</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>db</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a pointer to the resource database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>res_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the full resource name of the application.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>res_class</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the full class name of the application.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XOpenIM</function>
-function opens an input method,
-matching the current locale and modifiers specification.
-Current locale and modifiers are bound to the input method at opening time.
-The locale associated with an input method cannot be changed dynamically.
-This implies that the strings returned by
-<function>XmbLookupString</function>
-or
-<function>XwcLookupString</function>,
-for any input context affiliated with a given input method,
-will be encoded in the locale current at the time the input method is opened.
-</para>
-<para>
-<!-- .LP -->
-The specific input method to which this call will be routed
-is identified on the basis of the current locale.
-<function>XOpenIM</function>
-will identify a default input method corresponding to the
-current locale.
-That default can be modified using
-<function>XSetLocaleModifiers</function>
-for the input method modifier.
-</para>
-<para>
-<!-- .LP -->
-The db argument is the resource database to be used by the input method
-for looking up resources that are private to the input method.
-It is not intended that this database be used to look
-up values that can be set as IC values in an input context.
-If db is NULL,
-no database is passed to the input method.
-</para>
-<para>
-<!-- .LP -->
-The res_name and res_class arguments specify the resource name
-and class of the application.
-They are intended to be used as prefixes by the input method
-when looking up resources that are common to all input contexts
-that may be created for this input method.
-The characters used for resource names and classes must be in the
-X Portable Character Set.
-The resources looked up are not fully specified
-if res_name or res_class is NULL.
-</para>
-<para>
-<!-- .LP -->
-The res_name and res_class arguments are not assumed to exist beyond
-the call to
-<function>XOpenIM</function>.
-The specified resource database is assumed to exist for the lifetime
-of the input method.
-</para>
-<para>
-<!-- .LP -->
-<function>XOpenIM</function>
-returns NULL if no input method could be opened.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To close a connection, use
-<function>XCloseIM</function>.
-<indexterm significance="preferred"><primary>XCloseIM</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XCloseIM</function></funcdef>
- <paramdef>XIM<parameter> im</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>im</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input method.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCloseIM</function>
-function closes the specified input method.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set input method attributes, use
-<function>XSetIMValues</function>.
-<indexterm significance="preferred"><primary>XSetIMValues</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XSetIMValues</function></funcdef>
- <paramdef>XIM<parameter> im</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>im</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input method.
-<!-- .ds Al \ to set <acronym>XIM</acronym> values -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- ...
- </term>
- <listitem>
- <para>
-Specifies the variable-length argument list(Al.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetIMValues</function>
-function presents a variable argument list programming interface
-for setting attributes of the specified input method.
-It returns NULL if it succeeds;
-otherwise,
-it returns the name of the first argument that could not be set.
-Xlib does not attempt to set arguments from the supplied list that
-follow the failed argument;
-all arguments in the list preceding the failed argument have been set
-correctly.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To query an input method, use
-<function>XGetIMValues</function>.
-<indexterm significance="preferred"><primary>XGetIMValues</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XGetIMValues</function></funcdef>
- <paramdef>XIM<parameter> im</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>im</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input method.
-<!-- .ds Al \ to get XIM values -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- ...
- </term>
- <listitem>
- <para>
-Specifies the variable length argument list(Al.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetIMValues</function>
-function presents a variable argument list programming interface
-for querying properties or features of the specified input method.
-This function returns NULL if it succeeds;
-otherwise,
-it returns the name of the first argument that could not be obtained.
-</para>
-<para>
-<!-- .LP -->
-Each <acronym>XIM</acronym> value argument (following a name) must point to
-a location where the <acronym>XIM</acronym> value is to be stored.
-That is, if the <acronym>XIM</acronym> value is of type T,
-the argument must be of type T*.
-If T itself is a pointer type,
-then
-<function>XGetIMValues</function>
-allocates memory to store the actual data,
-and the client is responsible for freeing this data by calling
-<function>XFree</function>
-with the returned pointer.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the display associated with an input method, use
-<function>XDisplayOfIM</function>.
-<indexterm significance="preferred"><primary>XDisplayOfIM</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Display *<function>XDisplayOfIM</function></funcdef>
- <paramdef>XIM<parameter> im</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>im</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input method.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDisplayOfIM</function>
-function returns the display associated with the specified input method.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To get the locale associated with an input method, use
-<function>XLocaleOfIM</function>.
-<indexterm significance="preferred"><primary>XLocaleOfIM</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XLocaleOfIM</function></funcdef>
- <paramdef>XIM<parameter> im</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>im</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input method.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XLocaleOfIM</function>
-function returns the locale associated with the specified input method.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To register an input method instantiate callback, use
-<function>XRegisterIMInstantiateCallback</function>.
-<indexterm significance="preferred"><primary>XRegisterIMInstantiateCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XRegisterIMInstantiateCallback</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XrmDatabase<parameter> db</parameter></paramdef>
- <paramdef>char<parameter> *res_name</parameter></paramdef>
- <paramdef>char<parameter> *res_class</parameter></paramdef>
- <paramdef>XIMProc<parameter> callback</parameter></paramdef>
- <paramdef>XPointer<parameter> *client_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>db</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a pointer to the resource database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>res_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the full resource name of the application.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>res_class</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the full class name of the application.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>callback</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a pointer to the input method instantiate callback.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XRegisterIMInstantiateCallback</function>
-function registers a callback to be invoked whenever a new input method
-becomes available for the specified display that matches the current
-locale and modifiers.
-</para>
-<para>
-<!-- .LP -->
-The function returns
-<symbol>True</symbol>
- if it succeeds; otherwise, it returns
-<symbol>False</symbol>.
-</para>
-<para>
-<!-- .LP -->
-The generic prototype is as follows:
-<indexterm significance="preferred"><primary>IMInstantiateCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>IMInstantiateCallback</replaceable></function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XPointer<parameter> call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Not used for this callback and always passed as NULL.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-To unregister an input method instantiation callback, use
-<function>XUnregisterIMInstantiateCallback</function>.
-<indexterm significance="preferred"><primary>XUnregisterIMInstantiateCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XUnregisterIMInstantiateCallback</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XrmDatabase<parameter> db</parameter></paramdef>
- <paramdef>char<parameter> *res_name</parameter></paramdef>
- <paramdef>char<parameter> *res_class</parameter></paramdef>
- <paramdef>XIMProc<parameter> callback</parameter></paramdef>
- <paramdef>XPointer<parameter> *client_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>db</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a pointer to the resource database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>res_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the full resource name of the application.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>res_class</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the full class name of the application.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>callback</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a pointer to the input method instantiate callback.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUnregisterIMInstantiateCallback</function>
-function removes an input method instantiation callback previously
-registered.
-The function returns
-<symbol>True</symbol>
-if it succeeds; otherwise, it returns
-<symbol>False</symbol>.
-</para>
-</sect2>
-<sect2 id="Input_Method_Values">
-<title>Input Method Values</title>
-<!-- .XS -->
-<!-- (SN Input Method Values -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The following table describes how <acronym>XIM</acronym> values are interpreted
-by an input method.
-The first column lists the <acronym>XIM</acronym> values.
-The second column indicates how each of the <acronym>XIM</acronym> values
-are treated by that input style.
-</para>
-<para>
-<!-- .LP -->
-</para>
-<para>
-<!-- .LP -->
-The following keys apply to this table.
-</para>
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <thead>
- <row>
- <entry>Key</entry>
- <entry>Explanation</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry>D</entry>
- <entry>This value may be set using
- <function>XSetIMValues</function>.
- If it is not set,
- a default is provided.</entry>
- </row>
- <row>
- <entry>S</entry>
- <entry>This value may be set using <function>XSetIMValues</function>.</entry>
- </row>
- <row>
- <entry>G</entry>
- <entry>This value may be read using <function>XGetIMValues</function>.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<!-- .LP -->
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <thead>
- <row>
- <entry><acronym>XIM</acronym> Value</entry>
- <entry>Key</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry><symbol>XNQueryInputStyle</symbol></entry>
- <entry>G</entry>
- </row>
- <row>
- <entry><symbol>XNResourceName</symbol></entry>
- <entry>D-S-G</entry>
- </row>
- <row>
- <entry><symbol>XNResourceClass</symbol></entry>
- <entry>D-S-G</entry>
- </row>
- <row>
- <entry><symbol>XNDestroyCallback</symbol></entry>
- <entry>D-S-G</entry>
- </row>
- <row>
- <entry><symbol>XNQueryIMValuesList</symbol></entry>
- <entry>G</entry>
- </row>
- <row>
- <entry><symbol>XNQueryICValuesList</symbol></entry>
- <entry>G</entry>
- </row>
- <row>
- <entry><symbol>XNVisiblePosition</symbol></entry>
- <entry>G</entry>
- </row>
- <row>
- <entry><symbol>XNR6PreeditCallback</symbol></entry>
- <entry>D-S-G</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-<symbol>XNR6PreeditCallback</symbol>
-is obsolete and its use is not recommended (see section 13.5.4.6).
-</para>
-
-<sect3 id="Query_Input_Style">
-<title>Query Input Style</title>
-<!-- .XS -->
-<!-- (SN Query Input Style -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-A client should always query the input method to determine which input
-styles are supported.
-The client should then find an input style it is capable of supporting.
-</para>
-<para>
-<!-- .LP -->
-If the client cannot find an input style that it can support,
-it should negotiate with the user the continuation of the program
-(exit, choose another input method, and so on).
-</para>
-<para>
-<!-- .LP -->
-The argument value must be a pointer to a location
-where the returned value will be stored.
-The returned value is a pointer to a structure of type
-<structname>XIMStyles</structname>.
-Clients are responsible for freeing the
-<structname>XIMStyles</structname>
-structure.
-To do so, use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XIMStyles</structname>
-structure is defined as follows:
-</para>
-
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XIMStyle</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPreeditArea</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPreeditCallbacks</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPreeditPosition</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPreeditNothing</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPreeditNone</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMStatusArea</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMStatusCallbacks</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMStatusNothing</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMStatusNone</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMStyles</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-typedef unsigned long XIMStyle;
-
-
-#define XIMPreeditArea 0x0001L
-#define XIMPreeditCallbacks 0x0002L
-#define XIMPreeditPosition 0x0004L
-#define XIMPreeditNothing 0x0008L
-#define XIMPreeditNone 0x0010L
-
-#define XIMStatusArea 0x0100L
-#define XIMStatusCallbacks 0x0200L
-#define XIMStatusNothing 0x0400L
-#define XIMStatusNone 0x0800L
-
-typedef struct {
- unsigned short count_styles;
- XIMStyle * supported_styles;
-} XIMStyles;
-
-</literallayout>
-
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-An
-<structname>XIMStyles</structname>
-structure contains the number of input styles supported
-in its count_styles field.
-This is also the size of the supported_styles array.
-</para>
-<para>
-<!-- .LP -->
-The supported styles is a list of bitmask combinations,
-which indicate the combination of styles for each of the areas supported.
-These areas are described later.
-Each element in the list should select one of the bitmask values for
-each area.
-The list describes the complete set of combinations supported.
-Only these combinations are supported by the input method.
-</para>
-<para>
-<!-- .LP -->
-The preedit category defines what type of support is provided
-by the input method for preedit information.
-</para>
-<indexterm significance="preferred"><primary>XIMPreeditArea</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPreeditPosition</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPreeditCallbacks</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPreeditNothing</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPreeditNone</primary></indexterm>
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <tbody>
- <row>
- <entry><symbol>XIMPreeditArea</symbol></entry>
- <entry>If chosen,
- the input method would require the client to provide some area values
- for it to do its preediting.
- Refer to <acronym>XIC</acronym> values
- <symbol>XNArea</symbol>
- and
- <symbol>XNAreaNeeded</symbol>.</entry>
- </row>
- <row>
- <entry><symbol>XIMPreeditPosition</symbol></entry>
- <entry>If chosen,
- the input method would require the client to provide positional values.
- Refer to <acronym>XIC</acronym> values
- <symbol>XNSpotLocation</symbol>
- and
- <symbol>XNFocusWindow</symbol>.</entry>
- </row>
- <row>
- <entry><symbol>XIMPreeditCallbacks</symbol></entry>
- <entry>If chosen,
- the input method would require the client to define the set of preedit callbacks.
- Refer to <acronym>XIC</acronym> values
- <symbol>XNPreeditStartCallback</symbol>,
- <symbol>XNPreeditDoneCallback</symbol>,
- <symbol>XNPreeditDrawCallback</symbol>,
- and
- <symbol>XNPreeditCaretCallback</symbol>.</entry>
- </row>
- <row>
- <entry><symbol>XIMPreeditNothing</symbol></entry>
- <entry>If chosen, the input method can function without any preedit values.</entry>
- </row>
- <row>
- <entry><symbol>XIMPreeditNone</symbol></entry>
- <entry>The input method does not provide any preedit feedback.
- Any preedit value is ignored.
- This style is mutually exclusive with the other preedit styles.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-The status category defines what type of support is provided
-by the input method for status information.
-</para>
-<indexterm significance="preferred"><primary>XIMStatusArea</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMStatusCallbacks</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMStatusNothing</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMStatusNone</primary></indexterm>
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <tbody>
- <row>
- <entry><symbol>XIMStatusArea</symbol></entry>
- <entry>The input method requires the client to provide
- some area values for it to do its status feedback.
- See
- <symbol>XNArea</symbol>
- and
- <symbol>XNAreaNeeded</symbol>.</entry>
- </row>
- <row>
- <entry><symbol>XIMStatusCallbacks</symbol></entry>
- <entry>The input method requires the client to define the set of status callbacks,
- <symbol>XNStatusStartCallback</symbol>,
- <symbol>XNStatusDoneCallback</symbol>,
- and
- <symbol>XNStatusDrawCallback</symbol>.</entry>
- </row>
- <row>
- <entry><symbol>XIMStatusNothing</symbol></entry>
- <entry>The input method can function without any status values.</entry>
- </row>
- <row>
- <entry><symbol>XIMStatusNone</symbol></entry>
- <entry>The input method does not provide any status feedback.
- If chosen, any status value is ignored.
- This style is mutually exclusive with the other status styles.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-</sect3>
-<sect3 id="Resource_Name_and_Class_c">
-<title>Resource Name and Class</title>
-<!-- .XS -->
-<!-- (SN Resource Name and Class -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNResourceName</symbol>
-and
-<symbol>XNResourceClass</symbol>
-arguments are strings that specify the full name and class
-used by the input method.
-These values should be used as prefixes for the name and class
-when looking up resources that may vary according to the input method.
-If these values are not set,
-the resources will not be fully specified.
-</para>
-<para>
-<!-- .LP -->
-It is not intended that values that can be set as <acronym>XIM</acronym> values be
-set as resources.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-<sect3 id="Destroy_Callback">
-<title>Destroy Callback</title>
-<!-- .XS -->
-<!-- (SN Destroy Callback -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNDestroyCallback</symbol>
-argument is a pointer to a structure of type
-<structname>XIMCallback</structname>.
-<symbol>XNDestroyCallback</symbol>
-is triggered when an input method stops its service for any reason.
-After the callback is invoked, the input method is closed and the
-associated input context(s) are destroyed by Xlib.
-Therefore, the client should not call
-<function>XCloseIM</function>
-or
-<function>XDestroyIC</function>.
-</para>
-<para>
-<!-- .LP -->
-The generic prototype of this callback function is as follows:
-<indexterm significance="preferred"><primary>DestroyCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>DestroyCallback</replaceable></function></funcdef>
- <paramdef>XIM<parameter> im</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XPointer<parameter> call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>im</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input method.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Not used for this callback and always passed as NULL.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-A DestroyCallback is always called with a NULL call_data argument.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-<sect3 id="Query_IM_IC_Values_List">
-<title>Query IM/IC Values List</title>
-<!-- .XS -->
-<!-- (SN Query IM/IC Values List -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<symbol>XNQueryIMValuesList</symbol>
-and
-<symbol>XNQueryICValuesList</symbol>
-are used to query about <acronym>XIM</acronym> and <acronym>XIC</acronym> values supported by the input method.
-</para>
-<para>
-<!-- .LP -->
-The argument value must be a pointer to a location where the returned
-value will be stored. The returned value is a pointer to a structure
-of type
-<structname>XIMValuesList</structname>.
-Clients are responsible for freeing the
-<structname>XIMValuesList</structname>
-structure.
-To do so, use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XIMValuesList</structname>
-structure is defined as follows:
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- unsigned short count_values;
- char **supported_values;
-} XIMValuesList;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-</para>
-</sect3>
-<sect3 id="Visible_Position">
-<title>Visible Position</title>
-<!-- .XS -->
-<!-- (SN Visible Position -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNVisiblePosition</symbol>
-argument indicates whether the visible position masks of
-<type>XIMFeedback</type>
-in
-<structname>XIMText</structname>
-are available.
-</para>
-<para>
-<!-- .LP -->
-The argument value must be a pointer to a location where the returned
-value will be stored. The returned value is of type
-<type>Bool</type>.
-If the returned value is
-<symbol>True</symbol>,
-the input method uses the visible position masks of
-<type>XIMFeedback</type>
-in
-<structname>XIMText</structname>;
-otherwise, the input method does not use the masks.
-</para>
-<para>
-<!-- .LP -->
-Because this <acronym>XIM</acronym> value is optional, a client should call
-<function>XGetIMValues</function>
-with argument
-<symbol>XNQueryIMValuesList</symbol>
-before using this argument.
-If the
-<symbol>XNVisiblePosition</symbol>
-does not exist in the IM values list returned from
-<symbol>XNQueryIMValuesList</symbol>,
-the visible position masks of
-<type>XIMFeedback</type>
-in
-<structname>XIMText</structname>
-are not used to indicate the visible position.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-<sect3 id="Preedit_Callback_Behavior">
-<title>Preedit Callback Behavior</title>
-<!-- .XS -->
-<!-- (SN Preedit Callback Behavior -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNR6PreeditCallback</symbol>
-argument originally included in the X11R6 specification has been
-deprecated.\(dg
-<!-- .\" If XNR6PreeditCallbackBehavior is not deprecated, then its type -->
-<!-- .\" should be changed from *Bool to Bool. -->
-<!-- .FS \(dg -->
-During formulation of the X11R6 specification, the behavior of
-the R6 PreeditDrawCallbacks was going to differ significantly from
-that of the R5 callbacks.
-Late changes to the specification converged the R5 and R6 behaviors,
-eliminating the need for
-<symbol>XNR6PreeditCallback</symbol>.
-Unfortunately, this argument was not removed from the R6 specification
-before it was published.
-<!-- .FE -->
-</para>
-<para>
-<!-- .LP -->
-The
-<symbol>XNR6PreeditCallback</symbol>
-argument indicates whether the behavior of preedit callbacks regarding
-<structname>XIMPreeditDrawCallbackStruct</structname>
-values follows Release 5 or Release 6 semantics.
-</para>
-<para>
-<!-- .LP -->
-The value is of type
-<type>Bool</type>.
-When querying for
-<symbol>XNR6PreeditCallback</symbol>,
-if the returned value is
-<symbol>True</symbol>,
-the input method uses the Release 6 behavior;
-otherwise, it uses the Release 5 behavior.
-The default value is
-<symbol>False</symbol>.
-In order to use Release 6 semantics, the value of
-<symbol>XNR6PreeditCallback</symbol>
-must be set to
-<symbol>True</symbol>.
-</para>
-<para>
-<!-- .LP -->
-Because this <acronym>XIM</acronym> value is optional, a client should call
-<function>XGetIMValues</function>
-with argument
-<symbol>XNQueryIMValuesList</symbol>
-before using this argument.
-If the
-<symbol>XNR6PreeditCallback</symbol>
-does not exist in the IM values list returned from
-<symbol>XNQueryIMValuesList</symbol>,
-the PreeditCallback behavior is Release 5 semantics.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-</sect2>
-<sect2 id="Input_Context_Functions">
-<title>Input Context Functions</title>
-<!-- .XS -->
-<!-- (SN Input Context Functions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-An input context is an abstraction that is used to contain both the data
-required (if any) by an input method and the information required
-to display that data.
-There may be multiple input contexts for one input method.
-The programming interfaces for creating, reading, or modifying
-an input context use a variable argument list.
-The name elements of the argument lists are referred to as <acronym>XIC</acronym> values.
-It is intended that input methods be controlled by these <acronym>XIC</acronym> values.
-As new <acronym>XIC</acronym> values are created,
-they should be registered with the X Consortium.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create an input context, use
-<function>XCreateIC</function>.
-<indexterm significance="preferred"><primary>XCreateIC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XIC <function>XCreateIC</function></funcdef>
- <paramdef>XIM<parameter> im</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>im</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input method.
-<!-- .ds Al \ to set <acronym>XIC</acronym> values -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- ...
- </term>
- <listitem>
- <para>
-Specifies the variable length argument list(Al.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreateIC</function>
-function creates a context within the specified input method.
-</para>
-<para>
-<!-- .LP -->
-Some of the arguments are mandatory at creation time, and
-the input context will not be created if those arguments are not provided.
-The mandatory arguments are the input style and the set of text callbacks
-(if the input style selected requires callbacks).
-All other input context values can be set later.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreateIC</function>
-returns a NULL value if no input context could be created.
-A NULL value could be returned for any of the following reasons:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-A required argument was not set.
- </para>
- </listitem>
- <listitem>
- <para>
-A read-only argument was set (for example,
-<symbol>XNFilterEvents</symbol>).
- </para>
- </listitem>
- <listitem>
- <para>
-The argument name is not recognized.
- </para>
- </listitem>
- <listitem>
- <para>
-The input method encountered an input method implementation-dependent error.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-<function>XCreateIC</function>
-can generate
-<errorname>BadAtom</errorname>,
-<errorname>BadColor</errorname>,
-<errorname>BadPixmap</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To destroy an input context, use
-<function>XDestroyIC</function>.
-<indexterm significance="preferred"><primary>XDestroyIC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XDestroyIC</function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<function>XDestroyIC</function>
-destroys the specified input context.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To communicate to and synchronize with input method
-for any changes in keyboard focus from the client side,
-use
-<function>XSetICFocus</function>
-and
-<function>XUnsetICFocus</function>.
-<indexterm significance="preferred"><primary>XSetICFocus</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XSetICFocus</function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetICFocus</function>
-function allows a client to notify an input method that the focus window
-attached to the specified input context has received keyboard focus.
-The input method should take action to provide appropriate feedback.
-Complete feedback specification is a matter of user interface policy.
-</para>
-<para>
-<!-- .LP -->
-Calling
-<function>XSetICFocus</function>
-does not affect the focus window value.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-<indexterm significance="preferred"><primary>XUnsetICFocus</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XUnsetICFocus</function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUnsetICFocus</function>
-function allows a client to notify an input method that the specified input context
-has lost the keyboard focus and that no more input is expected on the focus window
-attached to that input context.
-The input method should take action to provide appropriate feedback.
-Complete feedback specification is a matter of user interface policy.
-</para>
-<para>
-<!-- .LP -->
-Calling
-<function>XUnsetICFocus</function>
-does not affect the focus window value;
-the client may still receive
-events from the input method that are directed to the focus window.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To reset the state of an input context to its initial state, use
-<function>XmbResetIC</function>
-or
-<function>XwcResetIC</function>.
-<indexterm significance="preferred"><primary>XmbResetIC</primary></indexterm>
-<indexterm significance="preferred"><primary>XwcResetIC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XmbResetIC</function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>wchar_t *<function>XwcResetIC</function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-When
-<symbol>XNResetState</symbol>
-is set to
-<symbol>XIMInitialState</symbol>,
-<function>XmbResetIC</function>
-and
-<function>XwcResetIC</function>
-reset an input context to its initial state;
-when
-<symbol>XNResetState</symbol>
-is set to
-<symbol>XIMPreserveState</symbol>,
-the current input context state is preserved.
-In both cases, any input pending on that context is deleted.
-The input method is required to clear the preedit area, if any,
-and update the status accordingly.
-Calling
-<function>XmbResetIC</function>
-or
-<function>XwcResetIC</function>
-does not change the focus.
-</para>
-<para>
-<!-- .LP -->
-The return value of
-<function>XmbResetIC</function>
-is its current preedit string as a multibyte string.
-If there is any preedit text drawn or visible to the user,
-then these procedures must return a non-NULL string.
-If there is no visible preedit text,
-then it is input method implementation-dependent
-whether these procedures return a non-NULL string or NULL.
-</para>
-<para>
-<!-- .LP -->
-The client should free the returned string by calling
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To get the input method associated with an input context, use
-<function>XIMOfIC</function>.
-<indexterm significance="preferred"><primary>XIMOfIC</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XIM <function>XIMOfIC</function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XIMOfIC</function>
-function returns the input method associated with the specified input context.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-Xlib provides two functions for setting and reading <acronym>XIC</acronym> values, respectively,
-<function>XSetICValues</function>
-and
-<function>XGetICValues</function>.
-Both functions have a variable-length argument list.
-In that argument list, any <acronym>XIC</acronym> value's name must be denoted
-with a character string using the X Portable Character Set.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set <acronym>XIC</acronym> values, use
-<function>XSetICValues</function>.
-<indexterm significance="preferred"><primary>XSetICValues</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XSetICValues</function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
-<!-- .ds Al \ to set <acronym>XIC</acronym> values -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- ...
- </term>
- <listitem>
- <para>
-Specifies the variable length argument list(Al.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetICValues</function>
-function returns NULL if no error occurred;
-otherwise,
-it returns the name of the first argument that could not be set.
-An argument might not be set for any of the following reasons:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The argument is read-only (for example,
-<symbol>XNFilterEvents</symbol>).
- </para>
- </listitem>
- <listitem>
- <para>
-The argument name is not recognized.
- </para>
- </listitem>
- <listitem>
- <para>
-An implementation-dependent error occurs.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Each value to be set must be an appropriate datum,
-matching the data type imposed by the semantics of the argument.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetICValues</function>
-can generate
-<errorname>BadAtom</errorname>,
-<errorname>BadColor</errorname>,
-<errorname>BadCursor</errorname>,
-<errorname>BadPixmap</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain <acronym>XIC</acronym> values, use
-<function>XGetICValues</function>.
-<indexterm significance="preferred"><primary>XGetICValues</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XGetICValues</function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
-<!-- .ds Al \ to get XIC values -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- ...
- </term>
- <listitem>
- <para>
-Specifies the variable length argument list(Al.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetICValues</function>
-function returns NULL if no error occurred; otherwise,
-it returns the name of the first argument that could not be obtained.
-An argument could not be obtained for any of the following reasons:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The argument name is not recognized.
- </para>
- </listitem>
- <listitem>
- <para>
-The input method encountered an implementation-dependent error.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-Each IC attribute value argument (following a name) must point to
-a location where the IC value is to be stored.
-That is, if the IC value is of type T,
-the argument must be of type T*.
-If T itself is a pointer type,
-then
-<function>XGetICValues</function>
-allocates memory to store the actual data,
-and the client is responsible for freeing this data by calling
-<function>XFree</function>
-with the returned pointer.
-The exception to this rule is for an IC value of type
-<type>XVaNestedList</type>
-(for preedit and status attributes).
-In this case, the argument must also be of type
-<type>XVaNestedList</type>.
-Then, the rule of changing type T to T* and freeing the allocated data
-applies to each element of the nested list.
-</para>
-</sect2>
-<sect2 id="Input_Context_Values">
-<title>Input Context Values</title>
-<!-- .XS -->
-<!-- (SN Input Context Values -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The following tables describe how <acronym>XIC</acronym> values are interpreted
-by an input method depending on the input style chosen by the
-user.
-</para>
-<para>
-<!-- .LP -->
-The first column lists the <acronym>XIC</acronym> values.
-The second column indicates which values are involved in affecting,
-negotiating, and setting the geometry of the input method windows.
-The subentries under the third column indicate the different
-input styles that are supported.
-Each of these columns indicates how each of the <acronym>XIC</acronym> values
-are treated by that input style.
-</para>
-<para>
-<!-- .LP -->
-The following keys apply to these tables.
-</para>
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <thead>
- <row>
- <entry>Key</entry>
- <entry>Explanation</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry>C</entry>
- <entry>This value must be set with <function>XCreateIC</function>.</entry>
- </row>
- <row>
- <entry>D</entry>
- <entry>This value may be set using
- <function>XCreateIC</function>.>
- If it is not set,>
- a default is provided.</entry>
- </row>
- <row>
- <entry>G</entry>
- <entry>This value may be read using
- <function>XGetICValues</function>.</entry>
- </row>
- <row>
- <entry>GN</entry>
- <entry>This value may cause geometry negotiation when its value is set by means of
- <function>XCreateIC</function>
- or
- <function>XSetICValues</function>.</entry>
- </row>
- <row>
- <entry>GR</entry>
- <entry>This value will be the response of the input method when any
- GN value is changed.</entry>
- </row>
- <row>
- <entry>GS</entry>
- <entry>This value will cause the geometry of the input method window to be set.</entry>
- </row>
- <row>
- <entry>O</entry>
- <entry>This value must be set once and only once.
- It need not be set at create time.</entry>
- </row>
- <row>
- <entry>S</entry>
- <entry>This value may be set with
- <function>XSetICValues</function>.</entry>
- </row>
- <row>
- <entry>Ignored</entry>
- <entry>This value is ignored by the input method for the given input style.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<!-- .LP -->
-<informaltable>
- <tgroup cols='7' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <colspec colname='c4'/>
- <colspec colname='c5'/>
- <colspec colname='c6'/>
- <colspec colname='c7'/>
- <tbody>
- <row>
- <entry><acronym>XIC</acronym> Value</entry>
- <entry>Geometry Mangement</entry>
- <entry>Preedit Callback</entry>
- <entry>Preedit Position</entry>
- <entry>Input Style Preedit Area</entry>
- <entry>Preedit Nothing</entry>
- <entry>Preedit None</entry>
- </row>
- <row>
- <entry>Input Style</entry>
- <entry></entry>
- <entry>C-G</entry>
- <entry>C-G</entry>
- <entry>C-G</entry>
- <entry>C-G</entry>
- <entry>C-G</entry>
- </row>
- <row>
- <entry>Client Window</entry>
- <entry></entry>
- <entry>O-G</entry>
- <entry>O-G</entry>
- <entry>O-G</entry>
- <entry>O-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Focus Window</entry>
- <entry>GN</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Resource Name</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Resource Class</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Geometry Callback</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Filter Events</entry>
- <entry></entry>
- <entry>G</entry>
- <entry>G</entry>
- <entry>G</entry>
- <entry>G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Destroy Callback</entry>
- <entry></entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- </row>
- <row>
- <entry>String Conversion Callback</entry>
- <entry></entry>
- <entry>S-G</entry>
- <entry>S-G</entry>
- <entry>S-G</entry>
- <entry>S-G</entry>
- <entry>S-G</entry>
- </row>
- <row>
- <entry>String Conversion</entry>
- <entry></entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- </row>
- <row>
- <entry>Reset State</entry>
- <entry></entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>HotKey</entry>
- <entry></entry>
- <entry>S-G</entry>
- <entry>S-G</entry>
- <entry>S-G</entry>
- <entry>S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>HotKeyState</entry>
- <entry></entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry><function>Preedit</function></entry>
- </row>
- <row>
- <entry>Area</entry>
- <entry>GS</entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Area Needed</entry>
- <entry>GN-GR</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- <entry>S-G</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Spot Location</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Colormap</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Foreground</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Background</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Background Pixmap</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Font Set</entry>
- <entry>GN</entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Line Spacing</entry>
- <entry>GN</entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Cursor</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Preedit State</entry>
- <entry></entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Preedit State Notify Callback</entry>
- <entry></entry>
- <entry>S-G</entry>
- <entry>S-G</entry>
- <entry>S-G</entry>
- <entry>S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Preedit Callbacks</entry>
- <entry></entry>
- <entry>C-S-G</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<!-- .LP -->
-<informaltable>
- <tgroup cols='6' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <colspec colname='c4'/>
- <colspec colname='c5'/>
- <colspec colname='c6'/>
- <thead>
- <row>
- <entry><acronym>XIC</acronym> Value</entry>
- <entry>Geomentry Management</entry>
- <entry>Status Callback</entry>
- <entry>Status Area</entry>
- <entry>Status Nothing</entry>
- <entry>Status None</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry>Input Style</entry>
- <entry></entry>
- <entry>C-G</entry>
- <entry>C-G</entry>
- <entry>C-G</entry>
- <entry>C-G</entry>
- </row>
- <row>
- <entry>Client Window</entry>
- <entry></entry>
- <entry>O-G</entry>
- <entry>O-G</entry>
- <entry>O-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Focus Window</entry>
- <entry>GN</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Resource Name</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Resource Class</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Geometry Callback</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Filter Events</entry>
- <entry></entry>
- <entry>G</entry>
- <entry>G</entry>
- <entry>G</entry>
- <entry>G</entry>
- </row>
- <row>
- <entry><type>Status</type></entry>
- </row>
- <row>
- <entry>Area</entry>
- <entry>GS</entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Area Needed</entry>
- <entry>GN-GR</entry>
- <entry>Ignored</entry>
- <entry>S-G</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Colormap</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Foreground</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Background</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Background Pixmap</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Font Set</entry>
- <entry>GN</entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Line Spacing</entry>
- <entry>GN</entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Cursor</entry>
- <entry></entry>
- <entry>Ignored</entry>
- <entry>D-S-G</entry>
- <entry>D-S-G</entry>
- <entry>Ignored</entry>
- </row>
- <row>
- <entry>Status Callbacks</entry>
- <entry></entry>
- <entry>C-S-G</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- <entry>Ignored</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-<sect3 id="Input_Style">
-<title>Input Style</title>
-<!-- .XS -->
-<!-- (SN Input Style -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNInputStyle</symbol>
-argument specifies the input style to be used.
-The value of this argument must be one of the values returned by the
-<function>XGetIMValues</function>
-function with the
-<symbol>XNQueryInputStyle</symbol>
-argument specified in the supported_styles list.
-</para>
-<para>
-<!-- .LP -->
-Note that this argument must be set at creation time
-and cannot be changed.
-</para>
-</sect3>
-<sect3 id="Client_Window">
-<title>Client Window</title>
-<!-- .XS -->
-<!-- (SN Client Window -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNClientWindow</primary></indexterm>
-The
-<symbol>XNClientWindow</symbol>
-argument specifies to the input method the client window in
-which the input method
-can display data or create subwindows.
-Geometry values for input method areas are given with respect to the client
-window.
-Dynamic change of client window is not supported.
-This argument may be set only once and
-should be set before any input is done using this input context.
-If it is not set,
-the input method may not operate correctly.
-</para>
-<para>
-<!-- .LP -->
-If an attempt is made to set this value a second time with
-<function>XSetICValues</function>,
-the string
-<symbol>XNClientWindow</symbol>
-will be returned by
-<function>XSetICValues</function>,
-and the client window will not be changed.
-</para>
-<para>
-<!-- .LP -->
-If the client window is not a valid window ID on the display
-attached to the input method,
-a
-<errorname>BadWindow</errorname>
-error can be generated when this value is used by the input method.
-</para>
-</sect3>
-<sect3 id="Focus_Window">
-<title>Focus Window</title>
-<!-- .XS -->
-<!-- (SN Focus Window -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNFocusWindow</primary></indexterm>
-The
-<symbol>XNFocusWindow</symbol>
-argument specifies the focus window.
-The primary purpose of the
-<symbol>XNFocusWindow</symbol>
-is to identify the window that will receive the key event when input
-is composed.
-In addition, the input method may possibly affect the focus window
-as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Select events on it
- </para>
- </listitem>
- <listitem>
- <para>
-Send events to it
- </para>
- </listitem>
- <listitem>
- <para>
-Modify its properties
- </para>
- </listitem>
- <listitem>
- <para>
-Grab the keyboard within that window
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The associated value must be of type
-<type>Window</type>.
-If the focus window is not a valid window ID on the display
-attached to the input method,
-a
-<errorname>BadWindow</errorname>
-error can be generated when this value is used by the input method.
-</para>
-<para>
-<!-- .LP -->
-When this <acronym>XIC</acronym> value is left unspecified,
-the input method will use the client window as the default focus window.
-</para>
-</sect3>
-<sect3 id="Resource_Name_and_Class_b">
-<title>Resource Name and Class</title>
-<!-- .XS -->
-<!-- (SN Resource Name and Class -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNResourceName</primary></indexterm>
-<indexterm significance="preferred"><primary>XNResourceClass</primary></indexterm>
-The
-<symbol>XNResourceName</symbol>
-and
-<symbol>XNResourceClass</symbol>
-arguments are strings that specify the full name and class
-used by the client to obtain resources for the client window.
-These values should be used as prefixes for name and class
-when looking up resources that may vary according to the input context.
-If these values are not set,
-the resources will not be fully specified.
-</para>
-<para>
-<!-- .LP -->
-It is not intended that values that can be set as <acronym>XIC</acronym> values be
-set as resources.
-</para>
-</sect3>
-<sect3 id="Geometry_Callback">
-<title>Geometry Callback</title>
-<!-- .XS -->
-<!-- (SN Geometry Callback -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNGeometryCallback</primary></indexterm>
-The
-<symbol>XNGeometryCallback</symbol>
-argument is a structure of type
-<structname>XIMCallback</structname>
-(see section 13.5.6.13.12).
-</para>
-<para>
-<!-- .LP -->
-The
-<symbol>XNGeometryCallback</symbol>
-argument specifies the geometry callback that a client can set.
-This callback is not required for correct operation of either
-an input method or a client.
-It can be set for a client whose user interface policy permits
-an input method to request the dynamic change of that input
-method's window.
-An input method that does dynamic change will need to filter any
-events that it uses to initiate the change.
-</para>
-</sect3>
-<sect3 id="Filter_Events">
-<title>Filter Events</title>
-<!-- .XS -->
-<!-- (SN Filter Events -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNFilterEvents</primary></indexterm>
-The
-<symbol>XNFilterEvents</symbol>
-argument returns the event mask that an input method needs
-to have selected for.
-The client is expected to augment its own event mask
-for the client window with this one.
-</para>
-<para>
-<!-- .LP -->
-This argument is read-only, is set by the input method at create time,
-and is never changed.
-</para>
-<para>
-<!-- .LP -->
-The type of this argument is
-<type>unsigned</type>
-<type>long</type>.
-Setting this value will cause an error.
-</para>
-</sect3>
-<sect3 id="Destroy_Callback_b">
-<title>Destroy Callback</title>
-<!-- .XS -->
-<!-- (SN Destroy Callback -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNDestroyCallback</symbol>
-argument is a pointer to a structure of type
-<structname>XIMCallback</structname>
-(see section 13.5.6.13.12). This callback is triggered when the input method
-stops its service for any reason; for example, when a connection to an IM
-server is broken. After the destroy callback is called,
-the input context is destroyed and the input method is closed.
-Therefore, the client should not call
-<function>XDestroyIC</function>
-and
-<function>XCloseIM</function>.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-<sect3 id="String_Conversion_Callback">
-<title>String Conversion Callback</title>
-<!-- .XS -->
-<!-- (SN String Conversion Callback -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNStringConversionCallback</symbol>
-argument is a structure of type
-<structname>XIMCallback</structname>
-(see section 13.5.6.13.12).
-</para>
-<para>
-<!-- .LP -->
-The
-<symbol>XNStringConversionCallback</symbol>
-argument specifies a string conversion callback. This callback
-is not required for correct operation of
-either the input method or the client. It can be set by a client
-to support string conversions that may be requested
-by the input method. An input method that does string conversions
-will filter any events that it uses to initiate the conversion.
-</para>
-<para>
-<!-- .LP -->
-Because this <acronym>XIC</acronym> value is optional, a client should call
-<function>XGetIMValues</function>
-with argument
-<symbol>XNQueryICValuesList</symbol>
-before using this argument.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-<sect3 id="String_Conversion_">
-<title>String Conversion </title>
-<!-- .XS -->
-<!-- (SN String Conversion -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNStringConversion</symbol>
-argument is a structure of type
-<structname>XIMStringConversionText</structname>.
-</para>
-<para>
-<!-- .LP -->
-The
-<symbol>XNStringConversion</symbol>
-argument specifies the string to be converted by an input method.
-This argument is not required for correct operation of either
-the input method or the client.
-</para>
-<para>
-<!-- .LP -->
-String conversion facilitates the manipulation of text independent
-of preediting.
-It is essential for some input methods and clients to manipulate
-text by performing context-sensitive conversion,
-reconversion, or transliteration conversion on it.
-</para>
-<para>
-<!-- .LP -->
-Because this <acronym>XIC</acronym> value is optional, a client should call
-<function>XGetIMValues</function>
-with argument
-<symbol>XNQueryICValuesList</symbol>
-before using this argument.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XIMStringConversionText</structname>
-structure is defined as follows:
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<literallayout class="monospaced">
-
-typedef struct _XIMStringConversionText {
- unsigned short length;
- XIMStringConversionFeedback *feedback;
- Bool encoding_is_wchar;
- union {
- char *mbs;
- wchar_t *wcs;
- } string;
-} XIMStringConversionText;
-
-typedef unsigned long XIMStringConversionFeedback;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The feedback member is reserved for future use. The text to be
-converted is defined by the string and length members. The length
-is indicated in characters. To prevent the library from freeing memory
-pointed to by an uninitialized pointer, the client should set the feedback
-element to NULL.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-<sect3 id="Reset_State">
-<title>Reset State</title>
-<!-- .XS -->
-<!-- (SN Reset State -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNResetState</symbol>
-argument specifies the state the input context will return to after calling
-<function>XmbResetIC</function>
-or
-<function>XwcResetIC</function>.
-</para>
-<para>
-<!-- .LP -->
-The <acronym>XIC</acronym> state may be set to its initial state, as specified by the
-<symbol>XNPreeditState</symbol>
-value when
-<function>XCreateIC</function>
-was called, or it may be set to preserve the current state.
-</para>
-<para>
-<!-- .LP -->
-The valid masks for
-<type>XIMResetState</type>
-are as follows:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XIMInitialState</primary></indexterm>
-<indexterm significance="preferred"><primary>XINPreserveState</primary></indexterm>
-<!-- .sM -->
-</para>
-<literallayout class="monospaced">
-typedef unsigned long XIMResetState;
-
-#define XIMInitialState (1L)
-#define XIMPreserveState (1L&lt;&lt;1)
-
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If
-<symbol>XIMInitialState</symbol>
-is set, then
-<function>XmbResetIC</function>
-and
-<function>XwcResetIC</function>
-will return to the initial
-<symbol>XNPreeditState</symbol>
-state of the <acronym>XIC</acronym>.
-</para>
-<para>
-<!-- .LP -->
-If
-<symbol>XIMPreserveState</symbol>
-is set, then
-<function>XmbResetIC</function>
-and
-<function>XwcResetIC</function>
-will preserve the current state of the <acronym>XIC</acronym>.
-</para>
-<para>
-<!-- .LP -->
-If
-<symbol>XNResetState</symbol>
-is left unspecified, the default is
-<symbol>XIMInitialState</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<type>XIMResetState</type>
-values other than those specified above will default to
-<symbol>XIMInitialState</symbol>.
-</para>
-<para>
-<!-- .LP -->
-Because this <acronym>XIC</acronym> value is optional, a client should call
-<function>XGetIMValues</function>
-with argument
-<symbol>XNQueryICValuesList</symbol>
-before using this argument.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-<sect3 id="Hot_Keys_b">
-<title>Hot Keys</title>
-<!-- .XS -->
-<!-- (SN Hot Keys -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNHotKey</symbol>
-argument specifies the hot key list to the <acronym>XIC</acronym>.
-The hot key list is a pointer to the structure of type
-<structname>XIMHotKeyTriggers</structname>,
-which specifies the key events that must be received
-without any interruption of the input method.
-For the hot key list set with this argument to be utilized, the client
-must also set
-<symbol>XNHotKeyState</symbol>
-to
-<symbol>XIMHotKeyStateON</symbol>.
-</para>
-<para>
-<!-- .LP -->
-Because this <acronym>XIC</acronym> value is optional, a client should call
-<function>XGetIMValues</function>
-with argument
-<symbol>XNQueryICValuesList</symbol>
-before using this functionality.
-</para>
-<para>
-<!-- .LP -->
-The value of the argument is a pointer to a structure of type
-<structname>XIMHotKeyTriggers</structname>.
-</para>
-<para>
-<!-- .LP -->
-If an event for a key in the hot key list is found, then the process will
-receive the event and it will be processed inside the client.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- KeySym keysym;
- unsigned int modifier;
- unsigned int modifier_mask;
-} XIMHotKeyTrigger;
-
-typedef struct {
- int num_hot_key;
- XIMHotKeyTrigger *key;
-} XIMHotKeyTriggers;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-</para>
-<para>
-<!-- .LP -->
-The combination of modifier and modifier_mask are used to represent one of
-three states for each modifier:
-either the modifier must be on, or the modifier must be off, or the modifier
-is a ``don't care'' - it may be on or off.
-When a modifier_mask bit is set to 0, the state of the associated modifier
-is ignored when evaluating whether the key is hot or not.
-</para>
-
-<informaltable>
- <tgroup cols='3' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <thead>
- <row>
- <entry>Modifier Bit</entry>
- <entry>Mask Bit</entry>
- <entry>Meaning</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry>0</entry>
- <entry>1</entry>
- <entry>The modifier must be off.</entry>
- </row>
- <row>
- <entry>1</entry>
- <entry>1</entry>
- <entry>The modifier must be on.</entry>
- </row>
- <row>
- <entry>n/a</entry>
- <entry>0</entry>
- <entry>Do not care if the modifier is on or off.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-</sect3>
-<sect3 id="Hot_Key_State">
-<title>Hot Key State</title>
-<!-- .XS -->
-<!-- (SN Hot Key State -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNHotKeyState</symbol>
-argument specifies the hot key state of the input method.
-This is usually used to switch the input method between hot key
-operation and normal input processing.
-</para>
-<para>
-<!-- .LP -->
-The value of the argument is a pointer to a structure of type
-XIMHotKeyState .
-</para>
-<literallayout class="monospaced">
-typedef unsigned long XIMHotKeyState;
-
-#define XIMHotKeyStateON (0x0001L)
-#define XIMHotKeyStateOFF (0x0002L)
-
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-</para>
-<para>
-<!-- .LP -->
-If not specified, the default is
-<symbol>XIMHotKeyStateOFF</symbol>.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-<sect3 id="Preedit_and_Status_Attributes">
-<title>Preedit and Status Attributes</title>
-<!-- .XS -->
-<!-- (SN Preedit and Status Attributes -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNPreeditAttributes</primary></indexterm>
-<indexterm significance="preferred"><primary>XNStatusAttributes</primary></indexterm>
-The
-<symbol>XNPreeditAttributes</symbol>
-and
-<symbol>XNStatusAttributes</symbol>
-arguments specify to an input method the attributes to be used for the
-preedit and status areas,
-if any.
-Those attributes are passed to
-<function>XSetICValues</function>
-or
-<function>XGetICValues</function>
-as a nested variable-length list.
-The names to be used in these lists are described in the following sections.
-</para>
-<sect4 id="Area">
-<title>Area</title>
-<!-- .XS -->
-<!-- (SN Area -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNArea</primary></indexterm>
-The value of the
-<symbol>XNArea</symbol>
-argument must be a pointer to a structure of type
-<structname>XRectangle</structname>.
-The interpretation of the
-<symbol>XNArea</symbol>
-argument is dependent on the input method style that has been set.
-</para>
-<para>
-<!-- .LP -->
-If the input method style is
-<symbol>XIMPreeditPosition</symbol>,
-<symbol>XNArea</symbol>
-specifies the clipping region within which preediting will take place.
-If the focus window has been set,
-the coordinates are assumed to be relative to the focus window.
-Otherwise, the coordinates are assumed to be relative to the client window.
-If neither has been set,
-the results are undefined.
-</para>
-<para>
-<!-- .LP -->
-If
-<symbol>XNArea</symbol>
-is not specified, is set to NULL, or is invalid,
-the input method will default the clipping region
-to the geometry of the
-<symbol>XNFocusWindow</symbol>.
-If the area specified is NULL or invalid,
-the results are undefined.
-</para>
-<para>
-<!-- .LP -->
-If the input style is
-<symbol>XIMPreeditArea</symbol>
-or
-<symbol>XIMStatusArea</symbol>,
-<symbol>XNArea</symbol>
-specifies the geometry provided by the client to the input method.
-The input method may use this area to display its data,
-either preedit or status depending on the area designated.
-The input method may create a window as a child of the client window
-with dimensions that fit the
-<symbol>XNArea</symbol>.
-The coordinates are relative to the client window.
-If the client window has not been set yet,
-the input method should save these values
-and apply them when the client window is set.
-If
-<symbol>XNArea</symbol>
-is not specified, is set to NULL, or is invalid,
-the results are undefined.
-</para>
-</sect4>
-<sect4 id="Area_Needed">
-<title>Area Needed</title>
-<!-- .XS -->
-<!-- (SN Area Needed -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNAreaNeeded</primary></indexterm>
-When set, the
-<symbol>XNAreaNeeded</symbol>
-argument specifies the geometry suggested by the client for this area
-(preedit or status).
-The value associated with the argument must be a pointer to a
-structure of type
-<structname>XRectangle</structname>.
-Note that the x, y values are not used
-and that nonzero values for width or height are the constraints
-that the client wishes the input method to respect.
-</para>
-<para>
-<!-- .LP -->
-When read, the
-<symbol>XNAreaNeeded</symbol>
-argument specifies the preferred geometry desired by the input method
-for the area.
-</para>
-<para>
-<!-- .LP -->
-This argument is only valid if the input style is
-<symbol>XIMPreeditArea</symbol>
-or
-<symbol>XIMStatusArea</symbol>.
-It is used for geometry negotiation between the client and the input method
-and has no other effect on the input method
-(see section 13.5.1.5).
-</para>
-</sect4>
-<sect4 id="Spot_Location">
-<title>Spot Location</title>
-<!-- .XS -->
-<!-- (SN Spot Location -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNSpotLocation</primary></indexterm>
-The
-<symbol>XNSpotLocation</symbol>
-argument specifies to the input method the coordinates of the spot
-to be used by an input method executing with
-<symbol>XNInputStyle</symbol>
-set to
-<symbol>XIMPreeditPosition</symbol>.
-When specified to any input method other than
-<symbol>XIMPreeditPosition</symbol>,
-this <acronym>XIC</acronym> value is ignored.
-</para>
-<para>
-<!-- .LP -->
-The x coordinate specifies the position where the next character
-would be inserted.
-The y coordinate is the position of the baseline used
-by the current text line in the focus window.
-The x and y coordinates are relative to the focus window, if it has been set;
-otherwise, they are relative to the client window.
-If neither the focus window nor the client window has been set,
-the results are undefined.
-</para>
-<para>
-<!-- .LP -->
-The value of the argument is a pointer to a structure of type
-<structname>XPoint</structname>.
-</para>
-</sect4>
-<sect4 id="Colormap">
-<title>Colormap</title>
-<!-- .XS -->
-<!-- (SN Colormap -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Two different arguments can be used to indicate what colormap the input method
-should use to allocate colors, a colormap ID, or a standard colormap name.
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNColormap</primary></indexterm>
-The
-<symbol>XNColormap</symbol>
-argument is used to specify a colormap ID.
-The argument value is of type
-<type>Colormap</type>.
-An invalid argument may generate a
-<errorname>BadColor</errorname>
-error when it is used by the input method.
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNStdColormap</primary></indexterm>
-The
-<symbol>XNStdColormap</symbol>
-argument is used to indicate the name of the standard colormap
-in which the input method should allocate colors.
-The argument value is an
-<type>Atom</type>
-that should be a valid atom for calling
-<function>XGetRGBColormaps</function>.
-An invalid argument may generate a
-<errorname>BadAtom</errorname>
-error when it is used by the input method.
-</para>
-<para>
-<!-- .LP -->
-If the colormap is left unspecified,
-the client window colormap becomes the default.
-</para>
-</sect4>
-<sect4 id="Foreground_and_Background">
-<title>Foreground and Background</title>
-<!-- .XS -->
-<!-- (SN Foreground and Background -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNForeground</primary></indexterm>
-<indexterm significance="preferred"><primary>XNBackground</primary></indexterm>
-The
-<symbol>XNForeground</symbol>
-and
-<symbol>XNBackground</symbol>
-arguments specify the foreground and background pixel, respectively.
-The argument value is of type
-<type>unsigned</type>
-<type>long</type>.
-It must be a valid pixel in the input method colormap.
-</para>
-<para>
-<!-- .LP -->
-If these values are left unspecified,
-the default is determined by the input method.
-</para>
-</sect4>
-<sect4 id="Background_Pixmap">
-<title>Background Pixmap</title>
-<!-- .XS -->
-<!-- (SN Background Pixmap -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNBackgroundPixmap</symbol>
-argument specifies a background pixmap to be used as the background of the
-window.
-The value must be of type
-<type>Pixmap</type>.
-An invalid argument may generate a
-<errorname>BadPixmap</errorname>
-error when it is used by the input method.
-</para>
-<para>
-<!-- .LP -->
-If this value is left unspecified,
-the default is determined by the input method.
-</para>
-</sect4>
-<sect4 id="Font_Set">
-<title>Font Set</title>
-<!-- .XS -->
-<!-- (SN Font Set -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNFontSet</primary></indexterm>
-The
-<symbol>XNFontSet</symbol>
-argument specifies to the input method what font set is to be used.
-The argument value is of type
-<type>XFontSet</type>.
-</para>
-<para>
-<!-- .LP -->
-If this value is left unspecified,
-the default is determined by the input method.
-</para>
-</sect4>
-<sect4 id="Line_Spacing">
-<title>Line Spacing</title>
-<!-- .XS -->
-<!-- (SN Line Spacing -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNLineSpace</symbol>
-argument specifies to the input method what line spacing is to be used
-in the preedit window if more than one line is to be used.
-This argument is of type
-<type>int</type>.
-</para>
-<para>
-<!-- .LP -->
-If this value is left unspecified,
-the default is determined by the input method.
-</para>
-</sect4>
-<sect4 id="Cursor">
-<title>Cursor</title>
-<!-- .XS -->
-<!-- (SN Cursor -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XNCursor</primary></indexterm>
-The
-<symbol>XNCursor</symbol>
-argument specifies to the input method what cursor is to be used
-in the specified window.
-This argument is of type
-<type>Cursor</type>.
-</para>
-<para>
-<!-- .LP -->
-An invalid argument may generate a
-<errorname>BadCursor</errorname>
-error when it is used by the input method.
-If this value is left unspecified,
-the default is determined by the input method.
-</para>
-</sect4>
-<sect4 id="Preedit_State">
-<title>Preedit State</title>
-<!-- .XS -->
-<!-- (SN Preedit State -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<symbol>XNPreeditState</symbol>
-argument specifies the state of input preediting for the input method.
-Input preediting can be on or off.
-</para>
-<para>
-<!-- .LP -->
-The valid mask names for
-<symbol>XNPreeditState</symbol>
-are as follows:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XIMPreeditUnknown</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPreeditEnable</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPreeditDisable</primary></indexterm>
-<!-- .sM -->
-</para>
-<!-- .LP -->
-<literallayout class="monospaced">
-typedef unsigned long XIMPreeditState;
-
-#define XIMPreeditUnknown 0L
-#define XIMPreeditEnable 1L
-#define XIMPreeditDisable (1L&lt;&lt;1)
-
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If a value of
-<symbol>XIMPreeditEnable</symbol>
-is set, then input preediting is turned on by the input method.
-</para>
-<para>
-<!-- .LP -->
-If a value of
-<symbol>XIMPreeditDisable</symbol>
-is set, then input preediting is turned off by the input method.
-</para>
-<para>
-<!-- .LP -->
-If
-<symbol>XNPreeditState</symbol>
-is left unspecified, then the state will be implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-When
-<symbol>XNResetState</symbol>
-is set to
-<symbol>XIMInitialState</symbol>,
-the
-<symbol>XNPreeditState</symbol>
-value specified at the creation time will be reflected as the initial state for
-<function>XmbResetIC</function>
-and
-<function>XwcResetIC</function>.
-</para>
-<para>
-<!-- .LP -->
-Because this <acronym>XIC</acronym> value is optional, a client should call
-<function>XGetIMValues</function>
-with argument
-<symbol>XNQueryICValuesList</symbol>
-before using this argument.
-</para>
-</sect4>
-<sect4 id="Preedit_State_Notify_Callback">
-<title>Preedit State Notify Callback</title>
-<!-- .XS -->
-<!-- (SN Preedit State Notify Callback -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The preedit state notify callback is triggered by the input method
-when the preediting state has changed.
-The value of the
-<symbol>XNPreeditStateNotifyCallback</symbol>
-argument is a pointer to a structure of type
-<structname>XIMCallback</structname>.
-The generic prototype is as follows:
-<indexterm significance="preferred"><primary>PreeditStateNotifyCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>PreeditStateNotifyCallback</replaceable></function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XIMPreeditStateNotifyCallbackStruct<parameter> *call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the current preedit state.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<structname>XIMPreeditStateNotifyCallbackStruct</structname>
-structure is defined as follows:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XIMPreeditStateNotifyCallbackStruct</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct _XIMPreeditStateNotifyCallbackStruct {
- XIMPreeditState state;
-} XIMPreeditStateNotifyCallbackStruct;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-</para>
-<para>
-<!-- .LP -->
-Because this <acronym>XIC</acronym> value is optional, a client should call
-<function>XGetIMValues</function>
-with argument
-<symbol>XNQueryICValuesList</symbol>
-before using this argument.
-</para>
-</sect4>
-<sect4 id="Preedit_and_Status_Callbacks">
-<title>Preedit and Status Callbacks</title>
-<!-- .XS -->
-<!-- (SN Preedit and Status Callbacks -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-A client that wants to support the input style
-<symbol>XIMPreeditCallbacks</symbol>
-must provide a set of preedit callbacks to the input method.
-The set of preedit callbacks is as follows:
-</para>
-<indexterm significance="preferred"><primary>XNPreeditStartCallback</primary></indexterm>
-<indexterm significance="preferred"><primary>XNPreeditDoneCallback</primary></indexterm>
-<indexterm significance="preferred"><primary>XNPreeditDrawCallback</primary></indexterm>
-<indexterm significance="preferred"><primary>XNPreeditCaretCallback</primary></indexterm>
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <tbody>
- <row>
- <entry><symbol>XNPreeditStartCallback</symbol></entry>
- <entry>This is called when the input method starts preedit.</entry>
- </row>
- <row>
- <entry><symbol>XNPreeditDoneCallback</symbol></entry>
- <entry>This is called when the input method stops preedit.</entry>
- </row>
- <row>
- <entry><symbol>XNPreeditDrawCallback</symbol></entry>
- <entry>This is called when a number of preedit keystrokes should be echoed.</entry>
- </row>
- <row>
- <entry><symbol>XNPreeditCaretCallback</symbol></entry>
- <entry>This is called to move the text insertion point within the preedit string.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-A client that wants to support the input style
-<symbol>XIMStatusCallbacks</symbol>
-must provide a set of status callbacks to the input method.
-The set of status callbacks is as follows:
-</para>
-
-<indexterm significance="preferred"><primary>XNStatusStartCallback</primary></indexterm>
-<indexterm significance="preferred"><primary>XNStatusDoneCallback</primary></indexterm>
-<indexterm significance="preferred"><primary>XNStatusDrawCallback</primary></indexterm>
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <tbody>
- <row>
- <entry><symbol>XNStatusStartCallback</symbol></entry>
- <entry>This is called when the input method initializes the status area.</entry>
- </row>
- <row>
- <entry><symbol>XNStatusDoneCallback</symbol></entry>
- <entry>This is called when the input method no longer needs the status area.</entry>
- </row>
- <row>
- <entry><symbol>XNStatusDrawCallback</symbol></entry>
- <entry>This is called when updating of the status area is required.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-<para>
-<!-- .LP -->
-The value of any status or preedit argument is a pointer
-to a structure of type
-<structname>XIMCallback</structname>.
-<indexterm significance="preferred"><primary>XIMProc</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMCallback</primary></indexterm>
-<!-- .sM -->
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef void (*XIMProc)();
-
-typedef struct {
- XPointer client_data;
- XIMProc callback;
-} XIMCallback;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Each callback has some particular semantics and will carry the data
-that expresses the environment necessary to the client
-into a specific data structure.
-This paragraph only describes the arguments to be used to set
-the callback.
-</para>
-<para>
-<!-- .LP -->
-Setting any of these values while doing preedit
-may cause unexpected results.
-</para>
-</sect4>
-</sect3>
-</sect2>
-<sect2 id="Input_Method_Callback_Semantics">
-<title>Input Method Callback Semantics</title>
-<!-- .XS -->
-<!-- (SN Input Method Callback Semantics -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<acronym>XIM</acronym> callbacks are procedures defined by clients or text drawing packages
-that are to be called from the input method when selected events occur.
-Most clients will use a text editing package or a toolkit
-and, hence, will not need to define such callbacks.
-This section defines the callback semantics, when they are triggered,
-and what their arguments are.
-This information is mostly useful for X toolkit implementors.
-</para>
-<para>
-<!-- .LP -->
-Callbacks are mostly provided so that clients (or text editing
-packages) can implement on-the-spot preediting in their own window.
-In that case,
-the input method needs to communicate and synchronize with the client.
-The input method needs to communicate changes in the preedit window
-when it is under control of the client.
-Those callbacks allow the client to initialize the preedit area,
-display a new preedit string,
-move the text insertion point during preedit,
-terminate preedit, or update the status area.
-</para>
-<para>
-<!-- .LP -->
-All callback procedures follow the generic prototype:
-<indexterm significance="preferred"><primary>CallbackPrototype</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>CallbackPrototype</replaceable></function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>SomeType<parameter> call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies data specific to the callback.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The call_data argument is a structure that expresses the arguments needed
-to achieve the semantics;
-that is,
-it is a specific data structure appropriate to the callback.
-In cases where no data is needed in the callback,
-this call_data argument is NULL.
-The client_data argument is a closure that has been initially specified
-by the client when specifying the callback and passed back.
-It may serve, for example, to inherit application context in the callback.
-</para>
-<para>
-<!-- .LP -->
-The following paragraphs describe the programming semantics
-and specific data structure associated with the different reasons.
-</para>
-<sect3 id="Geometry_Callback_b">
-<title>Geometry Callback</title>
-<!-- .XS -->
-<!-- (SN Geometry Callback -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The geometry callback is triggered by the input method
-to indicate that it wants the client to negotiate geometry.
-The generic prototype is as follows:
-<indexterm significance="preferred"><primary>GeometryCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>GeometryCallback</replaceable></function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XPointer<parameter> call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Not used for this callback and always passed as NULL.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The callback is called with a NULL call_data argument.
-</para>
-</sect3>
-<sect3 id="Destroy_Callback_c">
-<title>Destroy Callback</title>
-<!-- .XS -->
-<!-- (SN Destroy Callback -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The destroy callback is triggered by the input method
-when it stops service for any reason.
-After the callback is invoked, the input context will be freed by Xlib.
-The generic prototype is as follows:
-<indexterm significance="preferred"><primary>DestroyCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>DestroyCallback</replaceable></function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XPointer<parameter> call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Not used for this callback and always passed as NULL.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The callback is called with a NULL call_data argument.
-</para>
-</sect3>
-<sect3 id="String_Conversion_Callback_b">
-<title>String Conversion Callback</title>
-<!-- .XS -->
-<!-- (SN String Conversion Callback -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The string conversion callback is triggered by the input method
-to request the client to return the string to be converted. The
-returned string may be either a multibyte or wide character string,
-with an encoding matching the locale bound to the input context.
-The callback prototype is as follows:
-<indexterm significance="preferred"><primary>StringConversionCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>StringConversionCallback</replaceable></function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XIMStringConversionCallbackStruct<parameter> *call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input method.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the amount of the string to be converted.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The callback is passed an
-<structname>XIMStringConversionCallbackStruct</structname>
-structure in the call_data argument.
-The text member is an
-<structname>XIMStringConversionText</structname>
-structure (see section 13.5.6.9) to be filled in by the client
-and describes the text to be sent to the input method.
-The data pointed to by the
-string and feedback elements of the
-<structname>XIMStringConversionText</structname>
-structure will be freed using
-<function>XFree</function>
-by the input method
-after the callback returns. So the client should not point to
-internal buffers that are critical to the client.
-Similarly, because the feedback element is currently reserved for future
-use, the client should set feedback to NULL to prevent the library from
-freeing memory at some random location due to an uninitialized pointer.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XIMStringConversionCallbackStruct</structname>
-structure is defined as follows:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XIMStringConversionCallbackStruct</primary></indexterm>
-<!-- .sM -->
-</para>
-<!-- .LP -->
-<literallayout class="monospaced">
-typedef struct _XIMStringConversionCallbackStruct {
- XIMStringConversionPosition position;
- XIMCaretDirection direction;
- short factor;
- XIMStringConversionOperation operation;
- XIMStringConversionText *text;
-} XIMStringConversionCallbackStruct;
-
-typedef short XIMStringConversionPosition;
-
-typedef unsigned short XIMStringConversionOperation;
-
-#define XIMStringConversionSubstitution (0x0001)
-#define XIMStringConversionRetrieval (0x0001)
-
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<type>XIMStringConversionPosition</type>
-specifies the starting position of the string to be returned
-in the
-<structname>XIMStringConversionText</structname>
-structure. The value identifies a position, in units of characters,
-relative to the client's cursor position in the client's buffer.
-</para>
-<para>
-<!-- .LP -->
-The ending position of the text buffer is determined by
-the direction and factor members. Specifically, it is the character position
-relative to the starting point as defined by the
-<structname>XIMCaretDirection</structname>.
-The factor member of
-<structname>XIMStringConversionCallbackStruct</structname>
-specifies the number of
-<structname>XIMCaretDirection</structname>
-positions to be applied. For example, if the direction specifies
-<constant>XIMLineEnd</constant>
-and factor is 1, then all characters from the starting position to
-the end of the current display line are returned. If the direction
-specifies
-<constant>XIMForwardChar</constant>
-or
-<constant>XIMBackwardChar</constant>,
-then the factor specifies a relative position, indicated in characters,
-from the starting position.
-</para>
-<para>
-<!-- .LP -->
-<type>XIMStringConversionOperation</type>
-specifies whether the string to be converted should be
-deleted (substitution) or copied (retrieval) from the client's
-buffer. When the
-<type>XIMStringConversionOperation</type>
-is
-<symbol>XIMStringConversionSubstitution</symbol>,
-the client must delete the string to be converted from its own buffer.
-When the
-<type>XIMStringConversionOperation</type>
-is
-<symbol>XIMStringConversionRetrieval</symbol>,
-the client must not delete the string to be converted from its buffer.
-The substitute operation is typically used for reconversion and
-transliteration conversion,
-while the retrieval operation is typically used for context-sensitive
-conversion.
-</para>
-</sect3>
-<sect3 id="Preedit_State_Callbacks">
-<title>Preedit State Callbacks</title>
-<!-- .XS -->
-<!-- (SN Preedit State Callbacks -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-When the input method turns preediting on or off, a
-<function><replaceable>PreeditStartCallback</replaceable></function>
-or
-<function><replaceable>PreeditDoneCallback</replaceable></function>
-callback is triggered to let the toolkit do the setup
-or the cleanup for the preedit region.
-<indexterm significance="preferred"><primary>PreeditStartCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function><replaceable>PreeditStartCallback</replaceable></function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XPointer<parameter> call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Not used for this callback and always passed as NULL.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-When preedit starts on the specified input context,
-the callback is called with a NULL call_data argument.
-<function><replaceable>PreeditStartCallback</replaceable></function>
-will return the maximum size of the preedit string.
-A positive number indicates the maximum number of bytes allowed
-in the preedit string,
-and a value of -1 indicates there is no limit.
-<indexterm significance="preferred"><primary>PreeditDoneCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>PreeditDoneCallback</replaceable></function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XPointer<parameter> call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Not used for this callback and always passed as NULL.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-When preedit stops on the specified input context,
-the callback is called with a NULL call_data argument.
-The client can release the data allocated by
-<function><replaceable>PreeditStartCallback</replaceable></function>.
-</para>
-<para>
-<!-- .LP -->
-<function><replaceable>PreeditStartCallback</replaceable></function>
-should initialize appropriate data needed for
-displaying preedit information and for handling further
-<function><replaceable>PreeditDrawCallback</replaceable></function>
-calls.
-Once
-<function><replaceable>PreeditStartCallback</replaceable></function>
-is called, it will not be called again before
-<function><replaceable>PreeditDoneCallback</replaceable></function>
-has been called.
-</para>
-</sect3>
-<sect3 id="Preedit_Draw_Callback">
-<title>Preedit Draw Callback</title>
-<!-- .XS -->
-<!-- (SN Preedit Draw Callback -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This callback is triggered to draw and insert, delete or replace,
-preedit text in the preedit region.
-The preedit text may include unconverted input text such as Japanese Kana,
-converted text such as Japanese Kanji characters, or characters of both kinds.
-That string is either a multibyte or wide character string,
-whose encoding matches the locale bound to the input context.
-The callback prototype
-is as follows:
-<indexterm significance="preferred"><primary>PreeditDrawCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>PreeditDrawCallback</replaceable></function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XIMPreeditDrawCallbackStruct<parameter> *call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the preedit drawing information.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The callback is passed an
-<structname>XIMPreeditDrawCallbackStruct</structname>
-structure in the call_data argument.
-The text member of this structure contains the text to be drawn.
-After the string has been drawn,
-the caret should be moved to the specified location.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XIMPreeditDrawCallbackStruct</structname>
-structure is defined as follows:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XIMPreeditDrawCallbackStruct</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct _XIMPreeditDrawCallbackStruct {
- int caret; /* Cursor offset within preedit string */
- int chg_first; /* Starting change position */
- int chg_length; /* Length of the change in character count */
- XIMText *text;
-} XIMPreeditDrawCallbackStruct;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The client must keep updating a buffer of the preedit text
-and the callback arguments referring to indexes in that buffer.
-The call_data fields have specific meanings according to the operation,
-as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-To indicate text deletion,
-the call_data member specifies a NULL text field.
-The text to be deleted is then the current text in the buffer
-from position chg_first (starting at zero) on a character length
-of chg_length.
- </para>
- </listitem>
- <listitem>
- <para>
-When text is non-NULL,
-it indicates insertion or replacement of text in the buffer.
- </para>
- </listitem>
- <listitem>
- <para>
-The chg_length member
-identifies the number of characters in the current preedit buffer
-that are affected by this call.
-A positive chg_length indicates that chg_length number of characters, starting
-at chg_first, must be deleted or must be replaced by text, whose length is
-specified in the
-<structname>XIMText</structname>
-structure.
- </para>
- </listitem>
- <listitem>
- <para>
-A chg_length value of zero indicates that text must be inserted
-right at the position specified by chg_first.
-A value of zero for chg_first specifies the first character in the buffer.
- </para>
- </listitem>
- <listitem>
- <para>
-chg_length and chg_first combine to identify the modification required to
-the preedit buffer; beginning at chg_first, replace chg_length number of
-characters with the text in the supplied
-<structname>XIMText</structname>
-structure. For example, suppose the preedit buffer contains the string "ABCDE".
- </para>
- </listitem>
- <listitem>
- <para>
-<literallayout class="monospaced">
-<!-- .ft C -->
-Text: A B C D E
- ^ ^ ^ ^ ^ ^
-CharPos: 0 1 2 3 4 5
-<!-- .sp -->
-<!-- .ft P -->
-</literallayout>
-The CharPos in the diagram shows the location of the character position
-relative to the character.
- </para>
- </listitem>
- <listitem>
- <para>
-If the value of chg_first is 1 and the value of chg_length is 3, this
-says to replace 3 characters beginning at character position 1 with the
-string in the
-<structname>XIMText</structname>
-structure.
-Hence, <acronym>BCD</acronym> would be replaced by the value in the structure.
- </para>
- </listitem>
- <listitem>
- <para>
-Though chg_length and chg_first are both signed integers they will
-never have a negative value.
- </para>
- </listitem>
- <listitem>
- <para>
-The caret member
-identifies the character position before which the cursor should
-be placed - after modification to the preedit buffer has been completed.
-For example, if caret is zero, the cursor is at
-the beginning of the buffer. If the caret is one, the cursor is between
-the first and second character.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XIMText</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 1.5i 3i -->
-typedef struct _XIMText {
- unsigned short length;
- XIMFeedback * feedback;
- Bool encoding_is_wchar;
- union {
- char * multi_byte;
- wchar_t * wide_char;
- } string;
-} XIMText;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The text string passed is actually a structure specifying as follows:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-The length member is the text length in characters.
- </para>
- </listitem>
- <listitem>
- <para>
-The encoding_is_wchar member is a value that indicates
-if the text string is encoded in wide character or multibyte format.
-The text string may be passed either as multibyte or as wide character;
-the input method controls in which form data is passed.
-The client's
-callback routine must be able to handle data passed in either form.
- </para>
- </listitem>
- <listitem>
- <para>
-The string member is the text string.
- </para>
- </listitem>
- <listitem>
- <para>
-The feedback member indicates rendering type for each character in the
-string member.
-If string is NULL (indicating that only highlighting of the existing
-preedit buffer should be updated), feedback points to length highlight
-elements that should be applied to the existing preedit buffer, beginning
-at chg_first.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-The feedback member expresses the types of rendering feedback
-the callback should apply when drawing text.
-Rendering of the text to be drawn is specified either in generic ways
-(for example, primary, secondary) or in specific ways (reverse, underline).
-When generic indications are given,
-the client is free to choose the rendering style.
-It is necessary, however, that primary and secondary be mapped
-to two distinct rendering styles.
-</para>
-<para>
-<!-- .LP -->
-If an input method wants to control display of the preedit string, an
-input method can indicate the visibility hints using feedbacks in
-a specific way.
-The
-<symbol>XIMVisibleToForward</symbol>,
-<symbol>XIMVisibleToBackword</symbol>,
-and
-<symbol>XIMVisibleToCenter</symbol>
-masks are exclusively used for these visibility hints.
-The
-<symbol>XIMVisibleToForward</symbol>
-mask
-indicates that the preedit text is preferably displayed in the
-primary draw direction from the
-caret position in the preedit area forward.
-The
-<symbol>XIMVisibleToBackword</symbol>
-mask
-indicates that the preedit text is preferably displayed from
-the caret position in the preedit area backward, relative to the primary
-draw direction.
-The
-<symbol>XIMVisibleToCenter</symbol>
-mask
-indicates that the preedit text is preferably displayed with
-the caret position in the preedit area centered.
-</para>
-<para>
-<!-- .LP -->
-The insertion point of the preedit string could exist outside of
-the visible area when visibility hints are used.
-Only one of the
-masks
-is valid for the entire preedit string, and only one character
-can hold one of these feedbacks for a given input context at one time.
-This feedback may be OR'ed together with another highlight (such as
-<symbol>XIMReverse</symbol>).
-Only the most recently set feedback is valid, and any previous
-feedback is automatically canceled. This is a hint to the client, and
-the client is free to choose how to display the preedit string.
-</para>
-<para>
-<!-- .LP -->
-The feedback member also specifies how rendering of the text argument
-should be performed.
-If the feedback is NULL,
-the callback should apply the same feedback as is used for the surrounding
-characters in the preedit buffer; if chg_first is at a highlight boundary,
-the client can choose which of the two highlights to use.
-If feedback is not NULL, feedback specifies an array defining the
-rendering for each
-character of the string, and the length of the array is thus length.
-</para>
-<para>
-<!-- .LP -->
-If an input method wants to indicate that it is only updating the feedback of
-the preedit text without changing the content of it,
-the
-<structname>XIMText</structname>
-structure will contain a NULL value for the string field,
-the number of characters affected (relative to chg_first)
-will be in the length field,
-and the feedback field will point to an array of
-<type>XIMFeedback</type>.
-</para>
-<para>
-<!-- .LP -->
-Each element in the feedback array is a bitmask represented by a value of type
-<type>XIMFeedback</type>.
-The valid mask names are as follows:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XIMReverse</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMUnderline</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMHighlight</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPrimary</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMSecondary</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMTertiary</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMVisibleToForward</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMVisibleToBackward</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMVisibleToCenter</primary></indexterm>
-<!-- .sM -->
-</para>
-<literallayout class="monospaced">
-typedef unsigned long XIMFeedback;
-
-#define XIMReverse 1L
-#define XIMUnderline (1L&lt;&lt;1)
-#define XIMHighlight (1L&lt;&lt;2)
-#define XIMPrimary (1L&lt;&lt;5)*
-#define XIMSecondary (1L&lt;&lt;6)*
-#define XIMTertiary (1L&lt;&lt;7)*
-#define XIMVisibleToForward (1L&lt;&lt;8)
-#define XIMVisibleToBackward (1L&lt;&lt;9)
-#define XIMVisibleToCenter (1L&lt;&lt;10)
-
-*† The values for XIMPrimary, XIMSecondary, and XIMTertiary were incorrectly defined in
-the R5 specification. The X Consortium’s X11R5 implementation correctly
-implemented the values for these highlights. The value of these highlights has
-been corrected in this specification to agree with the values in the
-Consortium’s X11R5 and X11R6 implementations.
-
-</literallayout>
-
-<para>
-<!-- .LP -->
-Characters drawn with the
-<symbol>XIMReverse</symbol>
-highlight should be drawn by swapping the foreground and background colors
-used to draw normal, unhighlighted characters.
-Characters drawn with the
-<symbol>XIMUnderline</symbol>
-highlight should be underlined.
-Characters drawn with the
-<symbol>XIMHighlight</symbol>,
-<symbol>XIMPrimary</symbol>,
-<symbol>XIMSecondary</symbol>,
-and
-<symbol>XIMTertiary</symbol>
-highlights should be drawn in some unique manner that must be different
-from
-<symbol>XIMReverse</symbol>
-and
-<symbol>XIMUnderline</symbol>.
-<!-- .FS \(dg -->
-The values for
-<symbol>XIMPrimary</symbol>,
-<symbol>XIMSecondary</symbol>,
-and
-<symbol>XIMTertiary</symbol>
-were incorrectly defined in the R5 specification.
-The X Consortium's X11R5
-implementation correctly implemented the values for these highlights.
-The value of these highlights has been corrected in this specification
-to agree with the values in the Consortium's X11R5 and X11R6 implementations.
-<!-- .FE -->
-</para>
-</sect3>
-<sect3 id="Preedit_Caret_Callback">
-<title>Preedit Caret Callback</title>
-<!-- .XS -->
-<!-- (SN Preedit Caret Callback -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-An input method may have its own navigation keys to allow the user
-to move the text insertion point in the preedit area
-(for example, to move backward or forward).
-Consequently, input method needs to indicate to the client that it
-should move the text insertion point.
-It then calls the PreeditCaretCallback.
-<indexterm significance="preferred"><primary>PreeditCaretCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>PreeditCaretCallback</replaceable></function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XIMPreeditCaretCallbackStruct<parameter> *call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the preedit caret information.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The input method will trigger PreeditCaretCallback
-to move the text insertion point during preedit.
-The call_data argument contains a pointer to an
-<structname>XIMPreeditCaretCallbackStruct</structname>
-structure,
-which indicates where the caret should be moved.
-The callback must move the insertion point to its new location
-and return, in field position, the new offset value from the initial position.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XIMPreeditCaretCallbackStruct</structname>
-structure is defined as follows:
-<indexterm significance="preferred"><primary>XIMPreeditCaretCallbackStruct</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct _XIMPreeditCaretCallbackStruct {
- int position; /* Caret offset within preedit string */
- XIMCaretDirection direction; /* Caret moves direction */
- XIMCaretStyle style; /* Feedback of the caret */
-} XIMPreeditCaretCallbackStruct;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<structname>XIMCaretStyle</structname>
-structure is defined as follows:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XIMCaretStyle</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef enum {
- XIMIsInvisible, /* Disable caret feedback */
- XIMIsPrimary, /* <acronym>UI</acronym> defined caret feedback */
- XIMIsSecondary, /* <acronym>UI</acronym> defined caret feedback */
-} XIMCaretStyle;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<structname>XIMCaretDirection</structname>
-structure is defined as follows:
-<indexterm significance="preferred"><primary>XIMCaretDirection</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef enum {
- XIMForwardChar, XIMBackwardChar,
- XIMForwardWord, XIMBackwardWord,
- XIMCaretUp, XIMCaretDown,
- XIMNextLine, XIMPreviousLine,
- XIMLineStart, XIMLineEnd,
- XIMAbsolutePosition,
- XIMDontChange,
- } XIMCaretDirection;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-These values are defined as follows:
-</para>
-<indexterm significance="preferred"><primary>XIMForwardChar</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMBackwardChar</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMForwardWord</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMBackwardWord</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMCaretUp</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMCaretDown</primary></indexterm>
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <tbody>
- <row>
- <entry><constant>XIMForwardChar</constant></entry>
- <entry>Move the caret forward one character position.</entry>
- </row>
- <row>
- <entry><constant>XIMBackwardChar</constant></entry>
- <entry>Move the caret backward one character position.</entry>
- </row>
- <row>
- <entry><constant>XIMForwardWord</constant></entry>
- <entry>Move the caret forward one word.</entry>
- </row>
- <row>
- <entry><constant>XIMBackwardWord</constant></entry>
- <entry>Move the caret backward one word.</entry>
- </row>
- <row>
- <entry><constant>XIMCaretUp</constant></entry>
- <entry>Move the caret up one line keeping the current horizontal offset.</entry>
- </row>
- <row>
- <entry><constant>XIMCaretDown</constant></entry>
- <entry>Move the caret down one line keeping the current horizontal offset.</entry>
- </row>
- <row>
- <entry><constant>XIMPreviousLine</constant></entry>
- <entry>Move the caret to the beginning of the previous line.</entry>
- </row>
- <row>
- <entry><constant>XIMNextLine</constant></entry>
- <entry>Move the caret to the beginning of the next line.</entry>
- </row>
- <row>
- <entry><constant>XIMLineStart</constant></entry>
- <entry>Move the caret to the beginning of the current display line that contains the caret.</entry>
- </row>
- <row>
- <entry><constant>XIMLineEnd</constant></entry>
- <entry>Move the caret to the end of the current display line that contains the caret.</entry>
- </row>
- <row>
- <entry><constant>XIMAbsolutePosition</constant></entry>
- <entry>The callback must move to the location specified by the position field
- of the callback data, indicated in characters, starting from the beginning
- of the preedit text.
- Hence, a value of zero means move back to the beginning of the preedit text.</entry>
- </row>
- <row>
- <entry><constant>XIMDontChange</constant></entry>
- <entry>The caret position does not change.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<indexterm significance="preferred"><primary>XIMNextLine</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMPreviousLine</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMLineStart</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMLineEnd</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMAbsolutePosition</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMDontChange</primary></indexterm>
-</sect3>
-<sect3 id="Status_Callbacks">
-<title>Status Callbacks</title>
-<!-- .XS -->
-<!-- (SN Status Callbacks -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-An input method may communicate changes in the status of an input context
-(for example, created, destroyed, or focus changes) with three status
-callbacks: StatusStartCallback, StatusDoneCallback, and StatusDrawCallback.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-When the input context is created or gains focus,
-the input method calls the StatusStartCallback callback.
-<indexterm significance="preferred"><primary>StatusStartCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>StatusStartCallback</replaceable></function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XPointer<parameter> call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Not used for this callback and always passed as NULL.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The callback should initialize appropriate data for displaying status
-and for responding to StatusDrawCallback calls.
-Once StatusStartCallback is called,
-it will not be called again before StatusDoneCallback has been called.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-When an input context
-is destroyed or when it loses focus, the input method calls StatusDoneCallback.
-<indexterm significance="preferred"><primary>StatusDoneCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>StatusDoneCallback</replaceable></function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XPointer<parameter> call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Not used for this callback and always passed as NULL.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The callback may release any data allocated on
-<function>StatusStart</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-When an input context status has to be updated, the input method calls
-StatusDrawCallback.
-<indexterm significance="preferred"><primary>StatusDrawCallback</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function><replaceable>StatusDrawCallback</replaceable></function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XPointer<parameter> client_data</parameter></paramdef>
- <paramdef>XIMStatusDrawCallbackStruct<parameter> *call_data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>client_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the additional client data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>call_data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the status drawing information.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The callback should update the status area by either drawing a string
-or imaging a bitmap in the status area.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XIMStatusDataType</structname>
-and
-<structname>XIMStatusDrawCallbackStruct</structname>
-structures are defined as follows:
-<indexterm significance="preferred"><primary>XIMStatusDataType</primary></indexterm>
-<indexterm significance="preferred"><primary>XIMStatusDrawCallbackStruct</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 1i 3i -->
-<!-- .ta .5i 1i 3i -->
-typedef enum {
- XIMTextType,
- XIMBitmapType,
-} XIMStatusDataType;
-
-typedef struct _XIMStatusDrawCallbackStruct {
- XIMStatusDataType type;
- union {
- XIMText *text;
- Pixmap bitmap;
- } data;
-} XIMStatusDrawCallbackStruct;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-</para>
-<para>
-<!-- .LP -->
-The feedback styles
-<symbol>XIMVisibleToForward</symbol>,
-<symbol>XIMVisibleToBackword</symbol>,
-and
-<symbol>XIMVisibleToCenter</symbol>
-are not relevant and will not appear in the
-<type>XIMFeedback</type>
-element of the
-<structname>XIMText</structname>
-structure.
-</para>
-<para>
-<!-- .LP -->
-</para>
-</sect3>
-</sect2>
-<sect2 id="Event_Filtering_b">
-<title>Event Filtering</title>
-<!-- .XS -->
-<!-- (SN Event Filtering -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides the ability for an input method
-to register a filter internal to Xlib.
-This filter is called by a client (or toolkit) by calling
-<function>XFilterEvent</function>
-after calling
-<function>XNextEvent</function>.
-Any client that uses the
-<type>XIM</type>
-interface should call
-<function>XFilterEvent</function>
-to allow input methods to process their events without knowledge
-of the client's dispatching mechanism.
-A client's user interface policy may determine the priority
-of event filters with respect to other event-handling mechanisms
-(for example, modal grabs).
-</para>
-<para>
-<!-- .LP -->
-Clients may not know how many filters there are, if any,
-and what they do.
-They may only know if an event has been filtered on return of
-<function>XFilterEvent</function>.
-Clients should discard filtered events.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To filter an event, use
-<function>XFilterEvent</function>.
-<indexterm significance="preferred"><primary>XFilterEvent</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XFilterEvent</function></funcdef>
- <paramdef>XEvent<parameter> *event</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<!-- .ds Ev event to filter -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>event</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the (Ev.
-<!-- .ds Wi for which the filter is to be applied -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window (Wi.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If the window argument is
-<symbol>None</symbol>,
-<function>XFilterEvent</function>
-applies the filter to the window specified in the
-<structname>XEvent</structname>
-structure.
-The window argument is provided so that layers above Xlib
-that do event redirection can indicate to which window an event
-has been redirected.
-</para>
-<para>
-<!-- .LP -->
-If
-<function>XFilterEvent</function>
-returns
-<symbol>True</symbol>,
-then some input method has filtered the event,
-and the client should discard the event.
-If
-<function>XFilterEvent</function>
-returns
-<symbol>False</symbol>,
-then the client should continue processing the event.
-</para>
-<para>
-<!-- .LP -->
-If a grab has occurred in the client and
-<function>XFilterEvent</function>
-returns
-<symbol>True</symbol>,
-the client should ungrab the keyboard.
-</para>
-</sect2>
-<sect2 id="Getting_Keyboard_Input_b">
-<title>Getting Keyboard Input</title>
-<!-- .XS -->
-<!-- (SN Getting Keyboard Input -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To get composed input from an input method,
-use
-<function>XmbLookupString</function>
-or
-<function>XwcLookupString</function>.
-<indexterm significance="preferred"><primary>XmbLookupString</primary></indexterm>
-<indexterm significance="preferred"><primary>XwcLookupString</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XmbLookupString</function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XKeyPressedEvent<parameter> *event</parameter></paramdef>
- <paramdef>char<parameter> *buffer_return</parameter></paramdef>
- <paramdef>int<parameter> bytes_buffer</parameter></paramdef>
- <paramdef>KeySym<parameter> *keysym_return</parameter></paramdef>
- <paramdef>Status<parameter> *status_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XwcLookupString</function></funcdef>
- <paramdef>XIC<parameter> ic</parameter></paramdef>
- <paramdef>XKeyPressedEvent<parameter> *event</parameter></paramdef>
- <paramdef>wchar_t<parameter> *buffer_return</parameter></paramdef>
- <paramdef>int<parameter> wchars_buffer</parameter></paramdef>
- <paramdef>KeySym<parameter> *keysym_return</parameter></paramdef>
- <paramdef>Status<parameter> *status_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ic</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the input context.
-<!-- .ds Ev key event to be used -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>event</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the (Ev.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>buffer_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns a multibyte string or wide character string (if any)
-from the input method.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bytes_buffer</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>wchars_buffer</emphasis>
- </term>
- <listitem>
- <para>
-Specifies space available in the return buffer.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the KeySym computed from the event if this argument is not NULL.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>status_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns a value indicating what kind of data is returned.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XmbLookupString</function>
-and
-<function>XwcLookupString</function>
-functions return the string from the input method specified
-in the buffer_return argument.
-If no string is returned,
-the buffer_return argument is unchanged.
-</para>
-<para>
-<!-- .LP -->
-The KeySym into which the KeyCode from the event was mapped is returned
-in the keysym_return argument if it is non-NULL and the status_return
-argument indicates that a KeySym was returned.
-If both a string and a KeySym are returned,
-the KeySym value does not necessarily correspond to the string returned.
-</para>
-<para>
-<!-- .LP -->
-<function>XmbLookupString</function>
-returns the length of the string in bytes, and
-<function>XwcLookupString</function>
-returns the length of the string in characters.
-Both
-<function>XmbLookupString</function>
-and
-<function>XwcLookupString</function>
-return text in the encoding of the locale bound to the input method
-of the specified input context.
-</para>
-<para>
-<!-- .LP -->
-Each string returned by
-<function>XmbLookupString</function>
-and
-<function>XwcLookupString</function>
-begins in the initial state of the encoding of the locale
-(if the encoding of the locale is state-dependent).
-<!-- .NT -->
-<note><para>
-To insure proper input processing,
-it is essential that the client pass only
-<symbol>KeyPress</symbol>
-events to
-<function>XmbLookupString</function>
-and
-<function>XwcLookupString</function>.
-Their behavior when a client passes a
-<symbol>KeyRelease</symbol>
-event is undefined.
-</para></note>
-<!-- .NE -->
-</para>
-<para>
-<!-- .LP -->
-Clients should check the status_return argument before
-using the other returned values.
-These two functions both return a value to status_return
-that indicates what has been returned in the other arguments.
-The possible values returned are:
-</para>
-
-<informaltable>
- <tgroup cols='2' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <tbody>
- <row>
- <entry><symbol>XBufferOverflow</symbol></entry>
- <entry>The input string to be returned is too large for the supplied buffer_return.
- The required size
- (<function>XmbLookupString</function>
- in bytes;
- <function>XwcLookupString</function>
- in characters) is returned as the value of the function,
- and the contents of buffer_return and keysym_return are not modified.
- The client should recall the function with the same event
- and a buffer of adequate size to obtain the string.</entry>
- </row>
- <row>
- <entry><symbol>XLookupNone</symbol></entry>
- <entry>No consistent input has been composed so far.
- The contents of buffer_return and keysym_return are not modified,
- and the function returns zero.</entry>
- </row>
- <row>
- <entry><symbol>XLookupChars</symbol></entry>
- <entry>Some input characters have been composed.
- They are placed in the buffer_return argument,
- and the string length is returned as the value of the function.
- The string is encoded in the locale bound to the input context.
- The content of the keysym_return argument is not modified.</entry>
- </row>
- <row>
- <entry><symbol>XLookupKeySym</symbol></entry>
- <entry>A KeySym has been returned instead of a string
- and is returned in keysym_return.
- The content of the buffer_return argument is not modified,
- and the function returns zero.</entry>
- </row>
- <row>
- <entry><symbol>XLookupBoth</symbol></entry>
- <entry>Both a KeySym and a string are returned;
- <symbol>XLookupChars</symbol>
- and
- <symbol>XLookupKeySym</symbol>
- occur simultaneously.</entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-<!-- .LP -->
-It does not make any difference if the input context passed as an argument to
-<function>XmbLookupString</function>
-and
-<function>XwcLookupString</function>
-is the one currently in possession of the focus or not.
-Input may have been composed within an input context before it lost the focus,
-and that input may be returned on subsequent calls to
-<function>XmbLookupString</function>
-or
-<function>XwcLookupString</function>
-even though it does not have any more keyboard focus.
-</para>
-</sect2>
-<sect2 id="Input_Method_Conventions">
-<title>Input Method Conventions</title>
-<!-- .XS -->
-<!-- (SN Input Method Conventions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The input method architecture is transparent to the client.
-However, clients should respect a number of conventions in order
-to work properly.
-Clients must also be aware of possible effects of synchronization
-between input method and library in the case of a remote input server.
-</para>
-<sect3 id="Client_Conventions">
-<title>Client Conventions</title>
-<!-- .XS -->
-<!-- (SN Client Conventions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-A well-behaved client (or toolkit) should first query the input method style.
-If the client cannot satisfy the requirements of the supported styles
-(in terms of geometry management or callbacks),
-it should negotiate with the user continuation of the program
-or raise an exception or error of some sort.
-</para>
-</sect3>
-<sect3 id="Synchronization_Conventions">
-<title>Synchronization Conventions</title>
-<!-- .XS -->
-<!-- (SN Synchronization Conventions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-A
-<symbol>KeyPress</symbol>
-event with a KeyCode of zero is used exclusively as a
-signal that an input method has composed input that can be returned by
-<function>XmbLookupString</function>
-or
-<function>XwcLookupString</function>.
-No other use is made of a
-<symbol>KeyPress</symbol>
-event with KeyCode of zero.
-</para>
-<para>
-<!-- .LP -->
-Such an event may be generated by either a front-end
-or a back-end input method in an implementation-dependent manner.
-Some possible ways to generate this event include:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-A synthetic event sent by an input method server
- </para>
- </listitem>
- <listitem>
- <para>
-An artificial event created by a input method filter and pushed
-onto a client's event queue
- </para>
- </listitem>
- <listitem>
- <para>
-A
-<symbol>KeyPress</symbol>
-event whose KeyCode value is modified by an input method filter
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-When callback support is specified by the client,
-input methods will not take action unless they explicitly
-called back the client and obtained no response
-(the callback is not specified or returned invalid data).
-</para>
-</sect3>
-</sect2>
-</sect1>
-<sect1 id="String_Constants">
-<title>String Constants</title>
-<!-- .XS -->
-<!-- (SN String Constants -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The following symbols for string constants are defined in
-&lt;X11/Xlib.h&gt; .
-Although they are shown here with particular macro definitions,
-they may be implemented as macros, as global symbols, or as a
-mixture of the two. The string pointer value itself
-is not significant; clients must not assume that inequality of two
-values implies inequality of the actual string data.
-</para>
-
-<literallayout class="monospaced">
-#define XNVaNestedList "XNVaNestedList"
-#define XNSeparatorofNestedList "separatorofNestedList"
-#define XNQueryInputStyle "queryInputStyle"
-#define XNClientWindow "clientWindow"
-#define XNInputStyle "inputStyle"
-#define XNFocusWindow "focusWindow"
-#define XNResourceName "resourceName"
-#define XNResourceClass "resourceClass"
-#define XNGeometryCallback "geometryCallback"
-#define XNDestroyCallback "destroyCallback"
-#define XNFilterEvents "filterEvents"
-#define XNPreeditStartCallback "preeditStartCallback"
-#define XNPreeditDoneCallback "preeditDoneCallback"
-#define XNPreeditDrawCallback "preeditDrawCallback"
-#define XNPreeditCaretCallback "preeditCaretCallback"
-#define XNPreeditStateNotifyCallback "preeditStateNotifyCallback"
-#define XNPreeditAttributes "preeditAttributes"
-#define XNStatusStartCallback "statusStartCallback"
-#define XNStatusDoneCallback "statusDoneCallback"
-#define XNStatusDrawCallback "statusDrawCallback"
-#define XNStatusAttributes "statusAttributes"
-#define XNArea "area"
-#define XNAreaNeeded "areaNeeded"
-#define XNSpotLocation "spotLocation"
-#define XNColormap "colorMap"
-#define XNStdColormap "stdColorMap"
-#define XNForeground "foreground"
-#define XNBackground "background"
-#define XNBackgroundPixmap "backgroundPixmap"
-#define XNFontSet "fontSet"
-#define XNLineSpace "lineSpace"
-#define XNCursor "cursor"
-#define XNQueryIMValuesList "queryIMValuesList"
-#define XNQueryICValuesList "queryICValuesList"
-#define XNStringConversionCallback "stringConversionCallback"
-#define XNStringConversion "stringConversion"
-#define XNResetState "resetState"
-#define XNHotKey "hotkey"
-#define XNHotKeyState "hotkeyState"
-#define XNPreeditState "preeditState"
-#define XNVisiblePosition "visiblePosition"
-#define XNR6PreeditCallbackBehavior "r6PreeditCallback"
-#define XNRequiredCharSet "requiredCharSet"
-#define XNQueryOrientation "queryOrientation"
-#define XNDirectionalDependentDrawing "directionalDependentDrawing"
-#define XNContextualDrawing "contextualDrawing"
-#define XNBaseFontName "baseFontName"
-#define XNMissingCharSet "missingCharSet"
-#define XNDefaultString "defaultString"
-#define XNOrientation "orientation"
-#define XNFontInfo "fontInfo"
-#define XNOMAutomatic "omAutomatic"
-
-</literallayout>
-
-</sect1>
-</chapter>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<chapter id="locales_and_internationalized_text_functions">
+<title>Locales and Internationalized Text Functions</title>
+
+<para>
+An internationalized application is one that is adaptable to the requirements of different native
+languages, local customs, and character string encodings. The process of adapting the operation
+to a particular native language, local custom, or string encoding is called localization. A goal of
+internationalization is to permit localization without program source modifications or recompilation.
+</para>
+<para>
+As one of the localization mechanisms, Xlib provides an X Input Method (<acronym>XIM</acronym>)
+functional interface for internationalized text input and an X Output Method
+(<acronym>XOM</acronym>) functional interface for internationalized text output.
+</para>
+<para>
+Internationalization in X is based on the concept of a locale. A locale defines the localized
+behavior of a program at run time. Locales affect Xlib in its:
+</para>
+
+<itemizedlist>
+ <listitem><para>Encoding and processing of input method text</para></listitem>
+ <listitem><para>Encoding of resource files and values</para></listitem>
+ <listitem><para>Encoding and imaging of text strings</para></listitem>
+ <listitem><para>Encoding and decoding for inter-client text communication</para></listitem>
+</itemizedlist>
+
+
+<para>
+•
+Encoding and decoding for inter-client text communication
+Characters from various languages are represented in a computer using an encoding.
+Different languages have different encodings, and there are even different
+encodings for the same characters in the same language.
+</para>
+<para>
+This chapter defines support for localized text imaging and text input and describes the locale
+mechanism that controls all locale-dependent Xlib functions. Sets of functions are provided for
+multibyte (char *) text as well as wide character (wchar_t) text in the form supported by the host
+C language environment. The multibyte and wide character functions are equivalent except for
+the form of the text argument.
+</para>
+<para>
+The Xlib internationalization functions are not meant to provide support for
+multilingual applications (mixing multiple languages within a single piece of text),
+but they make it possible to implement applications that work in limited
+fashion with more than one language in independent contexts.
+</para>
+<para>
+The remainder of this chapter discusses:
+</para>
+
+<itemizedlist>
+ <listitem><para>X locale management</para></listitem>
+ <listitem><para>Locale and modifier dependencies</para></listitem>
+ <listitem><para>Variable argument lists</para></listitem>
+ <listitem><para>Output methods</para></listitem>
+ <listitem><para>Input methods</para></listitem>
+ <listitem><para>String constants</para></listitem>
+</itemizedlist>
+
+
+<sect1 id="X_Locale_Management">
+<title>X Locale Management</title>
+<!-- .XS -->
+<!-- (SN X Locale Management -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+X supports one or more of the locales defined by the host environment.
+On implementations that conform to the ANSI C library,
+the locale announcement method is
+<function>setlocale</function>.
+This function configures the locale operation of both
+the host C library and Xlib.
+The operation of Xlib is governed by the LC_CTYPE category;
+this is called the <emphasis remap='I'>current locale</emphasis>.
+An implementation is permitted to provide implementation-dependent
+mechanisms for announcing the locale in addition to
+<function>setlocale</function>.
+</para>
+<para>
+<!-- .LP -->
+On implementations that do not conform to the ANSI C library,
+the locale announcement method is Xlib implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+The mechanism by which the semantic operation of Xlib is defined
+for a specific locale is implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+X is not required to support all the locales supported by the host.
+To determine if the current locale is supported by X, use
+<function>XSupportsLocale</function>.
+</para>
+
+<para>Bool XSupportsLocale()</para>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSupportsLocale</function>
+function returns
+<symbol>True</symbol>
+if Xlib functions are capable of operating under the current locale.
+If it returns
+<symbol>False</symbol>,
+Xlib locale-dependent functions for which the
+<symbol>XLocaleNotSupported</symbol>
+return status is defined will return
+<symbol>XLocaleNotSupported</symbol>.
+Other Xlib locale-dependent routines will operate in the ``C'' locale.
+</para>
+<para>
+<!-- .LP -->
+The client is responsible for selecting its locale and X modifiers.
+Clients should provide a means for the user to override the clients'
+locale selection at client invocation.
+Most single-display X clients operate in a single locale
+for both X and the host processing environment.
+They will configure the locale by calling three functions:
+the host locale configuration function,
+<function>XSupportsLocale</function>,
+and
+<function>XSetLocaleModifiers</function>.
+</para>
+<para>
+<!-- .LP -->
+The semantics of certain categories of X internationalization capabilities
+can be configured by setting modifiers.
+Modifiers are named by implementation-dependent and locale-specific strings.
+The only standard use for this capability at present
+is selecting one of several styles of keyboard input method.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To configure Xlib locale modifiers for the current locale, use
+<function>XSetLocaleModifiers</function>.
+<indexterm significance="preferred"><primary>XSetLocaleModifiers</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetlocalemodifiers'>
+<funcprototype>
+ <funcdef>char *<function>XSetLocaleModifiers</function></funcdef>
+ <paramdef>char<parameter> *modifier_list</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>modifier_list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the modifiers.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetLocaleModifiers</function>
+function sets the X modifiers for the current locale setting.
+The modifier_list argument is a null-terminated string of the form
+``{@<emphasis remap='I'>category</emphasis>=<emphasis remap='I'>value</emphasis>}'', that is,
+having zero or more concatenated ``@<emphasis remap='I'>category</emphasis>=<emphasis remap='I'>value</emphasis>''
+entries, where <emphasis remap='I'>category</emphasis> is a category name
+and <emphasis remap='I'>value</emphasis> is the (possibly empty) setting for that category.
+The values are encoded in the current locale.
+Category names are restricted to the <acronym>POSIX</acronym> Portable Filename Character Set.
+</para>
+<para>
+<!-- .LP -->
+The local host X locale modifiers announcer (on <acronym>POSIX</acronym>-compliant systems,
+the XMODIFIERS environment variable) is appended to the modifier_list to
+provide default values on the local host.
+If a given category appears more than once in the list,
+the first setting in the list is used.
+If a given category is not included in the full modifier list,
+the category is set to an implementation-dependent default
+for the current locale.
+An empty value for a category explicitly specifies the
+implementation-dependent default.
+</para>
+<para>
+<!-- .LP -->
+If the function is successful, it returns a pointer to a string.
+The contents of the string are such that a subsequent call with that string
+(in the same locale) will restore the modifiers to the same settings.
+If modifier_list is a NULL pointer,
+<function>XSetLocaleModifiers</function>
+also returns a pointer to such a string,
+and the current locale modifiers are not changed.
+</para>
+<para>
+<!-- .LP -->
+If invalid values are given for one or more modifier categories supported by
+the locale, a NULL pointer is returned, and none of the
+current modifiers are changed.
+</para>
+<para>
+<!-- .LP -->
+At program startup,
+the modifiers that are in effect are unspecified until
+the first successful call to set them. Whenever the locale is changed, the
+modifiers that are in effect become unspecified until the next successful call
+to set them.
+Clients should always call
+<function>XSetLocaleModifiers</function>
+with a non-NULL modifier_list after setting the locale
+before they call any locale-dependent Xlib routine.
+</para>
+<para>
+<!-- .LP -->
+The only standard modifier category currently defined is ``im'',
+which identifies the desired input method.
+The values for input method are not standardized.
+A single locale may use multiple input methods,
+switching input method under user control.
+The modifier may specify the initial input method in effect
+or an ordered list of input methods.
+Multiple input methods may be specified in a single im value string
+in an implementation-dependent manner.
+</para>
+<para>
+<!-- .LP -->
+The returned modifiers string is owned by Xlib and should not be modified or
+freed by the client.
+It may be freed by Xlib after the current locale or modifiers are changed.
+Until freed, it will not be modified by Xlib.
+</para>
+<para>
+<!-- .LP -->
+The recommended procedure for clients initializing their locale and modifiers
+is to obtain locale and modifier announcers separately from
+one of the following prioritized sources:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+A command line option
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A resource
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The empty string ("")
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The first of these that is defined should be used.
+Note that when a locale command line option or locale resource is defined,
+the effect should be to set all categories to the specified locale,
+overriding any category-specific settings in the local host environment.
+</para>
+</sect1>
+<sect1 id="Locale_and_Modifier_Dependencies">
+<title>Locale and Modifier Dependencies</title>
+<!-- .XS -->
+<!-- (SN Locale and Modifier Dependencies -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The internationalized Xlib functions operate in the current locale
+configured by the host environment and X locale modifiers set by
+<function>XSetLocaleModifiers</function>
+or in the locale and modifiers configured at the time
+some object supplied to the function was created.
+For each locale-dependent function,
+the following table describes the locale (and modifiers) dependency:
+</para>
+
+<informaltable>
+ <tgroup cols='3' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <colspec colname='c3'/>
+ <thead>
+ <row>
+ <entry>Locale from</entry>
+ <entry>Affects the Function</entry>
+ <entry>In</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry></entry>
+ <entry>Locale Query/Configuration:</entry>
+ </row>
+ <row>
+ <entry><function>setlocale</function></entry>
+ <entry><function>XSupportsLocale</function></entry>
+ <entry>Locale queried</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XSetLocaleModifiers</function></entry>
+ <entry>Locale modified</entry>
+ </row>
+ <row>
+ <entry></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>Resources:</entry>
+ </row>
+ <row>
+ <entry><function>setlocale</function></entry>
+ <entry><function>XrmGetFileDatabase</function></entry>
+ <entry>Locale of <type>XrmDatabase</type></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XrmGetStringDatabase</function></entry>
+ </row>
+ <row>
+ <entry><type>XrmDatabase</type></entry>
+ <entry><function>XrmPutFileDatabase</function></entry>
+ <entry>Locale of <type>XrmDatabase</type></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XrmLocaleOfDatabase</function></entry>
+ </row>
+ <row>
+ <entry></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>Setting Standard Properties:</entry>
+ </row>
+ <row>
+ <entry><function>setlocale</function></entry>
+ <entry><function>XmbSetWMProperties</function></entry>
+ <entry>Encoding of supplied/returned
+ text (some WM_ property
+ text in environment locale)</entry>
+ </row>
+ <row>
+ <entry><function>setlocale</function></entry>
+ <entry><function>XmbTextPropertyToTextList</function></entry>
+ <entry>Encoding of supplied/returned text</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XwcTextPropertyToTextList</function></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XmbTextListToTextProperty</function></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XwcTextListToTextProperty</function></entry>
+ </row>
+ <row>
+ <entry></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>Text Input:</entry>
+ </row>
+ <row>
+ <entry><function>setlocale</function></entry>
+ <entry><function>XOpenIM</function></entry>
+ <entry><acronym>XIM</acronym> input method selection</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XRegisterIMInstantiateCallback</function></entry>
+ <entry><acronym>XIM</acronym> selection</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XUnregisterIMInstantiateCallback</function></entry>
+ <entry><acronym>XIM</acronym> selection</entry>
+ </row>
+ <row>
+ <entry><type>XIM</type></entry>
+ <entry><function>XCreateIC</function></entry>
+ <entry><acronym>XIC</acronym> input method configuration</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XLocaleOfIM</function>, and so on</entry>
+ <entry>Queried locale</entry>
+ </row>
+ <row>
+ <entry><type>XIC</type></entry>
+ <entry><function>XmbLookupString</function></entry>
+ <entry>Keyboard layout</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XwcLookupString</function></entry>
+ <entry>Encoding of returned text</entry>
+ </row>
+ <row>
+ <entry></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>Text Drawing:</entry>
+ </row>
+ <row>
+ <entry><function>setlocale</function></entry>
+ <entry><function>XOpenOM</function></entry>
+ <entry><acronym>XOM</acronym> output method selection</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XCreateFontSet</function></entry>
+ <entry>Charsets of fonts in XFontSet</entry>
+ </row>
+ <row>
+ <entry><type>XOM</type></entry>
+ <entry><function>XCreateOC</function></entry>
+ <entry><acronym>XOC</acronym> output method configuration</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XLocaleOfOM</function>, and so on</entry>
+ <entry>Queried locale</entry>
+ </row>
+ <row>
+ <entry><type>XFontSet</type></entry>
+ <entry><function>XmbDrawText</function>,</entry>
+ <entry>Locale of supplied text</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XwcDrawText</function>, and so on</entry>
+ <entry>Locale of supplied text</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XExtentsOfFontSet</function>, and so on</entry>
+ <entry>Locale-dependent metrics</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XmbTextExtents</function>,</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XwcTextExtents</function>, and so on</entry>
+ </row>
+ <row>
+ <entry></entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry>Xlib Errors:</entry>
+ </row>
+ <row>
+ <entry><function>setlocale</function></entry>
+ <entry><function>XGetErrorDatabaseText</function></entry>
+ <entry>Locale of error message</entry>
+ </row>
+ <row>
+ <entry></entry>
+ <entry><function>XGetErrorText</function></entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+Clients may assume that a locale-encoded text string returned
+by an X function can be passed to a C library routine, or vice versa,
+if the locale is the same at the two calls.
+</para>
+<para>
+<!-- .LP -->
+All text strings processed by internationalized Xlib functions are assumed
+to begin in the initial state of the encoding of the locale, if the encoding
+is state-dependent.
+</para>
+<para>
+<!-- .LP -->
+All Xlib functions behave as if they do not change the current locale
+or X modifier setting.
+(This means that if they do change locale or call
+<function>XSetLocaleModifiers</function>
+with a non-NULL argument, they must save and restore the current state on
+entry and exit.)
+Also, Xlib functions on implementations that conform to the ANSI C library do
+not alter the global state associated with the ANSI C functions
+<function>mblen</function>,
+<function>mbtowc</function>,
+<function>wctomb</function>,
+and
+<function>strtok</function>.
+</para>
+</sect1>
+<sect1 id="Variable_Argument_Lists">
+<title>Variable Argument Lists</title>
+<!-- .XS -->
+<!-- (SN Variable Argument Lists -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Various functions in this chapter have arguments that conform
+to the ANSI C variable argument list calling convention.
+Each function denoted with an argument of the form ``...'' takes
+a variable-length list of name and value pairs,
+where each name is a string and each value is of type
+<type>XPointer</type>.
+A name argument that is NULL identifies the end of the list.
+</para>
+<para>
+<!-- .LP -->
+A variable-length argument list may contain a nested list.
+If the name
+<symbol>XNVaNestedList</symbol>
+is specified in place of an argument name,
+then the following value is interpreted as an
+<type>XVaNestedList</type>
+value that specifies a list of values logically inserted into the
+original list at the point of declaration.
+A NULL identifies the end of a nested list.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To allocate a nested variable argument list dynamically, use
+<function>XVaCreateNestedList</function>.
+<indexterm significance="preferred"><primary>XVaCreateNestedList</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xvacreatenestedlist'>
+<funcprototype>
+ <funcdef>XVaNestedList <function>XVaCreateNestedList</function></funcdef>
+ <paramdef>int<parameter> dummy</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dummy</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an unused argument (required by ANSI C).
+<!-- .ds Al -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ ...
+ </term>
+ <listitem>
+ <para>
+Specifies the variable length argument list(Al.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XVaCreateNestedList</function>
+function allocates memory and copies its arguments into
+a single list pointer,
+which may be used as a value for arguments requiring a list value.
+Any entries are copied as specified.
+Data passed by reference is not copied;
+the caller must ensure data remains valid for the lifetime
+of the nested list.
+The list should be freed using
+<function>XFree</function>
+when it is no longer needed.
+</para>
+</sect1>
+<sect1 id="Output_Methods">
+<title>Output Methods</title>
+<!-- .XS -->
+<!-- (SN Output Methods -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This section provides discussions of the following X Output Method
+(<acronym>XOM</acronym>) topics:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Output method overview
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Output method functions
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Output method values
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Output context functions
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Output context values
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Creating and freeing a font set
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Obtaining font set metrics
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Drawing text using font sets
+ </para>
+ </listitem>
+</itemizedlist>
+<sect2 id="Output_Method_Overview">
+<title>Output Method Overview</title>
+<!-- .XS -->
+<!-- (SN Output Method Overview -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Locale-dependent text may include one or more text components, each of
+which may require different fonts and character set encodings.
+In some languages, each component might have a different
+drawing direction, and some components might contain
+context-dependent characters that change shape based on
+relationships with neighboring characters.
+</para>
+<para>
+<!-- .LP -->
+When drawing such locale-dependent text, some locale-specific
+knowledge is required;
+for example, what fonts are required to draw the text,
+how the text can be separated into components, and which
+fonts are selected to draw each component.
+Further, when bidirectional text must be drawn,
+the internal representation order of the text must be changed
+into the visual representation order to be drawn.
+</para>
+<para>
+<!-- .LP -->
+An X Output Method provides a functional interface so that clients
+do not have to deal directly with such locale-dependent details.
+Output methods provide the following capabilities:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Creating a set of fonts required to draw locale-dependent text.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Drawing locale-dependent text with a font set without the caller
+needing to be aware of locale dependencies.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Obtaining the escapement and extents in pixels of locale-dependent text.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Determining if bidirectional or context-dependent drawing is required
+in a specific locale with a specific font set.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Two different abstractions are used in the representation of
+the output method for clients.
+</para>
+<para>
+<!-- .LP -->
+The abstraction used to communicate with an output method
+is an opaque data structure represented by the
+<type>XOM</type>
+data type.
+The abstraction for representing the state of a particular output thread
+is called an <emphasis remap='I'>output context</emphasis>.
+The Xlib representation of an output context is an
+<type>XOC</type>,
+which is compatible with
+<type>XFontSet</type>
+in terms of its functional interface, but is
+a broader, more generalized abstraction.
+</para>
+</sect2>
+<sect2 id="Output_Method_Functions">
+<title>Output Method Functions</title>
+<!-- .XS -->
+<!-- (SN Output Method Functions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To open an output method, use
+<function>XOpenOM</function>.
+<indexterm significance="preferred"><primary>XOpenOM</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xopenom'>
+<funcprototype>
+ <funcdef>XOM <function>XOpenOM</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XrmDatabase<parameter> db</parameter></paramdef>
+ <paramdef>char<parameter> *res_name</parameter></paramdef>
+ <paramdef>char<parameter> *res_class</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>db</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a pointer to the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>res_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the full resource name of the application.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>res_class</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the full class name of the application.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XOpenOM</function>
+function opens an output method
+matching the current locale and modifiers specification.
+The current locale and modifiers are bound to the output method
+when
+<function>XOpenOM</function>
+is called.
+The locale associated with an output method cannot be changed.
+</para>
+<para>
+<!-- .LP -->
+The specific output method to which this call will be routed
+is identified on the basis of the current locale and modifiers.
+<function>XOpenOM</function>
+will identify a default output method corresponding to the
+current locale.
+That default can be modified using
+<function>XSetLocaleModifiers</function>
+to set the output method modifier.
+</para>
+<para>
+<!-- .LP -->
+The db argument is the resource database to be used by the output method
+for looking up resources that are private to the output method.
+It is not intended that this database be used to look
+up values that can be set as OC values in an output context.
+If db is NULL,
+no database is passed to the output method.
+</para>
+<para>
+<!-- .LP -->
+The res_name and res_class arguments specify the resource name
+and class of the application.
+They are intended to be used as prefixes by the output method
+when looking up resources that are common to all output contexts
+that may be created for this output method.
+The characters used for resource names and classes must be in the
+X Portable Character Set.
+The resources looked up are not fully specified
+if res_name or res_class is NULL.
+</para>
+<para>
+<!-- .LP -->
+The res_name and res_class arguments are not assumed to exist beyond
+the call to
+<function>XOpenOM</function>.
+The specified resource database is assumed to exist for the lifetime
+of the output method.
+</para>
+<para>
+<!-- .LP -->
+<function>XOpenOM</function>
+returns NULL if no output method could be opened.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To close an output method, use
+<function>XCloseOM</function>.
+<indexterm significance="preferred"><primary>XCloseOM</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcloseom'>
+<funcprototype>
+ <funcdef>Status <function>XCloseOM</function></funcdef>
+ <paramdef>XOM<parameter> om</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>om</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the output method.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCloseOM</function>
+function closes the specified output method.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set output method attributes, use
+<function>XSetOMValues</function>.
+<indexterm significance="preferred"><primary>XSetOMValues</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetomvalues'>
+<funcprototype>
+ <funcdef>char *<function>XSetOMValues</function></funcdef>
+ <paramdef>XOM<parameter> om</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>om</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the output method.
+<!-- .ds Al \ to set <acronym>XOM</acronym> values -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ ...
+ </term>
+ <listitem>
+ <para>
+Specifies the variable-length argument list(Al.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetOMValues</function>
+function presents a variable argument list programming interface
+for setting properties or features of the specified output method.
+This function returns NULL if it succeeds;
+otherwise,
+it returns the name of the first argument that could not be obtained.
+</para>
+<para>
+<!-- .LP -->
+No standard arguments are currently defined by Xlib.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To query an output method, use
+<function>XGetOMValues</function>.
+<indexterm significance="preferred"><primary>XGetOMValues</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetomvalues'>
+<funcprototype>
+ <funcdef>char *<function>XGetOMValues</function></funcdef>
+ <paramdef>XOM<parameter> om</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>om</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the output method.
+<!-- .ds Al \ to get XOM values -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ ...
+ </term>
+ <listitem>
+ <para>
+Specifies the variable-length argument list(Al.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetOMValues</function>
+function presents a variable argument list programming interface
+for querying properties or features of the specified output method.
+This function returns NULL if it succeeds;
+otherwise,
+it returns the name of the first argument that could not be obtained.
+</para>
+<para>
+<!-- .LP -->
+To obtain the display associated with an output method, use
+<function>XDisplayOfOM</function>.
+<indexterm significance="preferred"><primary>XDisplayOfOM</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdisplayofom'>
+<funcprototype>
+ <funcdef>Display *<function>XDisplayOfOM</function></funcdef>
+ <paramdef>XOM<parameter> om</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>om</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the output method.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDisplayOfOM</function>
+function returns the display associated with the specified output method.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To get the locale associated with an output method, use
+<function>XLocaleOfOM</function>.
+<indexterm significance="preferred"><primary>XLocaleOfOM</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xlocaleofom'>
+<funcprototype>
+ <funcdef>char *<function>XLocaleOfOM</function></funcdef>
+ <paramdef>XOM<parameter> om</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>om</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the output method.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XLocaleOfOM</function>
+returns the locale associated with the specified output method.
+</para>
+</sect2>
+<sect2 id="X_Output_Method_Values">
+<title>X Output Method Values</title>
+<!-- .XS -->
+<!-- (SN X Output Method Values -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The following table describes how <acronym>XOM</acronym> values are interpreted by an
+output method.
+The first column lists the <acronym>XOM</acronym> values. The second column indicates
+how each of the <acronym>XOM</acronym> values are treated by a particular output style.
+</para>
+<para>
+<!-- .LP -->
+</para>
+<para>
+<!-- .LP -->
+The following key applies to this table.
+</para>
+
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <thead>
+ <row>
+ <entry>Key</entry>
+ <entry>Explanation</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>G</entry>
+ <entry>This value may be read using <function>XGetOMValues</function>.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <thead>
+ <row>
+ <entry><acronym>XOM</acronym> Value</entry>
+ <entry>Key</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><symbol>XNRequiredCharSet</symbol></entry>
+ <entry>G</entry>
+ </row>
+ <row>
+ <entry><symbol>XNQueryOrientation</symbol></entry>
+ <entry>G</entry>
+ </row>
+ <row>
+ <entry><symbol>XNDirectionalDependentDrawing</symbol></entry>
+ <entry>G</entry>
+ </row>
+ <row>
+ <entry><symbol>XNContextualDrawing</symbol></entry>
+ <entry>G</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+</para>
+<sect3 id="Required_Char_Set">
+<title>Required Char Set</title>
+<!-- .XS -->
+<!-- (SN Required Char Set -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNRequiredCharSet</symbol>
+argument returns the list of charsets that are required for loading the fonts
+needed for the locale.
+The value of the argument is a pointer to a structure of type
+<structname>XOMCharSetList</structname>.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XOMCharSetList</structname>
+structure is defined as follows:
+<indexterm significance="preferred"><primary>XOMCharSetList</primary></indexterm>
+<!-- .sM -->
+</para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ int charset_count;
+ char **charset_list;
+} XOMCharSetList;
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The charset_list member is a list of one or more null-terminated
+charset names, and the charset_count member is the number of
+charset names.
+</para>
+<para>
+<!-- .LP -->
+The required charset list is owned by Xlib and should not be modified or
+freed by the client.
+It will be freed by a call to
+<function>XCloseOM</function>
+with the associated
+<type>XOM</type>.
+Until freed, its contents will not be modified by Xlib.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+<sect3 id="Query_Orientation">
+<title>Query Orientation</title>
+<!-- .XS -->
+<!-- (SN Query Orientation -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNQueryOrientation</symbol>
+argument returns the global orientation of text when drawn.
+Other than
+<constant>XOMOrientation_LTR_TTB</constant>,
+the set of orientations supported is locale-dependent.
+The value of the argument is a pointer to a structure of type
+<structname>XOMOrientation</structname>.
+Clients are responsible for freeing the
+<structname>XOMOrientation</structname>
+structure by using
+<function>XFree</function>;
+this also frees the contents of the structure.
+</para>
+
+<!-- .LP -->
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ int num_orientation;
+ XOrientation *orientation; /* Input Text description */
+} XOMOrientation;
+
+typedef enum {
+ XOMOrientation_LTR_TTB,
+ XOMOrientation_RTL_TTB,
+ XOMOrientation_TTB_LTR,
+ XOMOrientation_TTB_RTL,
+ XOMOrientation_Context
+} XOrientation;
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The possible value for XOrientation may be:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+<constant>XOMOrientation_LTR_TTB</constant>
+left-to-right, top-to-bottom global orientation
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<constant>XOMOrientation_RTL_TTB</constant>
+right-to-left, top-to-bottom global orientation
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<constant>XOMOrientation_TTB_LTR</constant>
+top-to-bottom, left-to-right global orientation
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<constant>XOMOrientation_TTB_RTL</constant>
+top-to-bottom, right-to-left global orientation
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<constant>XOMOrientation_Context</constant>
+contextual global orientation
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+<sect3 id="Directional_Dependent_Drawing">
+<title>Directional Dependent Drawing</title>
+<!-- .XS -->
+<!-- (SN Directional Dependent Drawing -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNDirectionalDependentDrawing</symbol>
+argument indicates whether the text rendering functions
+implement implicit handling of directional text. If this value
+is
+<symbol>True</symbol>,
+the output method has knowledge of directional
+dependencies and reorders text as necessary when
+rendering text. If this value is
+<symbol>False</symbol>,
+the output method does not implement any directional text
+handling, and all character directions are assumed to be left-to-right.
+</para>
+<para>
+<!-- .LP -->
+Regardless of the rendering order of characters,
+the origins of all characters are on the primary draw direction side
+of the drawing origin.
+</para>
+<para>
+<!-- .LP -->
+This OM value presents functionality identical to the
+<function>XDirectionalDependentDrawing</function>
+function.
+</para>
+</sect3>
+<sect3 id="Context_Dependent_Drawing">
+<title>Context Dependent Drawing</title>
+<!-- .XS -->
+<!-- (SN Context Dependent Drawing -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNContextualDrawing</symbol>
+argument indicates whether the text rendering functions
+implement implicit context-dependent drawing. If this value is
+<symbol>True</symbol>,
+the output method has knowledge of context dependencies and
+performs character shape editing, combining glyphs to present
+a single character as necessary. The actual shape editing is
+dependent on the locale implementation and the font set used.
+</para>
+<para>
+<!-- .LP -->
+This OM value presents functionality identical to the
+<function>XContextualDrawing</function>
+function.
+</para>
+</sect3>
+</sect2>
+<sect2 id="Output_Context_Functions">
+<title>Output Context Functions</title>
+<!-- .XS -->
+<!-- (SN Output Context Functions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+An output context is an abstraction that contains both the data
+required by an output method and the information required
+to display that data.
+There can be multiple output contexts for one output method.
+The programming interfaces for creating, reading, or modifying
+an output context use a variable argument list.
+The name elements of the argument lists are referred to as <acronym>XOC</acronym> values.
+It is intended that output methods be controlled by these <acronym>XOC</acronym> values.
+As new <acronym>XOC</acronym> values are created,
+they should be registered with the X Consortium.
+An
+<type>XOC</type>
+can be used anywhere an
+<type>XFontSet</type>
+can be used, and vice versa;
+<type>XFontSet</type>
+is retained for compatibility with previous releases.
+The concepts of output methods and output contexts include broader,
+more generalized abstraction than font set,
+supporting complex and more intelligent text display, and dealing not only
+with multiple fonts but also with context dependencies.
+However,
+<type>XFontSet</type>
+is widely used in several interfaces, so
+<type>XOC</type>
+is defined as an upward compatible type of
+<type>XFontSet</type>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create an output context, use
+<function>XCreateOC</function>.
+<indexterm significance="preferred"><primary>XCreateOC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreateoc'>
+<funcprototype>
+ <funcdef>XOC <function>XCreateOC</function></funcdef>
+ <paramdef>XOM<parameter> om</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>om</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the output method.
+<!-- .ds Al \ to set <acronym>XOC</acronym> values -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ ...
+ </term>
+ <listitem>
+ <para>
+Specifies the variable-length argument list(Al.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreateOC</function>
+function creates an output context within the specified output method.
+</para>
+<para>
+<!-- .LP -->
+The base font names argument is mandatory at creation time, and
+the output context will not be created unless it is provided.
+All other output context values can be set later.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreateOC</function>
+returns NULL if no output context could be created.
+NULL can be returned for any of the following reasons:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+A required argument was not set.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A read-only argument was set.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+An argument name is not recognized.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The output method encountered an output method implementation-dependent error.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+<function>XCreateOC</function>
+can generate a
+<errorname>BadAtom</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To destroy an output context, use
+<function>XDestroyOC</function>.
+<indexterm significance="preferred"><primary>XDestroyOC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdestroyoc'>
+<funcprototype>
+ <funcdef>void <function>XDestroyOC</function></funcdef>
+ <paramdef>XOC<parameter> oc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>oc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the output context.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDestroyOC</function>
+function destroys the specified output context.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To get the output method associated with an output context, use
+<function>XOMOfOC</function>.
+<indexterm significance="preferred"><primary>XOMOfOC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xomofoc'>
+<funcprototype>
+ <funcdef>XOM <function>XOMOfOC</function></funcdef>
+ <paramdef>XOC<parameter> oc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>oc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the output context.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XOMOfOC</function>
+function returns the output method associated with the
+specified output context.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+Xlib provides two functions for setting and reading output context values,
+respectively,
+<function>XSetOCValues</function>
+and
+<function>XGetOCValues</function>.
+Both functions have a variable-length argument list.
+In that argument list, any <acronym>XOC</acronym> value's name must be denoted
+with a character string using the X Portable Character Set.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set <acronym>XOC</acronym> values, use
+<function>XSetOCValues</function>.
+<indexterm significance="preferred"><primary>XSetOCValues</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetocvalues'>
+<funcprototype>
+ <funcdef>char *<function>XSetOCValues</function></funcdef>
+ <paramdef>XOC<parameter> oc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>oc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the output context.
+<!-- .ds Al \ to set <acronym>XOC</acronym> values -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ ...
+ </term>
+ <listitem>
+ <para>
+Specifies the variable-length argument list(Al.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetOCValues</function>
+function returns NULL if no error occurred;
+otherwise,
+it returns the name of the first argument that could not be set.
+An argument might not be set for any of the following reasons:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The argument is read-only.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The argument name is not recognized.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+An implementation-dependent error occurs.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Each value to be set must be an appropriate datum,
+matching the data type imposed by the semantics of the argument.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetOCValues</function>
+can generate a
+<errorname>BadAtom</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain <acronym>XOC</acronym> values, use
+<function>XGetOCValues</function>.
+<indexterm significance="preferred"><primary>XGetOCValues</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetocvalues'>
+<funcprototype>
+ <funcdef>char *<function>XGetOCValues</function></funcdef>
+ <paramdef>XOC<parameter> oc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>oc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the output context.
+<!-- .ds Al \ to get XOC values -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ ...
+ </term>
+ <listitem>
+ <para>
+Specifies the variable-length argument list(Al.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetOCValues</function>
+function returns NULL if no error occurred; otherwise,
+it returns the name of the first argument that could not be obtained.
+An argument might not be obtained for any of the following reasons:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The argument name is not recognized.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+An implementation-dependent error occurs.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Each argument value
+following a name must point to a location where the value is to be stored.
+</para>
+</sect2>
+
+<sect2 id="Output_Context_Values">
+<title>Output Context Values</title>
+<!-- .XS -->
+<!-- (SN Output Context Values -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The following table describes how <acronym>XOC</acronym> values are interpreted
+by an output method.
+The first column lists the <acronym>XOC</acronym> values.
+The second column indicates the alternative interfaces that function
+identically and are provided for compatibility with previous releases.
+The third column indicates how each of the <acronym>XOC</acronym> values is treated.
+</para>
+<!-- .LP -->
+<para>
+The following keys apply to this table.
+</para>
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <thead>
+ <row>
+ <entry>Key</entry>
+ <entry>Explanation</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>C</entry>
+ <entry>This value must be set with <function>XCreateOC</function>.</entry>
+ </row>
+ <row>
+ <entry>D</entry>
+ <entry>This value may be set using <function>XCreateOC</function>.
+ If it is not set,a default is provided.</entry>
+ </row>
+ <row>
+ <entry>G</entry>
+ <entry>This value may be read using <function>XGetOCValues</function>.</entry>
+ </row>
+ <row>
+ <entry>S</entry>
+ <entry>This value must be set using <function>XSetOCValues</function>.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<!-- .LP -->
+<informaltable>
+ <tgroup cols='3' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <colspec colname='c3'/>
+ <thead>
+ <row>
+ <entry><acronym>XOC</acronym> Value</entry>
+ <entry>Alternative Interface</entry>
+ <entry>Key</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>BaseFontName</entry>
+ <entry><function>XCreateFontSet</function></entry>
+ <entry>C-G</entry>
+ </row>
+ <row>
+ <entry>MissingCharSet</entry>
+ <entry><function>XCreateFontSet</function></entry>
+ <entry>G</entry>
+ </row>
+ <row>
+ <entry>DefaultString</entry>
+ <entry><function>XCreateFontSet</function></entry>
+ <entry>G</entry>
+ </row>
+ <row>
+ <entry>Orientation</entry>
+ <entry>-</entry>
+ <entry>D-S-G</entry>
+ </row>
+ <row>
+ <entry>ResourceName</entry>
+ <entry>-</entry>
+ <entry>S-G</entry>
+ </row>
+ <row>
+ <entry>ResourceClass</entry>
+ <entry>-</entry>
+ <entry>S-G</entry>
+ </row>
+ <row>
+ <entry>FontInfo</entry>
+ <entry><function>XFontsOfFontSet</function></entry>
+ <entry>G</entry>
+ </row>
+ <row>
+ <entry>OMAutomatic</entry>
+ <entry>-</entry>
+ <entry>G</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+</para>
+<sect3 id="Base_Font_Name">
+<title>Base Font Name</title>
+<!-- .XS -->
+<!-- (SN Base Font Name -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNBaseFontName</symbol>
+argument is a list of base font names that Xlib uses
+to load the fonts needed for the locale.
+The base font names are a comma-separated list. The string is null-terminated
+and is assumed to be in the Host Portable Character Encoding;
+otherwise, the result is implementation-dependent.
+White space immediately on either side of a separating comma is ignored.
+</para>
+<para>
+<!-- .LP -->
+Use of <acronym>XLFD</acronym> font names permits Xlib to obtain the fonts needed for a
+variety of locales from a single locale-independent base font name.
+The single base font name should name a family of fonts whose members
+are encoded in the various charsets needed by the locales of interest.
+</para>
+<para>
+<!-- .LP -->
+An <acronym>XLFD</acronym> base font name can explicitly name a charset needed for the locale.
+This allows the user to specify an exact font for use with a charset required
+by a locale, fully controlling the font selection.
+</para>
+<para>
+<!-- .LP -->
+If a base font name is not an <acronym>XLFD</acronym> name,
+Xlib will attempt to obtain an <acronym>XLFD</acronym> name from the font properties
+for the font.
+If Xlib is successful, the
+<function>XGetOCValues</function>
+function will return this <acronym>XLFD</acronym> name instead of the client-supplied name.
+</para>
+<para>
+<!-- .LP -->
+This argument must be set at creation time
+and cannot be changed.
+If no fonts exist for any of the required charsets,
+or if the locale definition in Xlib requires that a font exist
+for a particular charset and a font is not found for that charset,
+<function>XCreateOC</function>
+returns NULL.
+</para>
+<para>
+<!-- .LP -->
+When querying for the
+<symbol>XNBaseFontName</symbol>
+<acronym>XOC</acronym> value,
+<function>XGetOCValues</function>
+returns a null-terminated string identifying the base font names that
+Xlib used to load the fonts needed for the locale.
+This string is owned by Xlib and should not be modified or freed by
+the client.
+The string will be freed by a call to
+<function>XDestroyOC</function>
+with the associated
+<type>XOC</type>.
+Until freed, the string contents will not be modified by Xlib.
+</para>
+</sect3>
+<sect3 id="Missing_CharSet">
+<title>Missing CharSet</title>
+<!-- .XS -->
+<!-- (SN Missing CharSet -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNMissingCharSet</symbol>
+argument returns the list of required charsets that are missing from the
+font set.
+The value of the argument is a pointer to a structure of type
+<structname>XOMCharSetList</structname>.
+</para>
+<para>
+<!-- .LP -->
+If fonts exist for all of the charsets required by the current locale,
+charset_list is set to NULL and charset_count is set to zero.
+If no fonts exist for one or more of the required charsets,
+charset_list is set to a list of one or more null-terminated charset names
+for which no fonts exist, and charset_count is set to the number of
+missing charsets.
+The charsets are from the list of the required charsets for
+the encoding of the locale and do not include any charsets to which Xlib
+may be able to remap a required charset.
+</para>
+<para>
+<!-- .LP -->
+The missing charset list is owned by Xlib and should not be modified or
+freed by the client.
+It will be freed by a call to
+<function>XDestroyOC</function>
+with the associated
+<type>XOC</type>.
+Until freed, its contents will not be modified by Xlib.
+</para>
+</sect3>
+<sect3 id="Default_String">
+<title>Default String</title>
+<!-- .XS -->
+<!-- (SN Default String -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+When a drawing or measuring function is called with an
+<type>XOC</type>
+that has missing charsets, some characters in the locale will not be
+drawable.
+The
+<symbol>XNDefaultString</symbol>
+argument returns a pointer to a string that represents the glyphs
+that are drawn with this
+<type>XOC</type>
+when the charsets of the available fonts do not include all glyphs
+required to draw a character.
+The string does not necessarily consist of valid characters
+in the current locale and is not necessarily drawn with
+the fonts loaded for the font set,
+but the client can draw or measure the default glyphs
+by including this string in a string being drawn or measured with the
+<type>XOC</type>.
+</para>
+<para>
+<!-- .LP -->
+If the
+<symbol>XNDefaultString</symbol>
+argument returned the empty string (""),
+no glyphs are drawn and the escapement is zero.
+The returned string is null-terminated.
+It is owned by Xlib and should not be modified or freed by the client.
+It will be freed by a call to
+<function>XDestroyOC</function>
+with the associated
+<type>XOC</type>.
+Until freed, its contents will not be modified by Xlib.
+</para>
+</sect3>
+<sect3 id="Orientation">
+<title>Orientation</title>
+<!-- .XS -->
+<!-- (SN Orientation -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNOrientation</symbol>
+argument specifies the current orientation of text when drawn. The value of
+this argument is one of the values returned by the
+<function>XGetOMValues</function>
+function with the
+<symbol>XNQueryOrientation</symbol>
+argument specified in the
+<type>XOrientation</type>
+list.
+The value of the argument is of type
+<type>XOrientation</type>.
+When
+<symbol>XNOrientation</symbol>
+is queried, the value specifies the current orientation.
+When
+<symbol>XNOrientation</symbol>
+is set, a value is used to set the current orientation.
+</para>
+<para>
+<!-- .LP -->
+When
+<constant>XOMOrientation_Context</constant>
+is set, the text orientation of the
+text is determined according to an implementation-defined method
+(for example, ISO 6429 control sequences), and the initial text orientation for
+locale-dependent Xlib functions is assumed to
+be
+<constant>XOMOrientation_LTR_TTB</constant>.
+</para>
+<para>
+<!-- .LP -->
+The
+<symbol>XNOrientation</symbol>
+value does not change the prime drawing direction
+for Xlib drawing functions.
+</para>
+</sect3>
+<sect3 id="Resource_Name_and_Class">
+<title>Resource Name and Class</title>
+<!-- .XS -->
+<!-- (SN Resource Name and Class -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNResourceName</symbol>
+and
+<symbol>XNResourceClass</symbol>
+arguments are strings that specify the full name and class
+used by the client to obtain resources for the display of the output context.
+These values should be used as prefixes for name and class
+when looking up resources that may vary according to the output context.
+If these values are not set,
+the resources will not be fully specified.
+</para>
+<para>
+<!-- .LP -->
+It is not intended that values that can be set as <acronym>XOM</acronym> values be
+set as resources.
+</para>
+<para>
+<!-- .LP -->
+When querying for the
+<symbol>XNResourceName</symbol>
+or
+<symbol>XNResourceClass</symbol>
+<acronym>XOC</acronym> value,
+<function>XGetOCValues</function>
+returns a null-terminated string.
+This string is owned by Xlib and should not be modified or freed by
+the client.
+The string will be freed by a call to
+<function>XDestroyOC</function>
+with the associated
+<type>XOC</type>
+or when the associated value is changed via
+<function>XSetOCValues</function>.
+Until freed, the string contents will not be modified by Xlib.
+</para>
+</sect3>
+<sect3 id="Font_Info">
+<title>Font Info</title>
+<!-- .XS -->
+<!-- (SN Font Info -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNFontInfo</symbol>
+argument specifies a list of one or more
+<structname>XFontStruct</structname>
+structures
+and font names for the fonts used for drawing by the given output context.
+The value of the argument is a pointer to a structure of type
+<structname>XOMFontInfo</structname>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ int num_font;
+ XFontStruct **font_struct_list;
+ char **font_name_list;
+} XOMFontInfo;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+A list of pointers to the
+<structname>XFontStruct</structname>
+structures is returned to font_struct_list.
+A list of pointers to null-terminated, fully-specified font name strings
+in the locale of the output context is returned to font_name_list.
+The font_name_list order corresponds to the font_struct_list order.
+The number of
+<structname>XFontStruct</structname>
+structures and font names is returned to num_font.
+</para>
+<para>
+<!-- .LP -->
+Because it is not guaranteed that a given character will be imaged using a
+single font glyph,
+there is no provision for mapping a character or default string
+to the font properties, font ID, or direction hint for the font
+for the character.
+The client may access the
+<structname>XFontStruct</structname>
+list to obtain these values for all the fonts currently in use.
+</para>
+<para>
+<!-- .LP -->
+Xlib does not guarantee that fonts are loaded from the server
+at the creation of an
+<type>XOC</type>.
+Xlib may choose to cache font data, loading it only as needed to draw text
+or compute text dimensions.
+Therefore, existence of the per_char metrics in the
+<structname>XFontStruct</structname>
+structures in the
+<structname>XFontStructSet</structname>
+is undefined.
+Also, note that all properties in the
+<structname>XFontStruct</structname>
+structures are in the STRING encoding.
+</para>
+<para>
+<!-- .LP -->
+The client must not free the
+<structname>XOMFontInfo</structname>
+struct itself; it will be freed when the
+<type>XOC</type>
+is closed.
+</para>
+</sect3>
+<sect3 id="OM_Automatic">
+<title>OM Automatic</title>
+<!-- .XS -->
+<!-- (SN OM Automatic -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNOMAutomatic</symbol>
+argument returns whether the associated output context was created by
+<function>XCreateFontSet</function>
+or not. Because the
+<function>XFreeFontSet</function>
+function not only destroys the output context but also closes the implicit
+output method associated with it,
+<function>XFreeFontSet</function>
+should be used with any output context created by
+<function>XCreateFontSet</function>.
+However, it is possible that a client does not know how the output context
+was created.
+Before a client destroys the output context,
+it can query whether
+<symbol>XNOMAutomatic</symbol>
+is set to determine whether
+<function>XFreeFontSet</function>
+or
+<function>XDestroyOC</function>
+should be used to destroy the output context.
+</para>
+</sect3>
+</sect2>
+<sect2 id="Creating_and_Freeing_a_Font_Set">
+<title>Creating and Freeing a Font Set</title>
+<!-- .XS -->
+<!-- (SN Creating and Freeing a Font Set -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib international text drawing is done using a set of one or more fonts,
+as needed for the locale of the text.
+Fonts are loaded according to a list of base font names
+supplied by the client and the charsets required by the locale.
+The
+<type>XFontSet</type>
+is an opaque type representing the state of a particular output thread
+and is equivalent to the type
+<type>XOC</type>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+The
+<function>XCreateFontSet</function>
+function is a convenience function for creating an output context using
+only default values. The returned
+<type>XFontSet</type>
+has an implicitly created
+<type>XOM</type>.
+This
+<type>XOM</type>
+has an OM value
+<symbol>XNOMAutomatic</symbol>
+automatically set to
+<symbol>True</symbol>
+so that the output context self indicates whether it was created by
+<function>XCreateOC</function>
+or
+<function>XCreateFontSet</function>.
+<indexterm significance="preferred"><primary>XCreateFontSet</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreatefontset'>
+<funcprototype>
+ <funcdef>XFontSet <function>XCreateFontSet</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *base_font_name_list</parameter></paramdef>
+ <paramdef>char<parameter> ***missing_charset_list_return</parameter></paramdef>
+ <paramdef>int<parameter> *missing_charset_count_return</parameter></paramdef>
+ <paramdef>char<parameter> **def_string_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>base_font_name_list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the base font names.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>missing_charset_list_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the missing charsets.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>missing_charset_count_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of missing charsets.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>def_string_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the string drawn for missing charsets.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreateFontSet</function>
+function creates a font set for the specified display.
+The font set is bound to the current locale when
+<function>XCreateFontSet</function>
+is called.
+The font set may be used in subsequent calls to obtain font
+and character information and to image text in the locale of the font set.
+</para>
+<para>
+<!-- .LP -->
+The base_font_name_list argument is a list of base font names
+that Xlib uses to load the fonts needed for the locale.
+The base font names are a comma-separated list.
+The string is null-terminated
+and is assumed to be in the Host Portable Character Encoding;
+otherwise, the result is implementation-dependent.
+White space immediately on either side of a separating comma is ignored.
+</para>
+<para>
+<!-- .LP -->
+Use of <acronym>XLFD</acronym> font names permits Xlib to obtain the fonts needed for a
+variety of locales from a single locale-independent base font name.
+The single base font name should name a family of fonts whose members
+are encoded in the various charsets needed by the locales of interest.
+</para>
+<para>
+<!-- .LP -->
+An <acronym>XLFD</acronym> base font name can explicitly name a charset needed for the locale.
+This allows the user to specify an exact font for use with a charset required
+by a locale, fully controlling the font selection.
+</para>
+<para>
+<!-- .LP -->
+If a base font name is not an <acronym>XLFD</acronym> name,
+Xlib will attempt to obtain an <acronym>XLFD</acronym> name from the font properties
+for the font.
+If this action is successful in obtaining an <acronym>XLFD</acronym> name, the
+<function>XBaseFontNameListOfFontSet</function>
+function will return this <acronym>XLFD</acronym> name instead of the client-supplied name.
+</para>
+<para>
+<!-- .LP -->
+Xlib uses the following algorithm to select the fonts
+that will be used to display text with the
+<type>XFontSet</type>.
+</para>
+<para>
+<!-- .LP -->
+For each font charset required by the locale,
+the base font name list is searched for the first appearance of one
+of the following cases that names a set of fonts that exist at the server:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The first <acronym>XLFD</acronym>-conforming base font name that specifies the required
+charset or a superset of the required charset in its
+<structfield>CharSetRegistry</structfield>
+and
+<structfield>CharSetEncoding</structfield>
+fields.
+The implementation may use a base font name whose specified charset
+is a superset of the required charset, for example,
+an ISO8859-1 font for an ASCII charset.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The first set of one or more <acronym>XLFD</acronym>-conforming base font names
+that specify one or more charsets that can be remapped to support the
+required charset.
+The Xlib implementation may recognize various mappings
+from a required charset to one or more other charsets
+and use the fonts for those charsets.
+For example, JIS Roman is ASCII with tilde and backslash replaced
+by yen and overbar;
+Xlib may load an ISO8859-1 font to support this character set
+if a JIS Roman font is not available.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The first <acronym>XLFD</acronym>-conforming font name or the first non-<acronym>XLFD</acronym> font name
+for which an <acronym>XLFD</acronym> font name can be obtained, combined with the
+required charset (replacing the
+<structfield>CharSetRegistry</structfield>
+and
+<structfield>CharSetEncoding</structfield>
+fields in the <acronym>XLFD</acronym> font name).
+As in case 1,
+the implementation may use a charset that is a superset
+of the required charset.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The first font name that can be mapped in some implementation-dependent
+manner to one or more fonts that support imaging text in the charset.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+For example, assume that a locale required the charsets:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+ISO8859-1
+JISX0208.1983
+JISX0201.1976
+GB2312-1980.0
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The user could supply a base_font_name_list that explicitly specifies the
+charsets, ensuring that specific fonts are used if they exist.
+For example:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+"-JIS-Fixed-Medium-R-Normal--26-180-100-100-C-240-JISX0208.1983-0,\\
+-JIS-Fixed-Medium-R-Normal--26-180-100-100-C-120-JISX0201.1976-0,\\
+-GB-Fixed-Medium-R-Normal--26-180-100-100-C-240-GB2312-1980.0,\\
+-Adobe-Courier-Bold-R-Normal--25-180-75-75-M-150-ISO8859-1"
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+Alternatively, the user could supply a base_font_name_list
+that omits the charsets,
+letting Xlib select font charsets required for the locale.
+For example:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+"-JIS-Fixed-Medium-R-Normal--26-180-100-100-C-240,\\
+-JIS-Fixed-Medium-R-Normal--26-180-100-100-C-120,\\
+-GB-Fixed-Medium-R-Normal--26-180-100-100-C-240,\\
+-Adobe-Courier-Bold-R-Normal--25-180-100-100-M-150"
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+Alternatively, the user could simply supply a single base font name
+that allows Xlib to select from all available fonts
+that meet certain minimum <acronym>XLFD</acronym> property requirements.
+For example:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+"-*-*-*-R-Normal--*-180-100-100-*-*"
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+If
+<function>XCreateFontSet</function>
+is unable to create the font set,
+either because there is insufficient memory or because the current locale
+is not supported,
+<function>XCreateFontSet</function>
+returns NULL, missing_charset_list_return is set to NULL,
+and missing_charset_count_return
+is set to zero.
+If fonts exist for all of the charsets required by the current locale,
+<function>XCreateFontSet</function>
+returns a valid
+<type>XFontSet</type>,
+missing_charset_list_return is set to NULL,
+and missing_charset_count_return is set to zero.
+</para>
+<para>
+<!-- .LP -->
+If no font exists for one or more of the required charsets,
+<function>XCreateFontSet</function>
+sets missing_charset_list_return to a
+list of one or more null-terminated charset names for which no font exists
+and sets missing_charset_count_return to the number of missing fonts.
+The charsets are from the list of the required charsets for
+the encoding of the locale and do not include any charsets to which Xlib
+may be able to remap a required charset.
+</para>
+<para>
+<!-- .LP -->
+If no font exists for any of the required charsets
+or if the locale definition in Xlib requires that a font exist
+for a particular charset and a font is not found for that charset,
+<function>XCreateFontSet</function>
+returns NULL.
+Otherwise,
+<function>XCreateFontSet</function>
+returns a valid
+<type>XFontSet</type>
+to font_set.
+</para>
+<para>
+<!-- .LP -->
+When an Xmb/wc drawing or measuring function is called with an
+<type>XFontSet</type>
+that has missing charsets, some characters in the locale will not be
+drawable.
+If def_string_return is non-NULL,
+<function>XCreateFontSet</function>
+returns a pointer to a string that represents the glyphs
+that are drawn with this
+<type>XFontSet</type>
+when the charsets of the available fonts do not include all font glyphs
+required to draw a codepoint.
+The string does not necessarily consist of valid characters
+in the current locale and is not necessarily drawn with
+the fonts loaded for the font set,
+but the client can draw and measure the default glyphs
+by including this string in a string being drawn or measured with the
+<type>XFontSet</type>.
+</para>
+<para>
+<!-- .LP -->
+If the string returned to def_string_return is the empty string (""),
+no glyphs are drawn, and the escapement is zero.
+The returned string is null-terminated.
+It is owned by Xlib and should not be modified or freed by the client.
+It will be freed by a call to
+<function>XFreeFontSet</function>
+with the associated
+<type>XFontSet</type>.
+Until freed, its contents will not be modified by Xlib.
+</para>
+<para>
+<!-- .LP -->
+The client is responsible for constructing an error message from the
+missing charset and default string information and may choose to continue
+operation in the case that some fonts did not exist.
+</para>
+<para>
+<!-- .LP -->
+The returned
+<type>XFontSet</type>
+and missing charset list should be freed with
+<function>XFreeFontSet</function>
+and
+<function>XFreeStringList</function>,
+respectively.
+The client-supplied base_font_name_list may be freed
+by the client after calling
+<function>XCreateFontSet</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain a list of
+<structname>XFontStruct</structname>
+structures and full font names given an
+<type>XFontSet</type>,
+use
+<function>XFontsOfFontSet</function>.
+<indexterm significance="preferred"><primary>XFontsOfFontSet</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfontsoffontset'>
+<funcprototype>
+ <funcdef>int <function>XFontsOfFontSet</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+ <paramdef>XFontStruct<parameter> ***font_struct_list_return</parameter></paramdef>
+ <paramdef>char<parameter> ***font_name_list_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_struct_list_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the list of font structs.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_name_list_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the list of font names.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFontsOfFontSet</function>
+function returns a list of one or more
+<structname>XFontStruct</structname>s
+and font names for the fonts used by the Xmb and Xwc layers
+for the given font set.
+A list of pointers to the
+<structname>XFontStruct</structname>
+structures is returned to font_struct_list_return.
+A list of pointers to null-terminated, fully specified font name strings
+in the locale of the font set is returned to font_name_list_return.
+The font_name_list order corresponds to the font_struct_list order.
+The number of
+<structname>XFontStruct</structname>
+structures and font names is returned as the value of the function.
+</para>
+<para>
+<!-- .LP -->
+Because it is not guaranteed that a given character will be imaged using a
+single font glyph,
+there is no provision for mapping a character or default string
+to the font properties, font ID, or direction hint for the font
+for the character.
+The client may access the
+<structname>XFontStruct</structname>
+list to obtain these values for all the fonts currently in use.
+</para>
+<para>
+<!-- .LP -->
+Xlib does not guarantee that fonts are loaded from the server
+at the creation of an
+<type>XFontSet</type>.
+Xlib may choose to cache font data, loading it only as needed to draw text
+or compute text dimensions.
+Therefore, existence of the per_char metrics in the
+<structname>XFontStruct</structname>
+structures in the
+<structname>XFontStructSet</structname>
+is undefined.
+Also, note that all properties in the
+<structname>XFontStruct</structname>
+structures are in the STRING encoding.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XFontStruct</structname>
+and font name lists are owned by Xlib
+and should not be modified or freed by the client.
+They will be freed by a call to
+<function>XFreeFontSet</function>
+with the associated
+<type>XFontSet</type>.
+Until freed, their contents will not be modified by Xlib.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the base font name list and the selected font name list given an
+<type>XFontSet</type>,
+use
+<function>XBaseFontNameListOfFontSet</function>.
+<indexterm significance="preferred"><primary>XBaseFontNameListOfFontSet</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xbasefontnamelistoffontset'>
+<funcprototype>
+ <funcdef>char *<function>XBaseFontNameListOfFontSet</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XBaseFontNameListOfFontSet</function>
+function returns the original base font name list supplied
+by the client when the
+<type>XFontSet</type>
+was created.
+A null-terminated string containing a list of
+comma-separated font names is returned
+as the value of the function.
+White space may appear immediately on either side of separating commas.
+</para>
+<para>
+<!-- .LP -->
+If
+<function>XCreateFontSet</function>
+obtained an <acronym>XLFD</acronym> name from the font properties for the font specified
+by a non-<acronym>XLFD</acronym> base name, the
+<function>XBaseFontNameListOfFontSet</function>
+function will return the <acronym>XLFD</acronym> name instead of the non-<acronym>XLFD</acronym> base name.
+</para>
+<para>
+<!-- .LP -->
+The base font name list is owned by Xlib and should not be modified or
+freed by the client.
+It will be freed by a call to
+<function>XFreeFontSet</function>
+with the associated
+<type>XFontSet</type>.
+Until freed, its contents will not be modified by Xlib.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the locale name given an
+<type>XFontSet</type>,
+use
+<function>XLocaleOfFontSet</function>.
+<indexterm significance="preferred"><primary>XLocaleOfFontSet</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xlocaleoffontset'>
+<funcprototype>
+ <funcdef>char *<function>XLocaleOfFontSet</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XLocaleOfFontSet</function>
+function
+returns the name of the locale bound to the specified
+<type>XFontSet</type>,
+as a null-terminated string.
+</para>
+<para>
+<!-- .LP -->
+The returned locale name string is owned by Xlib
+and should not be modified or freed by the client.
+It may be freed by a call to
+<function>XFreeFontSet</function>
+with the associated
+<type>XFontSet</type>.
+Until freed, it will not be modified by Xlib.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+The
+<function>XFreeFontSet</function>
+function is a convenience function for freeing an output context.
+<function>XFreeFontSet</function>
+also frees its associated
+<type>XOM</type>
+if the output context was created by
+<function>XCreateFontSet</function>.
+<indexterm significance="preferred"><primary>XFreeFontSet</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfreefontset'>
+<funcprototype>
+ <funcdef>void <function>XFreeFontSet</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreeFontSet</function>
+function frees the specified font set.
+The associated base font name list, font name list,
+<structname>XFontStruct</structname>
+list, and
+<structname>XFontSetExtents</structname>,
+if any, are freed.
+</para>
+</sect2>
+<sect2 id="Obtaining_Font_Set_Metrics">
+<title>Obtaining Font Set Metrics</title>
+<!-- .XS -->
+<!-- (SN Obtaining Font Set Metrics -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Metrics for the internationalized text drawing functions
+are defined in terms of a primary draw direction,
+which is the default direction in which the character origin advances
+for each succeeding character in the string.
+The Xlib interface is currently defined to support only a left-to-right
+primary draw direction.
+The drawing origin is the position passed to the drawing function
+when the text is drawn.
+The baseline is a line drawn through the drawing origin parallel
+to the primary draw direction.
+Character ink is the pixels painted in the foreground color
+and does not include interline or intercharacter spacing
+or image text background pixels.
+</para>
+<para>
+<!-- .LP -->
+The drawing functions are allowed to implement implicit text
+directionality control, reversing the order in which characters are
+rendered along the primary draw direction in response to locale-specific
+lexical analysis of the string.
+</para>
+<para>
+<!-- .LP -->
+Regardless of the character rendering order,
+the origins of all characters are on the primary draw direction side
+of the drawing origin.
+The screen location of a particular character image may be determined with
+<function>XmbTextPerCharExtents</function>
+or
+<function>XwcTextPerCharExtents</function>.
+</para>
+<para>
+<!-- .LP -->
+The drawing functions are allowed to implement context-dependent
+rendering, where the glyphs drawn for a string are not simply a
+concatenation of the glyphs that represent each individual character.
+A string of two characters drawn with
+<function>XmbDrawString</function>
+may render differently than if the two characters
+were drawn with separate calls to
+<function>XmbDrawString</function>.
+If the client appends or inserts a character
+in a previously drawn string,
+the client may need to redraw some adjacent characters
+to obtain proper rendering.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To find out about direction-dependent rendering, use
+<function>XDirectionalDependentDrawing</function>.
+<indexterm significance="preferred"><primary>XDirectionalDependentDrawing</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdirectionaldependentdrawing'>
+<funcprototype>
+ <funcdef>Bool <function>XDirectionalDependentDrawing</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDirectionalDependentDrawing</function>
+function returns
+<symbol>True</symbol>
+if the drawing functions implement implicit text directionality;
+otherwise, it returns
+<symbol>False</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To find out about context-dependent rendering, use
+<function>XContextualDrawing</function>.
+<indexterm significance="preferred"><primary>XContextualDrawing</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcontextualdrawing'>
+<funcprototype>
+ <funcdef>Bool <function>XContextualDrawing</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XContextualDrawing</function>
+function returns
+<symbol>True</symbol>
+if text drawn with the font set might include context-dependent drawing;
+otherwise, it returns
+<symbol>False</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To find out about context-dependent or direction-dependent rendering, use
+<function>XContextDependentDrawing</function>.
+<indexterm significance="preferred"><primary>XContextDependentDrawing</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcontextdependentdrawing'>
+<funcprototype>
+ <funcdef>Bool <function>XContextDependentDrawing</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XContextDependentDrawing</function>
+function returns
+<symbol>True</symbol>
+if the drawing functions implement implicit text directionality or
+if text drawn with the font_set might include context-dependent drawing;
+otherwise, it returns
+<symbol>False</symbol>.
+</para>
+<para>
+<!-- .LP -->
+The drawing functions do not interpret newline, tab, or other control
+characters.
+The behavior when nonprinting characters other than space are drawn
+is implementation-dependent.
+It is the client's responsibility to interpret control characters
+in a text stream.
+</para>
+<para>
+<!-- .LP -->
+The maximum character extents for the fonts that are used by the text
+drawing layers can be accessed by the
+<structname>XFontSetExtents</structname>
+structure:
+<indexterm significance="preferred"><primary>XFontSetExtents</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+typedef struct {
+ XRectangle max_ink_extent; /* over all drawable characters */
+ XRectangle max_logical_extent; /* over all drawable characters */
+} XFontSetExtents;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XRectangle</structname>
+structures used to return font set metrics are the usual Xlib screen-oriented
+rectangles
+with x, y giving the upper left corner, and width and height always positive.
+</para>
+<para>
+<!-- .LP -->
+The max_ink_extent member gives the maximum extent, over all drawable characters, of
+the rectangles that bound the character glyph image drawn in the
+foreground color, relative to a constant origin.
+See
+<function>XmbTextExtents</function>
+and
+<function>XwcTextExtents</function>
+for detailed semantics.
+</para>
+<para>
+<!-- .LP -->
+The max_logical_extent member gives the maximum extent,
+over all drawable characters, of the rectangles
+that specify minimum spacing to other graphical features,
+relative to a constant origin.
+Other graphical features drawn by the client, for example,
+a border surrounding the text, should not intersect this rectangle.
+The max_logical_extent member should be used to compute minimum
+interline spacing and the minimum area that must be allowed
+in a text field to draw a given number of arbitrary characters.
+</para>
+<para>
+<!-- .LP -->
+Due to context-dependent rendering,
+appending a given character to a string may change
+the string's extent by an amount other than that character's
+individual extent.
+</para>
+<para>
+<!-- .LP -->
+The rectangles for a given character in a string can be obtained from
+<function>XmbTextPerCharExtents</function>
+or
+<function>XwcTextPerCharExtents</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the maximum extents structure given an
+<type>XFontSet</type>,
+use
+<function>XExtentsOfFontSet</function>.
+<indexterm significance="preferred"><primary>XExtentsOfFontSet</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xextentsoffontset'>
+<funcprototype>
+ <funcdef>XFontSetExtents *<function>XExtentsOfFontSet</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XExtentsOfFontSet</function>
+function returns an
+<structname>XFontSetExtents</structname>
+structure for the fonts used by the Xmb and Xwc layers
+for the given font set.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XFontSetExtents</structname>
+structure is owned by Xlib and should not be modified
+or freed by the client.
+It will be freed by a call to
+<function>XFreeFontSet</function>
+with the associated
+<type>XFontSet</type>.
+Until freed, its contents will not be modified by Xlib.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the escapement in pixels of the specified text as a value,
+use
+<function>XmbTextEscapement</function>
+or
+<function>XwcTextEscapement</function>.
+<indexterm significance="preferred"><primary>XmbTextEscapement</primary></indexterm>
+<indexterm significance="preferred"><primary>XwcTextEscapement</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmbtextescapement'>
+<funcprototype>
+ <funcdef>int <function>XmbTextEscapement</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> num_bytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<funcsynopsis id='xwctextescapement'>
+<funcprototype>
+ <funcdef>int <function>XwcTextEscapement</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+ <paramdef>wchar_t<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> num_wchars</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_bytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_wchars</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XmbTextEscapement</function>
+and
+<function>XwcTextEscapement</function>
+functions return the escapement in pixels of the specified string as a value,
+using the fonts loaded for the specified font set.
+The escapement is the distance in pixels in the primary draw
+direction from the drawing origin to the origin of the next character to
+be drawn, assuming that the rendering of the next character is not
+dependent on the supplied string.
+</para>
+<para>
+<!-- .LP -->
+Regardless of the character rendering order,
+the escapement is always positive.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the overall_ink_return and overall_logical_return arguments,
+the overall bounding box of the string's image, and a logical bounding box,
+use
+<function>XmbTextExtents</function>
+ or
+<function>XwcTextExtents</function>.
+<indexterm significance="preferred"><primary>XmbTextExtents</primary></indexterm>
+<indexterm significance="preferred"><primary>XwcTextExtents</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmbtextextents'>
+<funcprototype>
+ <funcdef>int <function>XmbTextExtents</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> num_bytes</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *overall_ink_return</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *overall_logical_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<funcsynopsis>
+<funcprototype id='xwctextextents'>
+ <funcdef>int <function>XwcTextExtents</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+ <paramdef>wchar_t<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> num_wchars</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *overall_ink_return</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *overall_logical_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_bytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_wchars</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the string argument.
+<!-- .ds Ov dimensions -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>overall_ink_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the overall ink dimensions.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>overall_logical_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the overall logical dimensions.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XmbTextExtents</function>
+and
+<function>XwcTextExtents</function>
+functions set the components of the specified overall_ink_return and
+overall_logical_return
+arguments to the overall bounding box of the string's image
+and a logical bounding box for spacing purposes, respectively.
+They return the value returned by
+<function>XmbTextEscapement</function>
+or
+<function>XwcTextEscapement</function>.
+These metrics are relative to the drawing origin of the string,
+using the fonts loaded for the specified font set.
+</para>
+<para>
+<!-- .LP -->
+If the overall_ink_return argument is non-NULL,
+it is set to the bounding box of the string's character ink.
+The overall_ink_return for a nondescending, horizontally drawn
+Latin character is conventionally entirely above the baseline;
+that is, overall_ink_return.height &lt;= -overall_ink_return.y.
+The overall_ink_return for a nonkerned character
+is entirely at, and to the right of, the origin;
+that is, overall_ink_return.x &gt;= 0.
+A character consisting of a single pixel at the origin would set
+overall_ink_return fields y = 0, x = 0, width = 1, and height = 1.
+</para>
+<para>
+<!-- .LP -->
+If the overall_logical_return argument is non-NULL,
+it is set to the bounding box that provides minimum spacing
+to other graphical features for the string.
+Other graphical features, for example, a border surrounding the text,
+should not intersect this rectangle.
+</para>
+<para>
+<!-- .LP -->
+When the
+<type>XFontSet</type>
+has missing charsets,
+metrics for each unavailable character are taken
+from the default string returned by
+<function>XCreateFontSet</function>
+so that the metrics represent the text as it will actually be drawn.
+The behavior for an invalid codepoint is undefined.
+</para>
+<para>
+<!-- .LP -->
+To determine the effective drawing origin for a character in a drawn string,
+the client should call
+<function>XmbTextPerCharExtents</function>
+on the entire string, then on the character,
+and subtract the x values of the returned
+rectangles for the character.
+This is useful to redraw portions of a line of text
+or to justify words, but for context-dependent rendering,
+the client should not assume that it can redraw the character by itself
+and get the same rendering.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain per-character information for a text string,
+use
+<function>XmbTextPerCharExtents</function>
+or
+<function>XwcTextPerCharExtents</function>.
+<indexterm significance="preferred"><primary>XmbTextPerCharExtents</primary></indexterm>
+<indexterm significance="preferred"><primary>XwcTextPerCharExtents</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmbtextpercharextents'>
+<funcprototype>
+ <funcdef>Status <function>XmbTextPerCharExtents</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> num_bytes</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *ink_array_return</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *logical_array_return</parameter></paramdef>
+ <paramdef>int<parameter> array_size</parameter></paramdef>
+ <paramdef>int<parameter> *num_chars_return</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *overall_ink_return</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *overall_logical_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<funcsynopsis id='xwctextpercharextents'>
+<funcprototype>
+ <funcdef>Status <function>XwcTextPerCharExtents</function></funcdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+ <paramdef>wchar_t<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> num_wchars</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *ink_array_return</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *logical_array_return</parameter></paramdef>
+ <paramdef>int<parameter> array_size</parameter></paramdef>
+ <paramdef>int<parameter> *num_chars_return</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *overall_ink_return</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *overall_logical_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_bytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_wchars</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ink_array_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the ink dimensions for each character.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>logical_array_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the logical dimensions for each character.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>array_size</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the size of ink_array_return and logical_array_return.
+The caller must pass in arrays of this size.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_chars_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of characters in the string argument.
+<!-- .ds Ov extents of the entire string -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>overall_ink_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the overall ink dimensions.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>overall_logical_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the overall logical dimensions.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XmbTextPerCharExtents</function>
+and
+<function>XwcTextPerCharExtents</function>
+functions return the text dimensions of each character of the specified text,
+using the fonts loaded for the specified font set.
+Each successive element of ink_array_return and logical_array_return
+is set to the successive character's drawn metrics,
+relative to the drawing origin of the string and one
+rectangle
+for each character in the supplied text string.
+The number of elements of ink_array_return and logical_array_return
+that have been set is returned to num_chars_return.
+</para>
+<para>
+<!-- .LP -->
+Each element of ink_array_return is set to the bounding box
+of the corresponding character's drawn foreground color.
+Each element of logical_array_return is set to the bounding box
+that provides minimum spacing to other graphical features
+for the corresponding character.
+Other graphical features should not intersect any of the
+logical_array_return rectangles.
+</para>
+<para>
+<!-- .LP -->
+Note that an
+<structname>XRectangle</structname>
+represents the effective drawing dimensions of the character,
+regardless of the number of font glyphs that are used to draw
+the character or the direction in which the character is drawn.
+If multiple characters map to a single character glyph,
+the dimensions of all the
+<structname>XRectangle</structname>s
+of those characters are the same.
+</para>
+<para>
+<!-- .LP -->
+When the
+<type>XFontSet</type>
+has missing charsets, metrics for each unavailable
+character are taken from the default string returned by
+<function>XCreateFontSet</function>
+so that the metrics represent the text as it will actually be drawn.
+The behavior for an invalid codepoint is undefined.
+</para>
+<para>
+<!-- .LP -->
+If the array_size is too small for the number of characters in the
+supplied text, the functions return zero
+and num_chars_return is set to the number of rectangles required.
+Otherwise, the functions return a nonzero value.
+</para>
+<para>
+<!-- .LP -->
+If the overall_ink_return or overall_logical_return argument is non-NULL,
+<function>XmbTextPerCharExtents</function>
+and
+<function>XwcTextPerCharExtents</function>
+return the maximum extent of the string's metrics to overall_ink_return
+or overall_logical_return, as returned by
+<function>XmbTextExtents</function>
+or
+<function>XwcTextExtents</function>.
+</para>
+</sect2>
+<sect2 id="Drawing_Text_Using_Font_Sets">
+<title>Drawing Text Using Font Sets</title>
+<!-- .XS -->
+<!-- (SN Drawing Text Using Font Sets -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The functions defined in this section
+draw text at a specified location in a drawable.
+They are similar to the functions
+<function>XDrawText</function>,
+<function>XDrawString</function>,
+and
+<function>XDrawImageString</function>
+except that they work with font sets instead of single fonts
+and interpret the text based on the locale of the font set
+instead of treating the bytes of the string as direct font indexes.
+See section 8.6 for details of the use of Graphics Contexts (GCs)
+and possible protocol errors.
+If a
+<errorname>BadFont</errorname>
+error is generated,
+characters prior to the offending character may have been drawn.
+</para>
+<para>
+<!-- .LP -->
+The text is drawn using the fonts loaded for the specified font set;
+the font in the GC is ignored and may be modified by the functions.
+No validation that all fonts conform to some width rule is performed.
+</para>
+<para>
+<!-- .LP -->
+The text functions
+<function>XmbDrawText</function>
+and
+<function>XwcDrawText</function>
+use the following structures:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XmbTextItem</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ char *chars; /* pointer to string */
+ int nchars; /* number of bytes */
+ int delta; /* pixel delta between strings */
+ XFontSet font_set; /* fonts, None means don't change */
+} XmbTextItem;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XwcTextItem</primary></indexterm>
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ wchar_t *chars; /* pointer to wide char string */
+ int nchars; /* number of wide characters */
+ int delta; /* pixel delta between strings */
+ XFontSet font_set; /* fonts, None means don't change */
+} XwcTextItem;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To draw text using multiple font sets in a given drawable, use
+<function>XmbDrawText</function>
+or
+<function>XwcDrawText</function>.
+<indexterm significance="preferred"><primary>XmbDrawText</primary></indexterm>
+<indexterm significance="preferred"><primary>XwcDrawText</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmbdrawtext'>
+<funcprototype>
+ <funcdef>void <function>XmbDrawText</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>XmbTextItem<parameter> *items</parameter></paramdef>
+ <paramdef>int<parameter> nitems</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<funcsynopsis id='xwcdrawtext'>
+<funcprototype>
+ <funcdef>void <function>XwcDrawText</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>XwcTextItem<parameter> *items</parameter></paramdef>
+ <paramdef>int<parameter> nitems</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>items</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of text items.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nitems</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of text items in the array.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XmbDrawText</function>
+and
+<function>XwcDrawText</function>
+functions allow complex spacing and font set shifts between text strings.
+Each text item is processed in turn, with the origin of a text
+element advanced in the primary draw direction by the escapement of the
+previous text item.
+A text item delta specifies an additional escapement of the text item
+drawing origin in the primary draw direction.
+A font_set member other than
+<symbol>None</symbol>
+in an item causes the font set to be used for this and subsequent text items
+in the text_items list.
+Leading text items with a font_set member set to
+<symbol>None</symbol>
+will not be drawn.
+</para>
+<para>
+<!-- .LP -->
+<function>XmbDrawText</function>
+and
+<function>XwcDrawText</function>
+do not perform any context-dependent rendering between text segments.
+Clients may compute the drawing metrics by passing each text segment to
+<function>XmbTextExtents</function>
+and
+<function>XwcTextExtents</function>
+or
+<function>XmbTextPerCharExtents</function>
+and
+<function>XwcTextPerCharExtents</function>.
+When the
+<type>XFontSet</type>
+has missing charsets, each unavailable character is drawn
+with the default string returned by
+<function>XCreateFontSet</function>.
+The behavior for an invalid codepoint is undefined.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To draw text using a single font set in a given drawable, use
+<function>XmbDrawString</function>
+or
+<function>XwcDrawString</function>.
+<indexterm significance="preferred"><primary>XmbDrawString</primary></indexterm>
+<indexterm significance="preferred"><primary>XwcDrawString</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmbdrawstring'>
+<funcprototype>
+ <funcdef>void <function>XmbDrawString</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> num_bytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<funcsynopsis id='xwcdrawstring'>
+<funcprototype>
+ <funcdef>void <function>XwcDrawString</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>wchar_t<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> num_wchars</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_bytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_wchars</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XmbDrawString</function>
+and
+<function>XwcDrawString</function>
+functions draw the specified text with the foreground pixel.
+When the
+<type>XFontSet</type>
+has missing charsets, each unavailable character is drawn
+with the default string returned by
+<function>XCreateFontSet</function>.
+The behavior for an invalid codepoint is undefined.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To draw image text using a single font set in a given drawable, use
+<function>XmbDrawImageString</function>
+or
+<function>XwcDrawImageString</function>.
+<indexterm significance="preferred"><primary>XmbDrawImageString</primary></indexterm>
+<indexterm significance="preferred"><primary>XwcDrawImageString</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmbdrawimagestring'>
+<funcprototype>
+ <funcdef>void <function>XmbDrawImageString</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> num_bytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<funcsynopsis id='xwcdrawimagestring'>
+<funcprototype>
+ <funcdef>void <function>XwcDrawImageString</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>XFontSet<parameter> font_set</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>wchar_t<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> num_wchars</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>font_set</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the font set.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+<!-- .ds Xy -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the character string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_bytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_wchars</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of characters in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XmbDrawImageString</function>
+and
+<function>XwcDrawImageString</function>
+functions fill a destination rectangle with the background pixel defined
+in the GC and then paint the text with the foreground pixel.
+The filled rectangle is the rectangle returned to overall_logical_return by
+<function>XmbTextExtents</function>
+or
+<function>XwcTextExtents</function>
+for the same text and
+<type>XFontSet</type>.
+</para>
+<para>
+<!-- .LP -->
+When the
+<type>XFontSet</type>
+has missing charsets, each unavailable character is drawn
+with the default string returned by
+<function>XCreateFontSet</function>.
+The behavior for an invalid codepoint is undefined.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Input_Methods">
+<title>Input Methods</title>
+<!-- .XS -->
+<!-- (SN Input Methods -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This section provides discussions of the following X Input Method
+(<acronym>XIM</acronym>) topics:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Input method overview
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Input method management
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Input method functions
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Input method values
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Input context functions
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Input context values
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Input method callback semantics
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Event filtering
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Getting keyboard input
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Input method conventions
+ </para>
+ </listitem>
+</itemizedlist>
+<sect2 id="Input_Method_Overview">
+<title>Input Method Overview</title>
+<!-- .XS -->
+<!-- (SN Input Method Overview -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This section provides definitions for terms and concepts used
+for internationalized text input and a brief overview of the
+intended use of the mechanisms provided by Xlib.
+</para>
+<para>
+<!-- .LP -->
+A large number of languages in the world use alphabets
+consisting of a small set of symbols (letters) to form words.
+To enter text into a computer in an alphabetic language,
+a user usually has a keyboard on which there exist key symbols corresponding
+to the alphabet.
+Sometimes, a few characters of an alphabetic language are missing
+on the keyboard.
+Many computer users who speak a Latin-alphabet-based language
+only have an English-based keyboard.
+They need to hit a combination of keystrokes
+to enter a character that does not exist directly on the keyboard.
+A number of algorithms have been developed for entering such characters.
+These are known as European input methods, compose input methods,
+or dead-key input methods.
+</para>
+<para>
+<!-- .LP -->
+Japanese is an example of a language with a phonetic symbol set,
+where each symbol represents a specific sound.
+There are two phonetic symbol sets in Japanese: Katakana and Hiragana.
+In general,
+Katakana is used for words that are of foreign origin,
+and Hiragana is used for writing native Japanese words.
+Collectively, the two systems are called Kana.
+Each set consists of 48 characters.
+</para>
+<para>
+<!-- .LP -->
+Korean also has a phonetic symbol set, called Hangul.
+Each of the 24 basic phonetic symbols (14 consonants and 10 vowels)
+represents a specific sound.
+A syllable is composed of two or three parts:
+the initial consonants, the vowels, and the optional last consonants.
+With Hangul,
+syllables can be treated as the basic units on which text processing is done.
+For example,
+a delete operation may work on a phonetic symbol or a syllable.
+Korean code sets include several thousands of these syllables.
+A user types the phonetic symbols that make up the syllables of the words
+to be entered.
+The display may change as each phonetic symbol is entered.
+For example,
+when the second phonetic symbol of a syllable is entered,
+the first phonetic symbol may change its shape and size.
+Likewise, when the third phonetic symbol is entered,
+the first two phonetic symbols may change their shape and size.
+</para>
+<para>
+<!-- .LP -->
+Not all languages rely solely on alphabetic or phonetic systems.
+Some languages, including Japanese and Korean, employ an
+ideographic writing system.
+In an ideographic system, rather than taking a small set of
+symbols and combining them in different ways to create words,
+each word consists of one unique symbol (or, occasionally, several symbols).
+The number of symbols can be very large:
+approximately 50,000 have been identified in Hanzi,
+the Chinese ideographic system.
+</para>
+<para>
+<!-- .LP -->
+Two major aspects of ideographic systems impact their use with computers.
+First, the standard computer character sets in Japan, China, and Korea
+include roughly 8,000 characters,
+while sets in Taiwan have between 15,000 and 30,000 characters.
+This makes it necessary to use more than one byte to represent a character.
+Second, it obviously is impractical to have a keyboard that includes
+all of a given language's ideographic symbols.
+Therefore, a mechanism is required for entering characters
+so that a keyboard with a reasonable number of keys can be used.
+Those input methods are usually based on phonetics,
+but there also exist methods based on the graphical properties of
+characters.
+</para>
+<para>
+<!-- .LP -->
+In Japan, both Kana and the ideographic system Kanji are used.
+In Korea, Hangul and sometimes the ideographic system Hanja are used.
+Now consider entering ideographs in Japan, Korea, China, and Taiwan.
+</para>
+<para>
+<!-- .LP -->
+In Japan, either Kana or English characters are typed and then a region
+is selected (sometimes automatically) for conversion to Kanji.
+Several Kanji characters may have the same phonetic representation.
+If that is the case with the string entered,
+a menu of characters is presented and
+the user must choose the appropriate one.
+If no choice is necessary or a preference has been established,
+the input method does the substitution directly.
+When Latin characters are converted to Kana or Kanji,
+it is called a romaji conversion.
+</para>
+<para>
+<!-- .LP -->
+In Korea, it is usually acceptable to keep Korean text in Hangul form,
+but some people may choose to write Hanja-originated words in Hanja
+rather than in Hangul.
+To change Hangul to Hanja,
+the user selects a region for conversion
+and then follows the same basic method as that described for Japanese.
+</para>
+<para>
+<!-- .LP -->
+Probably because there are well-accepted phonetic writing systems
+for Japanese and Korean,
+computer input methods in these countries for entering ideographs
+are fairly standard.
+Keyboard keys have both English characters and phonetic symbols
+engraved on them, and the user can switch between the two sets.
+</para>
+<para>
+<!-- .LP -->
+The situation is different for Chinese.
+While there is a phonetic system called Pinyin promoted by authorities,
+there is no consensus for entering Chinese text.
+Some vendors use a phonetic decomposition (Pinyin or another),
+others use ideographic decomposition of Chinese words,
+with various implementations and keyboard layouts.
+There are about 16 known methods, none of which is a clear standard.
+</para>
+<para>
+<!-- .LP -->
+Also, there are actually two ideographic sets used:
+Traditional Chinese (the original written Chinese)
+and Simplified Chinese.
+Several years ago,
+the People's Republic of China launched a campaign to simplify
+some ideographic characters and eliminate redundancies altogether.
+Under the plan,
+characters would be streamlined every five years.
+Characters have been revised several times now,
+resulting in the smaller, simpler set that makes up Simplified Chinese.
+</para>
+<sect3 id="Input_Method_Architecture">
+<title>Input Method Architecture</title>
+<!-- .XS -->
+<!-- (SN Input Method Architecture -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+As shown in the previous section,
+there are many different input methods in use today,
+each varying with language, culture, and history.
+A common feature of many input methods is that the user may type
+multiple keystrokes to compose a single character (or set
+of characters).
+The process of composing characters from keystrokes is called
+<emphasis remap='I'>preediting</emphasis>.
+It may require complex algorithms and large dictionaries
+involving substantial computer resources.
+</para>
+<para>
+<!-- .LP -->
+Input methods may require one or more areas in which to show the
+feedback of the actual keystrokes, to propose disambiguation to the
+user, to list dictionaries, and so on.
+The input method areas of concern are as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The <emphasis remap='I'>status</emphasis> area is a logical extension of the
+LEDs that exist on the physical keyboard.
+It is a window that is intended to present the internal state
+of the input method that is critical to the user.
+The status area may consist of text data and bitmaps or some combination.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The <emphasis remap='I'>preedit</emphasis> area displays the
+intermediate text for those languages that are composing prior to
+the client handling the data.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The <emphasis remap='I'>auxiliary</emphasis> area is used for pop-up menus and customizing
+dialogs that may be required for an input method.
+There may be multiple auxiliary areas for an input method.
+Auxiliary areas are managed by the input method independent of the client.
+Auxiliary areas are assumed to be separate dialogs,
+which are maintained by the input method.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+There are various user interaction styles used for preediting.
+The ones supported by Xlib are as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+For <emphasis remap='I'>on-the-spot</emphasis> input methods,
+preediting data will be displayed directly in the application window.
+Application data is moved to allow preedit data to appear
+at the point of insertion.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<emphasis remap='I'>Over-the-spot</emphasis> preediting means that the data is displayed in
+a preedit window that is placed over the point of insertion.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<emphasis remap='I'>Off-the-spot</emphasis> preediting means that the preedit window is
+inside the application window but not at the point of insertion.
+Often, this type of window is placed at the bottom of the application window.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<emphasis remap='I'>Root-window</emphasis> preediting refers to input methods that use a preedit
+window that is the child of
+<function>RootWindow</function>.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+It would require a lot of computing resources if portable applications
+had to include input methods for all the languages in the world.
+To avoid this,
+a goal of the Xlib design is to allow an application
+to communicate with an input method placed in a separate process.
+Such a process is called an <emphasis remap='I'>input server</emphasis>.
+The server to which the application should connect is dependent on
+the environment when the application is started up,
+that is, the user language and the actual encoding to be used for it.
+The input method connection is said to be <emphasis remap='I'>locale-dependent</emphasis>.
+It is also user-dependent.
+For a given language, the user can choose, to some extent,
+the user interface style of input method (if choice is possible among
+several).
+</para>
+<para>
+<!-- .LP -->
+Using an input server implies communication overhead,
+but applications can be migrated without relinking.
+Input methods can be implemented either as a
+stub communicating to an input server or as a local library.
+</para>
+<para>
+<!-- .LP -->
+An input method may be based on a <emphasis remap='I'>front-end</emphasis> or a <emphasis remap='I'>back-end</emphasis>
+architecture.
+In a front-end architecture,
+there are two separate connections to the X server:
+keystrokes go directly from the X server to the input method on
+one connection and other events to the regular client connection.
+The input method is then acting as a filter and sends composed strings
+to the client.
+A front-end architecture requires synchronization between the
+two connections to avoid lost key events or locking issues.
+</para>
+<para>
+<!-- .LP -->
+In a back-end architecture,
+a single X server connection is used.
+A dispatching mechanism must decide on this channel to delegate appropriate
+keystrokes to the input method.
+For instance,
+it may retain a Help keystroke for its own purpose.
+In the case where the input method is a separate process (that is, a server),
+there must be a special communication protocol between the back-end client
+and the input server.
+</para>
+<para>
+<!-- .LP -->
+A front-end architecture introduces synchronization issues
+and a filtering mechanism for noncharacter keystrokes
+(Function keys, Help, and so on).
+A back-end architecture sometimes implies more communication overhead
+and more process switching.
+If all three processes (X server, input server, client)
+are running on a single workstation,
+there are two process switches for each keystroke in a back-end
+architecture,
+but there is only one in a front-end architecture.
+</para>
+<para>
+<!-- .LP -->
+The abstraction used by a client to communicate with an input method
+is an opaque data structure represented by the
+<type>XIM</type>
+data type.
+This data structure is returned by the
+<function>XOpenIM</function>
+function, which opens an input method on a given display.
+Subsequent operations on this data structure encapsulate all communication
+between client and input method.
+There is no need for an X client to use any networking library
+or natural language package to use an input method.
+</para>
+<para>
+<!-- .LP -->
+A single input server may be used for one or more languages,
+supporting one or more encoding schemes.
+But the strings returned from an input method will always be encoded
+in the (single) locale associated with the
+<type>XIM</type>
+object.
+</para>
+</sect3>
+<sect3 id="Input_Contexts">
+<title>Input Contexts</title>
+<!-- .XS -->
+<!-- (SN Input Contexts -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides the ability to manage a multi-threaded state for text input.
+A client may be using multiple windows,
+each window with multiple text entry areas,
+and the user possibly switching among them at any time.
+The abstraction for representing the state of a particular input thread
+is called an <emphasis remap='I'>input context</emphasis>.
+The Xlib representation of an input context is an
+<type>XIC</type>.
+</para>
+<para>
+<!-- .LP -->
+An input context is the abstraction retaining the state, properties,
+and semantics of communication between a client and an input method.
+An input context is a combination of an input method, a locale
+specifying the encoding of the character strings to be returned,
+a client window, internal state information,
+and various layout or appearance characteristics.
+The input context concept somewhat matches for input the graphics context
+abstraction defined for graphics output.
+</para>
+<para>
+<!-- .LP -->
+One input context belongs to exactly one input method.
+Different input contexts may be associated with the same input method,
+possibly with the same client window.
+An
+<type>XIC</type>
+is created with the
+<function>XCreateIC</function>
+function, providing an
+<type>XIM</type>
+argument and affiliating the input context to the input method
+for its lifetime.
+When an input method is closed with
+<function>XCloseIM</function>,
+all of its affiliated input contexts should not be used any more
+(and should preferably be destroyed before closing the input method).
+</para>
+<para>
+<!-- .LP -->
+Considering the example of a client window with multiple text entry areas,
+the application programmer could, for example, choose to implement as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+As many input contexts are created as text entry areas, and the client
+will get the input accumulated on each context each time it looks up
+in that context.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A single context is created for a top-level window in the application.
+If such a window contains several text entry areas,
+each time the user moves to another text entry area,
+the client has to indicate changes in the context.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+A range of choices can be made by application designers to use
+either a single or multiple input contexts,
+according to the needs of their application.
+</para>
+</sect3>
+<sect3 id="Getting_Keyboard_Input">
+<title>Getting Keyboard Input</title>
+<!-- .XS -->
+<!-- (SN Getting Keyboard Input -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To obtain characters from an input method,
+a client must call the function
+<function>XmbLookupString</function>
+or
+<function>XwcLookupString</function>
+with an input context created from that input method.
+Both a locale and display are bound to an input method when it is opened,
+and an input context inherits this locale and display.
+Any strings returned by
+<function>XmbLookupString</function>
+or
+<function>XwcLookupString</function>
+will be encoded in that locale.
+</para>
+</sect3>
+<sect3 id="Focus_Management">
+<title>Focus Management</title>
+<!-- .XS -->
+<!-- (SN Focus Management -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+For each text entry area in which the
+<function>XmbLookupString</function>
+or
+<function>XwcLookupString</function>
+functions are used,
+there will be an associated input context.
+</para>
+<para>
+<!-- .LP -->
+When the application focus moves to a text entry area,
+the application must set the input context focus to the
+input context associated with that area.
+The input context focus is set by calling
+<function>XSetICFocus</function>
+with the appropriate input context.
+</para>
+<para>
+<!-- .LP -->
+Also, when the application focus moves out of a text entry area, the
+application should unset the focus for the associated input context
+by calling
+<function>XUnsetICFocus</function>.
+As an optimization, if
+<function>XSetICFocus</function>
+is called successively on two different input contexts,
+setting the focus on the second
+will automatically unset the focus on the first.
+</para>
+<para>
+<!-- .LP -->
+To set and unset the input context focus correctly,
+it is necessary to track application-level focus changes.
+Such focus changes do not necessarily correspond to X server focus changes.
+</para>
+<para>
+<!-- .LP -->
+If a single input context
+is being used to do input for
+multiple text entry areas, it will also be necessary
+to set the focus window of the
+input context whenever the focus window changes
+(see section 13.5.6.3).
+</para>
+</sect3>
+<sect3 id="Geometry_Management">
+<title>Geometry Management</title>
+<!-- .XS -->
+<!-- (SN Geometry Management -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+In most input method architectures
+(on-the-spot being the notable exception),
+the input method will perform the display of its own data.
+To provide better visual locality,
+it is often desirable to have the input method areas embedded within a client.
+To do this,
+the client may need to allocate space for an input method.
+Xlib provides support that allows the size and position of input method
+areas to be provided by a client.
+The input method areas that are supported for geometry management
+are the status area and the preedit area.
+</para>
+<para>
+<!-- .LP -->
+The fundamental concept on which geometry management for input method windows
+is based is the proper division of responsibilities between the
+client (or toolkit) and the input method.
+The division of responsibilities is as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The client is responsible for the geometry of the input method window.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The input method is responsible for the contents of the input method window.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+An input method is able to suggest a size to the client,
+but it cannot suggest a placement.
+Also the input method can only suggest a size.
+It does not determine the size,
+and it must accept the size it is given.
+</para>
+<para>
+<!-- .LP -->
+Before a client provides geometry management for an input method,
+it must determine if geometry management is needed.
+The input method indicates the need for geometry management
+by setting
+<symbol>XIMPreeditArea</symbol>
+or
+<symbol>XIMStatusArea</symbol>
+in its
+<structname>XIMStyles</structname>
+value returned by
+<function>XGetIMValues</function>.
+When a client has decided that it will provide geometry management
+for an input method,
+it indicates that decision by setting the
+<symbol>XNInputStyle</symbol>
+value in the
+<type>XIC</type>.
+</para>
+<para>
+<!-- .LP -->
+After a client has established with the input method
+that it will do geometry management,
+the client must negotiate the geometry with the input method.
+The geometry is negotiated by the following steps:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The client suggests an area to the input method by setting the
+<symbol>XNAreaNeeded</symbol>
+value for that area.
+If the client has no constraints for the input method,
+it either will not suggest an area or will set the width and height to zero.
+Otherwise, it will set one of the values.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The client will get the <acronym>XIC</acronym> value
+<symbol>XNAreaNeeded</symbol>.
+The input method will return its suggested size in this value.
+The input method should pay attention to any constraints suggested
+by the client.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The client sets the <acronym>XIC</acronym> value
+<symbol>XNArea</symbol>
+to inform the input method of the geometry of its window.
+The client should try to honor the geometry requested by the input method.
+The input method must accept this geometry.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Clients doing geometry management must be aware that setting other
+<acronym>XIC</acronym> values may affect the geometry desired by an input method.
+For example,
+<symbol>XNFontSet</symbol>
+and
+<symbol>XNLineSpace</symbol>
+may change the geometry desired by the input method.
+</para>
+<para>
+<!-- .LP -->
+The table of <acronym>XIC</acronym> values (see section 13.5.6)
+indicates the values that can cause the desired geometry to change
+when they are set.
+It is the responsibility of the client to renegotiate the geometry
+of the input method window when it is needed.
+</para>
+<para>
+<!-- .LP -->
+In addition,
+a geometry management callback is provided
+by which an input method can initiate a geometry change.
+</para>
+</sect3>
+<sect3 id="Event_Filtering">
+<title>Event Filtering</title>
+<!-- .XS -->
+<!-- (SN Event Filtering -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+A filtering mechanism is provided to allow input methods
+to capture X events transparently to clients.
+It is expected that toolkits (or clients) using
+<function>XmbLookupString</function>
+or
+<function>XwcLookupString</function>
+will call this filter at some point in the event processing mechanism
+to make sure that events needed by an input method can be filtered
+by that input method.
+</para>
+<para>
+<!-- .LP -->
+If there were no filter,
+a client could receive and discard events that are necessary
+for the proper functioning of an input method.
+The following provides a few examples of such events:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Expose events on preedit window in local mode.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Events may be used by an input method to communicate with an input server.
+Such input server protocol-related events have to be intercepted
+if one does not want to disturb client code.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Key events can be sent to a filter before they are bound
+to translations such as those the X Toolkit Intrinsics library provides.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Clients are expected to get the <acronym>XIC</acronym> value
+<symbol>XNFilterEvents</symbol>
+and augment the event mask for the client window with that event mask.
+This mask may be zero.
+</para>
+</sect3>
+<sect3 id="Callbacks">
+<title>Callbacks</title>
+<!-- .XS -->
+<!-- (SN Callbacks -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+When an on-the-spot input method is implemented,
+only the client can insert or delete preedit data in place
+and possibly scroll existing text.
+This means that the echo of the keystrokes has to be achieved
+by the client itself, tightly coupled with the input method logic.
+</para>
+<para>
+<!-- .LP -->
+When the user enters a keystroke,
+the client calls
+<function>XmbLookupString</function>
+or
+<function>XwcLookupString</function>.
+At this point, in the on-the-spot case,
+the echo of the keystroke in the preedit has not yet been done.
+Before returning to the client logic that handles the input characters,
+the look-up function
+must call the echoing logic to insert the new keystroke.
+If the keystrokes entered so far make up a character,
+the keystrokes entered need to be deleted,
+and the composed character will be returned.
+Hence, what happens is that, while being called by client code,
+the input method logic has to call back to the client before it returns.
+The client code, that is, a callback procedure,
+is called from the input method logic.
+</para>
+<para>
+<!-- .LP -->
+There are a number of cases where the input method logic has to
+call back the client.
+Each of those cases is associated with a well-defined callback action.
+It is possible for the client to specify, for each input context,
+what callback is to be called for each action.
+</para>
+<para>
+<!-- .LP -->
+There are also callbacks provided for feedback of status information
+and a callback to initiate a geometry request for an input method.
+</para>
+</sect3>
+<sect3 id="Visible_Position_Feedback_Masks">
+<title>Visible Position Feedback Masks</title>
+<!-- .XS -->
+<!-- (SN Visible Position Feedback Masks -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+In the on-the-spot input style, there is a problem when
+attempting to draw preedit strings that are longer than the
+available space. Once the display area is exceeded, it is not
+clear how best to display the preedit string.
+The visible position feedback masks of
+<structname>XIMText</structname>
+help resolve this problem by allowing the input method to specify hints that
+indicate the essential portions of the preedit string.
+For example, such hints can help developers implement
+scrolling of a long preedit string within a short preedit display area.
+</para>
+</sect3>
+<sect3 id="Preedit_String_Management">
+<title>Preedit String Management</title>
+<!-- .XS -->
+<!-- (SN Preedit String Management -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+As highlighted before, the input method architecture provides
+preediting, which supports a type of preprocessor input composition.
+In this case, composition consists of interpreting a sequence
+of key events and returning a committed string via
+<function>XmbLookupString</function>
+or
+<function>XwcLookupString</function>.
+This provides the basics for input methods.
+</para>
+<para>
+<!-- .LP -->
+In addition to preediting based on key events, a general framework
+is provided to give a client that desires it more advanced preediting based
+on the text within the client. This framework is called
+<emphasis remap='I'>string conversion</emphasis> and is provided using <acronym>XIC</acronym> values.
+The fundamental concept of string conversion
+is to allow the input method to manipulate the client's
+text independent of any user preediting operation.
+</para>
+<para>
+<!-- .LP -->
+The need for string conversion is based on
+language needs and input method capabilities.
+The following are some examples of string conversion:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Transliteration conversion provides language-specific conversions
+within the input method.
+In the case of Korean input, users wish to convert a Hangul string
+into a Hanja string while in preediting, after preediting,
+or in other situations (for example, on a selected string).
+The conversion is triggered when the user
+presses a Hangul-to-Hanja key sequence (which may be input method specific).
+Sometimes the user may want to invoke the conversion after finishing
+preediting or on a user-selected string.
+Thus, the string to be converted is in an application buffer, not in
+the preedit area of the input method. The string conversion services
+allow the client to request this transliteration conversion from the
+input method.
+There are many other transliteration conversions defined for
+various languages, for example, Kana-to-Kanji conversion in Japanese.
+<!-- .sp -->
+The key to remember is that transliteration conversions are triggered
+at the request of the user and returned to the client
+immediately without affecting the preedit area of the input method.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Reconversion of a previously committed string or
+a selected string is supported by many input methods as a
+convenience to the user.
+For example, a user tends to mistype the commit key while
+preediting. In that case, some input methods provide a special
+key sequence to request a ``reconvert'' operation on the
+committed string, similiar to the undo facility provided by most
+text editors.
+Another example is where the user is proofreading a document
+that has some misconversions from preediting and wants to correct
+the misconverted text. Such reconversion is again triggered
+by the user invoking some special action, but reconversions should
+not affect the state of the preedit area.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Context-sensitive conversion is required for some languages
+and input methods that need to retrieve text that surrounds the
+current spot location (cursor position) of the client's buffer.
+Such text is needed when the preediting operation depends on
+some surrounding characters (usually preceding the spot location).
+For example,
+in Thai language input, certain character sequences may be invalid and
+the input method may want to check whether characters constitute a
+valid word. Input methods that do such context-dependent
+checking need to retrieve the characters surrounding the current
+cursor position to obtain complete words.
+<!-- .sp -->
+Unlike other conversions, this conversion is not explicitly
+requested by the user.
+Input methods that provide such context-sensitive conversion
+continuously need to request context from the client, and any change
+in the context of the spot location may affect such conversions.
+The client's context would be needed if the user moves the cursor
+and starts editing again.
+<!-- .sp -->
+For this reason, an input method supporting this type of conversion
+should take notice of when the client calls
+<function>XmbResetIC</function>
+or
+<function>XwcResetIC</function>,
+which is usually an indication of a context change.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Context-sensitive conversions just need a copy of the client's text,
+while other conversions replace the client's text with new text
+to achieve the reconversion or transliteration. Yet in all
+cases the result of a conversion, either immediately or via preediting,
+is returned by the
+<function>XmbLookupString</function>
+and
+<function>XwcLookupString</function>
+functions.
+</para>
+<para>
+<!-- .LP -->
+String conversion support is dependent on the availability of the
+<symbol>XNStringConversion</symbol>
+or
+<symbol>XNStringConversionCallback</symbol>
+<acronym>XIC</acronym> values.
+Because the input method may not support string conversions,
+clients have to query the availability of string conversion
+operations by checking the supported <acronym>XIC</acronym> values list by calling
+<function>XGetIMValues</function>
+with the
+<symbol>XNQueryICValuesList</symbol>
+IM value.
+</para>
+<para>
+<!-- .LP -->
+The difference between these two values is whether the
+conversion is invoked by the client or the input method.
+The
+<symbol>XNStringConversion</symbol>
+<acronym>XIC</acronym> value is used by clients to request
+a string conversion from the input method. The client
+is responsible for determining which events are used
+to trigger the string conversion and whether the string to be
+converted should be copied or deleted. The type of conversion
+is determined by the input method; the client can only
+pass the string to be converted. The client is guaranteed that
+no
+<symbol>XNStringConversionCallback</symbol>
+will be issued when this value is set; thus, the client need
+only set one of these values.
+</para>
+<para>
+<!-- .LP -->
+The
+<symbol>XNStringConversionCallback</symbol>
+<acronym>XIC</acronym> value is used by the client to notify the input method that
+it will accept requests from the input method for string conversion.
+If this value is set,
+it is the input method's responsibility to determine which
+events are used to trigger the string conversion.
+When such events occur, the input method issues a call to the
+client-supplied procedure to retrieve the string to be converted. The client's
+callback procedure is notified whether to copy or delete the string and
+is provided with hints as to the amount of text needed.
+The
+<structname>XIMStringConversionCallbackStruct</structname>
+specifies which text should be passed back to the input method.
+</para>
+<para>
+<!-- .LP -->
+Finally, the input method may call the client's
+<symbol>XNStringConversionCallback</symbol>
+procedure multiple times if the string returned from the callback is
+not sufficient to perform a successful conversion. The arguments
+to the client's procedure allow the input method to define a
+position (in character units) relative to the client's cursor position
+and the size of the text needed. By varying the position and size of
+the desired text in subsequent callbacks, the input method can retrieve
+additional text.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+</sect2>
+<sect2 id="Input_Method_Management">
+<title>Input Method Management</title>
+<!-- .XS -->
+<!-- (SN Input Method Management -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The interface to input methods might appear to be simply creating
+an input method
+(<function>XOpenIM</function>)
+and freeing an input method
+(<function>XCloseIM</function>).
+However, input methods may
+require complex communication with input method servers (IM servers),
+for example:
+</para>
+
+<itemizedlist>
+ <listitem>
+ <para>
+If the X server, IM server, and X clients are started asynchronously,
+some clients may attempt to connect to the IM server before it is
+fully operational, and fail.
+Therefore, some mechanism is needed to allow clients to detect when an IM
+server has started.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+It is up to clients to decide what should be done when an IM server is
+not available (for example, wait, or use some other IM server).
+</para>
+<para>
+<!-- .LP -->
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Some input methods may allow the underlying IM server to be switched.
+Such customization may be desired without restarting the entire client.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+To support management of input methods in these cases, the following
+functions are provided:
+</para>
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <tbody>
+ <row>
+ <entry><function>XRegisterIMInstantiateCallback</function></entry>
+ <entry>This function allows clients to register a callback procedure
+ to be called when Xlib detects that an IM server is up and available.</entry>
+ </row>
+ <row>
+ <entry><function>XOpenIM</function></entry>
+ <entry>A client calls this function as a result of the callback procedure
+ being called.</entry>
+ </row>
+ <row>
+ <entry><function>XSetIMValues</function>, <function>XSetICValues</function></entry>
+ <entry>These functions use the <acronym>XIM</acronym> and <acronym>XIC</acronym> values,
+ <symbol>XNDestroyCallback</symbol>,
+ to allow a client
+ to register a callback procedure to be called when Xlib detects that
+ an IM server that was associated with an opened
+ input method is no longer available.
+ In addition, this function can be used to switch IM servers for those input
+ methods that support such functionality. The IM value for switching IM
+ servers is implementation-dependent; see the description below about
+ switching IM servers.</entry>
+ </row>
+ <row>
+ <entry><function>XUnregisterIMInstantiateCallback</function></entry>
+ <entry>This function removes a callback procedure registered by the client.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+Input methods that support switching of IM servers may exhibit some
+side-effects:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The input method will ensure that any new IM server supports any of the
+input styles being used by input contexts already associated with the
+input method.
+However, the list of supported input styles may be different.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Geometry management requests on previously created input contexts
+may be initiated by the new IM server.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+</para>
+<sect3 id="Hot_Keys">
+<title>Hot Keys</title>
+<!-- .XS -->
+<!-- (SN Hot Keys -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Some clients need to guarantee which keys can be used to escape from the
+input method, regardless of the input method state;
+for example, the client-specific Help key or the keys to move the
+input focus.
+The HotKey mechanism allows clients
+to specify a set of keys for this purpose. However, the input
+method might not allow clients to specify hot keys.
+Therefore, clients have to query support of hot keys by checking the
+supported <acronym>XIC</acronym> values list by calling
+<function>XGetIMValues</function>
+with the
+<symbol>XNQueryICValuesList</symbol>
+IM value.
+When the hot keys specified conflict with the key bindings of the
+input method, hot keys take precedence over the key bindings of the input
+method.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+<sect3 id="Preedit_State_Operation">
+<title>Preedit State Operation</title>
+<!-- .XS -->
+<!-- (SN Preedit State Operation -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+An input method may have several internal states, depending on its
+implementation and the locale. However, one state that is
+independent of locale and implementation is whether the input method
+is currently performing a preediting operation.
+Xlib provides the ability for an application to manage the preedit state
+programmatically. Two methods are provided for
+retrieving the preedit state of an input context.
+One method is to query the state by calling
+<function>XGetICValues</function>
+with the
+<symbol>XNPreeditState</symbol>
+<acronym>XIC</acronym> value.
+Another method is to receive notification whenever
+the preedit state is changed. To receive such notification,
+an application needs to register a callback by calling
+<function>XSetICValues</function>
+with the
+<symbol>XNPreeditStateNotifyCallback</symbol>
+<acronym>XIC</acronym> value.
+In order to change the preedit state programmatically, an application
+needs to call
+<function>XSetICValues</function>
+with
+<symbol>XNPreeditState</symbol>.
+</para>
+<para>
+<!-- .LP -->
+Availability of the preedit state is input method dependent. The input
+method may not provide the ability to set the state or to
+retrieve the state programmatically. Therefore, clients have to
+query availability of preedit state operations by checking the
+supported <acronym>XIC</acronym> values list by calling
+<function>XGetIMValues</function>
+with the
+<symbol>XNQueryICValuesList</symbol>
+IM value.
+</para>
+</sect3>
+</sect2>
+<sect2 id="Input_Method_Functions">
+<title>Input Method Functions</title>
+<!-- .XS -->
+<!-- (SN Input Method Functions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To open a connection, use
+<function>XOpenIM</function>.
+<indexterm significance="preferred"><primary>XOpenIM</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xopenim'>
+<funcprototype>
+ <funcdef>XIM <function>XOpenIM</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XrmDatabase<parameter> db</parameter></paramdef>
+ <paramdef>char<parameter> *res_name</parameter></paramdef>
+ <paramdef>char<parameter> *res_class</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>db</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a pointer to the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>res_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the full resource name of the application.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>res_class</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the full class name of the application.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XOpenIM</function>
+function opens an input method,
+matching the current locale and modifiers specification.
+Current locale and modifiers are bound to the input method at opening time.
+The locale associated with an input method cannot be changed dynamically.
+This implies that the strings returned by
+<function>XmbLookupString</function>
+or
+<function>XwcLookupString</function>,
+for any input context affiliated with a given input method,
+will be encoded in the locale current at the time the input method is opened.
+</para>
+<para>
+<!-- .LP -->
+The specific input method to which this call will be routed
+is identified on the basis of the current locale.
+<function>XOpenIM</function>
+will identify a default input method corresponding to the
+current locale.
+That default can be modified using
+<function>XSetLocaleModifiers</function>
+for the input method modifier.
+</para>
+<para>
+<!-- .LP -->
+The db argument is the resource database to be used by the input method
+for looking up resources that are private to the input method.
+It is not intended that this database be used to look
+up values that can be set as IC values in an input context.
+If db is NULL,
+no database is passed to the input method.
+</para>
+<para>
+<!-- .LP -->
+The res_name and res_class arguments specify the resource name
+and class of the application.
+They are intended to be used as prefixes by the input method
+when looking up resources that are common to all input contexts
+that may be created for this input method.
+The characters used for resource names and classes must be in the
+X Portable Character Set.
+The resources looked up are not fully specified
+if res_name or res_class is NULL.
+</para>
+<para>
+<!-- .LP -->
+The res_name and res_class arguments are not assumed to exist beyond
+the call to
+<function>XOpenIM</function>.
+The specified resource database is assumed to exist for the lifetime
+of the input method.
+</para>
+<para>
+<!-- .LP -->
+<function>XOpenIM</function>
+returns NULL if no input method could be opened.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To close a connection, use
+<function>XCloseIM</function>.
+<indexterm significance="preferred"><primary>XCloseIM</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcloseim'>
+<funcprototype>
+ <funcdef>Status <function>XCloseIM</function></funcdef>
+ <paramdef>XIM<parameter> im</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>im</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input method.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCloseIM</function>
+function closes the specified input method.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set input method attributes, use
+<function>XSetIMValues</function>.
+<indexterm significance="preferred"><primary>XSetIMValues</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetimvalues'>
+<funcprototype>
+ <funcdef>char *<function>XSetIMValues</function></funcdef>
+ <paramdef>XIM<parameter> im</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>im</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input method.
+<!-- .ds Al \ to set <acronym>XIM</acronym> values -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ ...
+ </term>
+ <listitem>
+ <para>
+Specifies the variable-length argument list(Al.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetIMValues</function>
+function presents a variable argument list programming interface
+for setting attributes of the specified input method.
+It returns NULL if it succeeds;
+otherwise,
+it returns the name of the first argument that could not be set.
+Xlib does not attempt to set arguments from the supplied list that
+follow the failed argument;
+all arguments in the list preceding the failed argument have been set
+correctly.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To query an input method, use
+<function>XGetIMValues</function>.
+<indexterm significance="preferred"><primary>XGetIMValues</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetimvalues'>
+<funcprototype>
+ <funcdef>char *<function>XGetIMValues</function></funcdef>
+ <paramdef>XIM<parameter> im</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>im</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input method.
+<!-- .ds Al \ to get XIM values -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ ...
+ </term>
+ <listitem>
+ <para>
+Specifies the variable length argument list(Al.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetIMValues</function>
+function presents a variable argument list programming interface
+for querying properties or features of the specified input method.
+This function returns NULL if it succeeds;
+otherwise,
+it returns the name of the first argument that could not be obtained.
+</para>
+<para>
+<!-- .LP -->
+Each <acronym>XIM</acronym> value argument (following a name) must point to
+a location where the <acronym>XIM</acronym> value is to be stored.
+That is, if the <acronym>XIM</acronym> value is of type T,
+the argument must be of type T*.
+If T itself is a pointer type,
+then
+<function>XGetIMValues</function>
+allocates memory to store the actual data,
+and the client is responsible for freeing this data by calling
+<function>XFree</function>
+with the returned pointer.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the display associated with an input method, use
+<function>XDisplayOfIM</function>.
+<indexterm significance="preferred"><primary>XDisplayOfIM</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdisplayofim'>
+<funcprototype>
+ <funcdef>Display *<function>XDisplayOfIM</function></funcdef>
+ <paramdef>XIM<parameter> im</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>im</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input method.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDisplayOfIM</function>
+function returns the display associated with the specified input method.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To get the locale associated with an input method, use
+<function>XLocaleOfIM</function>.
+<indexterm significance="preferred"><primary>XLocaleOfIM</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xlocaleofim'>
+<funcprototype>
+ <funcdef>char *<function>XLocaleOfIM</function></funcdef>
+ <paramdef>XIM<parameter> im</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>im</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input method.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XLocaleOfIM</function>
+function returns the locale associated with the specified input method.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To register an input method instantiate callback, use
+<function>XRegisterIMInstantiateCallback</function>.
+<indexterm significance="preferred"><primary>XRegisterIMInstantiateCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xregisteriminstantiatecallback'>
+<funcprototype>
+ <funcdef>Bool <function>XRegisterIMInstantiateCallback</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XrmDatabase<parameter> db</parameter></paramdef>
+ <paramdef>char<parameter> *res_name</parameter></paramdef>
+ <paramdef>char<parameter> *res_class</parameter></paramdef>
+ <paramdef>XIMProc<parameter> callback</parameter></paramdef>
+ <paramdef>XPointer<parameter> *client_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>db</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a pointer to the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>res_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the full resource name of the application.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>res_class</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the full class name of the application.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>callback</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a pointer to the input method instantiate callback.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XRegisterIMInstantiateCallback</function>
+function registers a callback to be invoked whenever a new input method
+becomes available for the specified display that matches the current
+locale and modifiers.
+</para>
+<para>
+<!-- .LP -->
+The function returns
+<symbol>True</symbol>
+ if it succeeds; otherwise, it returns
+<symbol>False</symbol>.
+</para>
+<para>
+<!-- .LP -->
+The generic prototype is as follows:
+<indexterm significance="preferred"><primary>IMInstantiateCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='iminstantiatecallback'>
+<funcprototype>
+ <funcdef>void <function><replaceable>IMInstantiateCallback</replaceable></function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XPointer<parameter> call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Not used for this callback and always passed as NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+To unregister an input method instantiation callback, use
+<function>XUnregisterIMInstantiateCallback</function>.
+<indexterm significance="preferred"><primary>XUnregisterIMInstantiateCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xunregisteriminstantiatecallback'>
+<funcprototype>
+ <funcdef>Bool <function>XUnregisterIMInstantiateCallback</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XrmDatabase<parameter> db</parameter></paramdef>
+ <paramdef>char<parameter> *res_name</parameter></paramdef>
+ <paramdef>char<parameter> *res_class</parameter></paramdef>
+ <paramdef>XIMProc<parameter> callback</parameter></paramdef>
+ <paramdef>XPointer<parameter> *client_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>db</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a pointer to the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>res_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the full resource name of the application.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>res_class</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the full class name of the application.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>callback</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a pointer to the input method instantiate callback.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUnregisterIMInstantiateCallback</function>
+function removes an input method instantiation callback previously
+registered.
+The function returns
+<symbol>True</symbol>
+if it succeeds; otherwise, it returns
+<symbol>False</symbol>.
+</para>
+</sect2>
+<sect2 id="Input_Method_Values">
+<title>Input Method Values</title>
+<!-- .XS -->
+<!-- (SN Input Method Values -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The following table describes how <acronym>XIM</acronym> values are interpreted
+by an input method.
+The first column lists the <acronym>XIM</acronym> values.
+The second column indicates how each of the <acronym>XIM</acronym> values
+are treated by that input style.
+</para>
+<para>
+<!-- .LP -->
+</para>
+<para>
+<!-- .LP -->
+The following keys apply to this table.
+</para>
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <thead>
+ <row>
+ <entry>Key</entry>
+ <entry>Explanation</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>D</entry>
+ <entry>This value may be set using
+ <function>XSetIMValues</function>.
+ If it is not set,
+ a default is provided.</entry>
+ </row>
+ <row>
+ <entry>S</entry>
+ <entry>This value may be set using <function>XSetIMValues</function>.</entry>
+ </row>
+ <row>
+ <entry>G</entry>
+ <entry>This value may be read using <function>XGetIMValues</function>.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<!-- .LP -->
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <thead>
+ <row>
+ <entry><acronym>XIM</acronym> Value</entry>
+ <entry>Key</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><symbol>XNQueryInputStyle</symbol></entry>
+ <entry>G</entry>
+ </row>
+ <row>
+ <entry><symbol>XNResourceName</symbol></entry>
+ <entry>D-S-G</entry>
+ </row>
+ <row>
+ <entry><symbol>XNResourceClass</symbol></entry>
+ <entry>D-S-G</entry>
+ </row>
+ <row>
+ <entry><symbol>XNDestroyCallback</symbol></entry>
+ <entry>D-S-G</entry>
+ </row>
+ <row>
+ <entry><symbol>XNQueryIMValuesList</symbol></entry>
+ <entry>G</entry>
+ </row>
+ <row>
+ <entry><symbol>XNQueryICValuesList</symbol></entry>
+ <entry>G</entry>
+ </row>
+ <row>
+ <entry><symbol>XNVisiblePosition</symbol></entry>
+ <entry>G</entry>
+ </row>
+ <row>
+ <entry><symbol>XNR6PreeditCallback</symbol></entry>
+ <entry>D-S-G</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+<symbol>XNR6PreeditCallback</symbol>
+is obsolete and its use is not recommended (see section 13.5.4.6).
+</para>
+
+<sect3 id="Query_Input_Style">
+<title>Query Input Style</title>
+<!-- .XS -->
+<!-- (SN Query Input Style -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+A client should always query the input method to determine which input
+styles are supported.
+The client should then find an input style it is capable of supporting.
+</para>
+<para>
+<!-- .LP -->
+If the client cannot find an input style that it can support,
+it should negotiate with the user the continuation of the program
+(exit, choose another input method, and so on).
+</para>
+<para>
+<!-- .LP -->
+The argument value must be a pointer to a location
+where the returned value will be stored.
+The returned value is a pointer to a structure of type
+<structname>XIMStyles</structname>.
+Clients are responsible for freeing the
+<structname>XIMStyles</structname>
+structure.
+To do so, use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XIMStyles</structname>
+structure is defined as follows:
+</para>
+
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XIMStyle</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPreeditArea</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPreeditCallbacks</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPreeditPosition</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPreeditNothing</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPreeditNone</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMStatusArea</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMStatusCallbacks</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMStatusNothing</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMStatusNone</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMStyles</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+typedef unsigned long XIMStyle;
+
+
+#define XIMPreeditArea 0x0001L
+#define XIMPreeditCallbacks 0x0002L
+#define XIMPreeditPosition 0x0004L
+#define XIMPreeditNothing 0x0008L
+#define XIMPreeditNone 0x0010L
+
+#define XIMStatusArea 0x0100L
+#define XIMStatusCallbacks 0x0200L
+#define XIMStatusNothing 0x0400L
+#define XIMStatusNone 0x0800L
+
+typedef struct {
+ unsigned short count_styles;
+ XIMStyle * supported_styles;
+} XIMStyles;
+
+</literallayout>
+
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+An
+<structname>XIMStyles</structname>
+structure contains the number of input styles supported
+in its count_styles field.
+This is also the size of the supported_styles array.
+</para>
+<para>
+<!-- .LP -->
+The supported styles is a list of bitmask combinations,
+which indicate the combination of styles for each of the areas supported.
+These areas are described later.
+Each element in the list should select one of the bitmask values for
+each area.
+The list describes the complete set of combinations supported.
+Only these combinations are supported by the input method.
+</para>
+<para>
+<!-- .LP -->
+The preedit category defines what type of support is provided
+by the input method for preedit information.
+</para>
+<indexterm significance="preferred"><primary>XIMPreeditArea</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPreeditPosition</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPreeditCallbacks</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPreeditNothing</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPreeditNone</primary></indexterm>
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <tbody>
+ <row>
+ <entry><symbol>XIMPreeditArea</symbol></entry>
+ <entry>If chosen,
+ the input method would require the client to provide some area values
+ for it to do its preediting.
+ Refer to <acronym>XIC</acronym> values
+ <symbol>XNArea</symbol>
+ and
+ <symbol>XNAreaNeeded</symbol>.</entry>
+ </row>
+ <row>
+ <entry><symbol>XIMPreeditPosition</symbol></entry>
+ <entry>If chosen,
+ the input method would require the client to provide positional values.
+ Refer to <acronym>XIC</acronym> values
+ <symbol>XNSpotLocation</symbol>
+ and
+ <symbol>XNFocusWindow</symbol>.</entry>
+ </row>
+ <row>
+ <entry><symbol>XIMPreeditCallbacks</symbol></entry>
+ <entry>If chosen,
+ the input method would require the client to define the set of preedit callbacks.
+ Refer to <acronym>XIC</acronym> values
+ <symbol>XNPreeditStartCallback</symbol>,
+ <symbol>XNPreeditDoneCallback</symbol>,
+ <symbol>XNPreeditDrawCallback</symbol>,
+ and
+ <symbol>XNPreeditCaretCallback</symbol>.</entry>
+ </row>
+ <row>
+ <entry><symbol>XIMPreeditNothing</symbol></entry>
+ <entry>If chosen, the input method can function without any preedit values.</entry>
+ </row>
+ <row>
+ <entry><symbol>XIMPreeditNone</symbol></entry>
+ <entry>The input method does not provide any preedit feedback.
+ Any preedit value is ignored.
+ This style is mutually exclusive with the other preedit styles.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+The status category defines what type of support is provided
+by the input method for status information.
+</para>
+<indexterm significance="preferred"><primary>XIMStatusArea</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMStatusCallbacks</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMStatusNothing</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMStatusNone</primary></indexterm>
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <tbody>
+ <row>
+ <entry><symbol>XIMStatusArea</symbol></entry>
+ <entry>The input method requires the client to provide
+ some area values for it to do its status feedback.
+ See
+ <symbol>XNArea</symbol>
+ and
+ <symbol>XNAreaNeeded</symbol>.</entry>
+ </row>
+ <row>
+ <entry><symbol>XIMStatusCallbacks</symbol></entry>
+ <entry>The input method requires the client to define the set of status callbacks,
+ <symbol>XNStatusStartCallback</symbol>,
+ <symbol>XNStatusDoneCallback</symbol>,
+ and
+ <symbol>XNStatusDrawCallback</symbol>.</entry>
+ </row>
+ <row>
+ <entry><symbol>XIMStatusNothing</symbol></entry>
+ <entry>The input method can function without any status values.</entry>
+ </row>
+ <row>
+ <entry><symbol>XIMStatusNone</symbol></entry>
+ <entry>The input method does not provide any status feedback.
+ If chosen, any status value is ignored.
+ This style is mutually exclusive with the other status styles.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+</sect3>
+<sect3 id="Resource_Name_and_Class_c">
+<title>Resource Name and Class</title>
+<!-- .XS -->
+<!-- (SN Resource Name and Class -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNResourceName</symbol>
+and
+<symbol>XNResourceClass</symbol>
+arguments are strings that specify the full name and class
+used by the input method.
+These values should be used as prefixes for the name and class
+when looking up resources that may vary according to the input method.
+If these values are not set,
+the resources will not be fully specified.
+</para>
+<para>
+<!-- .LP -->
+It is not intended that values that can be set as <acronym>XIM</acronym> values be
+set as resources.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+<sect3 id="Destroy_Callback">
+<title>Destroy Callback</title>
+<!-- .XS -->
+<!-- (SN Destroy Callback -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNDestroyCallback</symbol>
+argument is a pointer to a structure of type
+<structname>XIMCallback</structname>.
+<symbol>XNDestroyCallback</symbol>
+is triggered when an input method stops its service for any reason.
+After the callback is invoked, the input method is closed and the
+associated input context(s) are destroyed by Xlib.
+Therefore, the client should not call
+<function>XCloseIM</function>
+or
+<function>XDestroyIC</function>.
+</para>
+<para>
+<!-- .LP -->
+The generic prototype of this callback function is as follows:
+<indexterm significance="preferred"><primary>DestroyCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='destroycallback'>
+<funcprototype>
+ <funcdef>void <function><replaceable>DestroyCallback</replaceable></function></funcdef>
+ <paramdef>XIM<parameter> im</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XPointer<parameter> call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>im</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input method.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Not used for this callback and always passed as NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+A DestroyCallback is always called with a NULL call_data argument.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+<sect3 id="Query_IM_IC_Values_List">
+<title>Query IM/IC Values List</title>
+<!-- .XS -->
+<!-- (SN Query IM/IC Values List -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<symbol>XNQueryIMValuesList</symbol>
+and
+<symbol>XNQueryICValuesList</symbol>
+are used to query about <acronym>XIM</acronym> and <acronym>XIC</acronym> values supported by the input method.
+</para>
+<para>
+<!-- .LP -->
+The argument value must be a pointer to a location where the returned
+value will be stored. The returned value is a pointer to a structure
+of type
+<structname>XIMValuesList</structname>.
+Clients are responsible for freeing the
+<structname>XIMValuesList</structname>
+structure.
+To do so, use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XIMValuesList</structname>
+structure is defined as follows:
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ unsigned short count_values;
+ char **supported_values;
+} XIMValuesList;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+</para>
+</sect3>
+<sect3 id="Visible_Position">
+<title>Visible Position</title>
+<!-- .XS -->
+<!-- (SN Visible Position -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNVisiblePosition</symbol>
+argument indicates whether the visible position masks of
+<type>XIMFeedback</type>
+in
+<structname>XIMText</structname>
+are available.
+</para>
+<para>
+<!-- .LP -->
+The argument value must be a pointer to a location where the returned
+value will be stored. The returned value is of type
+<type>Bool</type>.
+If the returned value is
+<symbol>True</symbol>,
+the input method uses the visible position masks of
+<type>XIMFeedback</type>
+in
+<structname>XIMText</structname>;
+otherwise, the input method does not use the masks.
+</para>
+<para>
+<!-- .LP -->
+Because this <acronym>XIM</acronym> value is optional, a client should call
+<function>XGetIMValues</function>
+with argument
+<symbol>XNQueryIMValuesList</symbol>
+before using this argument.
+If the
+<symbol>XNVisiblePosition</symbol>
+does not exist in the IM values list returned from
+<symbol>XNQueryIMValuesList</symbol>,
+the visible position masks of
+<type>XIMFeedback</type>
+in
+<structname>XIMText</structname>
+are not used to indicate the visible position.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+<sect3 id="Preedit_Callback_Behavior">
+<title>Preedit Callback Behavior</title>
+<!-- .XS -->
+<!-- (SN Preedit Callback Behavior -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNR6PreeditCallback</symbol>
+argument originally included in the X11R6 specification has been
+deprecated.\(dg
+<!-- .\" If XNR6PreeditCallbackBehavior is not deprecated, then its type -->
+<!-- .\" should be changed from *Bool to Bool. -->
+<!-- .FS \(dg -->
+During formulation of the X11R6 specification, the behavior of
+the R6 PreeditDrawCallbacks was going to differ significantly from
+that of the R5 callbacks.
+Late changes to the specification converged the R5 and R6 behaviors,
+eliminating the need for
+<symbol>XNR6PreeditCallback</symbol>.
+Unfortunately, this argument was not removed from the R6 specification
+before it was published.
+<!-- .FE -->
+</para>
+<para>
+<!-- .LP -->
+The
+<symbol>XNR6PreeditCallback</symbol>
+argument indicates whether the behavior of preedit callbacks regarding
+<structname>XIMPreeditDrawCallbackStruct</structname>
+values follows Release 5 or Release 6 semantics.
+</para>
+<para>
+<!-- .LP -->
+The value is of type
+<type>Bool</type>.
+When querying for
+<symbol>XNR6PreeditCallback</symbol>,
+if the returned value is
+<symbol>True</symbol>,
+the input method uses the Release 6 behavior;
+otherwise, it uses the Release 5 behavior.
+The default value is
+<symbol>False</symbol>.
+In order to use Release 6 semantics, the value of
+<symbol>XNR6PreeditCallback</symbol>
+must be set to
+<symbol>True</symbol>.
+</para>
+<para>
+<!-- .LP -->
+Because this <acronym>XIM</acronym> value is optional, a client should call
+<function>XGetIMValues</function>
+with argument
+<symbol>XNQueryIMValuesList</symbol>
+before using this argument.
+If the
+<symbol>XNR6PreeditCallback</symbol>
+does not exist in the IM values list returned from
+<symbol>XNQueryIMValuesList</symbol>,
+the PreeditCallback behavior is Release 5 semantics.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+</sect2>
+<sect2 id="Input_Context_Functions">
+<title>Input Context Functions</title>
+<!-- .XS -->
+<!-- (SN Input Context Functions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+An input context is an abstraction that is used to contain both the data
+required (if any) by an input method and the information required
+to display that data.
+There may be multiple input contexts for one input method.
+The programming interfaces for creating, reading, or modifying
+an input context use a variable argument list.
+The name elements of the argument lists are referred to as <acronym>XIC</acronym> values.
+It is intended that input methods be controlled by these <acronym>XIC</acronym> values.
+As new <acronym>XIC</acronym> values are created,
+they should be registered with the X Consortium.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create an input context, use
+<function>XCreateIC</function>.
+<indexterm significance="preferred"><primary>XCreateIC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreateic'>
+<funcprototype>
+ <funcdef>XIC <function>XCreateIC</function></funcdef>
+ <paramdef>XIM<parameter> im</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>im</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input method.
+<!-- .ds Al \ to set <acronym>XIC</acronym> values -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ ...
+ </term>
+ <listitem>
+ <para>
+Specifies the variable length argument list(Al.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreateIC</function>
+function creates a context within the specified input method.
+</para>
+<para>
+<!-- .LP -->
+Some of the arguments are mandatory at creation time, and
+the input context will not be created if those arguments are not provided.
+The mandatory arguments are the input style and the set of text callbacks
+(if the input style selected requires callbacks).
+All other input context values can be set later.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreateIC</function>
+returns a NULL value if no input context could be created.
+A NULL value could be returned for any of the following reasons:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+A required argument was not set.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A read-only argument was set (for example,
+<symbol>XNFilterEvents</symbol>).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The argument name is not recognized.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The input method encountered an input method implementation-dependent error.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+<function>XCreateIC</function>
+can generate
+<errorname>BadAtom</errorname>,
+<errorname>BadColor</errorname>,
+<errorname>BadPixmap</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To destroy an input context, use
+<function>XDestroyIC</function>.
+<indexterm significance="preferred"><primary>XDestroyIC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdestroyic'>
+<funcprototype>
+ <funcdef>void <function>XDestroyIC</function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<function>XDestroyIC</function>
+destroys the specified input context.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To communicate to and synchronize with input method
+for any changes in keyboard focus from the client side,
+use
+<function>XSetICFocus</function>
+and
+<function>XUnsetICFocus</function>.
+<indexterm significance="preferred"><primary>XSetICFocus</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xseticfocus'>
+<funcprototype>
+ <funcdef>void <function>XSetICFocus</function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetICFocus</function>
+function allows a client to notify an input method that the focus window
+attached to the specified input context has received keyboard focus.
+The input method should take action to provide appropriate feedback.
+Complete feedback specification is a matter of user interface policy.
+</para>
+<para>
+<!-- .LP -->
+Calling
+<function>XSetICFocus</function>
+does not affect the focus window value.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+<indexterm significance="preferred"><primary>XUnsetICFocus</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xunseticfocus'>
+<funcprototype>
+ <funcdef>void <function>XUnsetICFocus</function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUnsetICFocus</function>
+function allows a client to notify an input method that the specified input context
+has lost the keyboard focus and that no more input is expected on the focus window
+attached to that input context.
+The input method should take action to provide appropriate feedback.
+Complete feedback specification is a matter of user interface policy.
+</para>
+<para>
+<!-- .LP -->
+Calling
+<function>XUnsetICFocus</function>
+does not affect the focus window value;
+the client may still receive
+events from the input method that are directed to the focus window.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To reset the state of an input context to its initial state, use
+<function>XmbResetIC</function>
+or
+<function>XwcResetIC</function>.
+<indexterm significance="preferred"><primary>XmbResetIC</primary></indexterm>
+<indexterm significance="preferred"><primary>XwcResetIC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmbresetic'>
+<funcprototype>
+ <funcdef>char *<function>XmbResetIC</function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<funcsynopsis id='xwcresetic'>
+<funcprototype>
+ <funcdef>wchar_t *<function>XwcResetIC</function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+When
+<symbol>XNResetState</symbol>
+is set to
+<symbol>XIMInitialState</symbol>,
+<function>XmbResetIC</function>
+and
+<function>XwcResetIC</function>
+reset an input context to its initial state;
+when
+<symbol>XNResetState</symbol>
+is set to
+<symbol>XIMPreserveState</symbol>,
+the current input context state is preserved.
+In both cases, any input pending on that context is deleted.
+The input method is required to clear the preedit area, if any,
+and update the status accordingly.
+Calling
+<function>XmbResetIC</function>
+or
+<function>XwcResetIC</function>
+does not change the focus.
+</para>
+<para>
+<!-- .LP -->
+The return value of
+<function>XmbResetIC</function>
+is its current preedit string as a multibyte string.
+If there is any preedit text drawn or visible to the user,
+then these procedures must return a non-NULL string.
+If there is no visible preedit text,
+then it is input method implementation-dependent
+whether these procedures return a non-NULL string or NULL.
+</para>
+<para>
+<!-- .LP -->
+The client should free the returned string by calling
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To get the input method associated with an input context, use
+<function>XIMOfIC</function>.
+<indexterm significance="preferred"><primary>XIMOfIC</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='ximofic'>
+<funcprototype>
+ <funcdef>XIM <function>XIMOfIC</function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XIMOfIC</function>
+function returns the input method associated with the specified input context.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+Xlib provides two functions for setting and reading <acronym>XIC</acronym> values, respectively,
+<function>XSetICValues</function>
+and
+<function>XGetICValues</function>.
+Both functions have a variable-length argument list.
+In that argument list, any <acronym>XIC</acronym> value's name must be denoted
+with a character string using the X Portable Character Set.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set <acronym>XIC</acronym> values, use
+<function>XSetICValues</function>.
+<indexterm significance="preferred"><primary>XSetICValues</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xseticvalues'>
+<funcprototype>
+ <funcdef>char *<function>XSetICValues</function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+<!-- .ds Al \ to set <acronym>XIC</acronym> values -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ ...
+ </term>
+ <listitem>
+ <para>
+Specifies the variable length argument list(Al.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetICValues</function>
+function returns NULL if no error occurred;
+otherwise,
+it returns the name of the first argument that could not be set.
+An argument might not be set for any of the following reasons:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The argument is read-only (for example,
+<symbol>XNFilterEvents</symbol>).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The argument name is not recognized.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+An implementation-dependent error occurs.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Each value to be set must be an appropriate datum,
+matching the data type imposed by the semantics of the argument.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetICValues</function>
+can generate
+<errorname>BadAtom</errorname>,
+<errorname>BadColor</errorname>,
+<errorname>BadCursor</errorname>,
+<errorname>BadPixmap</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain <acronym>XIC</acronym> values, use
+<function>XGetICValues</function>.
+<indexterm significance="preferred"><primary>XGetICValues</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgeticvalues'>
+<funcprototype>
+ <funcdef>char *<function>XGetICValues</function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+<!-- .ds Al \ to get XIC values -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ ...
+ </term>
+ <listitem>
+ <para>
+Specifies the variable length argument list(Al.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetICValues</function>
+function returns NULL if no error occurred; otherwise,
+it returns the name of the first argument that could not be obtained.
+An argument could not be obtained for any of the following reasons:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The argument name is not recognized.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The input method encountered an implementation-dependent error.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+Each IC attribute value argument (following a name) must point to
+a location where the IC value is to be stored.
+That is, if the IC value is of type T,
+the argument must be of type T*.
+If T itself is a pointer type,
+then
+<function>XGetICValues</function>
+allocates memory to store the actual data,
+and the client is responsible for freeing this data by calling
+<function>XFree</function>
+with the returned pointer.
+The exception to this rule is for an IC value of type
+<type>XVaNestedList</type>
+(for preedit and status attributes).
+In this case, the argument must also be of type
+<type>XVaNestedList</type>.
+Then, the rule of changing type T to T* and freeing the allocated data
+applies to each element of the nested list.
+</para>
+</sect2>
+<sect2 id="Input_Context_Values">
+<title>Input Context Values</title>
+<!-- .XS -->
+<!-- (SN Input Context Values -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The following tables describe how <acronym>XIC</acronym> values are interpreted
+by an input method depending on the input style chosen by the
+user.
+</para>
+<para>
+<!-- .LP -->
+The first column lists the <acronym>XIC</acronym> values.
+The second column indicates which values are involved in affecting,
+negotiating, and setting the geometry of the input method windows.
+The subentries under the third column indicate the different
+input styles that are supported.
+Each of these columns indicates how each of the <acronym>XIC</acronym> values
+are treated by that input style.
+</para>
+<para>
+<!-- .LP -->
+The following keys apply to these tables.
+</para>
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <thead>
+ <row>
+ <entry>Key</entry>
+ <entry>Explanation</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>C</entry>
+ <entry>This value must be set with <function>XCreateIC</function>.</entry>
+ </row>
+ <row>
+ <entry>D</entry>
+ <entry>This value may be set using
+ <function>XCreateIC</function>.>
+ If it is not set,>
+ a default is provided.</entry>
+ </row>
+ <row>
+ <entry>G</entry>
+ <entry>This value may be read using
+ <function>XGetICValues</function>.</entry>
+ </row>
+ <row>
+ <entry>GN</entry>
+ <entry>This value may cause geometry negotiation when its value is set by means of
+ <function>XCreateIC</function>
+ or
+ <function>XSetICValues</function>.</entry>
+ </row>
+ <row>
+ <entry>GR</entry>
+ <entry>This value will be the response of the input method when any
+ GN value is changed.</entry>
+ </row>
+ <row>
+ <entry>GS</entry>
+ <entry>This value will cause the geometry of the input method window to be set.</entry>
+ </row>
+ <row>
+ <entry>O</entry>
+ <entry>This value must be set once and only once.
+ It need not be set at create time.</entry>
+ </row>
+ <row>
+ <entry>S</entry>
+ <entry>This value may be set with
+ <function>XSetICValues</function>.</entry>
+ </row>
+ <row>
+ <entry>Ignored</entry>
+ <entry>This value is ignored by the input method for the given input style.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<!-- .LP -->
+<informaltable>
+ <tgroup cols='7' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <colspec colname='c3'/>
+ <colspec colname='c4'/>
+ <colspec colname='c5'/>
+ <colspec colname='c6'/>
+ <colspec colname='c7'/>
+ <tbody>
+ <row>
+ <entry><acronym>XIC</acronym> Value</entry>
+ <entry>Geometry Mangement</entry>
+ <entry>Preedit Callback</entry>
+ <entry>Preedit Position</entry>
+ <entry>Input Style Preedit Area</entry>
+ <entry>Preedit Nothing</entry>
+ <entry>Preedit None</entry>
+ </row>
+ <row>
+ <entry>Input Style</entry>
+ <entry></entry>
+ <entry>C-G</entry>
+ <entry>C-G</entry>
+ <entry>C-G</entry>
+ <entry>C-G</entry>
+ <entry>C-G</entry>
+ </row>
+ <row>
+ <entry>Client Window</entry>
+ <entry></entry>
+ <entry>O-G</entry>
+ <entry>O-G</entry>
+ <entry>O-G</entry>
+ <entry>O-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Focus Window</entry>
+ <entry>GN</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Resource Name</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Resource Class</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Geometry Callback</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Filter Events</entry>
+ <entry></entry>
+ <entry>G</entry>
+ <entry>G</entry>
+ <entry>G</entry>
+ <entry>G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Destroy Callback</entry>
+ <entry></entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ </row>
+ <row>
+ <entry>String Conversion Callback</entry>
+ <entry></entry>
+ <entry>S-G</entry>
+ <entry>S-G</entry>
+ <entry>S-G</entry>
+ <entry>S-G</entry>
+ <entry>S-G</entry>
+ </row>
+ <row>
+ <entry>String Conversion</entry>
+ <entry></entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ </row>
+ <row>
+ <entry>Reset State</entry>
+ <entry></entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>HotKey</entry>
+ <entry></entry>
+ <entry>S-G</entry>
+ <entry>S-G</entry>
+ <entry>S-G</entry>
+ <entry>S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>HotKeyState</entry>
+ <entry></entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry><function>Preedit</function></entry>
+ </row>
+ <row>
+ <entry>Area</entry>
+ <entry>GS</entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Area Needed</entry>
+ <entry>GN-GR</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ <entry>S-G</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Spot Location</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Colormap</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Foreground</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Background</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Background Pixmap</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Font Set</entry>
+ <entry>GN</entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Line Spacing</entry>
+ <entry>GN</entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Cursor</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Preedit State</entry>
+ <entry></entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Preedit State Notify Callback</entry>
+ <entry></entry>
+ <entry>S-G</entry>
+ <entry>S-G</entry>
+ <entry>S-G</entry>
+ <entry>S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Preedit Callbacks</entry>
+ <entry></entry>
+ <entry>C-S-G</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<!-- .LP -->
+<informaltable>
+ <tgroup cols='6' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <colspec colname='c3'/>
+ <colspec colname='c4'/>
+ <colspec colname='c5'/>
+ <colspec colname='c6'/>
+ <thead>
+ <row>
+ <entry><acronym>XIC</acronym> Value</entry>
+ <entry>Geomentry Management</entry>
+ <entry>Status Callback</entry>
+ <entry>Status Area</entry>
+ <entry>Status Nothing</entry>
+ <entry>Status None</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>Input Style</entry>
+ <entry></entry>
+ <entry>C-G</entry>
+ <entry>C-G</entry>
+ <entry>C-G</entry>
+ <entry>C-G</entry>
+ </row>
+ <row>
+ <entry>Client Window</entry>
+ <entry></entry>
+ <entry>O-G</entry>
+ <entry>O-G</entry>
+ <entry>O-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Focus Window</entry>
+ <entry>GN</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Resource Name</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Resource Class</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Geometry Callback</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Filter Events</entry>
+ <entry></entry>
+ <entry>G</entry>
+ <entry>G</entry>
+ <entry>G</entry>
+ <entry>G</entry>
+ </row>
+ <row>
+ <entry><type>Status</type></entry>
+ </row>
+ <row>
+ <entry>Area</entry>
+ <entry>GS</entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Area Needed</entry>
+ <entry>GN-GR</entry>
+ <entry>Ignored</entry>
+ <entry>S-G</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Colormap</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Foreground</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Background</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Background Pixmap</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Font Set</entry>
+ <entry>GN</entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Line Spacing</entry>
+ <entry>GN</entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Cursor</entry>
+ <entry></entry>
+ <entry>Ignored</entry>
+ <entry>D-S-G</entry>
+ <entry>D-S-G</entry>
+ <entry>Ignored</entry>
+ </row>
+ <row>
+ <entry>Status Callbacks</entry>
+ <entry></entry>
+ <entry>C-S-G</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ <entry>Ignored</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+<sect3 id="Input_Style">
+<title>Input Style</title>
+<!-- .XS -->
+<!-- (SN Input Style -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNInputStyle</symbol>
+argument specifies the input style to be used.
+The value of this argument must be one of the values returned by the
+<function>XGetIMValues</function>
+function with the
+<symbol>XNQueryInputStyle</symbol>
+argument specified in the supported_styles list.
+</para>
+<para>
+<!-- .LP -->
+Note that this argument must be set at creation time
+and cannot be changed.
+</para>
+</sect3>
+<sect3 id="Client_Window">
+<title>Client Window</title>
+<!-- .XS -->
+<!-- (SN Client Window -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNClientWindow</primary></indexterm>
+The
+<symbol>XNClientWindow</symbol>
+argument specifies to the input method the client window in
+which the input method
+can display data or create subwindows.
+Geometry values for input method areas are given with respect to the client
+window.
+Dynamic change of client window is not supported.
+This argument may be set only once and
+should be set before any input is done using this input context.
+If it is not set,
+the input method may not operate correctly.
+</para>
+<para>
+<!-- .LP -->
+If an attempt is made to set this value a second time with
+<function>XSetICValues</function>,
+the string
+<symbol>XNClientWindow</symbol>
+will be returned by
+<function>XSetICValues</function>,
+and the client window will not be changed.
+</para>
+<para>
+<!-- .LP -->
+If the client window is not a valid window ID on the display
+attached to the input method,
+a
+<errorname>BadWindow</errorname>
+error can be generated when this value is used by the input method.
+</para>
+</sect3>
+<sect3 id="Focus_Window">
+<title>Focus Window</title>
+<!-- .XS -->
+<!-- (SN Focus Window -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNFocusWindow</primary></indexterm>
+The
+<symbol>XNFocusWindow</symbol>
+argument specifies the focus window.
+The primary purpose of the
+<symbol>XNFocusWindow</symbol>
+is to identify the window that will receive the key event when input
+is composed.
+In addition, the input method may possibly affect the focus window
+as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Select events on it
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Send events to it
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Modify its properties
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Grab the keyboard within that window
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The associated value must be of type
+<type>Window</type>.
+If the focus window is not a valid window ID on the display
+attached to the input method,
+a
+<errorname>BadWindow</errorname>
+error can be generated when this value is used by the input method.
+</para>
+<para>
+<!-- .LP -->
+When this <acronym>XIC</acronym> value is left unspecified,
+the input method will use the client window as the default focus window.
+</para>
+</sect3>
+<sect3 id="Resource_Name_and_Class_b">
+<title>Resource Name and Class</title>
+<!-- .XS -->
+<!-- (SN Resource Name and Class -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNResourceName</primary></indexterm>
+<indexterm significance="preferred"><primary>XNResourceClass</primary></indexterm>
+The
+<symbol>XNResourceName</symbol>
+and
+<symbol>XNResourceClass</symbol>
+arguments are strings that specify the full name and class
+used by the client to obtain resources for the client window.
+These values should be used as prefixes for name and class
+when looking up resources that may vary according to the input context.
+If these values are not set,
+the resources will not be fully specified.
+</para>
+<para>
+<!-- .LP -->
+It is not intended that values that can be set as <acronym>XIC</acronym> values be
+set as resources.
+</para>
+</sect3>
+<sect3 id="Geometry_Callback">
+<title>Geometry Callback</title>
+<!-- .XS -->
+<!-- (SN Geometry Callback -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNGeometryCallback</primary></indexterm>
+The
+<symbol>XNGeometryCallback</symbol>
+argument is a structure of type
+<structname>XIMCallback</structname>
+(see section 13.5.6.13.12).
+</para>
+<para>
+<!-- .LP -->
+The
+<symbol>XNGeometryCallback</symbol>
+argument specifies the geometry callback that a client can set.
+This callback is not required for correct operation of either
+an input method or a client.
+It can be set for a client whose user interface policy permits
+an input method to request the dynamic change of that input
+method's window.
+An input method that does dynamic change will need to filter any
+events that it uses to initiate the change.
+</para>
+</sect3>
+<sect3 id="Filter_Events">
+<title>Filter Events</title>
+<!-- .XS -->
+<!-- (SN Filter Events -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNFilterEvents</primary></indexterm>
+The
+<symbol>XNFilterEvents</symbol>
+argument returns the event mask that an input method needs
+to have selected for.
+The client is expected to augment its own event mask
+for the client window with this one.
+</para>
+<para>
+<!-- .LP -->
+This argument is read-only, is set by the input method at create time,
+and is never changed.
+</para>
+<para>
+<!-- .LP -->
+The type of this argument is
+<type>unsigned</type>
+<type>long</type>.
+Setting this value will cause an error.
+</para>
+</sect3>
+<sect3 id="Destroy_Callback_b">
+<title>Destroy Callback</title>
+<!-- .XS -->
+<!-- (SN Destroy Callback -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNDestroyCallback</symbol>
+argument is a pointer to a structure of type
+<structname>XIMCallback</structname>
+(see section 13.5.6.13.12). This callback is triggered when the input method
+stops its service for any reason; for example, when a connection to an IM
+server is broken. After the destroy callback is called,
+the input context is destroyed and the input method is closed.
+Therefore, the client should not call
+<function>XDestroyIC</function>
+and
+<function>XCloseIM</function>.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+<sect3 id="String_Conversion_Callback">
+<title>String Conversion Callback</title>
+<!-- .XS -->
+<!-- (SN String Conversion Callback -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNStringConversionCallback</symbol>
+argument is a structure of type
+<structname>XIMCallback</structname>
+(see section 13.5.6.13.12).
+</para>
+<para>
+<!-- .LP -->
+The
+<symbol>XNStringConversionCallback</symbol>
+argument specifies a string conversion callback. This callback
+is not required for correct operation of
+either the input method or the client. It can be set by a client
+to support string conversions that may be requested
+by the input method. An input method that does string conversions
+will filter any events that it uses to initiate the conversion.
+</para>
+<para>
+<!-- .LP -->
+Because this <acronym>XIC</acronym> value is optional, a client should call
+<function>XGetIMValues</function>
+with argument
+<symbol>XNQueryICValuesList</symbol>
+before using this argument.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+<sect3 id="String_Conversion_">
+<title>String Conversion </title>
+<!-- .XS -->
+<!-- (SN String Conversion -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNStringConversion</symbol>
+argument is a structure of type
+<structname>XIMStringConversionText</structname>.
+</para>
+<para>
+<!-- .LP -->
+The
+<symbol>XNStringConversion</symbol>
+argument specifies the string to be converted by an input method.
+This argument is not required for correct operation of either
+the input method or the client.
+</para>
+<para>
+<!-- .LP -->
+String conversion facilitates the manipulation of text independent
+of preediting.
+It is essential for some input methods and clients to manipulate
+text by performing context-sensitive conversion,
+reconversion, or transliteration conversion on it.
+</para>
+<para>
+<!-- .LP -->
+Because this <acronym>XIC</acronym> value is optional, a client should call
+<function>XGetIMValues</function>
+with argument
+<symbol>XNQueryICValuesList</symbol>
+before using this argument.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XIMStringConversionText</structname>
+structure is defined as follows:
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<literallayout class="monospaced">
+
+typedef struct _XIMStringConversionText {
+ unsigned short length;
+ XIMStringConversionFeedback *feedback;
+ Bool encoding_is_wchar;
+ union {
+ char *mbs;
+ wchar_t *wcs;
+ } string;
+} XIMStringConversionText;
+
+typedef unsigned long XIMStringConversionFeedback;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The feedback member is reserved for future use. The text to be
+converted is defined by the string and length members. The length
+is indicated in characters. To prevent the library from freeing memory
+pointed to by an uninitialized pointer, the client should set the feedback
+element to NULL.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+<sect3 id="Reset_State">
+<title>Reset State</title>
+<!-- .XS -->
+<!-- (SN Reset State -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNResetState</symbol>
+argument specifies the state the input context will return to after calling
+<function>XmbResetIC</function>
+or
+<function>XwcResetIC</function>.
+</para>
+<para>
+<!-- .LP -->
+The <acronym>XIC</acronym> state may be set to its initial state, as specified by the
+<symbol>XNPreeditState</symbol>
+value when
+<function>XCreateIC</function>
+was called, or it may be set to preserve the current state.
+</para>
+<para>
+<!-- .LP -->
+The valid masks for
+<type>XIMResetState</type>
+are as follows:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XIMInitialState</primary></indexterm>
+<indexterm significance="preferred"><primary>XINPreserveState</primary></indexterm>
+<!-- .sM -->
+</para>
+<literallayout class="monospaced">
+typedef unsigned long XIMResetState;
+
+#define XIMInitialState (1L)
+#define XIMPreserveState (1L&lt;&lt;1)
+
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If
+<symbol>XIMInitialState</symbol>
+is set, then
+<function>XmbResetIC</function>
+and
+<function>XwcResetIC</function>
+will return to the initial
+<symbol>XNPreeditState</symbol>
+state of the <acronym>XIC</acronym>.
+</para>
+<para>
+<!-- .LP -->
+If
+<symbol>XIMPreserveState</symbol>
+is set, then
+<function>XmbResetIC</function>
+and
+<function>XwcResetIC</function>
+will preserve the current state of the <acronym>XIC</acronym>.
+</para>
+<para>
+<!-- .LP -->
+If
+<symbol>XNResetState</symbol>
+is left unspecified, the default is
+<symbol>XIMInitialState</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<type>XIMResetState</type>
+values other than those specified above will default to
+<symbol>XIMInitialState</symbol>.
+</para>
+<para>
+<!-- .LP -->
+Because this <acronym>XIC</acronym> value is optional, a client should call
+<function>XGetIMValues</function>
+with argument
+<symbol>XNQueryICValuesList</symbol>
+before using this argument.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+<sect3 id="Hot_Keys_b">
+<title>Hot Keys</title>
+<!-- .XS -->
+<!-- (SN Hot Keys -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNHotKey</symbol>
+argument specifies the hot key list to the <acronym>XIC</acronym>.
+The hot key list is a pointer to the structure of type
+<structname>XIMHotKeyTriggers</structname>,
+which specifies the key events that must be received
+without any interruption of the input method.
+For the hot key list set with this argument to be utilized, the client
+must also set
+<symbol>XNHotKeyState</symbol>
+to
+<symbol>XIMHotKeyStateON</symbol>.
+</para>
+<para>
+<!-- .LP -->
+Because this <acronym>XIC</acronym> value is optional, a client should call
+<function>XGetIMValues</function>
+with argument
+<symbol>XNQueryICValuesList</symbol>
+before using this functionality.
+</para>
+<para>
+<!-- .LP -->
+The value of the argument is a pointer to a structure of type
+<structname>XIMHotKeyTriggers</structname>.
+</para>
+<para>
+<!-- .LP -->
+If an event for a key in the hot key list is found, then the process will
+receive the event and it will be processed inside the client.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ KeySym keysym;
+ unsigned int modifier;
+ unsigned int modifier_mask;
+} XIMHotKeyTrigger;
+
+typedef struct {
+ int num_hot_key;
+ XIMHotKeyTrigger *key;
+} XIMHotKeyTriggers;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+</para>
+<para>
+<!-- .LP -->
+The combination of modifier and modifier_mask are used to represent one of
+three states for each modifier:
+either the modifier must be on, or the modifier must be off, or the modifier
+is a ``don't care'' - it may be on or off.
+When a modifier_mask bit is set to 0, the state of the associated modifier
+is ignored when evaluating whether the key is hot or not.
+</para>
+
+<informaltable>
+ <tgroup cols='3' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <colspec colname='c3'/>
+ <thead>
+ <row>
+ <entry>Modifier Bit</entry>
+ <entry>Mask Bit</entry>
+ <entry>Meaning</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>0</entry>
+ <entry>1</entry>
+ <entry>The modifier must be off.</entry>
+ </row>
+ <row>
+ <entry>1</entry>
+ <entry>1</entry>
+ <entry>The modifier must be on.</entry>
+ </row>
+ <row>
+ <entry>n/a</entry>
+ <entry>0</entry>
+ <entry>Do not care if the modifier is on or off.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+</sect3>
+<sect3 id="Hot_Key_State">
+<title>Hot Key State</title>
+<!-- .XS -->
+<!-- (SN Hot Key State -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNHotKeyState</symbol>
+argument specifies the hot key state of the input method.
+This is usually used to switch the input method between hot key
+operation and normal input processing.
+</para>
+<para>
+<!-- .LP -->
+The value of the argument is a pointer to a structure of type
+XIMHotKeyState .
+</para>
+<literallayout class="monospaced">
+typedef unsigned long XIMHotKeyState;
+
+#define XIMHotKeyStateON (0x0001L)
+#define XIMHotKeyStateOFF (0x0002L)
+
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+</para>
+<para>
+<!-- .LP -->
+If not specified, the default is
+<symbol>XIMHotKeyStateOFF</symbol>.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+<sect3 id="Preedit_and_Status_Attributes">
+<title>Preedit and Status Attributes</title>
+<!-- .XS -->
+<!-- (SN Preedit and Status Attributes -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNPreeditAttributes</primary></indexterm>
+<indexterm significance="preferred"><primary>XNStatusAttributes</primary></indexterm>
+The
+<symbol>XNPreeditAttributes</symbol>
+and
+<symbol>XNStatusAttributes</symbol>
+arguments specify to an input method the attributes to be used for the
+preedit and status areas,
+if any.
+Those attributes are passed to
+<function>XSetICValues</function>
+or
+<function>XGetICValues</function>
+as a nested variable-length list.
+The names to be used in these lists are described in the following sections.
+</para>
+<sect4 id="Area">
+<title>Area</title>
+<!-- .XS -->
+<!-- (SN Area -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNArea</primary></indexterm>
+The value of the
+<symbol>XNArea</symbol>
+argument must be a pointer to a structure of type
+<structname>XRectangle</structname>.
+The interpretation of the
+<symbol>XNArea</symbol>
+argument is dependent on the input method style that has been set.
+</para>
+<para>
+<!-- .LP -->
+If the input method style is
+<symbol>XIMPreeditPosition</symbol>,
+<symbol>XNArea</symbol>
+specifies the clipping region within which preediting will take place.
+If the focus window has been set,
+the coordinates are assumed to be relative to the focus window.
+Otherwise, the coordinates are assumed to be relative to the client window.
+If neither has been set,
+the results are undefined.
+</para>
+<para>
+<!-- .LP -->
+If
+<symbol>XNArea</symbol>
+is not specified, is set to NULL, or is invalid,
+the input method will default the clipping region
+to the geometry of the
+<symbol>XNFocusWindow</symbol>.
+If the area specified is NULL or invalid,
+the results are undefined.
+</para>
+<para>
+<!-- .LP -->
+If the input style is
+<symbol>XIMPreeditArea</symbol>
+or
+<symbol>XIMStatusArea</symbol>,
+<symbol>XNArea</symbol>
+specifies the geometry provided by the client to the input method.
+The input method may use this area to display its data,
+either preedit or status depending on the area designated.
+The input method may create a window as a child of the client window
+with dimensions that fit the
+<symbol>XNArea</symbol>.
+The coordinates are relative to the client window.
+If the client window has not been set yet,
+the input method should save these values
+and apply them when the client window is set.
+If
+<symbol>XNArea</symbol>
+is not specified, is set to NULL, or is invalid,
+the results are undefined.
+</para>
+</sect4>
+<sect4 id="Area_Needed">
+<title>Area Needed</title>
+<!-- .XS -->
+<!-- (SN Area Needed -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNAreaNeeded</primary></indexterm>
+When set, the
+<symbol>XNAreaNeeded</symbol>
+argument specifies the geometry suggested by the client for this area
+(preedit or status).
+The value associated with the argument must be a pointer to a
+structure of type
+<structname>XRectangle</structname>.
+Note that the x, y values are not used
+and that nonzero values for width or height are the constraints
+that the client wishes the input method to respect.
+</para>
+<para>
+<!-- .LP -->
+When read, the
+<symbol>XNAreaNeeded</symbol>
+argument specifies the preferred geometry desired by the input method
+for the area.
+</para>
+<para>
+<!-- .LP -->
+This argument is only valid if the input style is
+<symbol>XIMPreeditArea</symbol>
+or
+<symbol>XIMStatusArea</symbol>.
+It is used for geometry negotiation between the client and the input method
+and has no other effect on the input method
+(see section 13.5.1.5).
+</para>
+</sect4>
+<sect4 id="Spot_Location">
+<title>Spot Location</title>
+<!-- .XS -->
+<!-- (SN Spot Location -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNSpotLocation</primary></indexterm>
+The
+<symbol>XNSpotLocation</symbol>
+argument specifies to the input method the coordinates of the spot
+to be used by an input method executing with
+<symbol>XNInputStyle</symbol>
+set to
+<symbol>XIMPreeditPosition</symbol>.
+When specified to any input method other than
+<symbol>XIMPreeditPosition</symbol>,
+this <acronym>XIC</acronym> value is ignored.
+</para>
+<para>
+<!-- .LP -->
+The x coordinate specifies the position where the next character
+would be inserted.
+The y coordinate is the position of the baseline used
+by the current text line in the focus window.
+The x and y coordinates are relative to the focus window, if it has been set;
+otherwise, they are relative to the client window.
+If neither the focus window nor the client window has been set,
+the results are undefined.
+</para>
+<para>
+<!-- .LP -->
+The value of the argument is a pointer to a structure of type
+<structname>XPoint</structname>.
+</para>
+</sect4>
+<sect4 id="Colormap">
+<title>Colormap</title>
+<!-- .XS -->
+<!-- (SN Colormap -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Two different arguments can be used to indicate what colormap the input method
+should use to allocate colors, a colormap ID, or a standard colormap name.
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNColormap</primary></indexterm>
+The
+<symbol>XNColormap</symbol>
+argument is used to specify a colormap ID.
+The argument value is of type
+<type>Colormap</type>.
+An invalid argument may generate a
+<errorname>BadColor</errorname>
+error when it is used by the input method.
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNStdColormap</primary></indexterm>
+The
+<symbol>XNStdColormap</symbol>
+argument is used to indicate the name of the standard colormap
+in which the input method should allocate colors.
+The argument value is an
+<type>Atom</type>
+that should be a valid atom for calling
+<function>XGetRGBColormaps</function>.
+An invalid argument may generate a
+<errorname>BadAtom</errorname>
+error when it is used by the input method.
+</para>
+<para>
+<!-- .LP -->
+If the colormap is left unspecified,
+the client window colormap becomes the default.
+</para>
+</sect4>
+<sect4 id="Foreground_and_Background">
+<title>Foreground and Background</title>
+<!-- .XS -->
+<!-- (SN Foreground and Background -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNForeground</primary></indexterm>
+<indexterm significance="preferred"><primary>XNBackground</primary></indexterm>
+The
+<symbol>XNForeground</symbol>
+and
+<symbol>XNBackground</symbol>
+arguments specify the foreground and background pixel, respectively.
+The argument value is of type
+<type>unsigned</type>
+<type>long</type>.
+It must be a valid pixel in the input method colormap.
+</para>
+<para>
+<!-- .LP -->
+If these values are left unspecified,
+the default is determined by the input method.
+</para>
+</sect4>
+<sect4 id="Background_Pixmap">
+<title>Background Pixmap</title>
+<!-- .XS -->
+<!-- (SN Background Pixmap -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNBackgroundPixmap</symbol>
+argument specifies a background pixmap to be used as the background of the
+window.
+The value must be of type
+<type>Pixmap</type>.
+An invalid argument may generate a
+<errorname>BadPixmap</errorname>
+error when it is used by the input method.
+</para>
+<para>
+<!-- .LP -->
+If this value is left unspecified,
+the default is determined by the input method.
+</para>
+</sect4>
+<sect4 id="Font_Set">
+<title>Font Set</title>
+<!-- .XS -->
+<!-- (SN Font Set -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNFontSet</primary></indexterm>
+The
+<symbol>XNFontSet</symbol>
+argument specifies to the input method what font set is to be used.
+The argument value is of type
+<type>XFontSet</type>.
+</para>
+<para>
+<!-- .LP -->
+If this value is left unspecified,
+the default is determined by the input method.
+</para>
+</sect4>
+<sect4 id="Line_Spacing">
+<title>Line Spacing</title>
+<!-- .XS -->
+<!-- (SN Line Spacing -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNLineSpace</symbol>
+argument specifies to the input method what line spacing is to be used
+in the preedit window if more than one line is to be used.
+This argument is of type
+<type>int</type>.
+</para>
+<para>
+<!-- .LP -->
+If this value is left unspecified,
+the default is determined by the input method.
+</para>
+</sect4>
+<sect4 id="Cursor">
+<title>Cursor</title>
+<!-- .XS -->
+<!-- (SN Cursor -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XNCursor</primary></indexterm>
+The
+<symbol>XNCursor</symbol>
+argument specifies to the input method what cursor is to be used
+in the specified window.
+This argument is of type
+<type>Cursor</type>.
+</para>
+<para>
+<!-- .LP -->
+An invalid argument may generate a
+<errorname>BadCursor</errorname>
+error when it is used by the input method.
+If this value is left unspecified,
+the default is determined by the input method.
+</para>
+</sect4>
+<sect4 id="Preedit_State">
+<title>Preedit State</title>
+<!-- .XS -->
+<!-- (SN Preedit State -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<symbol>XNPreeditState</symbol>
+argument specifies the state of input preediting for the input method.
+Input preediting can be on or off.
+</para>
+<para>
+<!-- .LP -->
+The valid mask names for
+<symbol>XNPreeditState</symbol>
+are as follows:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XIMPreeditUnknown</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPreeditEnable</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPreeditDisable</primary></indexterm>
+<!-- .sM -->
+</para>
+<!-- .LP -->
+<literallayout class="monospaced">
+typedef unsigned long XIMPreeditState;
+
+#define XIMPreeditUnknown 0L
+#define XIMPreeditEnable 1L
+#define XIMPreeditDisable (1L&lt;&lt;1)
+
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If a value of
+<symbol>XIMPreeditEnable</symbol>
+is set, then input preediting is turned on by the input method.
+</para>
+<para>
+<!-- .LP -->
+If a value of
+<symbol>XIMPreeditDisable</symbol>
+is set, then input preediting is turned off by the input method.
+</para>
+<para>
+<!-- .LP -->
+If
+<symbol>XNPreeditState</symbol>
+is left unspecified, then the state will be implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+When
+<symbol>XNResetState</symbol>
+is set to
+<symbol>XIMInitialState</symbol>,
+the
+<symbol>XNPreeditState</symbol>
+value specified at the creation time will be reflected as the initial state for
+<function>XmbResetIC</function>
+and
+<function>XwcResetIC</function>.
+</para>
+<para>
+<!-- .LP -->
+Because this <acronym>XIC</acronym> value is optional, a client should call
+<function>XGetIMValues</function>
+with argument
+<symbol>XNQueryICValuesList</symbol>
+before using this argument.
+</para>
+</sect4>
+<sect4 id="Preedit_State_Notify_Callback">
+<title>Preedit State Notify Callback</title>
+<!-- .XS -->
+<!-- (SN Preedit State Notify Callback -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The preedit state notify callback is triggered by the input method
+when the preediting state has changed.
+The value of the
+<symbol>XNPreeditStateNotifyCallback</symbol>
+argument is a pointer to a structure of type
+<structname>XIMCallback</structname>.
+The generic prototype is as follows:
+<indexterm significance="preferred"><primary>PreeditStateNotifyCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='preeditstatenotifycallback'>
+<funcprototype>
+ <funcdef>void <function><replaceable>PreeditStateNotifyCallback</replaceable></function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XIMPreeditStateNotifyCallbackStruct<parameter> *call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the current preedit state.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<structname>XIMPreeditStateNotifyCallbackStruct</structname>
+structure is defined as follows:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XIMPreeditStateNotifyCallbackStruct</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct _XIMPreeditStateNotifyCallbackStruct {
+ XIMPreeditState state;
+} XIMPreeditStateNotifyCallbackStruct;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+</para>
+<para>
+<!-- .LP -->
+Because this <acronym>XIC</acronym> value is optional, a client should call
+<function>XGetIMValues</function>
+with argument
+<symbol>XNQueryICValuesList</symbol>
+before using this argument.
+</para>
+</sect4>
+<sect4 id="Preedit_and_Status_Callbacks">
+<title>Preedit and Status Callbacks</title>
+<!-- .XS -->
+<!-- (SN Preedit and Status Callbacks -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+A client that wants to support the input style
+<symbol>XIMPreeditCallbacks</symbol>
+must provide a set of preedit callbacks to the input method.
+The set of preedit callbacks is as follows:
+</para>
+<indexterm significance="preferred"><primary>XNPreeditStartCallback</primary></indexterm>
+<indexterm significance="preferred"><primary>XNPreeditDoneCallback</primary></indexterm>
+<indexterm significance="preferred"><primary>XNPreeditDrawCallback</primary></indexterm>
+<indexterm significance="preferred"><primary>XNPreeditCaretCallback</primary></indexterm>
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <tbody>
+ <row>
+ <entry><symbol>XNPreeditStartCallback</symbol></entry>
+ <entry>This is called when the input method starts preedit.</entry>
+ </row>
+ <row>
+ <entry><symbol>XNPreeditDoneCallback</symbol></entry>
+ <entry>This is called when the input method stops preedit.</entry>
+ </row>
+ <row>
+ <entry><symbol>XNPreeditDrawCallback</symbol></entry>
+ <entry>This is called when a number of preedit keystrokes should be echoed.</entry>
+ </row>
+ <row>
+ <entry><symbol>XNPreeditCaretCallback</symbol></entry>
+ <entry>This is called to move the text insertion point within the preedit string.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+A client that wants to support the input style
+<symbol>XIMStatusCallbacks</symbol>
+must provide a set of status callbacks to the input method.
+The set of status callbacks is as follows:
+</para>
+
+<indexterm significance="preferred"><primary>XNStatusStartCallback</primary></indexterm>
+<indexterm significance="preferred"><primary>XNStatusDoneCallback</primary></indexterm>
+<indexterm significance="preferred"><primary>XNStatusDrawCallback</primary></indexterm>
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <tbody>
+ <row>
+ <entry><symbol>XNStatusStartCallback</symbol></entry>
+ <entry>This is called when the input method initializes the status area.</entry>
+ </row>
+ <row>
+ <entry><symbol>XNStatusDoneCallback</symbol></entry>
+ <entry>This is called when the input method no longer needs the status area.</entry>
+ </row>
+ <row>
+ <entry><symbol>XNStatusDrawCallback</symbol></entry>
+ <entry>This is called when updating of the status area is required.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+<para>
+<!-- .LP -->
+The value of any status or preedit argument is a pointer
+to a structure of type
+<structname>XIMCallback</structname>.
+<indexterm significance="preferred"><primary>XIMProc</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMCallback</primary></indexterm>
+<!-- .sM -->
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef void (*XIMProc)();
+
+typedef struct {
+ XPointer client_data;
+ XIMProc callback;
+} XIMCallback;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Each callback has some particular semantics and will carry the data
+that expresses the environment necessary to the client
+into a specific data structure.
+This paragraph only describes the arguments to be used to set
+the callback.
+</para>
+<para>
+<!-- .LP -->
+Setting any of these values while doing preedit
+may cause unexpected results.
+</para>
+</sect4>
+</sect3>
+</sect2>
+<sect2 id="Input_Method_Callback_Semantics">
+<title>Input Method Callback Semantics</title>
+<!-- .XS -->
+<!-- (SN Input Method Callback Semantics -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<acronym>XIM</acronym> callbacks are procedures defined by clients or text drawing packages
+that are to be called from the input method when selected events occur.
+Most clients will use a text editing package or a toolkit
+and, hence, will not need to define such callbacks.
+This section defines the callback semantics, when they are triggered,
+and what their arguments are.
+This information is mostly useful for X toolkit implementors.
+</para>
+<para>
+<!-- .LP -->
+Callbacks are mostly provided so that clients (or text editing
+packages) can implement on-the-spot preediting in their own window.
+In that case,
+the input method needs to communicate and synchronize with the client.
+The input method needs to communicate changes in the preedit window
+when it is under control of the client.
+Those callbacks allow the client to initialize the preedit area,
+display a new preedit string,
+move the text insertion point during preedit,
+terminate preedit, or update the status area.
+</para>
+<para>
+<!-- .LP -->
+All callback procedures follow the generic prototype:
+<indexterm significance="preferred"><primary>CallbackPrototype</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>void <function><replaceable>CallbackPrototype</replaceable></function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>SomeType<parameter> call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies data specific to the callback.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The call_data argument is a structure that expresses the arguments needed
+to achieve the semantics;
+that is,
+it is a specific data structure appropriate to the callback.
+In cases where no data is needed in the callback,
+this call_data argument is NULL.
+The client_data argument is a closure that has been initially specified
+by the client when specifying the callback and passed back.
+It may serve, for example, to inherit application context in the callback.
+</para>
+<para>
+<!-- .LP -->
+The following paragraphs describe the programming semantics
+and specific data structure associated with the different reasons.
+</para>
+<sect3 id="Geometry_Callback_b">
+<title>Geometry Callback</title>
+<!-- .XS -->
+<!-- (SN Geometry Callback -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The geometry callback is triggered by the input method
+to indicate that it wants the client to negotiate geometry.
+The generic prototype is as follows:
+<indexterm significance="preferred"><primary>GeometryCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis>
+<funcprototype>
+ <funcdef>void <function><replaceable>GeometryCallback</replaceable></function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XPointer<parameter> call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Not used for this callback and always passed as NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The callback is called with a NULL call_data argument.
+</para>
+</sect3>
+<sect3 id="Destroy_Callback_c">
+<title>Destroy Callback</title>
+<!-- .XS -->
+<!-- (SN Destroy Callback -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The destroy callback is triggered by the input method
+when it stops service for any reason.
+After the callback is invoked, the input context will be freed by Xlib.
+The generic prototype is as follows:
+<indexterm significance="preferred"><primary>DestroyCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='destroycallback_xic'>
+<funcprototype>
+ <funcdef>void <function><replaceable>DestroyCallback</replaceable></function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XPointer<parameter> call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Not used for this callback and always passed as NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The callback is called with a NULL call_data argument.
+</para>
+</sect3>
+<sect3 id="String_Conversion_Callback_b">
+<title>String Conversion Callback</title>
+<!-- .XS -->
+<!-- (SN String Conversion Callback -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The string conversion callback is triggered by the input method
+to request the client to return the string to be converted. The
+returned string may be either a multibyte or wide character string,
+with an encoding matching the locale bound to the input context.
+The callback prototype is as follows:
+<indexterm significance="preferred"><primary>StringConversionCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='stringconversioncallback'>
+<funcprototype>
+ <funcdef>void <function><replaceable>StringConversionCallback</replaceable></function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XIMStringConversionCallbackStruct<parameter> *call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input method.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the amount of the string to be converted.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The callback is passed an
+<structname>XIMStringConversionCallbackStruct</structname>
+structure in the call_data argument.
+The text member is an
+<structname>XIMStringConversionText</structname>
+structure (see section 13.5.6.9) to be filled in by the client
+and describes the text to be sent to the input method.
+The data pointed to by the
+string and feedback elements of the
+<structname>XIMStringConversionText</structname>
+structure will be freed using
+<function>XFree</function>
+by the input method
+after the callback returns. So the client should not point to
+internal buffers that are critical to the client.
+Similarly, because the feedback element is currently reserved for future
+use, the client should set feedback to NULL to prevent the library from
+freeing memory at some random location due to an uninitialized pointer.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XIMStringConversionCallbackStruct</structname>
+structure is defined as follows:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XIMStringConversionCallbackStruct</primary></indexterm>
+<!-- .sM -->
+</para>
+<!-- .LP -->
+<literallayout class="monospaced">
+typedef struct _XIMStringConversionCallbackStruct {
+ XIMStringConversionPosition position;
+ XIMCaretDirection direction;
+ short factor;
+ XIMStringConversionOperation operation;
+ XIMStringConversionText *text;
+} XIMStringConversionCallbackStruct;
+
+typedef short XIMStringConversionPosition;
+
+typedef unsigned short XIMStringConversionOperation;
+
+#define XIMStringConversionSubstitution (0x0001)
+#define XIMStringConversionRetrieval (0x0001)
+
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<type>XIMStringConversionPosition</type>
+specifies the starting position of the string to be returned
+in the
+<structname>XIMStringConversionText</structname>
+structure. The value identifies a position, in units of characters,
+relative to the client's cursor position in the client's buffer.
+</para>
+<para>
+<!-- .LP -->
+The ending position of the text buffer is determined by
+the direction and factor members. Specifically, it is the character position
+relative to the starting point as defined by the
+<structname>XIMCaretDirection</structname>.
+The factor member of
+<structname>XIMStringConversionCallbackStruct</structname>
+specifies the number of
+<structname>XIMCaretDirection</structname>
+positions to be applied. For example, if the direction specifies
+<constant>XIMLineEnd</constant>
+and factor is 1, then all characters from the starting position to
+the end of the current display line are returned. If the direction
+specifies
+<constant>XIMForwardChar</constant>
+or
+<constant>XIMBackwardChar</constant>,
+then the factor specifies a relative position, indicated in characters,
+from the starting position.
+</para>
+<para>
+<!-- .LP -->
+<type>XIMStringConversionOperation</type>
+specifies whether the string to be converted should be
+deleted (substitution) or copied (retrieval) from the client's
+buffer. When the
+<type>XIMStringConversionOperation</type>
+is
+<symbol>XIMStringConversionSubstitution</symbol>,
+the client must delete the string to be converted from its own buffer.
+When the
+<type>XIMStringConversionOperation</type>
+is
+<symbol>XIMStringConversionRetrieval</symbol>,
+the client must not delete the string to be converted from its buffer.
+The substitute operation is typically used for reconversion and
+transliteration conversion,
+while the retrieval operation is typically used for context-sensitive
+conversion.
+</para>
+</sect3>
+<sect3 id="Preedit_State_Callbacks">
+<title>Preedit State Callbacks</title>
+<!-- .XS -->
+<!-- (SN Preedit State Callbacks -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+When the input method turns preediting on or off, a
+<function><replaceable>PreeditStartCallback</replaceable></function>
+or
+<function><replaceable>PreeditDoneCallback</replaceable></function>
+callback is triggered to let the toolkit do the setup
+or the cleanup for the preedit region.
+<indexterm significance="preferred"><primary>PreeditStartCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='preeditstartcallback'>
+<funcprototype>
+ <funcdef>int <function><replaceable>PreeditStartCallback</replaceable></function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XPointer<parameter> call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Not used for this callback and always passed as NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+When preedit starts on the specified input context,
+the callback is called with a NULL call_data argument.
+<function><replaceable>PreeditStartCallback</replaceable></function>
+will return the maximum size of the preedit string.
+A positive number indicates the maximum number of bytes allowed
+in the preedit string,
+and a value of -1 indicates there is no limit.
+<indexterm significance="preferred"><primary>PreeditDoneCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='preeditdonecallback'>
+<funcprototype>
+ <funcdef>void <function><replaceable>PreeditDoneCallback</replaceable></function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XPointer<parameter> call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Not used for this callback and always passed as NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+When preedit stops on the specified input context,
+the callback is called with a NULL call_data argument.
+The client can release the data allocated by
+<function><replaceable>PreeditStartCallback</replaceable></function>.
+</para>
+<para>
+<!-- .LP -->
+<function><replaceable>PreeditStartCallback</replaceable></function>
+should initialize appropriate data needed for
+displaying preedit information and for handling further
+<function><replaceable>PreeditDrawCallback</replaceable></function>
+calls.
+Once
+<function><replaceable>PreeditStartCallback</replaceable></function>
+is called, it will not be called again before
+<function><replaceable>PreeditDoneCallback</replaceable></function>
+has been called.
+</para>
+</sect3>
+<sect3 id="Preedit_Draw_Callback">
+<title>Preedit Draw Callback</title>
+<!-- .XS -->
+<!-- (SN Preedit Draw Callback -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This callback is triggered to draw and insert, delete or replace,
+preedit text in the preedit region.
+The preedit text may include unconverted input text such as Japanese Kana,
+converted text such as Japanese Kanji characters, or characters of both kinds.
+That string is either a multibyte or wide character string,
+whose encoding matches the locale bound to the input context.
+The callback prototype
+is as follows:
+<indexterm significance="preferred"><primary>PreeditDrawCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='preeditdrawcallback'>
+<funcprototype>
+ <funcdef>void <function><replaceable>PreeditDrawCallback</replaceable></function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XIMPreeditDrawCallbackStruct<parameter> *call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the preedit drawing information.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The callback is passed an
+<structname>XIMPreeditDrawCallbackStruct</structname>
+structure in the call_data argument.
+The text member of this structure contains the text to be drawn.
+After the string has been drawn,
+the caret should be moved to the specified location.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XIMPreeditDrawCallbackStruct</structname>
+structure is defined as follows:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XIMPreeditDrawCallbackStruct</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct _XIMPreeditDrawCallbackStruct {
+ int caret; /* Cursor offset within preedit string */
+ int chg_first; /* Starting change position */
+ int chg_length; /* Length of the change in character count */
+ XIMText *text;
+} XIMPreeditDrawCallbackStruct;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The client must keep updating a buffer of the preedit text
+and the callback arguments referring to indexes in that buffer.
+The call_data fields have specific meanings according to the operation,
+as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+To indicate text deletion,
+the call_data member specifies a NULL text field.
+The text to be deleted is then the current text in the buffer
+from position chg_first (starting at zero) on a character length
+of chg_length.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+When text is non-NULL,
+it indicates insertion or replacement of text in the buffer.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The chg_length member
+identifies the number of characters in the current preedit buffer
+that are affected by this call.
+A positive chg_length indicates that chg_length number of characters, starting
+at chg_first, must be deleted or must be replaced by text, whose length is
+specified in the
+<structname>XIMText</structname>
+structure.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A chg_length value of zero indicates that text must be inserted
+right at the position specified by chg_first.
+A value of zero for chg_first specifies the first character in the buffer.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+chg_length and chg_first combine to identify the modification required to
+the preedit buffer; beginning at chg_first, replace chg_length number of
+characters with the text in the supplied
+<structname>XIMText</structname>
+structure. For example, suppose the preedit buffer contains the string "ABCDE".
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+<literallayout class="monospaced">
+<!-- .ft C -->
+Text: A B C D E
+ ^ ^ ^ ^ ^ ^
+CharPos: 0 1 2 3 4 5
+<!-- .sp -->
+<!-- .ft P -->
+</literallayout>
+The CharPos in the diagram shows the location of the character position
+relative to the character.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If the value of chg_first is 1 and the value of chg_length is 3, this
+says to replace 3 characters beginning at character position 1 with the
+string in the
+<structname>XIMText</structname>
+structure.
+Hence, <acronym>BCD</acronym> would be replaced by the value in the structure.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Though chg_length and chg_first are both signed integers they will
+never have a negative value.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The caret member
+identifies the character position before which the cursor should
+be placed - after modification to the preedit buffer has been completed.
+For example, if caret is zero, the cursor is at
+the beginning of the buffer. If the caret is one, the cursor is between
+the first and second character.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XIMText</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 1.5i 3i -->
+typedef struct _XIMText {
+ unsigned short length;
+ XIMFeedback * feedback;
+ Bool encoding_is_wchar;
+ union {
+ char * multi_byte;
+ wchar_t * wide_char;
+ } string;
+} XIMText;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The text string passed is actually a structure specifying as follows:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+The length member is the text length in characters.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The encoding_is_wchar member is a value that indicates
+if the text string is encoded in wide character or multibyte format.
+The text string may be passed either as multibyte or as wide character;
+the input method controls in which form data is passed.
+The client's
+callback routine must be able to handle data passed in either form.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The string member is the text string.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+The feedback member indicates rendering type for each character in the
+string member.
+If string is NULL (indicating that only highlighting of the existing
+preedit buffer should be updated), feedback points to length highlight
+elements that should be applied to the existing preedit buffer, beginning
+at chg_first.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+The feedback member expresses the types of rendering feedback
+the callback should apply when drawing text.
+Rendering of the text to be drawn is specified either in generic ways
+(for example, primary, secondary) or in specific ways (reverse, underline).
+When generic indications are given,
+the client is free to choose the rendering style.
+It is necessary, however, that primary and secondary be mapped
+to two distinct rendering styles.
+</para>
+<para>
+<!-- .LP -->
+If an input method wants to control display of the preedit string, an
+input method can indicate the visibility hints using feedbacks in
+a specific way.
+The
+<symbol>XIMVisibleToForward</symbol>,
+<symbol>XIMVisibleToBackword</symbol>,
+and
+<symbol>XIMVisibleToCenter</symbol>
+masks are exclusively used for these visibility hints.
+The
+<symbol>XIMVisibleToForward</symbol>
+mask
+indicates that the preedit text is preferably displayed in the
+primary draw direction from the
+caret position in the preedit area forward.
+The
+<symbol>XIMVisibleToBackword</symbol>
+mask
+indicates that the preedit text is preferably displayed from
+the caret position in the preedit area backward, relative to the primary
+draw direction.
+The
+<symbol>XIMVisibleToCenter</symbol>
+mask
+indicates that the preedit text is preferably displayed with
+the caret position in the preedit area centered.
+</para>
+<para>
+<!-- .LP -->
+The insertion point of the preedit string could exist outside of
+the visible area when visibility hints are used.
+Only one of the
+masks
+is valid for the entire preedit string, and only one character
+can hold one of these feedbacks for a given input context at one time.
+This feedback may be OR'ed together with another highlight (such as
+<symbol>XIMReverse</symbol>).
+Only the most recently set feedback is valid, and any previous
+feedback is automatically canceled. This is a hint to the client, and
+the client is free to choose how to display the preedit string.
+</para>
+<para>
+<!-- .LP -->
+The feedback member also specifies how rendering of the text argument
+should be performed.
+If the feedback is NULL,
+the callback should apply the same feedback as is used for the surrounding
+characters in the preedit buffer; if chg_first is at a highlight boundary,
+the client can choose which of the two highlights to use.
+If feedback is not NULL, feedback specifies an array defining the
+rendering for each
+character of the string, and the length of the array is thus length.
+</para>
+<para>
+<!-- .LP -->
+If an input method wants to indicate that it is only updating the feedback of
+the preedit text without changing the content of it,
+the
+<structname>XIMText</structname>
+structure will contain a NULL value for the string field,
+the number of characters affected (relative to chg_first)
+will be in the length field,
+and the feedback field will point to an array of
+<type>XIMFeedback</type>.
+</para>
+<para>
+<!-- .LP -->
+Each element in the feedback array is a bitmask represented by a value of type
+<type>XIMFeedback</type>.
+The valid mask names are as follows:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XIMReverse</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMUnderline</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMHighlight</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPrimary</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMSecondary</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMTertiary</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMVisibleToForward</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMVisibleToBackward</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMVisibleToCenter</primary></indexterm>
+<!-- .sM -->
+</para>
+<literallayout class="monospaced">
+typedef unsigned long XIMFeedback;
+
+#define XIMReverse 1L
+#define XIMUnderline (1L&lt;&lt;1)
+#define XIMHighlight (1L&lt;&lt;2)
+#define XIMPrimary (1L&lt;&lt;5)*
+#define XIMSecondary (1L&lt;&lt;6)*
+#define XIMTertiary (1L&lt;&lt;7)*
+#define XIMVisibleToForward (1L&lt;&lt;8)
+#define XIMVisibleToBackward (1L&lt;&lt;9)
+#define XIMVisibleToCenter (1L&lt;&lt;10)
+
+*† The values for XIMPrimary, XIMSecondary, and XIMTertiary were incorrectly defined in
+the R5 specification. The X Consortium’s X11R5 implementation correctly
+implemented the values for these highlights. The value of these highlights has
+been corrected in this specification to agree with the values in the
+Consortium’s X11R5 and X11R6 implementations.
+
+</literallayout>
+
+<para>
+<!-- .LP -->
+Characters drawn with the
+<symbol>XIMReverse</symbol>
+highlight should be drawn by swapping the foreground and background colors
+used to draw normal, unhighlighted characters.
+Characters drawn with the
+<symbol>XIMUnderline</symbol>
+highlight should be underlined.
+Characters drawn with the
+<symbol>XIMHighlight</symbol>,
+<symbol>XIMPrimary</symbol>,
+<symbol>XIMSecondary</symbol>,
+and
+<symbol>XIMTertiary</symbol>
+highlights should be drawn in some unique manner that must be different
+from
+<symbol>XIMReverse</symbol>
+and
+<symbol>XIMUnderline</symbol>.
+<!-- .FS \(dg -->
+The values for
+<symbol>XIMPrimary</symbol>,
+<symbol>XIMSecondary</symbol>,
+and
+<symbol>XIMTertiary</symbol>
+were incorrectly defined in the R5 specification.
+The X Consortium's X11R5
+implementation correctly implemented the values for these highlights.
+The value of these highlights has been corrected in this specification
+to agree with the values in the Consortium's X11R5 and X11R6 implementations.
+<!-- .FE -->
+</para>
+</sect3>
+<sect3 id="Preedit_Caret_Callback">
+<title>Preedit Caret Callback</title>
+<!-- .XS -->
+<!-- (SN Preedit Caret Callback -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+An input method may have its own navigation keys to allow the user
+to move the text insertion point in the preedit area
+(for example, to move backward or forward).
+Consequently, input method needs to indicate to the client that it
+should move the text insertion point.
+It then calls the PreeditCaretCallback.
+<indexterm significance="preferred"><primary>PreeditCaretCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='preeditcaretcallback'>
+<funcprototype>
+ <funcdef>void <function><replaceable>PreeditCaretCallback</replaceable></function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XIMPreeditCaretCallbackStruct<parameter> *call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the preedit caret information.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The input method will trigger PreeditCaretCallback
+to move the text insertion point during preedit.
+The call_data argument contains a pointer to an
+<structname>XIMPreeditCaretCallbackStruct</structname>
+structure,
+which indicates where the caret should be moved.
+The callback must move the insertion point to its new location
+and return, in field position, the new offset value from the initial position.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XIMPreeditCaretCallbackStruct</structname>
+structure is defined as follows:
+<indexterm significance="preferred"><primary>XIMPreeditCaretCallbackStruct</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct _XIMPreeditCaretCallbackStruct {
+ int position; /* Caret offset within preedit string */
+ XIMCaretDirection direction; /* Caret moves direction */
+ XIMCaretStyle style; /* Feedback of the caret */
+} XIMPreeditCaretCallbackStruct;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<structname>XIMCaretStyle</structname>
+structure is defined as follows:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XIMCaretStyle</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef enum {
+ XIMIsInvisible, /* Disable caret feedback */
+ XIMIsPrimary, /* <acronym>UI</acronym> defined caret feedback */
+ XIMIsSecondary, /* <acronym>UI</acronym> defined caret feedback */
+} XIMCaretStyle;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<structname>XIMCaretDirection</structname>
+structure is defined as follows:
+<indexterm significance="preferred"><primary>XIMCaretDirection</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef enum {
+ XIMForwardChar, XIMBackwardChar,
+ XIMForwardWord, XIMBackwardWord,
+ XIMCaretUp, XIMCaretDown,
+ XIMNextLine, XIMPreviousLine,
+ XIMLineStart, XIMLineEnd,
+ XIMAbsolutePosition,
+ XIMDontChange,
+ } XIMCaretDirection;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+These values are defined as follows:
+</para>
+<indexterm significance="preferred"><primary>XIMForwardChar</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMBackwardChar</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMForwardWord</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMBackwardWord</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMCaretUp</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMCaretDown</primary></indexterm>
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <tbody>
+ <row>
+ <entry><constant>XIMForwardChar</constant></entry>
+ <entry>Move the caret forward one character position.</entry>
+ </row>
+ <row>
+ <entry><constant>XIMBackwardChar</constant></entry>
+ <entry>Move the caret backward one character position.</entry>
+ </row>
+ <row>
+ <entry><constant>XIMForwardWord</constant></entry>
+ <entry>Move the caret forward one word.</entry>
+ </row>
+ <row>
+ <entry><constant>XIMBackwardWord</constant></entry>
+ <entry>Move the caret backward one word.</entry>
+ </row>
+ <row>
+ <entry><constant>XIMCaretUp</constant></entry>
+ <entry>Move the caret up one line keeping the current horizontal offset.</entry>
+ </row>
+ <row>
+ <entry><constant>XIMCaretDown</constant></entry>
+ <entry>Move the caret down one line keeping the current horizontal offset.</entry>
+ </row>
+ <row>
+ <entry><constant>XIMPreviousLine</constant></entry>
+ <entry>Move the caret to the beginning of the previous line.</entry>
+ </row>
+ <row>
+ <entry><constant>XIMNextLine</constant></entry>
+ <entry>Move the caret to the beginning of the next line.</entry>
+ </row>
+ <row>
+ <entry><constant>XIMLineStart</constant></entry>
+ <entry>Move the caret to the beginning of the current display line that contains the caret.</entry>
+ </row>
+ <row>
+ <entry><constant>XIMLineEnd</constant></entry>
+ <entry>Move the caret to the end of the current display line that contains the caret.</entry>
+ </row>
+ <row>
+ <entry><constant>XIMAbsolutePosition</constant></entry>
+ <entry>The callback must move to the location specified by the position field
+ of the callback data, indicated in characters, starting from the beginning
+ of the preedit text.
+ Hence, a value of zero means move back to the beginning of the preedit text.</entry>
+ </row>
+ <row>
+ <entry><constant>XIMDontChange</constant></entry>
+ <entry>The caret position does not change.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<indexterm significance="preferred"><primary>XIMNextLine</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMPreviousLine</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMLineStart</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMLineEnd</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMAbsolutePosition</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMDontChange</primary></indexterm>
+</sect3>
+<sect3 id="Status_Callbacks">
+<title>Status Callbacks</title>
+<!-- .XS -->
+<!-- (SN Status Callbacks -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+An input method may communicate changes in the status of an input context
+(for example, created, destroyed, or focus changes) with three status
+callbacks: StatusStartCallback, StatusDoneCallback, and StatusDrawCallback.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+When the input context is created or gains focus,
+the input method calls the StatusStartCallback callback.
+<indexterm significance="preferred"><primary>StatusStartCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='statusstartcallback'>
+<funcprototype>
+ <funcdef>void <function><replaceable>StatusStartCallback</replaceable></function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XPointer<parameter> call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Not used for this callback and always passed as NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The callback should initialize appropriate data for displaying status
+and for responding to StatusDrawCallback calls.
+Once StatusStartCallback is called,
+it will not be called again before StatusDoneCallback has been called.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+When an input context
+is destroyed or when it loses focus, the input method calls StatusDoneCallback.
+<indexterm significance="preferred"><primary>StatusDoneCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='statusdonecallback'>
+<funcprototype>
+ <funcdef>void <function><replaceable>StatusDoneCallback</replaceable></function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XPointer<parameter> call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Not used for this callback and always passed as NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The callback may release any data allocated on
+<function>StatusStart</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+When an input context status has to be updated, the input method calls
+StatusDrawCallback.
+<indexterm significance="preferred"><primary>StatusDrawCallback</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='statusdrawcallback'>
+<funcprototype>
+ <funcdef>void <function><replaceable>StatusDrawCallback</replaceable></function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XPointer<parameter> client_data</parameter></paramdef>
+ <paramdef>XIMStatusDrawCallbackStruct<parameter> *call_data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>client_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the additional client data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>call_data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the status drawing information.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The callback should update the status area by either drawing a string
+or imaging a bitmap in the status area.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XIMStatusDataType</structname>
+and
+<structname>XIMStatusDrawCallbackStruct</structname>
+structures are defined as follows:
+<indexterm significance="preferred"><primary>XIMStatusDataType</primary></indexterm>
+<indexterm significance="preferred"><primary>XIMStatusDrawCallbackStruct</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 1i 3i -->
+<!-- .ta .5i 1i 3i -->
+typedef enum {
+ XIMTextType,
+ XIMBitmapType,
+} XIMStatusDataType;
+
+typedef struct _XIMStatusDrawCallbackStruct {
+ XIMStatusDataType type;
+ union {
+ XIMText *text;
+ Pixmap bitmap;
+ } data;
+} XIMStatusDrawCallbackStruct;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+</para>
+<para>
+<!-- .LP -->
+The feedback styles
+<symbol>XIMVisibleToForward</symbol>,
+<symbol>XIMVisibleToBackword</symbol>,
+and
+<symbol>XIMVisibleToCenter</symbol>
+are not relevant and will not appear in the
+<type>XIMFeedback</type>
+element of the
+<structname>XIMText</structname>
+structure.
+</para>
+<para>
+<!-- .LP -->
+</para>
+</sect3>
+</sect2>
+<sect2 id="Event_Filtering_b">
+<title>Event Filtering</title>
+<!-- .XS -->
+<!-- (SN Event Filtering -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides the ability for an input method
+to register a filter internal to Xlib.
+This filter is called by a client (or toolkit) by calling
+<function>XFilterEvent</function>
+after calling
+<function>XNextEvent</function>.
+Any client that uses the
+<type>XIM</type>
+interface should call
+<function>XFilterEvent</function>
+to allow input methods to process their events without knowledge
+of the client's dispatching mechanism.
+A client's user interface policy may determine the priority
+of event filters with respect to other event-handling mechanisms
+(for example, modal grabs).
+</para>
+<para>
+<!-- .LP -->
+Clients may not know how many filters there are, if any,
+and what they do.
+They may only know if an event has been filtered on return of
+<function>XFilterEvent</function>.
+Clients should discard filtered events.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To filter an event, use
+<function>XFilterEvent</function>.
+<indexterm significance="preferred"><primary>XFilterEvent</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfilterevent'>
+<funcprototype>
+ <funcdef>Bool <function>XFilterEvent</function></funcdef>
+ <paramdef>XEvent<parameter> *event</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<!-- .ds Ev event to filter -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the (Ev.
+<!-- .ds Wi for which the filter is to be applied -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window (Wi.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If the window argument is
+<symbol>None</symbol>,
+<function>XFilterEvent</function>
+applies the filter to the window specified in the
+<structname>XEvent</structname>
+structure.
+The window argument is provided so that layers above Xlib
+that do event redirection can indicate to which window an event
+has been redirected.
+</para>
+<para>
+<!-- .LP -->
+If
+<function>XFilterEvent</function>
+returns
+<symbol>True</symbol>,
+then some input method has filtered the event,
+and the client should discard the event.
+If
+<function>XFilterEvent</function>
+returns
+<symbol>False</symbol>,
+then the client should continue processing the event.
+</para>
+<para>
+<!-- .LP -->
+If a grab has occurred in the client and
+<function>XFilterEvent</function>
+returns
+<symbol>True</symbol>,
+the client should ungrab the keyboard.
+</para>
+</sect2>
+<sect2 id="Getting_Keyboard_Input_b">
+<title>Getting Keyboard Input</title>
+<!-- .XS -->
+<!-- (SN Getting Keyboard Input -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To get composed input from an input method,
+use
+<function>XmbLookupString</function>
+or
+<function>XwcLookupString</function>.
+<indexterm significance="preferred"><primary>XmbLookupString</primary></indexterm>
+<indexterm significance="preferred"><primary>XwcLookupString</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmblookupstring'>
+<funcprototype>
+ <funcdef>int <function>XmbLookupString</function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XKeyPressedEvent<parameter> *event</parameter></paramdef>
+ <paramdef>char<parameter> *buffer_return</parameter></paramdef>
+ <paramdef>int<parameter> bytes_buffer</parameter></paramdef>
+ <paramdef>KeySym<parameter> *keysym_return</parameter></paramdef>
+ <paramdef>Status<parameter> *status_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<funcsynopsis id='xwclookupstring'>
+<funcprototype>
+ <funcdef>int <function>XwcLookupString</function></funcdef>
+ <paramdef>XIC<parameter> ic</parameter></paramdef>
+ <paramdef>XKeyPressedEvent<parameter> *event</parameter></paramdef>
+ <paramdef>wchar_t<parameter> *buffer_return</parameter></paramdef>
+ <paramdef>int<parameter> wchars_buffer</parameter></paramdef>
+ <paramdef>KeySym<parameter> *keysym_return</parameter></paramdef>
+ <paramdef>Status<parameter> *status_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ic</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the input context.
+<!-- .ds Ev key event to be used -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the (Ev.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>buffer_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns a multibyte string or wide character string (if any)
+from the input method.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bytes_buffer</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>wchars_buffer</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies space available in the return buffer.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the KeySym computed from the event if this argument is not NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>status_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns a value indicating what kind of data is returned.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XmbLookupString</function>
+and
+<function>XwcLookupString</function>
+functions return the string from the input method specified
+in the buffer_return argument.
+If no string is returned,
+the buffer_return argument is unchanged.
+</para>
+<para>
+<!-- .LP -->
+The KeySym into which the KeyCode from the event was mapped is returned
+in the keysym_return argument if it is non-NULL and the status_return
+argument indicates that a KeySym was returned.
+If both a string and a KeySym are returned,
+the KeySym value does not necessarily correspond to the string returned.
+</para>
+<para>
+<!-- .LP -->
+<function>XmbLookupString</function>
+returns the length of the string in bytes, and
+<function>XwcLookupString</function>
+returns the length of the string in characters.
+Both
+<function>XmbLookupString</function>
+and
+<function>XwcLookupString</function>
+return text in the encoding of the locale bound to the input method
+of the specified input context.
+</para>
+<para>
+<!-- .LP -->
+Each string returned by
+<function>XmbLookupString</function>
+and
+<function>XwcLookupString</function>
+begins in the initial state of the encoding of the locale
+(if the encoding of the locale is state-dependent).
+<!-- .NT -->
+<note><para>
+To insure proper input processing,
+it is essential that the client pass only
+<symbol>KeyPress</symbol>
+events to
+<function>XmbLookupString</function>
+and
+<function>XwcLookupString</function>.
+Their behavior when a client passes a
+<symbol>KeyRelease</symbol>
+event is undefined.
+</para></note>
+<!-- .NE -->
+</para>
+<para>
+<!-- .LP -->
+Clients should check the status_return argument before
+using the other returned values.
+These two functions both return a value to status_return
+that indicates what has been returned in the other arguments.
+The possible values returned are:
+</para>
+
+<informaltable>
+ <tgroup cols='2' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <tbody>
+ <row>
+ <entry><symbol>XBufferOverflow</symbol></entry>
+ <entry>The input string to be returned is too large for the supplied buffer_return.
+ The required size
+ (<function>XmbLookupString</function>
+ in bytes;
+ <function>XwcLookupString</function>
+ in characters) is returned as the value of the function,
+ and the contents of buffer_return and keysym_return are not modified.
+ The client should recall the function with the same event
+ and a buffer of adequate size to obtain the string.</entry>
+ </row>
+ <row>
+ <entry><symbol>XLookupNone</symbol></entry>
+ <entry>No consistent input has been composed so far.
+ The contents of buffer_return and keysym_return are not modified,
+ and the function returns zero.</entry>
+ </row>
+ <row>
+ <entry><symbol>XLookupChars</symbol></entry>
+ <entry>Some input characters have been composed.
+ They are placed in the buffer_return argument,
+ and the string length is returned as the value of the function.
+ The string is encoded in the locale bound to the input context.
+ The content of the keysym_return argument is not modified.</entry>
+ </row>
+ <row>
+ <entry><symbol>XLookupKeySym</symbol></entry>
+ <entry>A KeySym has been returned instead of a string
+ and is returned in keysym_return.
+ The content of the buffer_return argument is not modified,
+ and the function returns zero.</entry>
+ </row>
+ <row>
+ <entry><symbol>XLookupBoth</symbol></entry>
+ <entry>Both a KeySym and a string are returned;
+ <symbol>XLookupChars</symbol>
+ and
+ <symbol>XLookupKeySym</symbol>
+ occur simultaneously.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+<!-- .LP -->
+It does not make any difference if the input context passed as an argument to
+<function>XmbLookupString</function>
+and
+<function>XwcLookupString</function>
+is the one currently in possession of the focus or not.
+Input may have been composed within an input context before it lost the focus,
+and that input may be returned on subsequent calls to
+<function>XmbLookupString</function>
+or
+<function>XwcLookupString</function>
+even though it does not have any more keyboard focus.
+</para>
+</sect2>
+<sect2 id="Input_Method_Conventions">
+<title>Input Method Conventions</title>
+<!-- .XS -->
+<!-- (SN Input Method Conventions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The input method architecture is transparent to the client.
+However, clients should respect a number of conventions in order
+to work properly.
+Clients must also be aware of possible effects of synchronization
+between input method and library in the case of a remote input server.
+</para>
+<sect3 id="Client_Conventions">
+<title>Client Conventions</title>
+<!-- .XS -->
+<!-- (SN Client Conventions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+A well-behaved client (or toolkit) should first query the input method style.
+If the client cannot satisfy the requirements of the supported styles
+(in terms of geometry management or callbacks),
+it should negotiate with the user continuation of the program
+or raise an exception or error of some sort.
+</para>
+</sect3>
+<sect3 id="Synchronization_Conventions">
+<title>Synchronization Conventions</title>
+<!-- .XS -->
+<!-- (SN Synchronization Conventions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+A
+<symbol>KeyPress</symbol>
+event with a KeyCode of zero is used exclusively as a
+signal that an input method has composed input that can be returned by
+<function>XmbLookupString</function>
+or
+<function>XwcLookupString</function>.
+No other use is made of a
+<symbol>KeyPress</symbol>
+event with KeyCode of zero.
+</para>
+<para>
+<!-- .LP -->
+Such an event may be generated by either a front-end
+or a back-end input method in an implementation-dependent manner.
+Some possible ways to generate this event include:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+A synthetic event sent by an input method server
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+An artificial event created by a input method filter and pushed
+onto a client's event queue
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+A
+<symbol>KeyPress</symbol>
+event whose KeyCode value is modified by an input method filter
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+When callback support is specified by the client,
+input methods will not take action unless they explicitly
+called back the client and obtained no response
+(the callback is not specified or returned invalid data).
+</para>
+</sect3>
+</sect2>
+</sect1>
+<sect1 id="String_Constants">
+<title>String Constants</title>
+<!-- .XS -->
+<!-- (SN String Constants -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The following symbols for string constants are defined in
+&lt;X11/Xlib.h&gt; .
+Although they are shown here with particular macro definitions,
+they may be implemented as macros, as global symbols, or as a
+mixture of the two. The string pointer value itself
+is not significant; clients must not assume that inequality of two
+values implies inequality of the actual string data.
+</para>
+
+<literallayout class="monospaced">
+#define XNVaNestedList "XNVaNestedList"
+#define XNSeparatorofNestedList "separatorofNestedList"
+#define XNQueryInputStyle "queryInputStyle"
+#define XNClientWindow "clientWindow"
+#define XNInputStyle "inputStyle"
+#define XNFocusWindow "focusWindow"
+#define XNResourceName "resourceName"
+#define XNResourceClass "resourceClass"
+#define XNGeometryCallback "geometryCallback"
+#define XNDestroyCallback "destroyCallback"
+#define XNFilterEvents "filterEvents"
+#define XNPreeditStartCallback "preeditStartCallback"
+#define XNPreeditDoneCallback "preeditDoneCallback"
+#define XNPreeditDrawCallback "preeditDrawCallback"
+#define XNPreeditCaretCallback "preeditCaretCallback"
+#define XNPreeditStateNotifyCallback "preeditStateNotifyCallback"
+#define XNPreeditAttributes "preeditAttributes"
+#define XNStatusStartCallback "statusStartCallback"
+#define XNStatusDoneCallback "statusDoneCallback"
+#define XNStatusDrawCallback "statusDrawCallback"
+#define XNStatusAttributes "statusAttributes"
+#define XNArea "area"
+#define XNAreaNeeded "areaNeeded"
+#define XNSpotLocation "spotLocation"
+#define XNColormap "colorMap"
+#define XNStdColormap "stdColorMap"
+#define XNForeground "foreground"
+#define XNBackground "background"
+#define XNBackgroundPixmap "backgroundPixmap"
+#define XNFontSet "fontSet"
+#define XNLineSpace "lineSpace"
+#define XNCursor "cursor"
+#define XNQueryIMValuesList "queryIMValuesList"
+#define XNQueryICValuesList "queryICValuesList"
+#define XNStringConversionCallback "stringConversionCallback"
+#define XNStringConversion "stringConversion"
+#define XNResetState "resetState"
+#define XNHotKey "hotkey"
+#define XNHotKeyState "hotkeyState"
+#define XNPreeditState "preeditState"
+#define XNVisiblePosition "visiblePosition"
+#define XNR6PreeditCallbackBehavior "r6PreeditCallback"
+#define XNRequiredCharSet "requiredCharSet"
+#define XNQueryOrientation "queryOrientation"
+#define XNDirectionalDependentDrawing "directionalDependentDrawing"
+#define XNContextualDrawing "contextualDrawing"
+#define XNBaseFontName "baseFontName"
+#define XNMissingCharSet "missingCharSet"
+#define XNDefaultString "defaultString"
+#define XNOrientation "orientation"
+#define XNFontInfo "fontInfo"
+#define XNOMAutomatic "omAutomatic"
+
+</literallayout>
+
+</sect1>
+</chapter>
diff --git a/libX11/specs/libX11/CH14.xml b/libX11/specs/libX11/CH14.xml
index 2baf6d5bf..d0eb36f10 100644
--- a/libX11/specs/libX11/CH14.xml
+++ b/libX11/specs/libX11/CH14.xml
@@ -1,5206 +1,5206 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<chapter id="inter_client_communication_functions">
-<title>Inter-Client Communication Functions</title>
-<para>
-The Inter-Client Communication Conventions Manual, hereafter referred to as the <acronym>ICCCM</acronym>,
-details the X Consortium approved conventions that govern inter-client communications. These
-conventions ensure peer-to-peer client cooperation in the use of selections, cut buffers, and shared
-resources as well as client cooperation with window and session managers. For further information,
-see the Inter-Client Communication Conventions Manual.
-</para>
-<para>
-Xlib provides a number of standard properties and programming interfaces that are <acronym>ICCCM</acronym>
-compliant. The predefined atoms for some of these properties are defined in the &lt;X11/Xatom.h&gt;
-header file, where to avoid name conflicts with user symbols their #define name has an XA_ prefix.
-For further information about atoms and properties, see section 4.3.
-</para>
-<para>
-Xlib’s selection and cut buffer mechanisms provide the primary programming interfaces by which
-peer client applications communicate with each other (see sections 4.5 and 16.6). The functions
-discussed in this chapter provide the primary programming interfaces by which client applications
-communicate with their window and session managers as well as share standard colormaps.
-</para>
-<para>
-The standard properties that are of special interest for communicating with window and session
-managers are:
-</para>
-
-<informaltable>
- <tgroup cols='4' align='center'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <colspec colname='c4'/>
- <thead>
- <row>
- <entry>Name</entry>
- <entry>Type</entry>
- <entry>Format</entry>
- <entry>Description</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry><property>WM_CLASS</property></entry>
- <entry>STRING</entry>
- <entry>8</entry>
- <entry>Set by application programs to allow
- window and session managers to
- obtain the application’s resources
- from the resource database.
- </entry>
- </row>
- <row>
- <entry><property>WM_CLIENT_MACHINE</property></entry>
- <entry>TEXT</entry>
- <entry></entry>
- <entry>The string name of the machine on
- which the client application is running.
- </entry>
- </row>
- <row>
- <entry><property>WM_COLORMAP_WINDOWS</property></entry>
- <entry>WINDOWS</entry>
- <entry>32</entry>
- <entry>The list of window IDs that may
- need a different colormap from that
- of their top-level window.
- </entry>
- </row>
- <row>
- <entry><property>WM_COMMAND</property></entry>
- <entry>TEXT</entry>
- <entry></entry>
- <entry>The command and arguments, null
- separated, used to invoke the application.
- </entry>
- </row>
- <row>
- <entry><property>WM_HINTS</property></entry>
- <entry><property>WM_HINTS</property></entry>
- <entry>32</entry>
- <entry>Additional hints set by the client for
- use by the window manager. The C
- type of this property is XWMHints.
- </entry>
- </row>
- <row>
- <entry><property>WM_ICON_NAME</property></entry>
- <entry>TEXT</entry>
- <entry></entry>
- <entry>The name to be used in an icon.</entry>
- </row>
- <row>
- <entry><property>WM_ICON_SIZE</property></entry>
- <entry><property>WM_ICON_SIZE</property></entry>
- <entry>32</entry>
- <entry>The window manager may set this
- property on the root window to
- specify the icon sizes it supports.
- The C type of this property is
- XIconSize.
- </entry>
- </row>
- <row>
- <entry><property>WM_NAME</property></entry>
- <entry>TEXT</entry>
- <entry></entry>
- <entry>The name of the application.</entry>
- </row>
- <row>
- <entry><property>WM_NORMAL_HINTS</property></entry>
- <entry><property>WM_NORMAL_HINTS</property></entry>
- <entry>32</entry>
- <entry>Size hints for a window in its
- normal state. The C type of this
- property is XSizeHints.
- </entry>
- </row>
- <row>
- <entry><property>WM_PROTOCOLS</property></entry>
- <entry>ATOM</entry>
- <entry>32</entry>
- <entry>List of atoms that identify the
- communications protocols between the
- client and window manager in
- which the client is willing to participate.
- </entry>
- </row>
- <row>
- <entry><property>WM_STATE</property></entry>
- <entry><property>WM_STATE</property></entry>
- <entry>32</entry>
- <entry>Intended for communication
- between window and session managers only.
- </entry>
- </row>
- <row>
- <entry><property>WM_TRANSIENT_FOR</property></entry>
- <entry>WINDOW</entry>
- <entry>32</entry>
- <entry>Set by application programs to
- indicate to the window manager that a
- transient top-level window, such as a
- dialog box.
- </entry>
- </row>
- </tbody>
- </tgroup>
-</informaltable>
-
-<para>
-The remainder of this chapter discusses:
-</para>
-
-<itemizedlist>
- <listitem><para>Client to window manager communication</para></listitem>
- <listitem><para>Client to session manager communication</para></listitem>
- <listitem><para>Standard colormaps</para></listitem>
-</itemizedlist>
-
-<sect1 id="Client_to_Window_Manager_Communication">
-<title>Client to Window Manager Communication</title>
-<!-- .XS -->
-<!-- (SN Client to Window Manager Communication -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This section discusses how to:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Manipulate top-level windows
- </para>
- </listitem>
- <listitem>
- <para>
-Convert string lists
- </para>
- </listitem>
- <listitem>
- <para>
-Set and read text properties
- </para>
- </listitem>
- <listitem>
- <para>
-Set and read the <property>WM_NAME</property> property
- </para>
- </listitem>
- <listitem>
- <para>
-Set and read the <property>WM_ICON_NAME</property> property
- </para>
- </listitem>
- <listitem>
- <para>
-Set and read the <property>WM_HINTS</property> property
- </para>
- </listitem>
- <listitem>
- <para>
-Set and read the <property>WM_NORMAL_HINTS</property> property
- </para>
- </listitem>
- <listitem>
- <para>
-Set and read the <property>WM_CLASS</property> property
- </para>
- </listitem>
- <listitem>
- <para>
-Set and read the <property>WM_TRANSIENT_FOR</property> property
- </para>
- </listitem>
- <listitem>
- <para>
-Set and read the <property>WM_PROTOCOLS</property> property
- </para>
- </listitem>
- <listitem>
- <para>
-Set and read the <property>WM_COLORMAP_WINDOWS</property> property
- </para>
- </listitem>
- <listitem>
- <para>
-Set and read the <property>WM_ICON_SIZE</property> property
- </para>
- </listitem>
- <listitem>
- <para>
-Use window manager convenience functions
- </para>
- </listitem>
-</itemizedlist>
-<sect2 id="Manipulating_Top_Level_Windows">
-<title>Manipulating Top-Level Windows</title>
-<!-- .XS -->
-<!-- (SN Manipulating Top-Level Windows -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to change the visibility or size
-of top-level windows (that is, those that were created as children
-of the root window).
-Note that the subwindows that you create are ignored by window managers.
-Therefore,
-you should use the basic window functions described in chapter 3
-to manipulate your application's subwindows.
-</para>
-<para>
-<!-- .LP -->
-To request that a top-level window be iconified, use
-<function>XIconifyWindow</function>.
-<indexterm significance="preferred"><primary>XIconifyWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XIconifyWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>int<parameter> screen_number</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen_number</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the appropriate screen number on the host server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XIconifyWindow</function>
-function sends a <property>WM_CHANGE_STATE</property>
-<symbol>ClientMessage</symbol>
-event with a format of 32 and a first data element of
-<symbol>IconicState</symbol>
-(as described in section 4.1.4 of the
-<emphasis remap='I'>Inter-Client Communication Conventions Manual</emphasis>)
-and a window of w
-to the root window of the specified screen
-with an event mask set to
-<symbol>SubstructureNotifyMask</symbol> |
-<symbol>SubstructureRedirectMask</symbol>.
-Window managers may elect to receive this message and
-if the window is in its normal state,
-may treat it as a request to change the window's state from normal to iconic.
-If the <property>WM_CHANGE_STATE</property> property cannot be interned,
-<function>XIconifyWindow</function>
-does not send a message and returns a zero status.
-It returns a nonzero status if the client message is sent successfully;
-otherwise, it returns a zero status.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To request that a top-level window be withdrawn, use
-<function>XWithdrawWindow</function>.
-<indexterm significance="preferred"><primary>XWithdrawWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XWithdrawWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>int<parameter> screen_number</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen_number</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the appropriate screen number on the host server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XWithdrawWindow</function>
-function unmaps the specified window
-and sends a synthetic
-<symbol>UnmapNotify</symbol>
-event to the root window of the specified screen.
-Window managers may elect to receive this message
-and may treat it as a request to change the window's state to withdrawn.
-When a window is in the withdrawn state,
-neither its normal nor its iconic representations is visible.
-It returns a nonzero status if the
-<symbol>UnmapNotify</symbol>
-event is successfully sent;
-otherwise, it returns a zero status.
-</para>
-<para>
-<!-- .LP -->
-<function>XWithdrawWindow</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To request that a top-level window be reconfigured, use
-<function>XReconfigureWMWindow</function>.
-<indexterm significance="preferred"><primary>XReconfigureWMWindow</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XReconfigureWMWindow</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>int<parameter> screen_number</parameter></paramdef>
- <paramdef>unsignedint<parameter> value_mask</parameter></paramdef>
- <paramdef>XWindowChanges<parameter> *values</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen_number</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the appropriate screen number on the host server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies which values are to be set using information in
-the values structure.
-This mask is the bitwise inclusive OR of the valid configure window values bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>values</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XWindowChanges</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XReconfigureWMWindow</function>
-function issues a
-<systemitem>ConfigureWindow</systemitem>
-request on the specified top-level window.
-If the stacking mode is changed and the request fails with a
-<errorname>BadMatch</errorname>
-error,
-the error is trapped by Xlib and a synthetic
-<systemitem class="event">ConfigureRequestEvent</systemitem>
-containing the same configuration parameters is sent to the root
-of the specified window.
-Window managers may elect to receive this event
-and treat it as a request to reconfigure the indicated window.
-It returns a nonzero status if the request or event is successfully sent;
-otherwise, it returns a zero status.
-</para>
-<para>
-<!-- .LP -->
-<function>XReconfigureWMWindow</function>
-can generate
-<errorname>BadValue</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Converting_String_Lists">
-<title>Converting String Lists</title>
-<!-- .XS -->
-<!-- (SN Converting String Lists -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Many of the text properties allow a variety of types and formats.
-Because the data stored in these properties are not
-simple null-terminated strings, an
-<structname>XTextProperty</structname>
-structure is used to describe the encoding, type, and length of the text
-as well as its value.
-The
-<structname>XTextProperty</structname>
-structure contains:
-<indexterm significance="preferred"><primary>XTextProperty</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- unsigned char *value; /* property data */
- Atom encoding; /* type of property */
- int format; /* 8, 16, or 32 */
- unsigned long nitems; /* number of items in value */
-} XTextProperty;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Xlib provides functions to convert localized text to or from encodings
-that support the inter-client communication conventions for text.
-In addition, functions are provided for converting between lists of pointers
-to character strings and text properties in the STRING encoding.
-</para>
-<para>
-<!-- .LP -->
-The functions for localized text return a signed integer error status
-that encodes
-<symbol>Success</symbol>
-as zero, specific error conditions as negative numbers, and partial conversion
-as a count of unconvertible characters.
-</para>
-
-<literallayout class="monospaced">
-
-#define #XNoMemory -1
-#define #XLocaleNotSupported -2
-#define #XConverterNotFound -3
-
-typedef enum {
- XStringStyle, /* STRING */
- XCompoundTextStyle, /* COMPOUND_TEXT */
- XTextStyle, /* text in owner's encoding (current locale) */
- XStdICCTextStyle /* STRING, else COMPOUND_TEXT */
-} XICCEncodingStyle;
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To convert a list of text strings to an
-<structname>XTextProperty</structname>
-structure, use
-<function>XmbTextListToTextProperty</function>
-or
-<function>XwcTextListToTextProperty</function>.
-<indexterm significance="preferred"><primary>XmbTextListToTextProperty</primary></indexterm>
-<indexterm significance="preferred"><primary>XwcTextListToTextProperty</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XmbTextListToTextProperty</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> **list</parameter></paramdef>
- <paramdef>int<parameter> count</parameter></paramdef>
- <paramdef>XICCEncodingStyle<parameter> style</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XwcTextListToTextProperty</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>wchar_t<parameter> **list</parameter></paramdef>
- <paramdef>int<parameter> count</parameter></paramdef>
- <paramdef>XICCEncodingStyle<parameter> style</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a list of null-terminated character strings.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of strings specified.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>style</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the manner in which the property is encoded.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>text_prop_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the
-<structname>XTextProperty</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XmbTextListToTextProperty</function>
-and
-<function>XwcTextListToTextProperty</function>
-functions set the specified
-<structname>XTextProperty</structname>
-value to a set of null-separated elements representing the concatenation
-of the specified list of null-terminated text strings.
-A final terminating null is stored at the end of the value field
-of text_prop_return but is not included in the nitems member.
-</para>
-<para>
-<!-- .LP -->
-The functions set the encoding field of text_prop_return to an
-<type>Atom</type>
-for the specified display
-naming the encoding determined by the specified style
-and convert the specified text list to this encoding for storage in
-the text_prop_return value field.
-If the style
-<constant>XStringStyle</constant>
-or
-<constant>XCompoundTextStyle</constant>
-is specified,
-this encoding is ``STRING'' or ``COMPOUND_TEXT'', respectively.
-If the style
-<constant>XTextStyle</constant>
-is specified,
-this encoding is the encoding of the current locale.
-If the style
-<constant>XStdICCTextStyle</constant>
-is specified,
-this encoding is ``STRING'' if the text is fully convertible to STRING,
-else ``COMPOUND_TEXT''.
-</para>
-<para>
-<!-- .LP -->
-If insufficient memory is available for the new value string,
-the functions return
-<symbol>XNoMemory</symbol>.
-If the current locale is not supported,
-the functions return
-<symbol>XLocaleNotSupported</symbol>.
-In both of these error cases,
-the functions do not set text_prop_return.
-</para>
-<para>
-<!-- .LP -->
-To determine if the functions are guaranteed not to return
-<symbol>XLocaleNotSupported</symbol>,
-use
-<function>XSupportsLocale</function>.
-</para>
-<para>
-<!-- .LP -->
-If the supplied text is not fully convertible to the specified encoding,
-the functions return the number of unconvertible characters.
-Each unconvertible character is converted to an implementation-defined and
-encoding-specific default string.
-Otherwise, the functions return
-<symbol>Success</symbol>.
-Note that full convertibility to all styles except
-<constant>XStringStyle</constant>
-is guaranteed.
-</para>
-<para>
-<!-- .LP -->
-To free the storage for the value field, use
-<function>XFree</function>.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain a list of text strings from an
-<structname>XTextProperty</structname>
-structure, use
-<function>XmbTextPropertyToTextList</function>
-or
-<function>XwcTextPropertyToTextList</function>.
-<indexterm significance="preferred"><primary>XmbTextPropertyToTextList</primary></indexterm>
-<indexterm significance="preferred"><primary>XwcTextPropertyToTextList</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XmbTextPropertyToTextList</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
- <paramdef>char<parameter> ***list_return</parameter></paramdef>
- <paramdef>int<parameter> *count_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XwcTextPropertyToTextList</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
- <paramdef>wchar_t<parameter> ***list_return</parameter></paramdef>
- <paramdef>int<parameter> *count_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>text_prop</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XTextProperty</structname>
-structure to be used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>list_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns a list of null-terminated character strings.
-<!-- .ds Cn strings -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of (Cn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XmbTextPropertyToTextList</function>
-and
-<function>XwcTextPropertyToTextList</function>
-functions return a list of text strings in the current locale representing the
-null-separated elements of the specified
-<structname>XTextProperty</structname>
-structure.
-The data in text_prop must be format 8.
-</para>
-<para>
-<!-- .LP -->
-Multiple elements of the property (for example, the strings in a disjoint
-text selection) are separated by a null byte.
-The contents of the property are not required to be null-terminated;
-any terminating null should not be included in text_prop.nitems.
-</para>
-<para>
-<!-- .LP -->
-If insufficient memory is available for the list and its elements,
-<function>XmbTextPropertyToTextList</function>
-and
-<function>XwcTextPropertyToTextList</function>
-return
-<symbol>XNoMemory</symbol>.
-If the current locale is not supported,
-the functions return
-<symbol>XLocaleNotSupported</symbol>.
-Otherwise, if the encoding field of text_prop is not convertible
-to the encoding of the current locale,
-the functions return
-<symbol>XConverterNotFound</symbol>.
-For supported locales,
-existence of a converter from COMPOUND_TEXT, STRING
-or the encoding of the current locale is guaranteed if
-<function>XSupportsLocale</function>
-returns
-<symbol>True</symbol>
-for the current locale (but the actual text
-may contain unconvertible characters).
-Conversion of other encodings is implementation-dependent.
-In all of these error cases,
-the functions do not set any return values.
-</para>
-<para>
-<!-- .LP -->
-Otherwise,
-<function>XmbTextPropertyToTextList</function>
-and
-<function>XwcTextPropertyToTextList</function>
-return the list of null-terminated text strings to list_return
-and the number of text strings to count_return.
-</para>
-<para>
-<!-- .LP -->
-If the value field of text_prop is not fully convertible to the encoding of
-the current locale,
-the functions return the number of unconvertible characters.
-Each unconvertible character is converted to a string in the
-current locale that is specific to the current locale.
-To obtain the value of this string,
-use
-<function>XDefaultString</function>.
-Otherwise,
-<function>XmbTextPropertyToTextList</function>
-and
-<function>XwcTextPropertyToTextList</function>
-return
-<symbol>Success</symbol>.
-</para>
-<para>
-<!-- .LP -->
-To free the storage for the list and its contents returned by
-<function>XmbTextPropertyToTextList</function>,
-use
-<function>XFreeStringList</function>.
-To free the storage for the list and its contents returned by
-<function>XwcTextPropertyToTextList</function>,
-use
-<function>XwcFreeStringList</function>.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To free the in-memory data associated with the specified
-wide character string list, use
-<function>XwcFreeStringList</function>.
-<indexterm significance="preferred"><primary>XwcFreeStringList</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XwcFreeStringList</function></funcdef>
- <paramdef>wchar_t<parameter> **list</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the list of strings to be freed.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XwcFreeStringList</function>
-function frees memory allocated by
-<function>XwcTextPropertyToTextList</function>.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the default string for text conversion in the current locale,
-use</para>
-
-<para>char *XDefaultString()</para>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDefaultString</function>
-function returns the default string used by Xlib for text conversion
-(for example, in
-<function>XmbTextPropertyToTextList</function>).
-The default string is the string in the current locale that is output
-when an unconvertible character is found during text conversion.
-If the string returned by
-<function>XDefaultString</function>
-is the empty string (""),
-no character is output in the converted text.
-<function>XDefaultString</function>
-does not return NULL.
-</para>
-<para>
-<!-- .LP -->
-The string returned by
-<function>XDefaultString</function>
-is independent of the default string for text drawing;
-see
-<function>XCreateFontSet</function>
-to obtain the default string for an
-<type>XFontSet</type>.
-</para>
-<para>
-<!-- .LP -->
-The behavior when an invalid codepoint is supplied to any Xlib function is
-undefined.
-</para>
-<para>
-<!-- .LP -->
-The returned string is null-terminated.
-It is owned by Xlib and should not be modified or freed by the client.
-It may be freed after the current locale is changed.
-Until freed, it will not be modified by Xlib.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set the specified list of strings in the STRING encoding to a
-<structname>XTextProperty</structname>
-structure, use
-<function>XStringListToTextProperty</function>.
-<indexterm significance="preferred"><primary>XStringListToTextProperty</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XStringListToTextProperty</function></funcdef>
- <paramdef>char<parameter> **list</parameter></paramdef>
- <paramdef>int<parameter> count</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a list of null-terminated character strings.
-<!-- .ds Cn strings -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of (Cn.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>text_prop_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the
-<structname>XTextProperty</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XStringListToTextProperty</function>
-function sets the specified
-<structname>XTextProperty</structname>
-to be of type STRING (format 8) with a value representing the
-concatenation of the specified list of null-separated character strings.
-An extra null byte (which is not included in the nitems member)
-is stored at the end of the value field of text_prop_return.
-The strings are assumed (without verification) to be in the STRING encoding.
-If insufficient memory is available for the new value string,
-<function>XStringListToTextProperty</function>
-does not set any fields in the
-<structname>XTextProperty</structname>
-structure and returns a zero status.
-Otherwise, it returns a nonzero status.
-To free the storage for the value field, use
-<function>XFree</function>.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain a list of strings from a specified
-<structname>XTextProperty</structname>
-structure in the STRING encoding, use
-<function>XTextPropertyToStringList</function>.
-<indexterm significance="preferred"><primary>XTextPropertyToStringList</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XTextPropertyToStringList</function></funcdef>
- <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
- <paramdef>char<parameter> ***list_return</parameter></paramdef>
- <paramdef>int<parameter> *count_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>text_prop</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XTextProperty</structname>
-structure to be used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>list_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns a list of null-terminated character strings.
-<!-- .ds Cn strings -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of (Cn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XTextPropertyToStringList</function>
-function returns a list of strings representing the null-separated elements
-of the specified
-<structname>XTextProperty</structname>
-structure.
-The data in text_prop must be of type STRING and format 8.
-Multiple elements of the property
-(for example, the strings in a disjoint text selection)
-are separated by NULL (encoding 0).
-The contents of the property are not null-terminated.
-If insufficient memory is available for the list and its elements,
-<function>XTextPropertyToStringList</function>
-sets no return values and returns a zero status.
-Otherwise, it returns a nonzero status.
-To free the storage for the list and its contents, use
-<function>XFreeStringList</function>.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To free the in-memory data associated with the specified string list, use
-<function>XFreeStringList</function>.
-<indexterm significance="preferred"><primary>XFreeStringList</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XFreeStringList</function></funcdef>
- <paramdef>char<parameter> **list</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the list of strings to be freed.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFreeStringList</function>
-function releases memory allocated by
-<function>XmbTextPropertyToTextList</function>
-and
-<function>XTextPropertyToStringList</function>
-and the missing charset list allocated by
-<function>XCreateFontSet</function>.
-</para>
-</sect2>
-<sect2 id="Setting_and_Reading_Text_Properties">
-<title>Setting and Reading Text Properties</title>
-<!-- .XS -->
-<!-- (SN Setting and Reading Text Properties -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides two functions that you can use to set and read
-the text properties for a given window.
-You can use these functions to set and read those properties of type TEXT
-(<property>WM_NAME</property>, <property>WM_ICON_NAME</property>, <property>WM_COMMAND</property>, and <property>WM_CLIENT_MACHINE</property>).
-In addition,
-Xlib provides separate convenience functions that you can use to set each
-of these properties.
-For further information about these convenience functions,
-see sections 14.1.4, 14.1.5, 14.2.1, and 14.2.2, respectively.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set one of a window's text properties, use
-<function>XSetTextProperty</function>.
-<indexterm significance="preferred"><primary>XSetTextProperty</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XSetTextProperty</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
- <paramdef>Atom<parameter> property</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>text_prop</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XTextProperty</structname>
-structure to be used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>property</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the property name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetTextProperty</function>
-function replaces the existing specified property for the named window
-with the data, type, format, and number of items determined
-by the value field, the encoding field, the format field,
-and the nitems field, respectively, of the specified
-<structname>XTextProperty</structname>
-structure.
-If the property does not already exist,
-<function>XSetTextProperty</function>
-sets it for the specified window.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetTextProperty</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadAtom</errorname>,
-<errorname>BadValue</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To read one of a window's text properties, use
-<function>XGetTextProperty</function>.
-<indexterm significance="preferred"><primary>XGetTextProperty</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetTextProperty</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
- <paramdef>Atom<parameter> property</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>text_prop_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the
-<structname>XTextProperty</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>property</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the property name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetTextProperty</function>
-function reads the specified property from the window
-and stores the data in the returned
-<structname>XTextProperty</structname>
-structure.
-It stores the data in the value field,
-the type of the data in the encoding field,
-the format of the data in the format field,
-and the number of items of data in the nitems field.
-An extra byte containing null (which is not included in the nitems member)
-is stored at the end of the value field of text_prop_return.
-The particular interpretation of the property's encoding
-and data as text is left to the calling application.
-If the specified property does not exist on the window,
-<function>XGetTextProperty</function>
-sets the value field to NULL,
-the encoding field to
-<symbol>None</symbol>,
-the format field to zero,
-and the nitems field to zero.
-</para>
-<para>
-<!-- .LP -->
-If it was able to read and store the data in the
-<structname>XTextProperty</structname>
-structure,
-<function>XGetTextProperty</function>
-returns a nonzero status;
-otherwise, it returns a zero status.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetTextProperty</function>
-can generate
-<errorname>BadAtom</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Setting_and_Reading_the_WM_NAME_Property">
-<title>Setting and Reading the WM_NAME Property</title>
-<!-- .XS -->
-<!-- (SN Setting and Reading the WM_NAME Property -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides convenience functions that you can use to set and read
-the <property>WM_NAME</property> property for a given window.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set a window's <property>WM_NAME</property> property with the supplied convenience function, use
-<function>XSetWMName</function>.
-<indexterm significance="preferred"><primary>XSetWMName</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XSetWMName</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>text_prop</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XTextProperty</structname>
-structure to be used.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWMName</function>
-convenience function calls
-<function>XSetTextProperty</function>
-to set the <property>WM_NAME</property> property.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To read a window's <property>WM_NAME</property> property with the supplied convenience function, use
-<function>XGetWMName</function>.
-<indexterm significance="preferred"><primary>XGetWMName</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetWMName</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>text_prop_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the
-<structname>XTextProperty</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetWMName</function>
-convenience function calls
-<function>XGetTextProperty</function>
-to obtain the <property>WM_NAME</property> property.
-It returns a nonzero status on success;
-otherwise, it returns a zero status.
-</para>
-<para>
-<!-- .LP -->
-The following two functions have been superseded by
-<function>XSetWMName</function>
-and
-<function>XGetWMName</function>,
-respectively.
-You can use these additional convenience functions
-for window names that are encoded as STRING properties.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To assign a name to a window, use
-<function>XStoreName</function>.
-<indexterm><primary>Window</primary><secondary>name</secondary></indexterm>
-<indexterm significance="preferred"><primary>XStoreName</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XStoreName</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>char<parameter> *window_name</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>window_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window name,
-which should be a null-terminated string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XStoreName</function>
-function assigns the name passed to window_name to the specified window.
-A window manager can display the window name in some prominent
-place, such as the title bar, to allow users to identify windows easily.
-Some window managers may display a window's name in the window's icon,
-although they are encouraged to use the window's icon name
-if one is provided by the application.
-If the string is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-<function>XStoreName</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To get the name of a window, use
-<function>XFetchName</function>.
-<indexterm significance="preferred"><primary>XFetchName</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XFetchName</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>char<parameter> **window_name_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>window_name_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the window name, which is a null-terminated string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFetchName</function>
-function returns the name of the specified window.
-If it succeeds,
-it returns a nonzero status;
-otherwise, no name has been set for the window,
-and it returns zero.
-If the <property>WM_NAME</property> property has not been set for this window,
-<function>XFetchName</function>
-sets window_name_return to NULL.
-If the data returned by the server is in the Latin Portable Character Encoding,
-then the returned string is in the Host Portable Character Encoding.
-Otherwise, the result is implementation-dependent.
-When finished with it, a client must free
-the window name string using
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XFetchName</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect2>
-<sect2 id="Setting_and_Reading_the_WM_ICON_NAME_Property">
-<title>Setting and Reading the WM_ICON_NAME Property</title>
-<!-- .XS -->
-<!-- (SN Setting and Reading the WM_ICON_NAME Property -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides convenience functions that you can use to set and read
-the <property>WM_ICON_NAME</property> property for a given window.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set a window's <property>WM_ICON_NAME</property> property,
-use
-<function>XSetWMIconName</function>.
-<indexterm significance="preferred"><primary>XSetWMIconName</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XSetWMIconName</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>text_prop</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XTextProperty</structname>
-structure to be used.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWMIconName</function>
-convenience function calls
-<function>XSetTextProperty</function>
-to set the <property>WM_ICON_NAME</property> property.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To read a window's <property>WM_ICON_NAME</property> property,
-use
-<function>XGetWMIconName</function>.
-<indexterm significance="preferred"><primary>XGetWMIconName</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetWMIconName</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>text_prop_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the
-<structname>XTextProperty</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetWMIconName</function>
-convenience function calls
-<function>XGetTextProperty</function>
-to obtain the <property>WM_ICON_NAME</property> property.
-It returns a nonzero status on success;
-otherwise, it returns a zero status.
-</para>
-<para>
-<!-- .LP -->
-The next two functions have been superseded by
-<function>XSetWMIconName</function>
-and
-<function>XGetWMIconName</function>,
-respectively.
-You can use these additional convenience functions
-for window names that are encoded as STRING properties.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the name to be displayed in a window's icon, use
-<function>XSetIconName</function>.
-<indexterm><primary>Window</primary><secondary>icon name</secondary></indexterm>
-<indexterm significance="preferred"><primary>XSetIconName</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetIconName</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>char<parameter> *icon_name</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>icon_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the icon name,
-which should be a null-terminated string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If the string is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-<function>XSetIconName</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To get the name a window wants displayed in its icon, use
-<function>XGetIconName</function>.
-<indexterm significance="preferred"><primary>XGetIconName</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetIconName</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>char<parameter> **icon_name_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>icon_name_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the window's icon name,
-which is a null-terminated string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetIconName</function>
-function returns the name to be displayed in the specified window's icon.
-If it succeeds, it returns a nonzero status; otherwise,
-if no icon name has been set for the window,
-it returns zero.
-If you never assigned a name to the window,
-<function>XGetIconName</function>
-sets icon_name_return to NULL.
-If the data returned by the server is in the Latin Portable Character Encoding,
-then the returned string is in the Host Portable Character Encoding.
-Otherwise, the result is implementation-dependent.
-When finished with it, a client must free
-the icon name string using
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetIconName</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect2>
-<sect2 id="Setting_and_Reading_the_WM_HINTS_Property">
-<title>Setting and Reading the WM_HINTS Property</title>
-<!-- .XS -->
-<!-- (SN Setting and Reading the WM_HINTS Property -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set and read
-the <property>WM_HINTS</property> property for a given window.
-These functions use the flags and the
-<structname>XWMHints</structname>
-structure, as defined in the
-<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
-<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-header file.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To allocate an
-<structname>XWMHints</structname>
-structure, use
-<function>XAllocWMHints</function>.
-</para>
-
-<para>
- XWMHints *XAllocWMHints()
-</para>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAllocWMHints</function>
-function allocates and returns a pointer to an
-<structname>XWMHints</structname>
-structure.
-Note that all fields in the
-<structname>XWMHints</structname>
-structure are initially set to zero.
-If insufficient memory is available,
-<function>XAllocWMHints</function>
-returns NULL.
-To free the memory allocated to this structure,
-use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XWMHints</structname>
-structure contains:
-</para>
-
-<literallayout class="monospaced">
-/* Window manager hints mask bits */
-
-#define InputHint (1L&lt;&lt;0)
-#define StateHint (1L&lt;&lt;1)
-#define IconPixmapHint (1L&lt;&lt;2)
-#define IconWindowHint (1L&lt;&lt;3)
-#define IconPositionHint (1L&lt;&lt;4)
-#define IconMaskHint (1L&lt;&lt;5)
-#define WindowGroupHint (1L&lt;&lt;6)
-#define UrgencyHint (1L&lt;&lt;8)
-#define AllHints (InputHint|StateHint|IconPixmapHint|
- IconWIndowHint|IconPositionHint|
- IconMaskHint|WindowGroupHint)
-
-
-/* Values */
-
-typedef struct {
- long flags; /* marks which fields in this structure are defined */
- Bool input; /* does this application rely on the window manager to
- get keyboard input? */
- int initial_state; /* see below */
- Pixmap icon_pixmap; /* pixmap to be used as icon */
- Window icon_window; /* window to be used as icon */
- int icon_x, icon_y; /* initial position of icon */
- Pixmap icon_mask; /* pixmap to be used as mask for icon_pixmap */
- XID window_group; /* id of related window group */
- /* this structure may be extended in the future */
-} XWMHints;
-</literallayout>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The input member is used to communicate to the window manager the input focus
-model used by the application.
-Applications that expect input but never explicitly set focus to any
-of their subwindows (that is, use the push model of focus management),
-such as X Version 10 style applications that use real-estate
-driven focus, should set this member to
-<symbol>True</symbol>.
-Similarly, applications
-that set input focus to their subwindows only when it is given to their
-top-level window by a window manager should also set this member to
-<symbol>True</symbol>.
-Applications that manage their own input focus by explicitly setting
-focus to one of their subwindows whenever they want keyboard input
-(that is, use the pull model of focus management) should set this member to
-<symbol>False</symbol>.
-Applications that never expect any keyboard input also should set this member
-to
-<symbol>False</symbol>.
-</para>
-<para>
-<!-- .LP -->
-Pull model window managers should make it possible for push model
-applications to get input by setting input focus to the top-level windows of
-applications whose input member is
-<symbol>True</symbol>.
-Push model window managers should
-make sure that pull model applications do not break them
-by resetting input focus to
-<symbol>PointerRoot</symbol>
-when it is appropriate (for example, whenever an application whose
-input member is
-<symbol>False</symbol>
-sets input focus to one of its subwindows).
-</para>
-<para>
-<!-- .LP -->
-The definitions for the initial_state flag are:
-</para>
-
-<literallayout class="monospaced">
-#define WithdrawnState 0
-#define NormalState 1 /* most applications start this way */
-#define IconicState 2 /* application wants to start as an icon */
-
-</literallayout>
-<para>
-The icon_mask specifies which pixels of the icon_pixmap should be used as the
-icon.
-This allows for nonrectangular icons.
-Both icon_pixmap and icon_mask must be bitmaps.
-The icon_window lets an application provide a window for use as an icon
-for window managers that support such use.
-The window_group lets you specify that this window belongs to a group
-of other windows.
-For example, if a single application manipulates multiple
-top-level windows, this allows you to provide enough
-information that a window manager can iconify all of the windows
-rather than just the one window.
-</para>
-<para>
-<!-- .LP -->
-The
-<symbol>UrgencyHint</symbol>
-flag, if set in the flags field, indicates that the client deems the window
-contents to be urgent, requiring the timely response of the user. The
-window manager will make some effort to draw the user's attention to this
-window while this flag is set. The client must provide some means by which the
-user can cause the urgency flag to be cleared (either mitigating
-the condition that made the window urgent or merely shutting off the alarm)
-or the window to be withdrawn.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set a window's <property>WM_HINTS</property> property, use
-<function>XSetWMHints</function>.
-<indexterm significance="preferred"><primary>XSetWMHints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetWMHints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XWMHints<parameter> *wmhints</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>wmhints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XWMHints</structname>
-structure to be used.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWMHints</function>
-function sets the window manager hints that include icon information and location,
-the initial state of the window, and whether the application relies on the
-window manager to get keyboard input.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetWMHints</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To read a window's <property>WM_HINTS</property> property, use
-<function>XGetWMHints</function>.
-<indexterm significance="preferred"><primary>XGetWMHints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XWMHints *<function>XGetWMHints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetWMHints</function>
-function reads the window manager hints and
-returns NULL if no <property>WM_HINTS</property> property was set on the window
-or returns a pointer to an
-<structname>XWMHints</structname>
-structure if it succeeds.
-When finished with the data,
-free the space used for it by calling
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetWMHints</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect2>
-<sect2 id="Setting_and_Reading_the_WM_NORMAL_HINTS_Property">
-<title>Setting and Reading the WM_NORMAL_HINTS Property</title>
-<!-- .XS -->
-<!-- (SN Setting and Reading the WM_NORMAL_HINTS Property -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set or read
-the <property>WM_NORMAL_HINTS</property> property for a given window.
-The functions use the flags and the
-<structname>XSizeHints</structname>
-structure, as defined in the
-<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
-<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-header file.
-</para>
-<para>
-<!-- .LP -->
-The size of the
-<structname>XSizeHints</structname>
-structure may grow in future releases, as new components are
-added to support new <acronym>ICCCM</acronym> features.
-Passing statically allocated instances of this structure into
-Xlib may result in memory corruption when running against a
-future release of the library.
-As such, it is recommended that only dynamically allocated
-instances of the structure be used.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To allocate an
-<structname>XSizeHints</structname>
-structure, use
-<function>XAllocSizeHints</function>.
-</para>
-
-<para>
-XSizeHints *XAllocSizeHints()
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAllocSizeHints</function>
-function allocates and returns a pointer to an
-<structname>XSizeHints</structname>
-structure.
-Note that all fields in the
-<structname>XSizeHints</structname>
-structure are initially set to zero.
-If insufficient memory is available,
-<function>XAllocSizeHints</function>
-returns NULL.
-To free the memory allocated to this structure,
-use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XSizeHints</structname>
-structure contains:
-</para>
-
-
-<literallayout class="monospaced">
-/* Size hints mask bits */
-
-#define USPosition (1L&lt;&lt;0) /* user specified x,y */
-#define USSize (1L&lt;&lt;1) /* user specified width,height */
-#define PPosition (1L&lt;&lt;2) /* program specified posistion */
-#define PSize (1L&lt;&lt;3) /* program specified size */
-#define PMinSize (1L&lt;&lt;4) /* program specified minimum size */
-#define PMaxSize (1L&lt;&lt;5) /* program specified maximum size */
-#define PResizeInc (1L&lt;&lt;5) /* program specified resize increments */
-#define PAspect (1L&lt;&lt;6) /* program specified min and max aspect ratios */
-#define PBaseSize (1L&lt;&lt;8)
-#define PWinGravity (1L&lt;&lt;9)
-#define PAllHints (PPosition|Psize|
- PMinSize|PMaxSize|
- PResizeInc|PAspect)
-
-
-/* Values */
-
-typedef struct {
- long flags; /* marks which fields in this structure are defined */
- int x, y; /* Obsolete */
- int width, height; /* Obsolete */
- int min_width, min_height;
- int max_width, max_height;
- int width_inc, height_inc;
- struct {
- int x; /* numerator */
- int y; /* denominator */
- } min_aspect, max_aspect;
- int base_width, base_height;
- int win_gravity;
- /* this structure may be extended in the future */
-} XSizeHints;
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The x, y, width, and height members are now obsolete
-and are left solely for compatibility reasons.
-The min_width and min_height members specify the
-minimum window size that still allows the application to be useful.
-The max_width and max_height members specify the maximum window size.
-The width_inc and height_inc members define an arithmetic progression of
-sizes (minimum to maximum) into which the window prefers to be resized.
-The min_aspect and max_aspect members are expressed
-as ratios of x and y,
-and they allow an application to specify the range of aspect
-ratios it prefers.
-The base_width and base_height members define the desired size of the window.
-The window manager will interpret the position of the window
-and its border width to position the point of the outer rectangle
-of the overall window specified by the win_gravity member.
-The outer rectangle of the window includes any borders or decorations
-supplied by the window manager.
-In other words,
-if the window manager decides to place the window where the client asked,
-the position on the parent window's border named by the win_gravity
-will be placed where the client window would have been placed
-in the absence of a window manager.
-</para>
-<para>
-<!-- .LP -->
-Note that use of the
-<symbol>PAllHints</symbol>
-macro is highly discouraged.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set a window's <property>WM_NORMAL_HINTS</property> property, use
-<function>XSetWMNormalHints</function>.
-<indexterm significance="preferred"><primary>XSetWMNormalHints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XSetWMNormalHints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the size hints for the window in its normal state.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWMNormalHints</function>
-function replaces the size hints for the <property>WM_NORMAL_HINTS</property> property
-on the specified window.
-If the property does not already exist,
-<function>XSetWMNormalHints</function>
-sets the size hints for the <property>WM_NORMAL_HINTS</property> property on the specified window.
-The property is stored with a type of <property>WM_SIZE_HINTS</property> and a format of 32.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetWMNormalHints</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To read a window's <property>WM_NORMAL_HINTS</property> property, use
-<function>XGetWMNormalHints</function>.
-<indexterm significance="preferred"><primary>XGetWMNormalHints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetWMNormalHints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *hints_return</parameter></paramdef>
- <paramdef>long<parameter> *supplied_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hints_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the size hints for the window in its normal state.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>supplied_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the hints that were supplied by the user.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetWMNormalHints</function>
-function returns the size hints stored in the <property>WM_NORMAL_HINTS</property> property
-on the specified window.
-If the property is of type <property>WM_SIZE_HINTS</property>, is of format 32,
-and is long enough to contain either an old (pre-<acronym>ICCCM</acronym>)
-or new size hints structure,
-<function>XGetWMNormalHints</function>
-sets the various fields of the
-<structname>XSizeHints</structname>
-structure, sets the supplied_return argument to the list of fields
-that were supplied by the user (whether or not they contained defined values),
-and returns a nonzero status.
-Otherwise, it returns a zero status.
-</para>
-<para>
-<!-- .LP -->
-If
-<function>XGetWMNormalHints</function>
-returns successfully and a pre-<acronym>ICCCM</acronym> size hints property is read,
-the supplied_return argument will contain the following bits:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-(USPosition|USSize|PPosition|PSize|PMinSize|
- PMaxSize|PResizeInc|PAspect)
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-If the property is large enough to contain the base size
-and window gravity fields as well,
-the supplied_return argument will also contain the following bits:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-PBaseSize|PWinGravity
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<function>XGetWMNormalHints</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set a window's <property>WM_SIZE_HINTS</property> property, use
-<function>XSetWMSizeHints</function>.
-<indexterm significance="preferred"><primary>XSetWMSizeHints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XSetWMSizeHints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
- <paramdef>Atom<parameter> property</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XSizeHints</structname>
-structure to be used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>property</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the property name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWMSizeHints</function>
-function replaces the size hints for the specified property
-on the named window.
-If the specified property does not already exist,
-<function>XSetWMSizeHints</function>
-sets the size hints for the specified property
-on the named window.
-The property is stored with a type of <property>WM_SIZE_HINTS</property> and a format of 32.
-To set a window's normal size hints,
-you can use the
-<function>XSetWMNormalHints</function>
-function.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetWMSizeHints</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadAtom</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To read a window's <property>WM_SIZE_HINTS</property> property, use
-<function>XGetWMSizeHints</function>.
-<indexterm significance="preferred"><primary>XGetWMSizeHints</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetWMSizeHints</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *hints_return</parameter></paramdef>
- <paramdef>long<parameter> *supplied_return</parameter></paramdef>
- <paramdef>Atom<parameter> property</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hints_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the
-<structname>XSizeHints</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>supplied_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the hints that were supplied by the user.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>property</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the property name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetWMSizeHints</function>
-function returns the size hints stored in the specified property
-on the named window.
-If the property is of type <property>WM_SIZE_HINTS</property>, is of format 32,
-and is long enough to contain either an old (pre-<acronym>ICCCM</acronym>)
-or new size hints structure,
-<function>XGetWMSizeHints</function>
-sets the various fields of the
-<structname>XSizeHints</structname>
-structure, sets the supplied_return argument to the
-list of fields that were supplied by the user
-(whether or not they contained defined values),
-and returns a nonzero status.
-Otherwise, it returns a zero status.
-To get a window's normal size hints,
-you can use the
-<function>XGetWMNormalHints</function>
-function.
-</para>
-<para>
-<!-- .LP -->
-If
-<function>XGetWMSizeHints</function>
-returns successfully and a pre-<acronym>ICCCM</acronym> size hints property is read,
-the supplied_return argument will contain the following bits:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-(USPosition|USSize|PPosition|PSize|PMinSize|
- PMaxSize|PResizeInc|PAspect)
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-If the property is large enough to contain the base size
-and window gravity fields as well,
-the supplied_return argument will also contain the following bits:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-PBaseSize|PWinGravity
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<function>XGetWMSizeHints</function>
-can generate
-<errorname>BadAtom</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect2>
-<sect2 id="Setting_and_Reading_the_WM_CLASS_Property">
-<title>Setting and Reading the WM_CLASS Property</title>
-<!-- .XS -->
-<!-- (SN Setting and Reading the WM_CLASS Property -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set and get
-the <property>WM_CLASS</property> property for a given window.
-These functions use the
-<structname>XClassHint</structname>
-structure, which is defined in the
-<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
-<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-header file.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To allocate an
-<structname>XClassHint</structname>
-structure, use
-<function>XAllocClassHint</function>.
-<indexterm significance="preferred"><primary>XAllocClassHint</primary></indexterm>
-<!-- .sM -->
-</para>
-<para>
-
- XClassHint *XAllocClassHint()
-</para>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAllocClassHint</function>
-function allocates and returns a pointer to an
-<structname>XClassHint</structname>
-structure.
-Note that the pointer fields in the
-<structname>XClassHint</structname>
-structure are initially set to NULL.
-If insufficient memory is available,
-<function>XAllocClassHint</function>
-returns NULL.
-To free the memory allocated to this structure,
-use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XClassHint</structname>
-contains:
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<indexterm significance="preferred"><primary>XClassHint</primary></indexterm>
-<literallayout class="monospaced">
-<!-- .TA .5i -->
-<!-- .ta .5i -->
-typedef struct {
- char *res_name;
- char *res_class;
-} XClassHint;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The res_name member contains the application name,
-and the res_class member contains the application class.
-Note that the name set in this property may differ from the name set as <property>WM_NAME</property>.
-That is, <property>WM_NAME</property> specifies what should be displayed in the title bar and,
-therefore, can contain temporal information (for example, the name of
-a file currently in an editor's buffer).
-On the other hand,
-the name specified as part of <property>WM_CLASS</property> is the formal name of the application
-that should be used when retrieving the application's resources from the
-resource database.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set a window's <property>WM_CLASS</property> property, use
-<function>XSetClassHint</function>.
-<indexterm significance="preferred"><primary>XSetClassHint</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetClassHint</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XClassHint<parameter> *class_hints</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>class_hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XClassHint</structname>
-structure that is to be used.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetClassHint</function>
-function sets the class hint for the specified window.
-If the strings are not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetClassHint</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To read a window's <property>WM_CLASS</property> property, use
-<function>XGetClassHint</function>.
-<indexterm significance="preferred"><primary>XGetClassHint</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetClassHint</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XClassHint<parameter> *class_hints_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>class_hints_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the
-<structname>XClassHint</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetClassHint</function>
-function returns the class hint of the specified window to the members
-of the supplied structure.
-If the data returned by the server is in the Latin Portable Character Encoding,
-then the returned strings are in the Host Portable Character Encoding.
-Otherwise, the result is implementation-dependent.
-It returns a nonzero status on success;
-otherwise, it returns a zero status.
-To free res_name and res_class when finished with the strings,
-use
-<function>XFree</function>
-on each individually.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetClassHint</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect2>
-<sect2 id="Setting_and_Reading_the_WM_TRANSIENT_FOR_Property">
-<title>Setting and Reading the WM_TRANSIENT_FOR Property</title>
-<!-- .XS -->
-<!-- (SN Setting and Reading the WM_TRANSIENT_FOR Property -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set and read
-the <property>WM_TRANSIENT_FOR</property> property for a given window.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set a window's <property>WM_TRANSIENT_FOR</property> property, use
-<function>XSetTransientForHint</function>.
-<indexterm significance="preferred"><primary>XSetTransientForHint</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetTransientForHint</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Window<parameter> prop_window</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>prop_window</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window that the <property>WM_TRANSIENT_FOR</property> property is to be set to.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetTransientForHint</function>
-function sets the <property>WM_TRANSIENT_FOR</property> property of the specified window to the
-specified prop_window.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetTransientForHint</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To read a window's <property>WM_TRANSIENT_FOR</property> property, use
-<function>XGetTransientForHint</function>.
-<indexterm significance="preferred"><primary>XGetTransientForHint</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetTransientForHint</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Window<parameter> *prop_window_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>prop_window_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the <property>WM_TRANSIENT_FOR</property> property of the specified window.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetTransientForHint</function>
-function returns the <property>WM_TRANSIENT_FOR</property> property for the specified window.
-It returns a nonzero status on success;
-otherwise, it returns a zero status.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetTransientForHint</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect2>
-<sect2 id="Setting_and_Reading_the_WM_PROTOCOLS_Property">
-<title>Setting and Reading the WM_PROTOCOLS Property</title>
-<!-- .XS -->
-<!-- (SN Setting and Reading the WM_PROTOCOLS Property -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set and read
-the <property>WM_PROTOCOLS</property> property for a given window.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set a window's <property>WM_PROTOCOLS</property> property, use
-<function>XSetWMProtocols</function>.
-<indexterm significance="preferred"><primary>XSetWMProtocols</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XSetWMProtocols</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Atom<parameter> *protocols</parameter></paramdef>
- <paramdef>int<parameter> count</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>protocols</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the list of protocols.
-<!-- .ds Cn protocols in the list -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of (Cn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWMProtocols</function>
-function replaces the <property>WM_PROTOCOLS</property> property on the specified window
-with the list of atoms specified by the protocols argument.
-If the property does not already exist,
-<function>XSetWMProtocols</function>
-sets the <property>WM_PROTOCOLS</property> property on the specified window
-to the list of atoms specified by the protocols argument.
-The property is stored with a type of ATOM and a format of 32.
-If it cannot intern the <property>WM_PROTOCOLS</property> atom,
-<function>XSetWMProtocols</function>
-returns a zero status.
-Otherwise, it returns a nonzero status.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetWMProtocols</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To read a window's <property>WM_PROTOCOLS</property> property, use
-<function>XGetWMProtocols</function>.
-<indexterm significance="preferred"><primary>XGetWMProtocols</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetWMProtocols</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Atom<parameter> **protocols_return</parameter></paramdef>
- <paramdef>int<parameter> *count_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>protocols_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the list of protocols.
-<!-- .ds Cn protocols in the list -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of (Cn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetWMProtocols</function>
-function returns the list of atoms stored in the <property>WM_PROTOCOLS</property> property
-on the specified window.
-These atoms describe window manager protocols in which the owner
-of this window is willing to participate.
-If the property exists, is of type ATOM, is of format 32,
-and the atom <property>WM_PROTOCOLS</property> can be interned,
-<function>XGetWMProtocols</function>
-sets the protocols_return argument to a list of atoms,
-sets the count_return argument to the number of elements in the list,
-and returns a nonzero status.
-Otherwise, it sets neither of the return arguments
-and returns a zero status.
-To release the list of atoms, use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetWMProtocols</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect2>
-<sect2 id="Setting_and_Reading_the_WM_COLORMAP_WINDOWS_Property">
-<title>Setting and Reading the WM_COLORMAP_WINDOWS Property</title>
-<!-- .XS -->
-<!-- (SN Setting and Reading the WM_COLORMAP_WINDOWS Property -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set and read
-the <property>WM_COLORMAP_WINDOWS</property> property for a given window.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set a window's <property>WM_COLORMAP_WINDOWS</property> property, use
-<function>XSetWMColormapWindows</function>.
-<indexterm significance="preferred"><primary>XSetWMColormapWindows</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XSetWMColormapWindows</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Window<parameter> *colormap_windows</parameter></paramdef>
- <paramdef>int<parameter> count</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap_windows</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the list of windows.
-<!-- .ds Cn windows in the list -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of (Cn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWMColormapWindows</function>
-function replaces the <property>WM_COLORMAP_WINDOWS</property> property on the specified
-window with the list of windows specified by the colormap_windows argument.
-If the property does not already exist,
-<function>XSetWMColormapWindows</function>
-sets the <property>WM_COLORMAP_WINDOWS</property> property on the specified
-window to the list of windows specified by the colormap_windows argument.
-The property is stored with a type of WINDOW and a format of 32.
-If it cannot intern the <property>WM_COLORMAP_WINDOWS</property> atom,
-<function>XSetWMColormapWindows</function>
-returns a zero status.
-Otherwise, it returns a nonzero status.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetWMColormapWindows</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To read a window's <property>WM_COLORMAP_WINDOWS</property> property, use
-<function>XGetWMColormapWindows</function>.
-<indexterm significance="preferred"><primary>XGetWMColormapWindows</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetWMColormapWindows</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>Window<parameter> **colormap_windows_return</parameter></paramdef>
- <paramdef>int<parameter> *count_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>colormap_windows_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the list of windows.
-<!-- .ds Cn windows in the list -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of (Cn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetWMColormapWindows</function>
-function returns the list of window identifiers stored
-in the <property>WM_COLORMAP_WINDOWS</property> property on the specified window.
-These identifiers indicate the colormaps that the window manager
-may need to install for this window.
-If the property exists, is of type WINDOW, is of format 32,
-and the atom <property>WM_COLORMAP_WINDOWS</property> can be interned,
-<function>XGetWMColormapWindows</function>
-sets the windows_return argument to a list of window identifiers,
-sets the count_return argument to the number of elements in the list,
-and returns a nonzero status.
-Otherwise, it sets neither of the return arguments
-and returns a zero status.
-To release the list of window identifiers, use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetWMColormapWindows</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect2>
-<sect2 id="Setting_and_Reading_the_WM_ICON_SIZE_Property">
-<title>Setting and Reading the WM_ICON_SIZE Property</title>
-<!-- .XS -->
-<!-- (SN Setting and Reading the WM_ICON_SIZE Property -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set and read
-the <property>WM_ICON_SIZE</property> property for a given window.
-These functions use the
-<structname>XIconSize</structname>
-<indexterm><primary>XIconSize</primary></indexterm>
-structure, which is defined in the
-<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
-<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-header file.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To allocate an
-<structname>XIconSize</structname>
-structure, use
-<function>XAllocIconSize</function>.
-</para>
-
-<para>
- XIconSize *XAllocIconSize()
-</para>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAllocIconSize</function>
-function allocates and returns a pointer to an
-<structname>XIconSize</structname>
-structure.
-Note that all fields in the
-<structname>XIconSize</structname>
-structure are initially set to zero.
-If insufficient memory is available,
-<function>XAllocIconSize</function>
-returns NULL.
-To free the memory allocated to this structure,
-use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XIconSize</structname>
-structure contains:
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<indexterm significance="preferred"><primary>XIconSize</primary></indexterm>
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- int min_width, min_height;
- int max_width, max_height;
- int width_inc, height_inc;
-} XIconSize;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The width_inc and height_inc members define an arithmetic progression of
-sizes (minimum to maximum) that represent the supported icon sizes.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set a window's <property>WM_ICON_SIZE</property> property, use
-<function>XSetIconSizes</function>.
-<indexterm significance="preferred"><primary>XSetIconSizes</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetIconSizes</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XIconSize<parameter> *size_list</parameter></paramdef>
- <paramdef>int<parameter> count</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>size_list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the size list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of items in the size list.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetIconSizes</function>
-function is used only by window managers to set the supported icon sizes.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetIconSizes</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To read a window's <property>WM_ICON_SIZE</property> property, use
-<function>XGetIconSizes</function>.
-<indexterm significance="preferred"><primary>XGetIconSizes</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetIconSizes</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XIconSize<parameter> **size_list_return</parameter></paramdef>
- <paramdef>int<parameter> *count_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>size_list_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the size list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of items in the size list.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetIconSizes</function>
-function returns zero if a window manager has not set icon sizes;
-otherwise, it returns nonzero.
-<function>XGetIconSizes</function>
-should be called by an application that
-wants to find out what icon sizes would be most appreciated by the
-window manager under which the application is running.
-The application
-should then use
-<function>XSetWMHints</function>
-to supply the window manager with an icon pixmap or window in one of the
-supported sizes.
-To free the data allocated in size_list_return, use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetIconSizes</function>
-can generate a
-<errorname>BadWindow</errorname>
-error.
-</para>
-</sect2>
-<sect2 id="Using_Window_Manager_Convenience_Functions">
-<title>Using Window Manager Convenience Functions</title>
-<!-- .XS -->
-<!-- (SN Using Window Manager Convenience Functions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<function>XmbSetWMProperties</function>
-function stores the standard set of window manager properties,
-with text properties in standard encodings
-for internationalized text communication.
-The standard window manager properties for a given window are
-<property>WM_NAME</property>, <property>WM_ICON_NAME</property>, <property>WM_HINTS</property>, <property>WM_NORMAL_HINTS</property>, <property>WM_CLASS</property>,
-<property>WM_COMMAND</property>, <property>WM_CLIENT_MACHINE</property>, and <property>WM_LOCALE_NAME</property>.
-<indexterm significance="preferred"><primary>XmbSetWMProperties</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XmbSetWMProperties</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>char<parameter> *window_name</parameter></paramdef>
- <paramdef>char<parameter> *icon_name</parameter></paramdef>
- <paramdef>char<parameter> *argv[]</parameter></paramdef>
- <paramdef>int<parameter> argc</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *normal_hints</parameter></paramdef>
- <paramdef>XWMHints<parameter> *wm_hints</parameter></paramdef>
- <paramdef>XClassHint<parameter> *class_hints</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>window_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window name,
-which should be a null-terminated string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>icon_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the icon name,
-which should be a null-terminated string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>argv</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the application's argument list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>argc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of arguments.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the size hints for the window in its normal state.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>wm_hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XWMHints</structname>
-structure to be used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>class_hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XClassHint</structname>
-structure to be used.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XmbSetWMProperties</function>
-convenience function provides a simple programming interface
-for setting those essential window properties that are used
-for communicating with other clients
-(particularly window and session managers).
-</para>
-<para>
-<!-- .LP -->
-If the window_name argument is non-NULL,
-<function>XmbSetWMProperties</function>
-sets the <property>WM_NAME</property> property.
-If the icon_name argument is non-NULL,
-<function>XmbSetWMProperties</function>
-sets the <property>WM_ICON_NAME</property> property.
-The window_name and icon_name arguments are null-terminated strings
-in the encoding of the current locale.
-If the arguments can be fully converted to the STRING encoding,
-the properties are created with type ``STRING'';
-otherwise, the arguments are converted to Compound Text,
-and the properties are created with type ``COMPOUND_TEXT''.
-</para>
-<para>
-<!-- .LP -->
-If the normal_hints argument is non-NULL,
-<function>XmbSetWMProperties</function>
-calls
-<function>XSetWMNormalHints</function>,
-which sets the <property>WM_NORMAL_HINTS</property> property (see section 14.1.7).
-If the wm_hints argument is non-NULL,
-<function>XmbSetWMProperties</function>
-calls
-<function>XSetWMHints</function>,
-which sets the <property>WM_HINTS</property> property (see section 14.1.6).
-</para>
-<para>
-<!-- .LP -->
-If the argv argument is non-NULL,
-<function>XmbSetWMProperties</function>
-sets the <property>WM_COMMAND</property> property from argv and argc.
-An argc of zero indicates a zero-length command.
-</para>
-<para>
-<!-- .LP -->
-The hostname of the machine is stored using
-<function>XSetWMClientMachine</function>
-(see section 14.2.2).
-</para>
-<para>
-<!-- .LP -->
-If the class_hints argument is non-NULL,
-<function>XmbSetWMProperties</function>
-sets the <property>WM_CLASS</property> property.
-If the res_name member in the
-<structname>XClassHint</structname>
-structure is set to the NULL pointer and the RESOURCE_NAME
-environment variable is set,
-the value of the environment variable is substituted for res_name.
-If the res_name member is NULL,
-the environment variable is not set, and argv and argv[0] are set,
-then the value of argv[0], stripped of any directory prefixes,
-is substituted for res_name.
-</para>
-<para>
-<!-- .LP -->
-It is assumed that the supplied class_hints.res_name and argv,
-the RESOURCE_NAME environment variable, and the hostname of the machine
-are in the encoding of the locale announced for the LC_CTYPE category
-(on <acronym>POSIX</acronym>-compliant systems, the LC_CTYPE, else LANG environment variable).
-The corresponding <property>WM_CLASS</property>, <property>WM_COMMAND</property>, and <property>WM_CLIENT_MACHINE</property> properties
-are typed according to the local host locale announcer.
-No encoding conversion is performed prior to storage in the properties.
-</para>
-<para>
-<!-- .LP -->
-For clients that need to process the property text in a locale,
-<function>XmbSetWMProperties</function>
-sets the <property>WM_LOCALE_NAME</property> property to be the name of the current locale.
-The name is assumed to be in the Host Portable Character Encoding
-and is converted to STRING for storage in the property.
-</para>
-<para>
-<!-- .LP -->
-<function>XmbSetWMProperties</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set a window's standard window manager properties
-with strings in client-specified encodings, use
-<function>XSetWMProperties</function>.
-The standard window manager properties for a given window are
-<property>WM_NAME</property>, <property>WM_ICON_NAME</property>, <property>WM_HINTS</property>, <property>WM_NORMAL_HINTS</property>, <property>WM_CLASS</property>,
-<property>WM_COMMAND</property>, and <property>WM_CLIENT_MACHINE</property>.
-<indexterm significance="preferred"><primary>XSetWMProperties</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XSetWMProperties</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *window_name</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *icon_name</parameter></paramdef>
- <paramdef>char<parameter> **argv</parameter></paramdef>
- <paramdef>int<parameter> argc</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *normal_hints</parameter></paramdef>
- <paramdef>XWMHints<parameter> *wm_hints</parameter></paramdef>
- <paramdef>XClassHint<parameter> *class_hints</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>window_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window name,
-which should be a null-terminated string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>icon_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the icon name,
-which should be a null-terminated string.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>argv</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the application's argument list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>argc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of arguments.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>normal_hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the size hints for the window in its normal state.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>wm_hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XWMHints</structname>
-structure to be used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>class_hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XClassHint</structname>
-structure to be used.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWMProperties</function>
-convenience function provides a single programming interface
-for setting those essential window properties that are used
-for communicating with other clients (particularly window and session
-managers).
-</para>
-<para>
-<!-- .LP -->
-If the window_name argument is non-NULL,
-<function>XSetWMProperties</function>
-calls
-<function>XSetWMName</function>,
-which, in turn, sets the <property>WM_NAME</property> property (see section 14.1.4).
-If the icon_name argument is non-NULL,
-<function>XSetWMProperties</function>
-calls
-<function>XSetWMIconName</function>,
-which sets the <property>WM_ICON_NAME</property> property (see section 14.1.5).
-If the argv argument is non-NULL,
-<function>XSetWMProperties</function>
-calls
-<function>XSetCommand</function>,
-which sets the <property>WM_COMMAND</property> property (see section 14.2.1).
-Note that an argc of zero is allowed to indicate a zero-length command.
-Note also that the hostname of this machine is stored using
-<function>XSetWMClientMachine</function>
-(see section 14.2.2).
-</para>
-<para>
-<!-- .LP -->
-If the normal_hints argument is non-NULL,
-<function>XSetWMProperties</function>
-calls
-<function>XSetWMNormalHints</function>,
-which sets the <property>WM_NORMAL_HINTS</property> property (see section 14.1.7).
-If the wm_hints argument is non-NULL,
-<function>XSetWMProperties</function>
-calls
-<function>XSetWMHints</function>,
-which sets the <property>WM_HINTS</property> property (see section 14.1.6).
-</para>
-<para>
-<!-- .LP -->
-If the class_hints argument is non-NULL,
-<function>XSetWMProperties</function>
-calls
-<function>XSetClassHint</function>,
-which sets the <property>WM_CLASS</property> property (see section 14.1.8).
-If the res_name member in the
-<structname>XClassHint</structname>
-structure is set to the NULL pointer and the RESOURCE_NAME environment
-variable is set,
-then the value of the environment variable is substituted for res_name.
-If the res_name member is NULL,
-the environment variable is not set,
-and argv and argv[0] are set,
-then the value of argv[0], stripped of
-any directory prefixes, is substituted for res_name.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetWMProperties</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Client_to_Session_Manager_Communication">
-<title>Client to Session Manager Communication</title>
-<!-- .XS -->
-<!-- (SN Client to Session Manager Communication -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This section discusses how to:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Set and read the <property>WM_COMMAND</property> property
- </para>
- </listitem>
- <listitem>
- <para>
-Set and read the <property>WM_CLIENT_MACHINE</property> property
- </para>
- </listitem>
-</itemizedlist>
-<sect2 id="Setting_and_Reading_the_WM_COMMAND_Property">
-<title>Setting and Reading the WM_COMMAND Property</title>
-<!-- .XS -->
-<!-- (SN Setting and Reading the WM_COMMAND Property -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set and read
-the <property>WM_COMMAND</property> property for a given window.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set a window's <property>WM_COMMAND</property> property, use
-<function>XSetCommand</function>.
-<indexterm significance="preferred"><primary>XSetCommand</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetCommand</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>char<parameter> **argv</parameter></paramdef>
- <paramdef>int<parameter> argc</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>argv</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the application's argument list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>argc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of arguments.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetCommand</function>
-function sets the command and arguments used to invoke the
-application.
-(Typically, argv is the argv array of your main program.)
-If the strings are not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-<function>XSetCommand</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To read a window's <property>WM_COMMAND</property> property, use
-<function>XGetCommand</function>.
-<indexterm significance="preferred"><primary>XGetCommand</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetCommand</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>char<parameter> ***argv_return</parameter></paramdef>
- <paramdef>int<parameter> *argc_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>argv_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the application's argument list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>argc_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of arguments returned.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetCommand</function>
-function reads the <property>WM_COMMAND</property> property from the specified window
-and returns a string list.
-If the <property>WM_COMMAND</property> property exists,
-it is of type STRING and format 8.
-If sufficient memory can be allocated to contain the string list,
-<function>XGetCommand</function>
-fills in the argv_return and argc_return arguments
-and returns a nonzero status.
-Otherwise, it returns a zero status.
-If the data returned by the server is in the Latin Portable Character Encoding,
-then the returned strings are in the Host Portable Character Encoding.
-Otherwise, the result is implementation-dependent.
-To free the memory allocated to the string list, use
-<function>XFreeStringList</function>.
-</para>
-</sect2>
-<sect2 id="Setting_and_Reading_the_WM_CLIENT_MACHINE_Property">
-<title>Setting and Reading the WM_CLIENT_MACHINE Property</title>
-<!-- .XS -->
-<!-- (SN Setting and Reading the WM_CLIENT_MACHINE Property -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set and read
-the <property>WM_CLIENT_MACHINE</property> property for a given window.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set a window's <property>WM_CLIENT_MACHINE</property> property, use
-<function>XSetWMClientMachine</function>.
-<indexterm significance="preferred"><primary>XSetWMClientMachine</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XSetWMClientMachine</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>text_prop</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XTextProperty</structname>
-structure to be used.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetWMClientMachine</function>
-convenience function calls
-<function>XSetTextProperty</function>
-to set the <property>WM_CLIENT_MACHINE</property> property.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To read a window's <property>WM_CLIENT_MACHINE</property> property, use
-<function>XGetWMClientMachine</function>.
-<indexterm significance="preferred"><primary>XGetWMClientMachine</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetWMClientMachine</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>text_prop_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the
-<structname>XTextProperty</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetWMClientMachine</function>
-convenience function performs an
-<function>XGetTextProperty</function>
-on the <property>WM_CLIENT_MACHINE</property> property.
-It returns a nonzero status on success;
-otherwise, it returns a zero status.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Standard_Colormaps">
-<title>Standard Colormaps</title>
-<!-- .XS -->
-<!-- (SN Standard Colormaps -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Applications with color palettes, smooth-shaded drawings, or digitized
-images demand large numbers of colors.
-In addition, these applications often require an efficient mapping
-from color triples to pixel values that display the appropriate colors.
-</para>
-<para>
-<!-- .LP -->
-As an example, consider a three-dimensional display program that wants
-to draw a smoothly shaded sphere.
-At each pixel in the image of the sphere,
-the program computes the intensity and color of light
-reflected back to the viewer.
-The result of each computation is a triple of red, green, and blue (<acronym>RGB</acronym>)
-coefficients in the range 0.0 to 1.0.
-To draw the sphere, the program needs a colormap that provides a
-large range of uniformly distributed colors.
-The colormap should be arranged so that the program can
-convert its <acronym>RGB</acronym> triples into pixel values very quickly,
-because drawing the entire sphere requires many such
-conversions.
-</para>
-<para>
-<!-- .LP -->
-On many current workstations,
-the display is limited to 256 or fewer colors.
-Applications must allocate colors carefully,
-not only to make sure they cover the entire range they need
-but also to make use of as many of the available colors as possible.
-On a typical X display,
-many applications are active at once.
-Most workstations have only one hardware look-up table for colors,
-so only one application colormap can be installed at a given time.
-The application using the installed colormap is displayed correctly,
-and the other applications go technicolor and are
-displayed with false colors.
-</para>
-<para>
-<!-- .LP -->
-As another example, consider a user who is running an
-image processing program to display earth-resources data.
-The image processing program needs a colormap set up with 8 reds,
-8 greens, and 4 blues, for a total of 256 colors.
-Because some colors are already in use in the default colormap,
-the image processing program allocates and installs a new colormap.
-</para>
-<para>
-<!-- .LP -->
-The user decides to alter some of the colors in the image
-by invoking a color palette program to mix and choose colors.
-The color palette program also needs a
-colormap with eight reds, eight greens, and four blues, so just like
-the image processing program, it must allocate and
-install a new colormap.
-</para>
-<para>
-<!-- .LP -->
-Because only one colormap can be installed at a time,
-the color palette may be displayed incorrectly
-whenever the image processing program is active.
-Conversely, whenever the palette program is active,
-the image may be displayed incorrectly.
-The user can never match or compare colors in the palette and image.
-Contention for colormap resources can be reduced if applications
-with similar color needs share colormaps.
-</para>
-<para>
-<!-- .LP -->
-The image processing program and the color palette program
-could share the same colormap if there existed a convention that described
-how the colormap was set up.
-Whenever either program was active,
-both would be displayed correctly.
-</para>
-<para>
-<!-- .LP -->
-The standard colormap properties define a set of commonly used
-colormaps.
-Applications that share these colormaps and conventions display
-true colors more often and provide a better interface to the user.
-</para>
-<para>
-<!-- .LP -->
-Standard colormaps allow applications to share commonly used color
-resources.
-This allows many applications to be displayed in true colors
-simultaneously, even when each application needs an entirely filled
-colormap.
-</para>
-<para>
-<!-- .LP -->
-Several standard colormaps are described in this section.
-Usually, a window manager creates these colormaps.
-Applications should use the standard colormaps if they already exist.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To allocate an
-<structname>XStandardColormap</structname>
-structure, use
-<function>XAllocStandardColormap</function>.
-</para>
-
-<para>
-XStandardColormap *XAllocStandardColormap()
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAllocStandardColormap</function>
-function allocates and returns a pointer to an
-<structname>XStandardColormap</structname>
-structure.
-Note that all fields in the
-<structname>XStandardColormap</structname>
-structure are initially set to zero.
-If insufficient memory is available,
-<function>XAllocStandardColormap</function>
-returns NULL.
-To free the memory allocated to this structure,
-use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XStandardColormap</structname>
-structure contains:
-</para>
-<literallayout class="monospaced">
-/* Hints */
-
-#define ReeaseByFreeingColormap ((XID)1L)
-
-/* Values */
-
-typedef struct {
- Colormap colormap;
- unsigned long red_max;
- unsigned long red_mult;
- unsigned long green_max;
- unsigned long green_mult;
- unsigned long blue_max;
- unsigned long blue_mult;
- unsigned long base_pixel;
- VisualID visualid;
- XID killid;
-} XStandardColormap;
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The colormap member is the colormap created by the
-<function>XCreateColormap</function>
-function.
-The red_max, green_max, and blue_max members give the maximum
-red, green, and blue values, respectively.
-Each color coefficient ranges from zero to its max, inclusive.
-For example,
-a common colormap allocation is 3/3/2 (3 planes for red, 3
-planes for green, and 2 planes for blue).
-This colormap would have red_max = 7, green_max = 7,
-and blue_max = 3.
-An alternate allocation that uses only 216 colors is red_max = 5,
-green_max = 5, and blue_max = 5.
-</para>
-<para>
-<!-- .LP -->
-The red_mult, green_mult, and blue_mult members give the
-scale factors used to compose a full pixel value.
-(See the discussion of the base_pixel members for further information.)
-For a 3/3/2 allocation, red_mult might be 32,
-green_mult might be 4, and blue_mult might be 1.
-For a 6-colors-each allocation, red_mult might be 36,
-green_mult might be 6, and blue_mult might be 1.
-</para>
-<para>
-<!-- .LP -->
-The base_pixel member gives the base pixel value used to
-compose a full pixel value.
-Usually, the base_pixel is obtained from a call to the
-<function>XAllocColorPlanes</function>
-function.
-Given integer red, green, and blue coefficients in their appropriate
-ranges, one then can compute a corresponding pixel value by
-using the following expression:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 1.5i -->
-<!-- .ta .5i 1.5i -->
-(r * red_mult + g * green_mult + b * blue_mult + base_pixel) &amp; 0xFFFFFFFF
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-For
-<symbol>GrayScale</symbol>
-colormaps,
-only the colormap, red_max, red_mult,
-and base_pixel members are defined.
-The other members are ignored.
-To compute a
-<symbol>GrayScale</symbol>
-pixel value, use the following expression:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .5i 1.5i -->
-<!-- .ta .5i 1.5i -->
-(gray * red_mult + base_pixel) &amp; 0xFFFFFFFF
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-Negative multipliers can be represented by converting the 2's
-complement representation of the multiplier into an unsigned long and
-storing the result in the appropriate _mult field.
-The step of masking by 0xFFFFFFFF effectively converts the resulting
-positive multiplier into a negative one.
-The masking step will take place automatically on many machine architectures,
-depending on the size of the integer type used to do the computation.
-</para>
-<para>
-<!-- .LP -->
-The visualid member gives the ID number of the visual from which the
-colormap was created.
-The killid member gives a resource ID that indicates whether
-the cells held by this standard colormap are to be released
-by freeing the colormap ID or by calling the
-<function>XKillClient</function>
-function on the indicated resource.
-(Note that this method is necessary for allocating out of an existing colormap.)
-</para>
-<para>
-<!-- .LP -->
-The properties containing the
-<structname>XStandardColormap</structname>
-information have
-the type RGB_COLOR_MAP.
-</para>
-<para>
-<!-- .LP -->
-The remainder of this section discusses standard colormap properties and atoms
-as well as how to manipulate standard colormaps.
-</para>
-<sect2 id="Standard_Colormap_Properties_and_Atoms">
-<title>Standard Colormap Properties and Atoms</title>
-<!-- .XS -->
-<!-- (SN Standard Colormap Properties and Atoms -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Standard Colormaps</primary></indexterm>
-<indexterm><primary>Colormaps</primary><secondary>standard</secondary></indexterm>
-Several standard colormaps are available.
-Each standard colormap is defined by a property,
-and each such property is identified by an atom.
-The following list names the atoms and describes the colormap
-associated with each one.
-The
-<filename class="headerfile">&lt;X11/Xatom.h&gt;</filename>
-<indexterm type="file"><primary><filename class="headerfile">X11/Xatom.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xatom.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xatom.h&gt;</filename></secondary></indexterm>
-header file contains the definitions for each of the following atoms,
-which are prefixed with XA_.
-</para>
-
-
-
-<variablelist>
- <varlistentry>
- <term>RGB_DEFAULT_MAP</term>
- <listitem>
- <para>
-This atom names a property.
-The value of the property is an array of
-<structname>XStandardColormap</structname>
-structures.
-Each entry in the array describes an <acronym>RGB</acronym> subset of the default color
-map for the Visual specified by visual_id.
- </para>
- <para>
-Some applications only need a few <acronym>RGB</acronym> colors and
-may be able to allocate them from the system default colormap.
-This is the ideal situation because the fewer colormaps that are
-active in the system the more applications are displayed
-with correct colors at all times.
- </para>
- <para>
-A typical allocation for the RGB_DEFAULT_MAP on 8-plane displays
-is 6 reds, 6 greens, and 6 blues.
-This gives 216 uniformly distributed colors
-(6 intensities of 36 different hues) and still leaves 40 elements
-of a 256-element colormap available for special-purpose colors
-for text, borders, and so on.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>RGB_BEST_MAP</term>
- <listitem>
- <para>
-This atom names a property. The value of the property is an
-<structname>XStandardColormap</structname>.
- </para>
- <para>
-The property defines the best <acronym>RGB</acronym> colormap available on
-the screen.
-(Of course, this is a subjective evaluation.)
-Many image processing and three-dimensional applications need to
-use all available colormap cells and to distribute as many
-perceptually distinct colors as possible over those cells.
-This implies that there may be more green values available than
-red, as well as more green or red than blue.
- </para>
- <para>
-For an 8-plane
-<symbol>PseudoColor</symbol>
-visual,
-RGB_BEST_MAP is likely to be a 3/3/2 allocation.
-For a 24-plane
-<symbol>DirectColor</symbol>
-visual,
-RGB_BEST_MAP is normally an 8/8/8 allocation.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>RGB_RED_MAP,RGB_GREEN_MAP,RGB_BLUE_MAP</term>
- <listitem>
- <para>
-These atoms name properties.
-The value of each property is an
-<structname>XStandardColormap</structname>.
- </para>
- <para>
-The properties define all-red, all-green, and all-blue
-colormaps, respectively.
-These maps are used by applications that want to make color-separated
-images.
-For example, a user might generate a full-color image
-on an 8-plane display both by rendering an image three times
-(once with high color resolution in red, once with green,
-and once with blue) and by multiply exposing a single frame in a camera.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>RGB_GRAY_MAP</term>
- <listitem>
- <para>
-This atom names a property.
-The value of the property is an
-<structname>XStandardColormap</structname>.
- </para>
- <para>
-The property describes the best
-<symbol>GrayScale</symbol>
-colormap available on the screen.
-As previously mentioned,
-only the colormap, red_max, red_mult, and base_pixel members of the
-<structname>XStandardColormap</structname>
-structure are used for
-<symbol>GrayScale</symbol>
-colormaps.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-</sect2>
-
-<sect2 id="Setting_and_Obtaining_Standard_Colormaps">
-<title>Setting and Obtaining Standard Colormaps</title>
-<!-- .XS -->
-<!-- (SN Setting and Obtaining Standard Colormaps -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to set and obtain an
-<structname>XStandardColormap</structname>
-structure.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To set an
-<structname>XStandardColormap</structname>
-structure, use
-<function>XSetRGBColormaps</function>.
-<indexterm significance="preferred"><primary>XSetRGBColormaps</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XSetRGBColormaps</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XStandardColormap<parameter> *std_colormap</parameter></paramdef>
- <paramdef>int<parameter> count</parameter></paramdef>
- <paramdef>Atom<parameter> property</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>std_colormap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>XStandardColormap</structname>
-structure to be used.
-<!-- .ds Cn colormaps -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of (Cn.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>property</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the property name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetRGBColormaps</function>
-function replaces the <acronym>RGB</acronym> colormap definition in the specified property
-on the named window.
-If the property does not already exist,
-<function>XSetRGBColormaps</function>
-sets the <acronym>RGB</acronym> colormap definition in the specified property
-on the named window.
-The property is stored with a type of RGB_COLOR_MAP and a format of 32.
-Note that it is the caller's responsibility to honor the <acronym>ICCCM</acronym>
-restriction that only RGB_DEFAULT_MAP contain more than one definition.
-</para>
-<para>
-<!-- .LP -->
-The
-<function>XSetRGBColormaps</function>
-function usually is only used by window or session managers.
-To create a standard colormap,
-follow this procedure:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Open a new connection to the same server.
- </para>
- </listitem>
- <listitem>
- <para>
-Grab the server.
- </para>
- </listitem>
- <listitem>
- <para>
-See if the property is on the property list of the root window for the screen.
- </para>
- </listitem>
- <listitem>
- <para>
-If the desired property is not present:
-<!-- .RS -->
- </para>
- </listitem>
- <listitem>
- <para>
-Create a colormap (unless you are using the default colormap of the screen).
- </para>
- </listitem>
- <listitem>
- <para>
-Determine the color characteristics of the visual.
- </para>
- </listitem>
- <listitem>
- <para>
-Allocate cells in the colormap (or create it with
-<symbol>AllocAll</symbol>).
- </para>
- </listitem>
- <listitem>
- <para>
-Call
-<function>XStoreColors</function>
-to store appropriate color values in the colormap.
- </para>
- </listitem>
- <listitem>
- <para>
-Fill in the descriptive members in the
-<structname>XStandardColormap</structname>
-structure.
- </para>
- </listitem>
- <listitem>
- <para>
-Attach the property to the root window.
- </para>
- </listitem>
- <listitem>
- <para>
-Use
-<function>XSetCloseDownMode</function>
-to make the resource permanent.
-<!-- .RE -->
- </para>
- </listitem>
- <listitem>
- <para>
-Ungrab the server.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-<function>XSetRGBColormaps</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadAtom</errorname>,
-and
-<errorname>BadWindow</errorname>
-errors.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To obtain the
-<structname>XStandardColormap</structname>
-structure associated with the specified property, use
-<function>XGetRGBColormaps</function>.
-<indexterm significance="preferred"><primary>XGetRGBColormaps</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XGetRGBColormaps</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Window<parameter> w</parameter></paramdef>
- <paramdef>XStandardColormap<parameter> **std_colormap_return</parameter></paramdef>
- <paramdef>int<parameter> *count_return</parameter></paramdef>
- <paramdef>Atom<parameter> property</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>w</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the window.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>std_colormap_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the
-<structname>XStandardColormap</structname>
-structure.
-<!-- .ds Cn colormaps -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>count_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of (Cn.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>property</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the property name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetRGBColormaps</function>
-function returns the <acronym>RGB</acronym> colormap definitions stored
-in the specified property on the named window.
-If the property exists, is of type RGB_COLOR_MAP, is of format 32,
-and is long enough to contain a colormap definition,
-<function>XGetRGBColormaps</function>
-allocates and fills in space for the returned colormaps
-and returns a nonzero status.
-If the visualid is not present,
-<function>XGetRGBColormaps</function>
-assumes the default visual for the screen on which the window is located;
-if the killid is not present,
-<symbol>None</symbol>
-is assumed, which indicates that the resources cannot be released.
-Otherwise,
-none of the fields are set, and
-<function>XGetRGBColormaps</function>
-returns a zero status.
-Note that it is the caller's responsibility to honor the <acronym>ICCCM</acronym>
-restriction that only RGB_DEFAULT_MAP contain more than one definition.
-</para>
-<para>
-<!-- .LP -->
-<function>XGetRGBColormaps</function>
-can generate
-<errorname>BadAtom</errorname>
-and
-<errorname>BadWindow</errorname>
-errors.
-<!-- .bp -->
-
-</para>
-</sect2>
-</sect1>
-</chapter>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<chapter id="inter_client_communication_functions">
+<title>Inter-Client Communication Functions</title>
+<para>
+The Inter-Client Communication Conventions Manual, hereafter referred to as the <acronym>ICCCM</acronym>,
+details the X Consortium approved conventions that govern inter-client communications. These
+conventions ensure peer-to-peer client cooperation in the use of selections, cut buffers, and shared
+resources as well as client cooperation with window and session managers. For further information,
+see the Inter-Client Communication Conventions Manual.
+</para>
+<para>
+Xlib provides a number of standard properties and programming interfaces that are <acronym>ICCCM</acronym>
+compliant. The predefined atoms for some of these properties are defined in the &lt;X11/Xatom.h&gt;
+header file, where to avoid name conflicts with user symbols their #define name has an XA_ prefix.
+For further information about atoms and properties, see section 4.3.
+</para>
+<para>
+Xlib’s selection and cut buffer mechanisms provide the primary programming interfaces by which
+peer client applications communicate with each other (see sections 4.5 and 16.6). The functions
+discussed in this chapter provide the primary programming interfaces by which client applications
+communicate with their window and session managers as well as share standard colormaps.
+</para>
+<para>
+The standard properties that are of special interest for communicating with window and session
+managers are:
+</para>
+
+<informaltable>
+ <tgroup cols='4' align='center'>
+ <colspec colname='c1'/>
+ <colspec colname='c2'/>
+ <colspec colname='c3'/>
+ <colspec colname='c4'/>
+ <thead>
+ <row>
+ <entry>Name</entry>
+ <entry>Type</entry>
+ <entry>Format</entry>
+ <entry>Description</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><property>WM_CLASS</property></entry>
+ <entry>STRING</entry>
+ <entry>8</entry>
+ <entry>Set by application programs to allow
+ window and session managers to
+ obtain the application’s resources
+ from the resource database.
+ </entry>
+ </row>
+ <row>
+ <entry><property>WM_CLIENT_MACHINE</property></entry>
+ <entry>TEXT</entry>
+ <entry></entry>
+ <entry>The string name of the machine on
+ which the client application is running.
+ </entry>
+ </row>
+ <row>
+ <entry><property>WM_COLORMAP_WINDOWS</property></entry>
+ <entry>WINDOWS</entry>
+ <entry>32</entry>
+ <entry>The list of window IDs that may
+ need a different colormap from that
+ of their top-level window.
+ </entry>
+ </row>
+ <row>
+ <entry><property>WM_COMMAND</property></entry>
+ <entry>TEXT</entry>
+ <entry></entry>
+ <entry>The command and arguments, null
+ separated, used to invoke the application.
+ </entry>
+ </row>
+ <row>
+ <entry><property>WM_HINTS</property></entry>
+ <entry><property>WM_HINTS</property></entry>
+ <entry>32</entry>
+ <entry>Additional hints set by the client for
+ use by the window manager. The C
+ type of this property is XWMHints.
+ </entry>
+ </row>
+ <row>
+ <entry><property>WM_ICON_NAME</property></entry>
+ <entry>TEXT</entry>
+ <entry></entry>
+ <entry>The name to be used in an icon.</entry>
+ </row>
+ <row>
+ <entry><property>WM_ICON_SIZE</property></entry>
+ <entry><property>WM_ICON_SIZE</property></entry>
+ <entry>32</entry>
+ <entry>The window manager may set this
+ property on the root window to
+ specify the icon sizes it supports.
+ The C type of this property is
+ XIconSize.
+ </entry>
+ </row>
+ <row>
+ <entry><property>WM_NAME</property></entry>
+ <entry>TEXT</entry>
+ <entry></entry>
+ <entry>The name of the application.</entry>
+ </row>
+ <row>
+ <entry><property>WM_NORMAL_HINTS</property></entry>
+ <entry><property>WM_NORMAL_HINTS</property></entry>
+ <entry>32</entry>
+ <entry>Size hints for a window in its
+ normal state. The C type of this
+ property is XSizeHints.
+ </entry>
+ </row>
+ <row>
+ <entry><property>WM_PROTOCOLS</property></entry>
+ <entry>ATOM</entry>
+ <entry>32</entry>
+ <entry>List of atoms that identify the
+ communications protocols between the
+ client and window manager in
+ which the client is willing to participate.
+ </entry>
+ </row>
+ <row>
+ <entry><property>WM_STATE</property></entry>
+ <entry><property>WM_STATE</property></entry>
+ <entry>32</entry>
+ <entry>Intended for communication
+ between window and session managers only.
+ </entry>
+ </row>
+ <row>
+ <entry><property>WM_TRANSIENT_FOR</property></entry>
+ <entry>WINDOW</entry>
+ <entry>32</entry>
+ <entry>Set by application programs to
+ indicate to the window manager that a
+ transient top-level window, such as a
+ dialog box.
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+</informaltable>
+
+<para>
+The remainder of this chapter discusses:
+</para>
+
+<itemizedlist>
+ <listitem><para>Client to window manager communication</para></listitem>
+ <listitem><para>Client to session manager communication</para></listitem>
+ <listitem><para>Standard colormaps</para></listitem>
+</itemizedlist>
+
+<sect1 id="Client_to_Window_Manager_Communication">
+<title>Client to Window Manager Communication</title>
+<!-- .XS -->
+<!-- (SN Client to Window Manager Communication -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This section discusses how to:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Manipulate top-level windows
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Convert string lists
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and read text properties
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and read the <property>WM_NAME</property> property
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and read the <property>WM_ICON_NAME</property> property
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and read the <property>WM_HINTS</property> property
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and read the <property>WM_NORMAL_HINTS</property> property
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and read the <property>WM_CLASS</property> property
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and read the <property>WM_TRANSIENT_FOR</property> property
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and read the <property>WM_PROTOCOLS</property> property
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and read the <property>WM_COLORMAP_WINDOWS</property> property
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and read the <property>WM_ICON_SIZE</property> property
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Use window manager convenience functions
+ </para>
+ </listitem>
+</itemizedlist>
+<sect2 id="Manipulating_Top_Level_Windows">
+<title>Manipulating Top-Level Windows</title>
+<!-- .XS -->
+<!-- (SN Manipulating Top-Level Windows -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to change the visibility or size
+of top-level windows (that is, those that were created as children
+of the root window).
+Note that the subwindows that you create are ignored by window managers.
+Therefore,
+you should use the basic window functions described in chapter 3
+to manipulate your application's subwindows.
+</para>
+<para>
+<!-- .LP -->
+To request that a top-level window be iconified, use
+<function>XIconifyWindow</function>.
+<indexterm significance="preferred"><primary>XIconifyWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xiconifywindow'>
+<funcprototype>
+ <funcdef>Status <function>XIconifyWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>int<parameter> screen_number</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen_number</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the appropriate screen number on the host server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XIconifyWindow</function>
+function sends a <property>WM_CHANGE_STATE</property>
+<symbol>ClientMessage</symbol>
+event with a format of 32 and a first data element of
+<symbol>IconicState</symbol>
+(as described in section 4.1.4 of the
+<emphasis remap='I'>Inter-Client Communication Conventions Manual</emphasis>)
+and a window of w
+to the root window of the specified screen
+with an event mask set to
+<symbol>SubstructureNotifyMask</symbol> |
+<symbol>SubstructureRedirectMask</symbol>.
+Window managers may elect to receive this message and
+if the window is in its normal state,
+may treat it as a request to change the window's state from normal to iconic.
+If the <property>WM_CHANGE_STATE</property> property cannot be interned,
+<function>XIconifyWindow</function>
+does not send a message and returns a zero status.
+It returns a nonzero status if the client message is sent successfully;
+otherwise, it returns a zero status.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To request that a top-level window be withdrawn, use
+<function>XWithdrawWindow</function>.
+<indexterm significance="preferred"><primary>XWithdrawWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xwithdrawwindow'>
+<funcprototype>
+ <funcdef>Status <function>XWithdrawWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>int<parameter> screen_number</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen_number</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the appropriate screen number on the host server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XWithdrawWindow</function>
+function unmaps the specified window
+and sends a synthetic
+<symbol>UnmapNotify</symbol>
+event to the root window of the specified screen.
+Window managers may elect to receive this message
+and may treat it as a request to change the window's state to withdrawn.
+When a window is in the withdrawn state,
+neither its normal nor its iconic representations is visible.
+It returns a nonzero status if the
+<symbol>UnmapNotify</symbol>
+event is successfully sent;
+otherwise, it returns a zero status.
+</para>
+<para>
+<!-- .LP -->
+<function>XWithdrawWindow</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To request that a top-level window be reconfigured, use
+<function>XReconfigureWMWindow</function>.
+<indexterm significance="preferred"><primary>XReconfigureWMWindow</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xreconfigurewmwindow'>
+<funcprototype>
+ <funcdef>Status <function>XReconfigureWMWindow</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>int<parameter> screen_number</parameter></paramdef>
+ <paramdef>unsignedint<parameter> value_mask</parameter></paramdef>
+ <paramdef>XWindowChanges<parameter> *values</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen_number</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the appropriate screen number on the host server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies which values are to be set using information in
+the values structure.
+This mask is the bitwise inclusive OR of the valid configure window values bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>values</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XWindowChanges</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XReconfigureWMWindow</function>
+function issues a
+<systemitem>ConfigureWindow</systemitem>
+request on the specified top-level window.
+If the stacking mode is changed and the request fails with a
+<errorname>BadMatch</errorname>
+error,
+the error is trapped by Xlib and a synthetic
+<systemitem class="event">ConfigureRequestEvent</systemitem>
+containing the same configuration parameters is sent to the root
+of the specified window.
+Window managers may elect to receive this event
+and treat it as a request to reconfigure the indicated window.
+It returns a nonzero status if the request or event is successfully sent;
+otherwise, it returns a zero status.
+</para>
+<para>
+<!-- .LP -->
+<function>XReconfigureWMWindow</function>
+can generate
+<errorname>BadValue</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Converting_String_Lists">
+<title>Converting String Lists</title>
+<!-- .XS -->
+<!-- (SN Converting String Lists -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Many of the text properties allow a variety of types and formats.
+Because the data stored in these properties are not
+simple null-terminated strings, an
+<structname>XTextProperty</structname>
+structure is used to describe the encoding, type, and length of the text
+as well as its value.
+The
+<structname>XTextProperty</structname>
+structure contains:
+<indexterm significance="preferred"><primary>XTextProperty</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ unsigned char *value; /* property data */
+ Atom encoding; /* type of property */
+ int format; /* 8, 16, or 32 */
+ unsigned long nitems; /* number of items in value */
+} XTextProperty;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Xlib provides functions to convert localized text to or from encodings
+that support the inter-client communication conventions for text.
+In addition, functions are provided for converting between lists of pointers
+to character strings and text properties in the STRING encoding.
+</para>
+<para>
+<!-- .LP -->
+The functions for localized text return a signed integer error status
+that encodes
+<symbol>Success</symbol>
+as zero, specific error conditions as negative numbers, and partial conversion
+as a count of unconvertible characters.
+</para>
+
+<literallayout class="monospaced">
+
+#define #XNoMemory -1
+#define #XLocaleNotSupported -2
+#define #XConverterNotFound -3
+
+typedef enum {
+ XStringStyle, /* STRING */
+ XCompoundTextStyle, /* COMPOUND_TEXT */
+ XTextStyle, /* text in owner's encoding (current locale) */
+ XStdICCTextStyle /* STRING, else COMPOUND_TEXT */
+} XICCEncodingStyle;
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To convert a list of text strings to an
+<structname>XTextProperty</structname>
+structure, use
+<function>XmbTextListToTextProperty</function>
+or
+<function>XwcTextListToTextProperty</function>.
+<indexterm significance="preferred"><primary>XmbTextListToTextProperty</primary></indexterm>
+<indexterm significance="preferred"><primary>XwcTextListToTextProperty</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmbtextlisttotextproperty'>
+<funcprototype>
+ <funcdef>int <function>XmbTextListToTextProperty</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> **list</parameter></paramdef>
+ <paramdef>int<parameter> count</parameter></paramdef>
+ <paramdef>XICCEncodingStyle<parameter> style</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<funcsynopsis id='xwctextlisttotextproperty'>
+<funcprototype>
+ <funcdef>int <function>XwcTextListToTextProperty</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>wchar_t<parameter> **list</parameter></paramdef>
+ <paramdef>int<parameter> count</parameter></paramdef>
+ <paramdef>XICCEncodingStyle<parameter> style</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a list of null-terminated character strings.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of strings specified.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>style</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the manner in which the property is encoded.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>text_prop_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the
+<structname>XTextProperty</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XmbTextListToTextProperty</function>
+and
+<function>XwcTextListToTextProperty</function>
+functions set the specified
+<structname>XTextProperty</structname>
+value to a set of null-separated elements representing the concatenation
+of the specified list of null-terminated text strings.
+A final terminating null is stored at the end of the value field
+of text_prop_return but is not included in the nitems member.
+</para>
+<para>
+<!-- .LP -->
+The functions set the encoding field of text_prop_return to an
+<type>Atom</type>
+for the specified display
+naming the encoding determined by the specified style
+and convert the specified text list to this encoding for storage in
+the text_prop_return value field.
+If the style
+<constant>XStringStyle</constant>
+or
+<constant>XCompoundTextStyle</constant>
+is specified,
+this encoding is ``STRING'' or ``COMPOUND_TEXT'', respectively.
+If the style
+<constant>XTextStyle</constant>
+is specified,
+this encoding is the encoding of the current locale.
+If the style
+<constant>XStdICCTextStyle</constant>
+is specified,
+this encoding is ``STRING'' if the text is fully convertible to STRING,
+else ``COMPOUND_TEXT''.
+</para>
+<para>
+<!-- .LP -->
+If insufficient memory is available for the new value string,
+the functions return
+<symbol>XNoMemory</symbol>.
+If the current locale is not supported,
+the functions return
+<symbol>XLocaleNotSupported</symbol>.
+In both of these error cases,
+the functions do not set text_prop_return.
+</para>
+<para>
+<!-- .LP -->
+To determine if the functions are guaranteed not to return
+<symbol>XLocaleNotSupported</symbol>,
+use
+<function>XSupportsLocale</function>.
+</para>
+<para>
+<!-- .LP -->
+If the supplied text is not fully convertible to the specified encoding,
+the functions return the number of unconvertible characters.
+Each unconvertible character is converted to an implementation-defined and
+encoding-specific default string.
+Otherwise, the functions return
+<symbol>Success</symbol>.
+Note that full convertibility to all styles except
+<constant>XStringStyle</constant>
+is guaranteed.
+</para>
+<para>
+<!-- .LP -->
+To free the storage for the value field, use
+<function>XFree</function>.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain a list of text strings from an
+<structname>XTextProperty</structname>
+structure, use
+<function>XmbTextPropertyToTextList</function>
+or
+<function>XwcTextPropertyToTextList</function>.
+<indexterm significance="preferred"><primary>XmbTextPropertyToTextList</primary></indexterm>
+<indexterm significance="preferred"><primary>XwcTextPropertyToTextList</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmbtextpropertytotextlist'>
+<funcprototype>
+ <funcdef>int <function>XmbTextPropertyToTextList</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
+ <paramdef>char<parameter> ***list_return</parameter></paramdef>
+ <paramdef>int<parameter> *count_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<funcsynopsis id='xwctextpropertytotextlist'>
+<funcprototype>
+ <funcdef>int <function>XwcTextPropertyToTextList</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
+ <paramdef>wchar_t<parameter> ***list_return</parameter></paramdef>
+ <paramdef>int<parameter> *count_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>text_prop</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XTextProperty</structname>
+structure to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns a list of null-terminated character strings.
+<!-- .ds Cn strings -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of (Cn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XmbTextPropertyToTextList</function>
+and
+<function>XwcTextPropertyToTextList</function>
+functions return a list of text strings in the current locale representing the
+null-separated elements of the specified
+<structname>XTextProperty</structname>
+structure.
+The data in text_prop must be format 8.
+</para>
+<para>
+<!-- .LP -->
+Multiple elements of the property (for example, the strings in a disjoint
+text selection) are separated by a null byte.
+The contents of the property are not required to be null-terminated;
+any terminating null should not be included in text_prop.nitems.
+</para>
+<para>
+<!-- .LP -->
+If insufficient memory is available for the list and its elements,
+<function>XmbTextPropertyToTextList</function>
+and
+<function>XwcTextPropertyToTextList</function>
+return
+<symbol>XNoMemory</symbol>.
+If the current locale is not supported,
+the functions return
+<symbol>XLocaleNotSupported</symbol>.
+Otherwise, if the encoding field of text_prop is not convertible
+to the encoding of the current locale,
+the functions return
+<symbol>XConverterNotFound</symbol>.
+For supported locales,
+existence of a converter from COMPOUND_TEXT, STRING
+or the encoding of the current locale is guaranteed if
+<function>XSupportsLocale</function>
+returns
+<symbol>True</symbol>
+for the current locale (but the actual text
+may contain unconvertible characters).
+Conversion of other encodings is implementation-dependent.
+In all of these error cases,
+the functions do not set any return values.
+</para>
+<para>
+<!-- .LP -->
+Otherwise,
+<function>XmbTextPropertyToTextList</function>
+and
+<function>XwcTextPropertyToTextList</function>
+return the list of null-terminated text strings to list_return
+and the number of text strings to count_return.
+</para>
+<para>
+<!-- .LP -->
+If the value field of text_prop is not fully convertible to the encoding of
+the current locale,
+the functions return the number of unconvertible characters.
+Each unconvertible character is converted to a string in the
+current locale that is specific to the current locale.
+To obtain the value of this string,
+use
+<function>XDefaultString</function>.
+Otherwise,
+<function>XmbTextPropertyToTextList</function>
+and
+<function>XwcTextPropertyToTextList</function>
+return
+<symbol>Success</symbol>.
+</para>
+<para>
+<!-- .LP -->
+To free the storage for the list and its contents returned by
+<function>XmbTextPropertyToTextList</function>,
+use
+<function>XFreeStringList</function>.
+To free the storage for the list and its contents returned by
+<function>XwcTextPropertyToTextList</function>,
+use
+<function>XwcFreeStringList</function>.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To free the in-memory data associated with the specified
+wide character string list, use
+<function>XwcFreeStringList</function>.
+<indexterm significance="preferred"><primary>XwcFreeStringList</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xwcfreestringlist'>
+<funcprototype>
+ <funcdef>void <function>XwcFreeStringList</function></funcdef>
+ <paramdef>wchar_t<parameter> **list</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the list of strings to be freed.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XwcFreeStringList</function>
+function frees memory allocated by
+<function>XwcTextPropertyToTextList</function>.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the default string for text conversion in the current locale,
+use</para>
+
+<para>char *XDefaultString()</para>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDefaultString</function>
+function returns the default string used by Xlib for text conversion
+(for example, in
+<function>XmbTextPropertyToTextList</function>).
+The default string is the string in the current locale that is output
+when an unconvertible character is found during text conversion.
+If the string returned by
+<function>XDefaultString</function>
+is the empty string (""),
+no character is output in the converted text.
+<function>XDefaultString</function>
+does not return NULL.
+</para>
+<para>
+<!-- .LP -->
+The string returned by
+<function>XDefaultString</function>
+is independent of the default string for text drawing;
+see
+<function>XCreateFontSet</function>
+to obtain the default string for an
+<type>XFontSet</type>.
+</para>
+<para>
+<!-- .LP -->
+The behavior when an invalid codepoint is supplied to any Xlib function is
+undefined.
+</para>
+<para>
+<!-- .LP -->
+The returned string is null-terminated.
+It is owned by Xlib and should not be modified or freed by the client.
+It may be freed after the current locale is changed.
+Until freed, it will not be modified by Xlib.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set the specified list of strings in the STRING encoding to a
+<structname>XTextProperty</structname>
+structure, use
+<function>XStringListToTextProperty</function>.
+<indexterm significance="preferred"><primary>XStringListToTextProperty</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xstringlisttotextproperty'>
+<funcprototype>
+ <funcdef>Status <function>XStringListToTextProperty</function></funcdef>
+ <paramdef>char<parameter> **list</parameter></paramdef>
+ <paramdef>int<parameter> count</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a list of null-terminated character strings.
+<!-- .ds Cn strings -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of (Cn.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>text_prop_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the
+<structname>XTextProperty</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XStringListToTextProperty</function>
+function sets the specified
+<structname>XTextProperty</structname>
+to be of type STRING (format 8) with a value representing the
+concatenation of the specified list of null-separated character strings.
+An extra null byte (which is not included in the nitems member)
+is stored at the end of the value field of text_prop_return.
+The strings are assumed (without verification) to be in the STRING encoding.
+If insufficient memory is available for the new value string,
+<function>XStringListToTextProperty</function>
+does not set any fields in the
+<structname>XTextProperty</structname>
+structure and returns a zero status.
+Otherwise, it returns a nonzero status.
+To free the storage for the value field, use
+<function>XFree</function>.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain a list of strings from a specified
+<structname>XTextProperty</structname>
+structure in the STRING encoding, use
+<function>XTextPropertyToStringList</function>.
+<indexterm significance="preferred"><primary>XTextPropertyToStringList</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xtextpropertytostringlist'>
+<funcprototype>
+ <funcdef>Status <function>XTextPropertyToStringList</function></funcdef>
+ <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
+ <paramdef>char<parameter> ***list_return</parameter></paramdef>
+ <paramdef>int<parameter> *count_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>text_prop</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XTextProperty</structname>
+structure to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns a list of null-terminated character strings.
+<!-- .ds Cn strings -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of (Cn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XTextPropertyToStringList</function>
+function returns a list of strings representing the null-separated elements
+of the specified
+<structname>XTextProperty</structname>
+structure.
+The data in text_prop must be of type STRING and format 8.
+Multiple elements of the property
+(for example, the strings in a disjoint text selection)
+are separated by NULL (encoding 0).
+The contents of the property are not null-terminated.
+If insufficient memory is available for the list and its elements,
+<function>XTextPropertyToStringList</function>
+sets no return values and returns a zero status.
+Otherwise, it returns a nonzero status.
+To free the storage for the list and its contents, use
+<function>XFreeStringList</function>.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To free the in-memory data associated with the specified string list, use
+<function>XFreeStringList</function>.
+<indexterm significance="preferred"><primary>XFreeStringList</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfreestringlist'>
+<funcprototype>
+ <funcdef>void <function>XFreeStringList</function></funcdef>
+ <paramdef>char<parameter> **list</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the list of strings to be freed.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFreeStringList</function>
+function releases memory allocated by
+<function>XmbTextPropertyToTextList</function>
+and
+<function>XTextPropertyToStringList</function>
+and the missing charset list allocated by
+<function>XCreateFontSet</function>.
+</para>
+</sect2>
+<sect2 id="Setting_and_Reading_Text_Properties">
+<title>Setting and Reading Text Properties</title>
+<!-- .XS -->
+<!-- (SN Setting and Reading Text Properties -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides two functions that you can use to set and read
+the text properties for a given window.
+You can use these functions to set and read those properties of type TEXT
+(<property>WM_NAME</property>, <property>WM_ICON_NAME</property>, <property>WM_COMMAND</property>, and <property>WM_CLIENT_MACHINE</property>).
+In addition,
+Xlib provides separate convenience functions that you can use to set each
+of these properties.
+For further information about these convenience functions,
+see sections 14.1.4, 14.1.5, 14.2.1, and 14.2.2, respectively.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set one of a window's text properties, use
+<function>XSetTextProperty</function>.
+<indexterm significance="preferred"><primary>XSetTextProperty</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsettextproperty'>
+<funcprototype>
+ <funcdef>void <function>XSetTextProperty</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
+ <paramdef>Atom<parameter> property</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>text_prop</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XTextProperty</structname>
+structure to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>property</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the property name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetTextProperty</function>
+function replaces the existing specified property for the named window
+with the data, type, format, and number of items determined
+by the value field, the encoding field, the format field,
+and the nitems field, respectively, of the specified
+<structname>XTextProperty</structname>
+structure.
+If the property does not already exist,
+<function>XSetTextProperty</function>
+sets it for the specified window.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetTextProperty</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadAtom</errorname>,
+<errorname>BadValue</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To read one of a window's text properties, use
+<function>XGetTextProperty</function>.
+<indexterm significance="preferred"><primary>XGetTextProperty</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgettextproperty'>
+<funcprototype>
+ <funcdef>Status <function>XGetTextProperty</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
+ <paramdef>Atom<parameter> property</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>text_prop_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the
+<structname>XTextProperty</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>property</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the property name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetTextProperty</function>
+function reads the specified property from the window
+and stores the data in the returned
+<structname>XTextProperty</structname>
+structure.
+It stores the data in the value field,
+the type of the data in the encoding field,
+the format of the data in the format field,
+and the number of items of data in the nitems field.
+An extra byte containing null (which is not included in the nitems member)
+is stored at the end of the value field of text_prop_return.
+The particular interpretation of the property's encoding
+and data as text is left to the calling application.
+If the specified property does not exist on the window,
+<function>XGetTextProperty</function>
+sets the value field to NULL,
+the encoding field to
+<symbol>None</symbol>,
+the format field to zero,
+and the nitems field to zero.
+</para>
+<para>
+<!-- .LP -->
+If it was able to read and store the data in the
+<structname>XTextProperty</structname>
+structure,
+<function>XGetTextProperty</function>
+returns a nonzero status;
+otherwise, it returns a zero status.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetTextProperty</function>
+can generate
+<errorname>BadAtom</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Setting_and_Reading_the_WM_NAME_Property">
+<title>Setting and Reading the WM_NAME Property</title>
+<!-- .XS -->
+<!-- (SN Setting and Reading the WM_NAME Property -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides convenience functions that you can use to set and read
+the <property>WM_NAME</property> property for a given window.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set a window's <property>WM_NAME</property> property with the supplied convenience function, use
+<function>XSetWMName</function>.
+<indexterm significance="preferred"><primary>XSetWMName</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwmname'>
+<funcprototype>
+ <funcdef>void <function>XSetWMName</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>text_prop</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XTextProperty</structname>
+structure to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWMName</function>
+convenience function calls
+<function>XSetTextProperty</function>
+to set the <property>WM_NAME</property> property.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To read a window's <property>WM_NAME</property> property with the supplied convenience function, use
+<function>XGetWMName</function>.
+<indexterm significance="preferred"><primary>XGetWMName</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetwmname'>
+<funcprototype>
+ <funcdef>Status <function>XGetWMName</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>text_prop_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the
+<structname>XTextProperty</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetWMName</function>
+convenience function calls
+<function>XGetTextProperty</function>
+to obtain the <property>WM_NAME</property> property.
+It returns a nonzero status on success;
+otherwise, it returns a zero status.
+</para>
+<para>
+<!-- .LP -->
+The following two functions have been superseded by
+<function>XSetWMName</function>
+and
+<function>XGetWMName</function>,
+respectively.
+You can use these additional convenience functions
+for window names that are encoded as STRING properties.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To assign a name to a window, use
+<function>XStoreName</function>.
+<indexterm><primary>Window</primary><secondary>name</secondary></indexterm>
+<indexterm significance="preferred"><primary>XStoreName</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xstorename'>
+<funcprototype>
+ <funcdef><function>XStoreName</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>char<parameter> *window_name</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>window_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window name,
+which should be a null-terminated string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XStoreName</function>
+function assigns the name passed to window_name to the specified window.
+A window manager can display the window name in some prominent
+place, such as the title bar, to allow users to identify windows easily.
+Some window managers may display a window's name in the window's icon,
+although they are encouraged to use the window's icon name
+if one is provided by the application.
+If the string is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+<function>XStoreName</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To get the name of a window, use
+<function>XFetchName</function>.
+<indexterm significance="preferred"><primary>XFetchName</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfetchname'>
+<funcprototype>
+ <funcdef>Status <function>XFetchName</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>char<parameter> **window_name_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>window_name_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the window name, which is a null-terminated string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFetchName</function>
+function returns the name of the specified window.
+If it succeeds,
+it returns a nonzero status;
+otherwise, no name has been set for the window,
+and it returns zero.
+If the <property>WM_NAME</property> property has not been set for this window,
+<function>XFetchName</function>
+sets window_name_return to NULL.
+If the data returned by the server is in the Latin Portable Character Encoding,
+then the returned string is in the Host Portable Character Encoding.
+Otherwise, the result is implementation-dependent.
+When finished with it, a client must free
+the window name string using
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XFetchName</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect2>
+<sect2 id="Setting_and_Reading_the_WM_ICON_NAME_Property">
+<title>Setting and Reading the WM_ICON_NAME Property</title>
+<!-- .XS -->
+<!-- (SN Setting and Reading the WM_ICON_NAME Property -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides convenience functions that you can use to set and read
+the <property>WM_ICON_NAME</property> property for a given window.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set a window's <property>WM_ICON_NAME</property> property,
+use
+<function>XSetWMIconName</function>.
+<indexterm significance="preferred"><primary>XSetWMIconName</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwmiconname'>
+<funcprototype>
+ <funcdef>void <function>XSetWMIconName</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>text_prop</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XTextProperty</structname>
+structure to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWMIconName</function>
+convenience function calls
+<function>XSetTextProperty</function>
+to set the <property>WM_ICON_NAME</property> property.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To read a window's <property>WM_ICON_NAME</property> property,
+use
+<function>XGetWMIconName</function>.
+<indexterm significance="preferred"><primary>XGetWMIconName</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetwmiconname'>
+<funcprototype>
+ <funcdef>Status <function>XGetWMIconName</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>text_prop_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the
+<structname>XTextProperty</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetWMIconName</function>
+convenience function calls
+<function>XGetTextProperty</function>
+to obtain the <property>WM_ICON_NAME</property> property.
+It returns a nonzero status on success;
+otherwise, it returns a zero status.
+</para>
+<para>
+<!-- .LP -->
+The next two functions have been superseded by
+<function>XSetWMIconName</function>
+and
+<function>XGetWMIconName</function>,
+respectively.
+You can use these additional convenience functions
+for window names that are encoded as STRING properties.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the name to be displayed in a window's icon, use
+<function>XSetIconName</function>.
+<indexterm><primary>Window</primary><secondary>icon name</secondary></indexterm>
+<indexterm significance="preferred"><primary>XSetIconName</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xseticonname'>
+<funcprototype>
+ <funcdef><function>XSetIconName</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>char<parameter> *icon_name</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>icon_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the icon name,
+which should be a null-terminated string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If the string is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+<function>XSetIconName</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To get the name a window wants displayed in its icon, use
+<function>XGetIconName</function>.
+<indexterm significance="preferred"><primary>XGetIconName</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgeticonname'>
+<funcprototype>
+ <funcdef>Status <function>XGetIconName</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>char<parameter> **icon_name_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>icon_name_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the window's icon name,
+which is a null-terminated string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetIconName</function>
+function returns the name to be displayed in the specified window's icon.
+If it succeeds, it returns a nonzero status; otherwise,
+if no icon name has been set for the window,
+it returns zero.
+If you never assigned a name to the window,
+<function>XGetIconName</function>
+sets icon_name_return to NULL.
+If the data returned by the server is in the Latin Portable Character Encoding,
+then the returned string is in the Host Portable Character Encoding.
+Otherwise, the result is implementation-dependent.
+When finished with it, a client must free
+the icon name string using
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetIconName</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect2>
+<sect2 id="Setting_and_Reading_the_WM_HINTS_Property">
+<title>Setting and Reading the WM_HINTS Property</title>
+<!-- .XS -->
+<!-- (SN Setting and Reading the WM_HINTS Property -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set and read
+the <property>WM_HINTS</property> property for a given window.
+These functions use the flags and the
+<structname>XWMHints</structname>
+structure, as defined in the
+<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
+<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+header file.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To allocate an
+<structname>XWMHints</structname>
+structure, use
+<function>XAllocWMHints</function>.
+</para>
+
+<para>
+ XWMHints *XAllocWMHints()
+</para>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAllocWMHints</function>
+function allocates and returns a pointer to an
+<structname>XWMHints</structname>
+structure.
+Note that all fields in the
+<structname>XWMHints</structname>
+structure are initially set to zero.
+If insufficient memory is available,
+<function>XAllocWMHints</function>
+returns NULL.
+To free the memory allocated to this structure,
+use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XWMHints</structname>
+structure contains:
+</para>
+
+<literallayout class="monospaced">
+/* Window manager hints mask bits */
+
+#define InputHint (1L&lt;&lt;0)
+#define StateHint (1L&lt;&lt;1)
+#define IconPixmapHint (1L&lt;&lt;2)
+#define IconWindowHint (1L&lt;&lt;3)
+#define IconPositionHint (1L&lt;&lt;4)
+#define IconMaskHint (1L&lt;&lt;5)
+#define WindowGroupHint (1L&lt;&lt;6)
+#define UrgencyHint (1L&lt;&lt;8)
+#define AllHints (InputHint|StateHint|IconPixmapHint|
+ IconWIndowHint|IconPositionHint|
+ IconMaskHint|WindowGroupHint)
+
+
+/* Values */
+
+typedef struct {
+ long flags; /* marks which fields in this structure are defined */
+ Bool input; /* does this application rely on the window manager to
+ get keyboard input? */
+ int initial_state; /* see below */
+ Pixmap icon_pixmap; /* pixmap to be used as icon */
+ Window icon_window; /* window to be used as icon */
+ int icon_x, icon_y; /* initial position of icon */
+ Pixmap icon_mask; /* pixmap to be used as mask for icon_pixmap */
+ XID window_group; /* id of related window group */
+ /* this structure may be extended in the future */
+} XWMHints;
+</literallayout>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The input member is used to communicate to the window manager the input focus
+model used by the application.
+Applications that expect input but never explicitly set focus to any
+of their subwindows (that is, use the push model of focus management),
+such as X Version 10 style applications that use real-estate
+driven focus, should set this member to
+<symbol>True</symbol>.
+Similarly, applications
+that set input focus to their subwindows only when it is given to their
+top-level window by a window manager should also set this member to
+<symbol>True</symbol>.
+Applications that manage their own input focus by explicitly setting
+focus to one of their subwindows whenever they want keyboard input
+(that is, use the pull model of focus management) should set this member to
+<symbol>False</symbol>.
+Applications that never expect any keyboard input also should set this member
+to
+<symbol>False</symbol>.
+</para>
+<para>
+<!-- .LP -->
+Pull model window managers should make it possible for push model
+applications to get input by setting input focus to the top-level windows of
+applications whose input member is
+<symbol>True</symbol>.
+Push model window managers should
+make sure that pull model applications do not break them
+by resetting input focus to
+<symbol>PointerRoot</symbol>
+when it is appropriate (for example, whenever an application whose
+input member is
+<symbol>False</symbol>
+sets input focus to one of its subwindows).
+</para>
+<para>
+<!-- .LP -->
+The definitions for the initial_state flag are:
+</para>
+
+<literallayout class="monospaced">
+#define WithdrawnState 0
+#define NormalState 1 /* most applications start this way */
+#define IconicState 2 /* application wants to start as an icon */
+
+</literallayout>
+<para>
+The icon_mask specifies which pixels of the icon_pixmap should be used as the
+icon.
+This allows for nonrectangular icons.
+Both icon_pixmap and icon_mask must be bitmaps.
+The icon_window lets an application provide a window for use as an icon
+for window managers that support such use.
+The window_group lets you specify that this window belongs to a group
+of other windows.
+For example, if a single application manipulates multiple
+top-level windows, this allows you to provide enough
+information that a window manager can iconify all of the windows
+rather than just the one window.
+</para>
+<para>
+<!-- .LP -->
+The
+<symbol>UrgencyHint</symbol>
+flag, if set in the flags field, indicates that the client deems the window
+contents to be urgent, requiring the timely response of the user. The
+window manager will make some effort to draw the user's attention to this
+window while this flag is set. The client must provide some means by which the
+user can cause the urgency flag to be cleared (either mitigating
+the condition that made the window urgent or merely shutting off the alarm)
+or the window to be withdrawn.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set a window's <property>WM_HINTS</property> property, use
+<function>XSetWMHints</function>.
+<indexterm significance="preferred"><primary>XSetWMHints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwmhints'>
+<funcprototype>
+ <funcdef><function>XSetWMHints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XWMHints<parameter> *wmhints</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>wmhints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XWMHints</structname>
+structure to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWMHints</function>
+function sets the window manager hints that include icon information and location,
+the initial state of the window, and whether the application relies on the
+window manager to get keyboard input.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetWMHints</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To read a window's <property>WM_HINTS</property> property, use
+<function>XGetWMHints</function>.
+<indexterm significance="preferred"><primary>XGetWMHints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetwmhints'>
+<funcprototype>
+ <funcdef>XWMHints *<function>XGetWMHints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetWMHints</function>
+function reads the window manager hints and
+returns NULL if no <property>WM_HINTS</property> property was set on the window
+or returns a pointer to an
+<structname>XWMHints</structname>
+structure if it succeeds.
+When finished with the data,
+free the space used for it by calling
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetWMHints</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect2>
+<sect2 id="Setting_and_Reading_the_WM_NORMAL_HINTS_Property">
+<title>Setting and Reading the WM_NORMAL_HINTS Property</title>
+<!-- .XS -->
+<!-- (SN Setting and Reading the WM_NORMAL_HINTS Property -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set or read
+the <property>WM_NORMAL_HINTS</property> property for a given window.
+The functions use the flags and the
+<structname>XSizeHints</structname>
+structure, as defined in the
+<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
+<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+header file.
+</para>
+<para>
+<!-- .LP -->
+The size of the
+<structname>XSizeHints</structname>
+structure may grow in future releases, as new components are
+added to support new <acronym>ICCCM</acronym> features.
+Passing statically allocated instances of this structure into
+Xlib may result in memory corruption when running against a
+future release of the library.
+As such, it is recommended that only dynamically allocated
+instances of the structure be used.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To allocate an
+<structname>XSizeHints</structname>
+structure, use
+<function>XAllocSizeHints</function>.
+</para>
+
+<para>
+XSizeHints *XAllocSizeHints()
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAllocSizeHints</function>
+function allocates and returns a pointer to an
+<structname>XSizeHints</structname>
+structure.
+Note that all fields in the
+<structname>XSizeHints</structname>
+structure are initially set to zero.
+If insufficient memory is available,
+<function>XAllocSizeHints</function>
+returns NULL.
+To free the memory allocated to this structure,
+use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XSizeHints</structname>
+structure contains:
+</para>
+
+
+<literallayout class="monospaced">
+/* Size hints mask bits */
+
+#define USPosition (1L&lt;&lt;0) /* user specified x,y */
+#define USSize (1L&lt;&lt;1) /* user specified width,height */
+#define PPosition (1L&lt;&lt;2) /* program specified posistion */
+#define PSize (1L&lt;&lt;3) /* program specified size */
+#define PMinSize (1L&lt;&lt;4) /* program specified minimum size */
+#define PMaxSize (1L&lt;&lt;5) /* program specified maximum size */
+#define PResizeInc (1L&lt;&lt;5) /* program specified resize increments */
+#define PAspect (1L&lt;&lt;6) /* program specified min and max aspect ratios */
+#define PBaseSize (1L&lt;&lt;8)
+#define PWinGravity (1L&lt;&lt;9)
+#define PAllHints (PPosition|Psize|
+ PMinSize|PMaxSize|
+ PResizeInc|PAspect)
+
+
+/* Values */
+
+typedef struct {
+ long flags; /* marks which fields in this structure are defined */
+ int x, y; /* Obsolete */
+ int width, height; /* Obsolete */
+ int min_width, min_height;
+ int max_width, max_height;
+ int width_inc, height_inc;
+ struct {
+ int x; /* numerator */
+ int y; /* denominator */
+ } min_aspect, max_aspect;
+ int base_width, base_height;
+ int win_gravity;
+ /* this structure may be extended in the future */
+} XSizeHints;
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The x, y, width, and height members are now obsolete
+and are left solely for compatibility reasons.
+The min_width and min_height members specify the
+minimum window size that still allows the application to be useful.
+The max_width and max_height members specify the maximum window size.
+The width_inc and height_inc members define an arithmetic progression of
+sizes (minimum to maximum) into which the window prefers to be resized.
+The min_aspect and max_aspect members are expressed
+as ratios of x and y,
+and they allow an application to specify the range of aspect
+ratios it prefers.
+The base_width and base_height members define the desired size of the window.
+The window manager will interpret the position of the window
+and its border width to position the point of the outer rectangle
+of the overall window specified by the win_gravity member.
+The outer rectangle of the window includes any borders or decorations
+supplied by the window manager.
+In other words,
+if the window manager decides to place the window where the client asked,
+the position on the parent window's border named by the win_gravity
+will be placed where the client window would have been placed
+in the absence of a window manager.
+</para>
+<para>
+<!-- .LP -->
+Note that use of the
+<symbol>PAllHints</symbol>
+macro is highly discouraged.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set a window's <property>WM_NORMAL_HINTS</property> property, use
+<function>XSetWMNormalHints</function>.
+<indexterm significance="preferred"><primary>XSetWMNormalHints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwmnormalhints'>
+<funcprototype>
+ <funcdef>void <function>XSetWMNormalHints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the size hints for the window in its normal state.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWMNormalHints</function>
+function replaces the size hints for the <property>WM_NORMAL_HINTS</property> property
+on the specified window.
+If the property does not already exist,
+<function>XSetWMNormalHints</function>
+sets the size hints for the <property>WM_NORMAL_HINTS</property> property on the specified window.
+The property is stored with a type of <property>WM_SIZE_HINTS</property> and a format of 32.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetWMNormalHints</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To read a window's <property>WM_NORMAL_HINTS</property> property, use
+<function>XGetWMNormalHints</function>.
+<indexterm significance="preferred"><primary>XGetWMNormalHints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetwmnormalhints'>
+<funcprototype>
+ <funcdef>Status <function>XGetWMNormalHints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *hints_return</parameter></paramdef>
+ <paramdef>long<parameter> *supplied_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hints_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the size hints for the window in its normal state.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>supplied_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the hints that were supplied by the user.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetWMNormalHints</function>
+function returns the size hints stored in the <property>WM_NORMAL_HINTS</property> property
+on the specified window.
+If the property is of type <property>WM_SIZE_HINTS</property>, is of format 32,
+and is long enough to contain either an old (pre-<acronym>ICCCM</acronym>)
+or new size hints structure,
+<function>XGetWMNormalHints</function>
+sets the various fields of the
+<structname>XSizeHints</structname>
+structure, sets the supplied_return argument to the list of fields
+that were supplied by the user (whether or not they contained defined values),
+and returns a nonzero status.
+Otherwise, it returns a zero status.
+</para>
+<para>
+<!-- .LP -->
+If
+<function>XGetWMNormalHints</function>
+returns successfully and a pre-<acronym>ICCCM</acronym> size hints property is read,
+the supplied_return argument will contain the following bits:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+(USPosition|USSize|PPosition|PSize|PMinSize|
+ PMaxSize|PResizeInc|PAspect)
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+If the property is large enough to contain the base size
+and window gravity fields as well,
+the supplied_return argument will also contain the following bits:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+PBaseSize|PWinGravity
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<function>XGetWMNormalHints</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set a window's <property>WM_SIZE_HINTS</property> property, use
+<function>XSetWMSizeHints</function>.
+<indexterm significance="preferred"><primary>XSetWMSizeHints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwmsizehints'>
+<funcprototype>
+ <funcdef>void <function>XSetWMSizeHints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
+ <paramdef>Atom<parameter> property</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XSizeHints</structname>
+structure to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>property</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the property name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWMSizeHints</function>
+function replaces the size hints for the specified property
+on the named window.
+If the specified property does not already exist,
+<function>XSetWMSizeHints</function>
+sets the size hints for the specified property
+on the named window.
+The property is stored with a type of <property>WM_SIZE_HINTS</property> and a format of 32.
+To set a window's normal size hints,
+you can use the
+<function>XSetWMNormalHints</function>
+function.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetWMSizeHints</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadAtom</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To read a window's <property>WM_SIZE_HINTS</property> property, use
+<function>XGetWMSizeHints</function>.
+<indexterm significance="preferred"><primary>XGetWMSizeHints</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetwmsizehints'>
+<funcprototype>
+ <funcdef>Status <function>XGetWMSizeHints</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *hints_return</parameter></paramdef>
+ <paramdef>long<parameter> *supplied_return</parameter></paramdef>
+ <paramdef>Atom<parameter> property</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hints_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the
+<structname>XSizeHints</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>supplied_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the hints that were supplied by the user.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>property</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the property name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetWMSizeHints</function>
+function returns the size hints stored in the specified property
+on the named window.
+If the property is of type <property>WM_SIZE_HINTS</property>, is of format 32,
+and is long enough to contain either an old (pre-<acronym>ICCCM</acronym>)
+or new size hints structure,
+<function>XGetWMSizeHints</function>
+sets the various fields of the
+<structname>XSizeHints</structname>
+structure, sets the supplied_return argument to the
+list of fields that were supplied by the user
+(whether or not they contained defined values),
+and returns a nonzero status.
+Otherwise, it returns a zero status.
+To get a window's normal size hints,
+you can use the
+<function>XGetWMNormalHints</function>
+function.
+</para>
+<para>
+<!-- .LP -->
+If
+<function>XGetWMSizeHints</function>
+returns successfully and a pre-<acronym>ICCCM</acronym> size hints property is read,
+the supplied_return argument will contain the following bits:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+(USPosition|USSize|PPosition|PSize|PMinSize|
+ PMaxSize|PResizeInc|PAspect)
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+If the property is large enough to contain the base size
+and window gravity fields as well,
+the supplied_return argument will also contain the following bits:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+PBaseSize|PWinGravity
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<function>XGetWMSizeHints</function>
+can generate
+<errorname>BadAtom</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect2>
+<sect2 id="Setting_and_Reading_the_WM_CLASS_Property">
+<title>Setting and Reading the WM_CLASS Property</title>
+<!-- .XS -->
+<!-- (SN Setting and Reading the WM_CLASS Property -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set and get
+the <property>WM_CLASS</property> property for a given window.
+These functions use the
+<structname>XClassHint</structname>
+structure, which is defined in the
+<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
+<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+header file.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To allocate an
+<structname>XClassHint</structname>
+structure, use
+<function>XAllocClassHint</function>.
+<indexterm significance="preferred"><primary>XAllocClassHint</primary></indexterm>
+<!-- .sM -->
+</para>
+<para>
+
+ XClassHint *XAllocClassHint()
+</para>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAllocClassHint</function>
+function allocates and returns a pointer to an
+<structname>XClassHint</structname>
+structure.
+Note that the pointer fields in the
+<structname>XClassHint</structname>
+structure are initially set to NULL.
+If insufficient memory is available,
+<function>XAllocClassHint</function>
+returns NULL.
+To free the memory allocated to this structure,
+use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XClassHint</structname>
+contains:
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<indexterm significance="preferred"><primary>XClassHint</primary></indexterm>
+<literallayout class="monospaced">
+<!-- .TA .5i -->
+<!-- .ta .5i -->
+typedef struct {
+ char *res_name;
+ char *res_class;
+} XClassHint;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The res_name member contains the application name,
+and the res_class member contains the application class.
+Note that the name set in this property may differ from the name set as <property>WM_NAME</property>.
+That is, <property>WM_NAME</property> specifies what should be displayed in the title bar and,
+therefore, can contain temporal information (for example, the name of
+a file currently in an editor's buffer).
+On the other hand,
+the name specified as part of <property>WM_CLASS</property> is the formal name of the application
+that should be used when retrieving the application's resources from the
+resource database.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set a window's <property>WM_CLASS</property> property, use
+<function>XSetClassHint</function>.
+<indexterm significance="preferred"><primary>XSetClassHint</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetclasshint'>
+<funcprototype>
+ <funcdef><function>XSetClassHint</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XClassHint<parameter> *class_hints</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>class_hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XClassHint</structname>
+structure that is to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetClassHint</function>
+function sets the class hint for the specified window.
+If the strings are not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetClassHint</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To read a window's <property>WM_CLASS</property> property, use
+<function>XGetClassHint</function>.
+<indexterm significance="preferred"><primary>XGetClassHint</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetclasshint'>
+<funcprototype>
+ <funcdef>Status <function>XGetClassHint</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XClassHint<parameter> *class_hints_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>class_hints_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the
+<structname>XClassHint</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetClassHint</function>
+function returns the class hint of the specified window to the members
+of the supplied structure.
+If the data returned by the server is in the Latin Portable Character Encoding,
+then the returned strings are in the Host Portable Character Encoding.
+Otherwise, the result is implementation-dependent.
+It returns a nonzero status on success;
+otherwise, it returns a zero status.
+To free res_name and res_class when finished with the strings,
+use
+<function>XFree</function>
+on each individually.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetClassHint</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect2>
+<sect2 id="Setting_and_Reading_the_WM_TRANSIENT_FOR_Property">
+<title>Setting and Reading the WM_TRANSIENT_FOR Property</title>
+<!-- .XS -->
+<!-- (SN Setting and Reading the WM_TRANSIENT_FOR Property -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set and read
+the <property>WM_TRANSIENT_FOR</property> property for a given window.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set a window's <property>WM_TRANSIENT_FOR</property> property, use
+<function>XSetTransientForHint</function>.
+<indexterm significance="preferred"><primary>XSetTransientForHint</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsettransientforhint'>
+<funcprototype>
+ <funcdef><function>XSetTransientForHint</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Window<parameter> prop_window</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>prop_window</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window that the <property>WM_TRANSIENT_FOR</property> property is to be set to.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetTransientForHint</function>
+function sets the <property>WM_TRANSIENT_FOR</property> property of the specified window to the
+specified prop_window.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetTransientForHint</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To read a window's <property>WM_TRANSIENT_FOR</property> property, use
+<function>XGetTransientForHint</function>.
+<indexterm significance="preferred"><primary>XGetTransientForHint</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgettransientforhint'>
+<funcprototype>
+ <funcdef>Status <function>XGetTransientForHint</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Window<parameter> *prop_window_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>prop_window_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the <property>WM_TRANSIENT_FOR</property> property of the specified window.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetTransientForHint</function>
+function returns the <property>WM_TRANSIENT_FOR</property> property for the specified window.
+It returns a nonzero status on success;
+otherwise, it returns a zero status.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetTransientForHint</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect2>
+<sect2 id="Setting_and_Reading_the_WM_PROTOCOLS_Property">
+<title>Setting and Reading the WM_PROTOCOLS Property</title>
+<!-- .XS -->
+<!-- (SN Setting and Reading the WM_PROTOCOLS Property -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set and read
+the <property>WM_PROTOCOLS</property> property for a given window.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set a window's <property>WM_PROTOCOLS</property> property, use
+<function>XSetWMProtocols</function>.
+<indexterm significance="preferred"><primary>XSetWMProtocols</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwmprotocols'>
+<funcprototype>
+ <funcdef>Status <function>XSetWMProtocols</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Atom<parameter> *protocols</parameter></paramdef>
+ <paramdef>int<parameter> count</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>protocols</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the list of protocols.
+<!-- .ds Cn protocols in the list -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of (Cn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWMProtocols</function>
+function replaces the <property>WM_PROTOCOLS</property> property on the specified window
+with the list of atoms specified by the protocols argument.
+If the property does not already exist,
+<function>XSetWMProtocols</function>
+sets the <property>WM_PROTOCOLS</property> property on the specified window
+to the list of atoms specified by the protocols argument.
+The property is stored with a type of ATOM and a format of 32.
+If it cannot intern the <property>WM_PROTOCOLS</property> atom,
+<function>XSetWMProtocols</function>
+returns a zero status.
+Otherwise, it returns a nonzero status.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetWMProtocols</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To read a window's <property>WM_PROTOCOLS</property> property, use
+<function>XGetWMProtocols</function>.
+<indexterm significance="preferred"><primary>XGetWMProtocols</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetwmprotocols'>
+<funcprototype>
+ <funcdef>Status <function>XGetWMProtocols</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Atom<parameter> **protocols_return</parameter></paramdef>
+ <paramdef>int<parameter> *count_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>protocols_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the list of protocols.
+<!-- .ds Cn protocols in the list -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of (Cn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetWMProtocols</function>
+function returns the list of atoms stored in the <property>WM_PROTOCOLS</property> property
+on the specified window.
+These atoms describe window manager protocols in which the owner
+of this window is willing to participate.
+If the property exists, is of type ATOM, is of format 32,
+and the atom <property>WM_PROTOCOLS</property> can be interned,
+<function>XGetWMProtocols</function>
+sets the protocols_return argument to a list of atoms,
+sets the count_return argument to the number of elements in the list,
+and returns a nonzero status.
+Otherwise, it sets neither of the return arguments
+and returns a zero status.
+To release the list of atoms, use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetWMProtocols</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect2>
+<sect2 id="Setting_and_Reading_the_WM_COLORMAP_WINDOWS_Property">
+<title>Setting and Reading the WM_COLORMAP_WINDOWS Property</title>
+<!-- .XS -->
+<!-- (SN Setting and Reading the WM_COLORMAP_WINDOWS Property -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set and read
+the <property>WM_COLORMAP_WINDOWS</property> property for a given window.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set a window's <property>WM_COLORMAP_WINDOWS</property> property, use
+<function>XSetWMColormapWindows</function>.
+<indexterm significance="preferred"><primary>XSetWMColormapWindows</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwmcolormapwindows'>
+<funcprototype>
+ <funcdef>Status <function>XSetWMColormapWindows</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Window<parameter> *colormap_windows</parameter></paramdef>
+ <paramdef>int<parameter> count</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap_windows</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the list of windows.
+<!-- .ds Cn windows in the list -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of (Cn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWMColormapWindows</function>
+function replaces the <property>WM_COLORMAP_WINDOWS</property> property on the specified
+window with the list of windows specified by the colormap_windows argument.
+If the property does not already exist,
+<function>XSetWMColormapWindows</function>
+sets the <property>WM_COLORMAP_WINDOWS</property> property on the specified
+window to the list of windows specified by the colormap_windows argument.
+The property is stored with a type of WINDOW and a format of 32.
+If it cannot intern the <property>WM_COLORMAP_WINDOWS</property> atom,
+<function>XSetWMColormapWindows</function>
+returns a zero status.
+Otherwise, it returns a nonzero status.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetWMColormapWindows</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To read a window's <property>WM_COLORMAP_WINDOWS</property> property, use
+<function>XGetWMColormapWindows</function>.
+<indexterm significance="preferred"><primary>XGetWMColormapWindows</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetwmcolormapwindows'>
+<funcprototype>
+ <funcdef>Status <function>XGetWMColormapWindows</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>Window<parameter> **colormap_windows_return</parameter></paramdef>
+ <paramdef>int<parameter> *count_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>colormap_windows_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the list of windows.
+<!-- .ds Cn windows in the list -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of (Cn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetWMColormapWindows</function>
+function returns the list of window identifiers stored
+in the <property>WM_COLORMAP_WINDOWS</property> property on the specified window.
+These identifiers indicate the colormaps that the window manager
+may need to install for this window.
+If the property exists, is of type WINDOW, is of format 32,
+and the atom <property>WM_COLORMAP_WINDOWS</property> can be interned,
+<function>XGetWMColormapWindows</function>
+sets the windows_return argument to a list of window identifiers,
+sets the count_return argument to the number of elements in the list,
+and returns a nonzero status.
+Otherwise, it sets neither of the return arguments
+and returns a zero status.
+To release the list of window identifiers, use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetWMColormapWindows</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect2>
+<sect2 id="Setting_and_Reading_the_WM_ICON_SIZE_Property">
+<title>Setting and Reading the WM_ICON_SIZE Property</title>
+<!-- .XS -->
+<!-- (SN Setting and Reading the WM_ICON_SIZE Property -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set and read
+the <property>WM_ICON_SIZE</property> property for a given window.
+These functions use the
+<structname>XIconSize</structname>
+<indexterm><primary>XIconSize</primary></indexterm>
+structure, which is defined in the
+<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
+<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+header file.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To allocate an
+<structname>XIconSize</structname>
+structure, use
+<function>XAllocIconSize</function>.
+</para>
+
+<para>
+ XIconSize *XAllocIconSize()
+</para>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAllocIconSize</function>
+function allocates and returns a pointer to an
+<structname>XIconSize</structname>
+structure.
+Note that all fields in the
+<structname>XIconSize</structname>
+structure are initially set to zero.
+If insufficient memory is available,
+<function>XAllocIconSize</function>
+returns NULL.
+To free the memory allocated to this structure,
+use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XIconSize</structname>
+structure contains:
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<indexterm significance="preferred"><primary>XIconSize</primary></indexterm>
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ int min_width, min_height;
+ int max_width, max_height;
+ int width_inc, height_inc;
+} XIconSize;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The width_inc and height_inc members define an arithmetic progression of
+sizes (minimum to maximum) that represent the supported icon sizes.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set a window's <property>WM_ICON_SIZE</property> property, use
+<function>XSetIconSizes</function>.
+<indexterm significance="preferred"><primary>XSetIconSizes</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xseticonsizes'>
+<funcprototype>
+ <funcdef><function>XSetIconSizes</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XIconSize<parameter> *size_list</parameter></paramdef>
+ <paramdef>int<parameter> count</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>size_list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the size list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of items in the size list.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetIconSizes</function>
+function is used only by window managers to set the supported icon sizes.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetIconSizes</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To read a window's <property>WM_ICON_SIZE</property> property, use
+<function>XGetIconSizes</function>.
+<indexterm significance="preferred"><primary>XGetIconSizes</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgeticonsizes'>
+<funcprototype>
+ <funcdef>Status <function>XGetIconSizes</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XIconSize<parameter> **size_list_return</parameter></paramdef>
+ <paramdef>int<parameter> *count_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>size_list_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the size list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of items in the size list.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetIconSizes</function>
+function returns zero if a window manager has not set icon sizes;
+otherwise, it returns nonzero.
+<function>XGetIconSizes</function>
+should be called by an application that
+wants to find out what icon sizes would be most appreciated by the
+window manager under which the application is running.
+The application
+should then use
+<function>XSetWMHints</function>
+to supply the window manager with an icon pixmap or window in one of the
+supported sizes.
+To free the data allocated in size_list_return, use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetIconSizes</function>
+can generate a
+<errorname>BadWindow</errorname>
+error.
+</para>
+</sect2>
+<sect2 id="Using_Window_Manager_Convenience_Functions">
+<title>Using Window Manager Convenience Functions</title>
+<!-- .XS -->
+<!-- (SN Using Window Manager Convenience Functions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<function>XmbSetWMProperties</function>
+function stores the standard set of window manager properties,
+with text properties in standard encodings
+for internationalized text communication.
+The standard window manager properties for a given window are
+<property>WM_NAME</property>, <property>WM_ICON_NAME</property>, <property>WM_HINTS</property>, <property>WM_NORMAL_HINTS</property>, <property>WM_CLASS</property>,
+<property>WM_COMMAND</property>, <property>WM_CLIENT_MACHINE</property>, and <property>WM_LOCALE_NAME</property>.
+<indexterm significance="preferred"><primary>XmbSetWMProperties</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmbsetwmproperties'>
+<funcprototype>
+ <funcdef>void <function>XmbSetWMProperties</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>char<parameter> *window_name</parameter></paramdef>
+ <paramdef>char<parameter> *icon_name</parameter></paramdef>
+ <paramdef>char<parameter> *argv[]</parameter></paramdef>
+ <paramdef>int<parameter> argc</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *normal_hints</parameter></paramdef>
+ <paramdef>XWMHints<parameter> *wm_hints</parameter></paramdef>
+ <paramdef>XClassHint<parameter> *class_hints</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>window_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window name,
+which should be a null-terminated string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>icon_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the icon name,
+which should be a null-terminated string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>argv</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the application's argument list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>argc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of arguments.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the size hints for the window in its normal state.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>wm_hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XWMHints</structname>
+structure to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>class_hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XClassHint</structname>
+structure to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XmbSetWMProperties</function>
+convenience function provides a simple programming interface
+for setting those essential window properties that are used
+for communicating with other clients
+(particularly window and session managers).
+</para>
+<para>
+<!-- .LP -->
+If the window_name argument is non-NULL,
+<function>XmbSetWMProperties</function>
+sets the <property>WM_NAME</property> property.
+If the icon_name argument is non-NULL,
+<function>XmbSetWMProperties</function>
+sets the <property>WM_ICON_NAME</property> property.
+The window_name and icon_name arguments are null-terminated strings
+in the encoding of the current locale.
+If the arguments can be fully converted to the STRING encoding,
+the properties are created with type ``STRING'';
+otherwise, the arguments are converted to Compound Text,
+and the properties are created with type ``COMPOUND_TEXT''.
+</para>
+<para>
+<!-- .LP -->
+If the normal_hints argument is non-NULL,
+<function>XmbSetWMProperties</function>
+calls
+<function>XSetWMNormalHints</function>,
+which sets the <property>WM_NORMAL_HINTS</property> property (see section 14.1.7).
+If the wm_hints argument is non-NULL,
+<function>XmbSetWMProperties</function>
+calls
+<function>XSetWMHints</function>,
+which sets the <property>WM_HINTS</property> property (see section 14.1.6).
+</para>
+<para>
+<!-- .LP -->
+If the argv argument is non-NULL,
+<function>XmbSetWMProperties</function>
+sets the <property>WM_COMMAND</property> property from argv and argc.
+An argc of zero indicates a zero-length command.
+</para>
+<para>
+<!-- .LP -->
+The hostname of the machine is stored using
+<function>XSetWMClientMachine</function>
+(see section 14.2.2).
+</para>
+<para>
+<!-- .LP -->
+If the class_hints argument is non-NULL,
+<function>XmbSetWMProperties</function>
+sets the <property>WM_CLASS</property> property.
+If the res_name member in the
+<structname>XClassHint</structname>
+structure is set to the NULL pointer and the RESOURCE_NAME
+environment variable is set,
+the value of the environment variable is substituted for res_name.
+If the res_name member is NULL,
+the environment variable is not set, and argv and argv[0] are set,
+then the value of argv[0], stripped of any directory prefixes,
+is substituted for res_name.
+</para>
+<para>
+<!-- .LP -->
+It is assumed that the supplied class_hints.res_name and argv,
+the RESOURCE_NAME environment variable, and the hostname of the machine
+are in the encoding of the locale announced for the LC_CTYPE category
+(on <acronym>POSIX</acronym>-compliant systems, the LC_CTYPE, else LANG environment variable).
+The corresponding <property>WM_CLASS</property>, <property>WM_COMMAND</property>, and <property>WM_CLIENT_MACHINE</property> properties
+are typed according to the local host locale announcer.
+No encoding conversion is performed prior to storage in the properties.
+</para>
+<para>
+<!-- .LP -->
+For clients that need to process the property text in a locale,
+<function>XmbSetWMProperties</function>
+sets the <property>WM_LOCALE_NAME</property> property to be the name of the current locale.
+The name is assumed to be in the Host Portable Character Encoding
+and is converted to STRING for storage in the property.
+</para>
+<para>
+<!-- .LP -->
+<function>XmbSetWMProperties</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set a window's standard window manager properties
+with strings in client-specified encodings, use
+<function>XSetWMProperties</function>.
+The standard window manager properties for a given window are
+<property>WM_NAME</property>, <property>WM_ICON_NAME</property>, <property>WM_HINTS</property>, <property>WM_NORMAL_HINTS</property>, <property>WM_CLASS</property>,
+<property>WM_COMMAND</property>, and <property>WM_CLIENT_MACHINE</property>.
+<indexterm significance="preferred"><primary>XSetWMProperties</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwmproperties'>
+<funcprototype>
+ <funcdef>void <function>XSetWMProperties</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *window_name</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *icon_name</parameter></paramdef>
+ <paramdef>char<parameter> **argv</parameter></paramdef>
+ <paramdef>int<parameter> argc</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *normal_hints</parameter></paramdef>
+ <paramdef>XWMHints<parameter> *wm_hints</parameter></paramdef>
+ <paramdef>XClassHint<parameter> *class_hints</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>window_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window name,
+which should be a null-terminated string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>icon_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the icon name,
+which should be a null-terminated string.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>argv</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the application's argument list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>argc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of arguments.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>normal_hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the size hints for the window in its normal state.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>wm_hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XWMHints</structname>
+structure to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>class_hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XClassHint</structname>
+structure to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWMProperties</function>
+convenience function provides a single programming interface
+for setting those essential window properties that are used
+for communicating with other clients (particularly window and session
+managers).
+</para>
+<para>
+<!-- .LP -->
+If the window_name argument is non-NULL,
+<function>XSetWMProperties</function>
+calls
+<function>XSetWMName</function>,
+which, in turn, sets the <property>WM_NAME</property> property (see section 14.1.4).
+If the icon_name argument is non-NULL,
+<function>XSetWMProperties</function>
+calls
+<function>XSetWMIconName</function>,
+which sets the <property>WM_ICON_NAME</property> property (see section 14.1.5).
+If the argv argument is non-NULL,
+<function>XSetWMProperties</function>
+calls
+<function>XSetCommand</function>,
+which sets the <property>WM_COMMAND</property> property (see section 14.2.1).
+Note that an argc of zero is allowed to indicate a zero-length command.
+Note also that the hostname of this machine is stored using
+<function>XSetWMClientMachine</function>
+(see section 14.2.2).
+</para>
+<para>
+<!-- .LP -->
+If the normal_hints argument is non-NULL,
+<function>XSetWMProperties</function>
+calls
+<function>XSetWMNormalHints</function>,
+which sets the <property>WM_NORMAL_HINTS</property> property (see section 14.1.7).
+If the wm_hints argument is non-NULL,
+<function>XSetWMProperties</function>
+calls
+<function>XSetWMHints</function>,
+which sets the <property>WM_HINTS</property> property (see section 14.1.6).
+</para>
+<para>
+<!-- .LP -->
+If the class_hints argument is non-NULL,
+<function>XSetWMProperties</function>
+calls
+<function>XSetClassHint</function>,
+which sets the <property>WM_CLASS</property> property (see section 14.1.8).
+If the res_name member in the
+<structname>XClassHint</structname>
+structure is set to the NULL pointer and the RESOURCE_NAME environment
+variable is set,
+then the value of the environment variable is substituted for res_name.
+If the res_name member is NULL,
+the environment variable is not set,
+and argv and argv[0] are set,
+then the value of argv[0], stripped of
+any directory prefixes, is substituted for res_name.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetWMProperties</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Client_to_Session_Manager_Communication">
+<title>Client to Session Manager Communication</title>
+<!-- .XS -->
+<!-- (SN Client to Session Manager Communication -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This section discusses how to:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Set and read the <property>WM_COMMAND</property> property
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Set and read the <property>WM_CLIENT_MACHINE</property> property
+ </para>
+ </listitem>
+</itemizedlist>
+<sect2 id="Setting_and_Reading_the_WM_COMMAND_Property">
+<title>Setting and Reading the WM_COMMAND Property</title>
+<!-- .XS -->
+<!-- (SN Setting and Reading the WM_COMMAND Property -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set and read
+the <property>WM_COMMAND</property> property for a given window.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set a window's <property>WM_COMMAND</property> property, use
+<function>XSetCommand</function>.
+<indexterm significance="preferred"><primary>XSetCommand</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetcommand'>
+<funcprototype>
+ <funcdef><function>XSetCommand</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>char<parameter> **argv</parameter></paramdef>
+ <paramdef>int<parameter> argc</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>argv</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the application's argument list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>argc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of arguments.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetCommand</function>
+function sets the command and arguments used to invoke the
+application.
+(Typically, argv is the argv array of your main program.)
+If the strings are not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+<function>XSetCommand</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To read a window's <property>WM_COMMAND</property> property, use
+<function>XGetCommand</function>.
+<indexterm significance="preferred"><primary>XGetCommand</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetcommand'>
+<funcprototype>
+ <funcdef>Status <function>XGetCommand</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>char<parameter> ***argv_return</parameter></paramdef>
+ <paramdef>int<parameter> *argc_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>argv_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the application's argument list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>argc_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of arguments returned.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetCommand</function>
+function reads the <property>WM_COMMAND</property> property from the specified window
+and returns a string list.
+If the <property>WM_COMMAND</property> property exists,
+it is of type STRING and format 8.
+If sufficient memory can be allocated to contain the string list,
+<function>XGetCommand</function>
+fills in the argv_return and argc_return arguments
+and returns a nonzero status.
+Otherwise, it returns a zero status.
+If the data returned by the server is in the Latin Portable Character Encoding,
+then the returned strings are in the Host Portable Character Encoding.
+Otherwise, the result is implementation-dependent.
+To free the memory allocated to the string list, use
+<function>XFreeStringList</function>.
+</para>
+</sect2>
+<sect2 id="Setting_and_Reading_the_WM_CLIENT_MACHINE_Property">
+<title>Setting and Reading the WM_CLIENT_MACHINE Property</title>
+<!-- .XS -->
+<!-- (SN Setting and Reading the WM_CLIENT_MACHINE Property -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set and read
+the <property>WM_CLIENT_MACHINE</property> property for a given window.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set a window's <property>WM_CLIENT_MACHINE</property> property, use
+<function>XSetWMClientMachine</function>.
+<indexterm significance="preferred"><primary>XSetWMClientMachine</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetwmclientmachine'>
+<funcprototype>
+ <funcdef>void <function>XSetWMClientMachine</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>text_prop</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XTextProperty</structname>
+structure to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetWMClientMachine</function>
+convenience function calls
+<function>XSetTextProperty</function>
+to set the <property>WM_CLIENT_MACHINE</property> property.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To read a window's <property>WM_CLIENT_MACHINE</property> property, use
+<function>XGetWMClientMachine</function>.
+<indexterm significance="preferred"><primary>XGetWMClientMachine</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetwmclientmachine'>
+<funcprototype>
+ <funcdef>Status <function>XGetWMClientMachine</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XTextProperty<parameter> *text_prop_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>text_prop_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the
+<structname>XTextProperty</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetWMClientMachine</function>
+convenience function performs an
+<function>XGetTextProperty</function>
+on the <property>WM_CLIENT_MACHINE</property> property.
+It returns a nonzero status on success;
+otherwise, it returns a zero status.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Standard_Colormaps">
+<title>Standard Colormaps</title>
+<!-- .XS -->
+<!-- (SN Standard Colormaps -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Applications with color palettes, smooth-shaded drawings, or digitized
+images demand large numbers of colors.
+In addition, these applications often require an efficient mapping
+from color triples to pixel values that display the appropriate colors.
+</para>
+<para>
+<!-- .LP -->
+As an example, consider a three-dimensional display program that wants
+to draw a smoothly shaded sphere.
+At each pixel in the image of the sphere,
+the program computes the intensity and color of light
+reflected back to the viewer.
+The result of each computation is a triple of red, green, and blue (<acronym>RGB</acronym>)
+coefficients in the range 0.0 to 1.0.
+To draw the sphere, the program needs a colormap that provides a
+large range of uniformly distributed colors.
+The colormap should be arranged so that the program can
+convert its <acronym>RGB</acronym> triples into pixel values very quickly,
+because drawing the entire sphere requires many such
+conversions.
+</para>
+<para>
+<!-- .LP -->
+On many current workstations,
+the display is limited to 256 or fewer colors.
+Applications must allocate colors carefully,
+not only to make sure they cover the entire range they need
+but also to make use of as many of the available colors as possible.
+On a typical X display,
+many applications are active at once.
+Most workstations have only one hardware look-up table for colors,
+so only one application colormap can be installed at a given time.
+The application using the installed colormap is displayed correctly,
+and the other applications go technicolor and are
+displayed with false colors.
+</para>
+<para>
+<!-- .LP -->
+As another example, consider a user who is running an
+image processing program to display earth-resources data.
+The image processing program needs a colormap set up with 8 reds,
+8 greens, and 4 blues, for a total of 256 colors.
+Because some colors are already in use in the default colormap,
+the image processing program allocates and installs a new colormap.
+</para>
+<para>
+<!-- .LP -->
+The user decides to alter some of the colors in the image
+by invoking a color palette program to mix and choose colors.
+The color palette program also needs a
+colormap with eight reds, eight greens, and four blues, so just like
+the image processing program, it must allocate and
+install a new colormap.
+</para>
+<para>
+<!-- .LP -->
+Because only one colormap can be installed at a time,
+the color palette may be displayed incorrectly
+whenever the image processing program is active.
+Conversely, whenever the palette program is active,
+the image may be displayed incorrectly.
+The user can never match or compare colors in the palette and image.
+Contention for colormap resources can be reduced if applications
+with similar color needs share colormaps.
+</para>
+<para>
+<!-- .LP -->
+The image processing program and the color palette program
+could share the same colormap if there existed a convention that described
+how the colormap was set up.
+Whenever either program was active,
+both would be displayed correctly.
+</para>
+<para>
+<!-- .LP -->
+The standard colormap properties define a set of commonly used
+colormaps.
+Applications that share these colormaps and conventions display
+true colors more often and provide a better interface to the user.
+</para>
+<para>
+<!-- .LP -->
+Standard colormaps allow applications to share commonly used color
+resources.
+This allows many applications to be displayed in true colors
+simultaneously, even when each application needs an entirely filled
+colormap.
+</para>
+<para>
+<!-- .LP -->
+Several standard colormaps are described in this section.
+Usually, a window manager creates these colormaps.
+Applications should use the standard colormaps if they already exist.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To allocate an
+<structname>XStandardColormap</structname>
+structure, use
+<function>XAllocStandardColormap</function>.
+</para>
+
+<para>
+XStandardColormap *XAllocStandardColormap()
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAllocStandardColormap</function>
+function allocates and returns a pointer to an
+<structname>XStandardColormap</structname>
+structure.
+Note that all fields in the
+<structname>XStandardColormap</structname>
+structure are initially set to zero.
+If insufficient memory is available,
+<function>XAllocStandardColormap</function>
+returns NULL.
+To free the memory allocated to this structure,
+use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XStandardColormap</structname>
+structure contains:
+</para>
+<literallayout class="monospaced">
+/* Hints */
+
+#define ReeaseByFreeingColormap ((XID)1L)
+
+/* Values */
+
+typedef struct {
+ Colormap colormap;
+ unsigned long red_max;
+ unsigned long red_mult;
+ unsigned long green_max;
+ unsigned long green_mult;
+ unsigned long blue_max;
+ unsigned long blue_mult;
+ unsigned long base_pixel;
+ VisualID visualid;
+ XID killid;
+} XStandardColormap;
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The colormap member is the colormap created by the
+<function>XCreateColormap</function>
+function.
+The red_max, green_max, and blue_max members give the maximum
+red, green, and blue values, respectively.
+Each color coefficient ranges from zero to its max, inclusive.
+For example,
+a common colormap allocation is 3/3/2 (3 planes for red, 3
+planes for green, and 2 planes for blue).
+This colormap would have red_max = 7, green_max = 7,
+and blue_max = 3.
+An alternate allocation that uses only 216 colors is red_max = 5,
+green_max = 5, and blue_max = 5.
+</para>
+<para>
+<!-- .LP -->
+The red_mult, green_mult, and blue_mult members give the
+scale factors used to compose a full pixel value.
+(See the discussion of the base_pixel members for further information.)
+For a 3/3/2 allocation, red_mult might be 32,
+green_mult might be 4, and blue_mult might be 1.
+For a 6-colors-each allocation, red_mult might be 36,
+green_mult might be 6, and blue_mult might be 1.
+</para>
+<para>
+<!-- .LP -->
+The base_pixel member gives the base pixel value used to
+compose a full pixel value.
+Usually, the base_pixel is obtained from a call to the
+<function>XAllocColorPlanes</function>
+function.
+Given integer red, green, and blue coefficients in their appropriate
+ranges, one then can compute a corresponding pixel value by
+using the following expression:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 1.5i -->
+<!-- .ta .5i 1.5i -->
+(r * red_mult + g * green_mult + b * blue_mult + base_pixel) &amp; 0xFFFFFFFF
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+For
+<symbol>GrayScale</symbol>
+colormaps,
+only the colormap, red_max, red_mult,
+and base_pixel members are defined.
+The other members are ignored.
+To compute a
+<symbol>GrayScale</symbol>
+pixel value, use the following expression:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .5i 1.5i -->
+<!-- .ta .5i 1.5i -->
+(gray * red_mult + base_pixel) &amp; 0xFFFFFFFF
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+Negative multipliers can be represented by converting the 2's
+complement representation of the multiplier into an unsigned long and
+storing the result in the appropriate _mult field.
+The step of masking by 0xFFFFFFFF effectively converts the resulting
+positive multiplier into a negative one.
+The masking step will take place automatically on many machine architectures,
+depending on the size of the integer type used to do the computation.
+</para>
+<para>
+<!-- .LP -->
+The visualid member gives the ID number of the visual from which the
+colormap was created.
+The killid member gives a resource ID that indicates whether
+the cells held by this standard colormap are to be released
+by freeing the colormap ID or by calling the
+<function>XKillClient</function>
+function on the indicated resource.
+(Note that this method is necessary for allocating out of an existing colormap.)
+</para>
+<para>
+<!-- .LP -->
+The properties containing the
+<structname>XStandardColormap</structname>
+information have
+the type RGB_COLOR_MAP.
+</para>
+<para>
+<!-- .LP -->
+The remainder of this section discusses standard colormap properties and atoms
+as well as how to manipulate standard colormaps.
+</para>
+<sect2 id="Standard_Colormap_Properties_and_Atoms">
+<title>Standard Colormap Properties and Atoms</title>
+<!-- .XS -->
+<!-- (SN Standard Colormap Properties and Atoms -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Standard Colormaps</primary></indexterm>
+<indexterm><primary>Colormaps</primary><secondary>standard</secondary></indexterm>
+Several standard colormaps are available.
+Each standard colormap is defined by a property,
+and each such property is identified by an atom.
+The following list names the atoms and describes the colormap
+associated with each one.
+The
+<filename class="headerfile">&lt;X11/Xatom.h&gt;</filename>
+<indexterm type="file"><primary><filename class="headerfile">X11/Xatom.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xatom.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xatom.h&gt;</filename></secondary></indexterm>
+header file contains the definitions for each of the following atoms,
+which are prefixed with XA_.
+</para>
+
+
+
+<variablelist>
+ <varlistentry>
+ <term>RGB_DEFAULT_MAP</term>
+ <listitem>
+ <para>
+This atom names a property.
+The value of the property is an array of
+<structname>XStandardColormap</structname>
+structures.
+Each entry in the array describes an <acronym>RGB</acronym> subset of the default color
+map for the Visual specified by visual_id.
+ </para>
+ <para>
+Some applications only need a few <acronym>RGB</acronym> colors and
+may be able to allocate them from the system default colormap.
+This is the ideal situation because the fewer colormaps that are
+active in the system the more applications are displayed
+with correct colors at all times.
+ </para>
+ <para>
+A typical allocation for the RGB_DEFAULT_MAP on 8-plane displays
+is 6 reds, 6 greens, and 6 blues.
+This gives 216 uniformly distributed colors
+(6 intensities of 36 different hues) and still leaves 40 elements
+of a 256-element colormap available for special-purpose colors
+for text, borders, and so on.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>RGB_BEST_MAP</term>
+ <listitem>
+ <para>
+This atom names a property. The value of the property is an
+<structname>XStandardColormap</structname>.
+ </para>
+ <para>
+The property defines the best <acronym>RGB</acronym> colormap available on
+the screen.
+(Of course, this is a subjective evaluation.)
+Many image processing and three-dimensional applications need to
+use all available colormap cells and to distribute as many
+perceptually distinct colors as possible over those cells.
+This implies that there may be more green values available than
+red, as well as more green or red than blue.
+ </para>
+ <para>
+For an 8-plane
+<symbol>PseudoColor</symbol>
+visual,
+RGB_BEST_MAP is likely to be a 3/3/2 allocation.
+For a 24-plane
+<symbol>DirectColor</symbol>
+visual,
+RGB_BEST_MAP is normally an 8/8/8 allocation.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>RGB_RED_MAP,RGB_GREEN_MAP,RGB_BLUE_MAP</term>
+ <listitem>
+ <para>
+These atoms name properties.
+The value of each property is an
+<structname>XStandardColormap</structname>.
+ </para>
+ <para>
+The properties define all-red, all-green, and all-blue
+colormaps, respectively.
+These maps are used by applications that want to make color-separated
+images.
+For example, a user might generate a full-color image
+on an 8-plane display both by rendering an image three times
+(once with high color resolution in red, once with green,
+and once with blue) and by multiply exposing a single frame in a camera.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>RGB_GRAY_MAP</term>
+ <listitem>
+ <para>
+This atom names a property.
+The value of the property is an
+<structname>XStandardColormap</structname>.
+ </para>
+ <para>
+The property describes the best
+<symbol>GrayScale</symbol>
+colormap available on the screen.
+As previously mentioned,
+only the colormap, red_max, red_mult, and base_pixel members of the
+<structname>XStandardColormap</structname>
+structure are used for
+<symbol>GrayScale</symbol>
+colormaps.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+</sect2>
+
+<sect2 id="Setting_and_Obtaining_Standard_Colormaps">
+<title>Setting and Obtaining Standard Colormaps</title>
+<!-- .XS -->
+<!-- (SN Setting and Obtaining Standard Colormaps -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to set and obtain an
+<structname>XStandardColormap</structname>
+structure.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To set an
+<structname>XStandardColormap</structname>
+structure, use
+<function>XSetRGBColormaps</function>.
+<indexterm significance="preferred"><primary>XSetRGBColormaps</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetrgbcolormaps'>
+<funcprototype>
+ <funcdef>void <function>XSetRGBColormaps</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XStandardColormap<parameter> *std_colormap</parameter></paramdef>
+ <paramdef>int<parameter> count</parameter></paramdef>
+ <paramdef>Atom<parameter> property</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>std_colormap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>XStandardColormap</structname>
+structure to be used.
+<!-- .ds Cn colormaps -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of (Cn.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>property</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the property name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetRGBColormaps</function>
+function replaces the <acronym>RGB</acronym> colormap definition in the specified property
+on the named window.
+If the property does not already exist,
+<function>XSetRGBColormaps</function>
+sets the <acronym>RGB</acronym> colormap definition in the specified property
+on the named window.
+The property is stored with a type of RGB_COLOR_MAP and a format of 32.
+Note that it is the caller's responsibility to honor the <acronym>ICCCM</acronym>
+restriction that only RGB_DEFAULT_MAP contain more than one definition.
+</para>
+<para>
+<!-- .LP -->
+The
+<function>XSetRGBColormaps</function>
+function usually is only used by window or session managers.
+To create a standard colormap,
+follow this procedure:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Open a new connection to the same server.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Grab the server.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+See if the property is on the property list of the root window for the screen.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+If the desired property is not present:
+<!-- .RS -->
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Create a colormap (unless you are using the default colormap of the screen).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Determine the color characteristics of the visual.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Allocate cells in the colormap (or create it with
+<symbol>AllocAll</symbol>).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Call
+<function>XStoreColors</function>
+to store appropriate color values in the colormap.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Fill in the descriptive members in the
+<structname>XStandardColormap</structname>
+structure.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Attach the property to the root window.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Use
+<function>XSetCloseDownMode</function>
+to make the resource permanent.
+<!-- .RE -->
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Ungrab the server.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+<function>XSetRGBColormaps</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadAtom</errorname>,
+and
+<errorname>BadWindow</errorname>
+errors.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To obtain the
+<structname>XStandardColormap</structname>
+structure associated with the specified property, use
+<function>XGetRGBColormaps</function>.
+<indexterm significance="preferred"><primary>XGetRGBColormaps</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetrgbcolormaps'>
+<funcprototype>
+ <funcdef>Status <function>XGetRGBColormaps</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Window<parameter> w</parameter></paramdef>
+ <paramdef>XStandardColormap<parameter> **std_colormap_return</parameter></paramdef>
+ <paramdef>int<parameter> *count_return</parameter></paramdef>
+ <paramdef>Atom<parameter> property</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>w</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the window.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>std_colormap_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the
+<structname>XStandardColormap</structname>
+structure.
+<!-- .ds Cn colormaps -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>count_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of (Cn.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>property</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the property name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetRGBColormaps</function>
+function returns the <acronym>RGB</acronym> colormap definitions stored
+in the specified property on the named window.
+If the property exists, is of type RGB_COLOR_MAP, is of format 32,
+and is long enough to contain a colormap definition,
+<function>XGetRGBColormaps</function>
+allocates and fills in space for the returned colormaps
+and returns a nonzero status.
+If the visualid is not present,
+<function>XGetRGBColormaps</function>
+assumes the default visual for the screen on which the window is located;
+if the killid is not present,
+<symbol>None</symbol>
+is assumed, which indicates that the resources cannot be released.
+Otherwise,
+none of the fields are set, and
+<function>XGetRGBColormaps</function>
+returns a zero status.
+Note that it is the caller's responsibility to honor the <acronym>ICCCM</acronym>
+restriction that only RGB_DEFAULT_MAP contain more than one definition.
+</para>
+<para>
+<!-- .LP -->
+<function>XGetRGBColormaps</function>
+can generate
+<errorname>BadAtom</errorname>
+and
+<errorname>BadWindow</errorname>
+errors.
+<!-- .bp -->
+
+</para>
+</sect2>
+</sect1>
+</chapter>
diff --git a/libX11/specs/libX11/CH15.xml b/libX11/specs/libX11/CH15.xml
index 753dff177..7abc6173e 100644
--- a/libX11/specs/libX11/CH15.xml
+++ b/libX11/specs/libX11/CH15.xml
@@ -1,2491 +1,2491 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<chapter id="resource_manager_functions">
-<title>Resource Manager Functions</title>
-<!-- .sp 2 -->
-<!-- .nr H1 15 -->
-<!-- .nr H2 0 -->
-<!-- .nr H3 0 -->
-<!-- .nr H4 0 -->
-<!-- .nr H5 0 -->
-<!-- .na -->
-<para>
-<!-- .LP -->
-<!-- .XS -->
-<!-- Chapter 15: Resource Manager Functions -->
-<!-- .XE -->
-A program often needs a variety of options in the X environment
-(for example, fonts, colors, icons, and cursors).
-Specifying all of these options on the command line is awkward
-because users may want to customize many aspects of the program
-and need a convenient way to establish these customizations as
-the default settings.
-The resource manager is provided for this purpose.
-Resource specifications are usually stored in human-readable files
-and in server properties.
-</para>
-<para>
-<!-- .LP -->
-The resource manager is a database manager with a twist.
-In most database systems,
-you perform a query using an imprecise specification,
-and you get back a set of records.
-The resource manager, however, allows you to specify a large
-set of values with an imprecise specification, to query the database
-with a precise specification, and to get back only a single value.
-This should be used by applications that need to know what the
-user prefers for colors, fonts, and other resources.
-It is this use as a database for dealing with X resources that
-inspired the name "Resource Manager,"
-although the resource manager can be and is used in other ways.
-</para>
-<para>
-<!-- .LP -->
-For example,
-a user of your application may want to specify
-that all windows should have a blue background
-but that all mail-reading windows should have a red background.
-With well-engineered and coordinated applications,
-a user can define this information using only two lines of specifications.
-</para>
-<para>
-<!-- .LP -->
-As an example of how the resource manager works,
-consider a mail-reading application called xmh.
-Assume that it is designed so that it uses a
-complex window hierarchy all the way down to individual command buttons,
-which may be actual small subwindows in some toolkits.
-These are often called objects or widgets.
-In such toolkit systems,
-each user interface object can be composed of other objects
-and can be assigned a name and a class.
-Fully qualified names or classes can have arbitrary numbers of component names,
-but a fully qualified name always has the same number of component names as a
-fully qualified class.
-This generally reflects the structure of the application as composed
-of these objects, starting with the application itself.
-</para>
-<para>
-<!-- .LP -->
-For example, the xmh mail program has a name "xmh" and is one
-of a class of "Mail" programs.
-By convention, the first character of class components is capitalized,
-and the first letter of name components is in lowercase.
-Each name and class finally has an attribute
-(for example, "foreground" or "font").
-If each window is properly assigned a name and class,
-it is easy for the user to specify attributes of any portion
-of the application.
-</para>
-<para>
-<!-- .LP -->
-At the top level,
-the application might consist of a paned window (that is, a window divided
-into several sections) named "toc".
-One pane of the paned window is a button box window named "buttons"
-and is filled with command buttons.
-One of these command buttons is used to incorporate
-new mail and has the name "incorporate".
-This window has a fully qualified name, "xmh.toc.buttons.incorporate",
-and a fully qualified class, "Xmh.Paned.Box.Command".
-Its fully qualified name is the name of its parent, "xmh.toc.buttons",
-followed by its name, "incorporate".
-Its class is the class of its parent, "Xmh.Paned.Box",
-followed by its particular class, "Command".
-The fully qualified name of a resource is
-the attribute's name appended to the object's fully qualified
-name, and the fully qualified class is its class appended to the object's
-class.
-</para>
-<para>
-<!-- .LP -->
-The incorporate button might need the following resources:
-Title string,
-Font,
-Foreground color for its inactive state,
-Background color for its inactive state,
-Foreground color for its active state, and
-Background color for its active state.
-Each resource is considered
-to be an attribute of the button and, as such, has a name and a class.
-For example, the foreground color for the button in
-its active state might be named "activeForeground",
-and its class might be "Foreground".
-</para>
-<para>
-<!-- .LP -->
-When an application looks up a resource (for example, a color),
-it passes the complete name and complete class of the resource
-to a look-up routine.
-The resource manager compares this complete specification
-against the incomplete specifications of entries in the resource
-database, finds the best match, and returns the corresponding
-value for that entry.
-</para>
-<para>
-<!-- .LP -->
-The definitions for the resource manager are contained in
-<filename class="headerfile">&lt;X11/Xresource.h&gt;</filename>.
-<indexterm type="file"><primary><filename class="headerfile">X11/Xresource.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xresource.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xresource.h&gt;</filename></secondary></indexterm>
-</para>
-<sect1 id="Resource_File_Syntax">
-<title>Resource File Syntax</title>
-<!-- .XS -->
-<!-- (SN Resource File Syntax -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The syntax of a resource file is a sequence of resource lines
-terminated by newline characters or the end of the file.
-The syntax of an individual resource line is:
-</para>
-<para>
-<!-- .LP -->
-<!-- .\" Start marker code here -->
-<literallayout class="monospaced">
-<!-- .TA 1.5i 1.75i -->
-<!-- .ta 1.5i 1.75i -->
-ResourceLine = Comment | IncludeFile | ResourceSpec | &lt;empty line&gt;
-Comment = "!" {&lt;any character except null or newline&gt;}
-IncludeFile = "#" WhiteSpace "include" WhiteSpace FileName WhiteSpace
-FileName = &lt;valid filename for operating system&gt;
-ResourceSpec = WhiteSpace ResourceName WhiteSpace ":" WhiteSpace Value
-ResourceName = [Binding] {Component Binding} ComponentName
-Binding = "." | "*"
-WhiteSpace = {&lt;space&gt; | &lt;horizontal tab&gt;}
-Component = "?" | ComponentName
-ComponentName = NameChar {NameChar}
-NameChar = "a"-"z" | "A"-"Z" | "0"-"9" | "_" | "-"
-Value = {&lt;any character except null or unescaped newline&gt;}
-</literallayout>
-<!-- .\" End marker code here -->
-</para>
-<para>
-<!-- .LP -->
-Elements separated by vertical bar (|) are alternatives.
-Curly braces ({......}) indicate zero or more repetitions
-of the enclosed elements.
-Square brackets ([......]) indicate that the enclosed element is optional.
-Quotes ("......") are used around literal characters.
-</para>
-<para>
-<!-- .LP -->
-IncludeFile lines are interpreted by replacing the line with the
-contents of the specified file.
-The word "include" must be in lowercase.
-The file name is interpreted relative to the directory of the file in
-which the line occurs (for example, if the file name contains no
-directory or contains a relative directory specification).
-</para>
-<para>
-<!-- .LP -->
-If a ResourceName contains a contiguous sequence of two or more Binding
-characters, the sequence will be replaced with a single ".." character
-if the sequence contains only ".." characters;
-otherwise, the sequence will be replaced with a single "*" character.
-</para>
-<para>
-<!-- .LP -->
-A resource database never contains more than one entry for a given
-ResourceName. If a resource file contains multiple lines with the
-same ResourceName, the last line in the file is used.
-</para>
-<para>
-<!-- .LP -->
-Any white space characters before or after the name or colon in a ResourceSpec
-are ignored.
-To allow a Value to begin with white space,
-the two-character sequence "\\<emphasis remap='I'>space</emphasis>" (backslash followed by space)
-is recognized and replaced by a space character,
-and the two-character sequence "\\<emphasis remap='I'>tab</emphasis>"
-(backslash followed by horizontal tab)
-is recognized and replaced by a horizontal tab character.
-To allow a Value to contain embedded newline characters,
-the two-character sequence "\\n" is recognized and replaced by a
-newline character.
-To allow a Value to be broken across multiple lines in a text file,
-the two-character sequence "\\<emphasis remap='I'>newline</emphasis>"
-(backslash followed by newline) is
-recognized and removed from the value.
-To allow a Value to contain arbitrary character codes,
-the four-character sequence "\\<emphasis remap='I'>nnn</emphasis>",
-where each <emphasis remap='I'>n</emphasis> is a digit character in the range of "0"-"7",
-is recognized and replaced with a single byte that contains
-the octal value specified by the sequence.
-Finally, the two-character sequence "\newline" is recognized
-and replaced with a single backslash.
-</para>
-<para>
-<!-- .LP -->
-As an example of these sequences,
-the following resource line contains a value consisting of four
-characters: a backslash, a null, a "z", and a newline:
-<literallayout class="monospaced">
-magic.values: \\000\
-z\n
-</literallayout>
-</para>
-</sect1>
-<sect1 id="Resource_Manager_Matching_Rules">
-<title>Resource Manager Matching Rules</title>
-<!-- .XS -->
-<!-- (SN Resource Manager Matching Rules -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The algorithm for determining which resource database entry
-matches a given query is the heart of the resource manager.
-All queries must fully specify the name and class of the desired resource
-(use of the characters "*" and "?" is not permitted).
-The library supports up to 100 components in a full name or class.
-Resources are stored in the database with only partially specified
-names and classes, using pattern matching constructs.
-An asterisk (*) is a loose binding and is used to represent any number
-of intervening components, including none.
-A period (.) is a tight binding and is used to separate immediately
-adjacent components.
-A question mark (?) is used to match any single component name or class.
-A database entry cannot end in a loose binding;
-the final component (which cannot be the character "?") must be specified.
-The lookup algorithm searches the database for the entry that most
-closely matches (is most specific for) the full name and class being queried.
-When more than one database entry matches the full name and class,
-precedence rules are used to select just one.
-</para>
-<para>
-<!-- .LP -->
-The full name and class are scanned from left to right (from highest
-level in the hierarchy to lowest), one component at a time.
-At each level, the corresponding component and/or binding of each
-matching entry is determined, and these matching components and
-bindings are compared according to precedence rules.
-Each of the rules is applied at each level before moving to the next level,
-until a rule selects a single entry over all others.
-The rules, in order of precedence, are:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-An entry that contains a matching component (whether name, class,
-or the character "?")
-takes precedence over entries that elide the level (that is, entries
-that match the level in a loose binding).
- </para>
- </listitem>
- <listitem>
- <para>
-An entry with a matching name takes precedence over both
-entries with a matching class and entries that match using the character "?".
-An entry with a matching class takes precedence over
-entries that match using the character "?".
- </para>
- </listitem>
- <listitem>
- <para>
-An entry preceded by a tight binding takes precedence over entries
-preceded by a loose binding.
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-To illustrate these rules,
-consider the following resource database entries:
-<literallayout class="monospaced">
-<!-- .TA 2.5i 3.5i -->
-<!-- .ta 2.5i 3.5i -->
-xmh*Paned*activeForeground: red <emphasis remap='I'>(entry A)</emphasis>
-*incorporate.Foreground: blue <emphasis remap='I'>(entry B)</emphasis>
-xmh.toc*Command*activeForeground: green <emphasis remap='I'>(entry C)</emphasis>
-xmh.toc*?.Foreground: white <emphasis remap='I'>(entry D)</emphasis>
-xmh.toc*Command.activeForeground: black <emphasis remap='I'>(entry E)</emphasis>
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-Consider a query for the resource:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA 3.5i -->
-<!-- .ta 3.5i -->
-xmh.toc.messagefunctions.incorporate.activeForeground <emphasis remap='I'>(name)</emphasis>
-Xmh.Paned.Box.Command.Foreground <emphasis remap='I'>(class)</emphasis>
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-At the first level (xmh, Xmh), rule 1 eliminates entry B.
-At the second level (toc, Paned), rule 2 eliminates entry A.
-At the third level (messagefunctions, Box), no entries are eliminated.
-At the fourth level (incorporate, Command), rule 2 eliminates entry D.
-At the fifth level (activeForeground, Foreground), rule 3 eliminates entry C.
-</para>
-</sect1>
-<sect1 id="Quarks">
-<title>Quarks</title>
-<!-- .XS -->
-<!-- (SN Quarks -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Most uses of the resource manager involve defining names,
-classes, and representation types as string constants.
-However, always referring to strings in the resource manager can be slow,
-because it is so heavily used in some toolkits.
-To solve this problem,
-a shorthand for a string is used in place of the string
-in many of the resource manager functions.
-Simple comparisons can be performed rather than string comparisons.
-The shorthand name for a string is called a quark and is the
-type
-<type>XrmQuark</type>.
-On some occasions,
-you may want to allocate a quark that has no string equivalent.
-</para>
-<para>
-<!-- .LP -->
-A quark is to a string what an atom is to a string in the server,
-but its use is entirely local to your application.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To allocate a new quark, use
-<function>XrmUniqueQuark</function>.
-</para>
-<indexterm significance="preferred"><primary>XrmUniqueQuark</primary></indexterm>
-<!-- .sM -->
-<para>XrmQuark XrmUniqueQuark()</para>
-<!-- .FN -->
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmUniqueQuark</function>
-function allocates a quark that is guaranteed not to represent any string that
-is known to the resource manager.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-Each name, class, and representation type is typedef'd as an
-<type>XrmQuark</type>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<literallayout class="monospaced">
-typedef int XrmQuark, *XrmQuarkList;
-typedef XrmQuark XrmName;
-typedef XrmQuark XrmClass;
-typedef XrmQuark XrmRepresentation;
-#define NULLQUARK ((XrmQuark) 0)
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Lists are represented as null-terminated arrays of quarks.
-The size of the array must be large enough for the number of components used.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<literallayout class="monospaced">
-typedef XrmQuarkList XrmNameList;
-typedef XrmQuarkList XrmClassList;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To convert a string to a quark, use
-<function>XrmStringToQuark</function>
-or
-<function>XrmPermStringToQuark</function>.
-</para>
-<literallayout class="monospaced">
-#define XrmStringToName(string) XrmStringToQuark(string)
-#define XrmStringToClass(string) XrmStringToQuark(string)
-#define XrmStringToRepresentation(string) XrmStringToQuark(string)
-</literallayout>
-
-<indexterm significance="preferred"><primary>XrmStringToQuark</primary></indexterm>
-<indexterm significance="preferred"><primary>XrmPermStringToQuark</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XrmQuark <function>XrmStringToQuark</function></funcdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<!-- .ds Ql -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the string for which a quark(Ql is to be allocated.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-These functions can be used to convert from string to quark representation.
-If the string is not in the Host Portable Character Encoding,
-the conversion is implementation-dependent.
-The string argument to
-<function>XrmStringToQuark</function>
-need not be permanently allocated storage.
-<function>XrmPermStringToQuark</function>
-is just like
-<function>XrmStringToQuark</function>,
-except that Xlib is permitted to assume the string argument is permanently
-allocated,
-and, hence, that it can be used as the value to be returned by
-<function>XrmQuarkToString</function>.
-</para>
-<para>
-<!-- .LP -->
-For any given quark, if
-<function>XrmStringToQuark</function>
-returns a non-NULL value,
-all future calls will return the same value (identical address).
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To convert a quark to a string, use
-<function>XrmQuarkToString</function>.
-</para>
-
-<literallayout class="monospaced">
-#define XrmNameToString(name) XrmQuarkToString(name)
-#define XrmClassToString(class) XrmQuarkToString(name)
-#define XrmRepresentationToString(type) XrmQuarkToString(type)
-</literallayout>
-<indexterm significance="preferred"><primary>XrmQuarkToString</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XrmQuarkToString</function></funcdef>
- <paramdef>XrmQuark<parameter> quark</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>quark</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the quark for which the equivalent string is desired.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-<!-- AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA -->
-<para>
-These functions can be used to convert from quark representation to string.
-The string pointed to by the return value must not be modified or freed.
-The returned string is byte-for-byte equal to the original
-string passed to one of the string-to-quark routines.
-If no string exists for that quark,
-<function>XrmQuarkToString</function>
-returns NULL.
-For any given quark, if
-<function>XrmQuarkToString</function>
-returns a non-NULL value,
-all future calls will return the same value (identical address).
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To convert a string with one or more components to a quark list, use
-<function>XrmStringToQuarkList</function>.
-</para>
-
-<literallayout class="monospaced">
-#define XrmStringToNameList(str,name) XrmStringToQuarkList((str), (name))
-#define XrmStringToClassList(str,class) XrmStringToQuarkList((str), (class))
-</literallayout>
-
-<indexterm significance="preferred"><primary>XrmStringToQuarkList</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmStringToQuarkList</function></funcdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
- <paramdef>XrmQuarkList<parameter> quarks_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<!-- .ds Ql \ list -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the string for which a quark(Ql is to be allocated.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>quarks_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the list of quarks.
-The caller must allocate sufficient space for the quarks list before calling
-<function>XrmStringToQuarkList</function>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmStringToQuarkList</function>
-function converts the null-terminated string (generally a fully qualified name)
-to a list of quarks.
-Note that the string must be in the valid ResourceName format
-(see section 15.1).
-If the string is not in the Host Portable Character Encoding,
-the conversion is implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-A binding list is a list of type
-<type>XrmBindingList</type>
-and indicates if components of name or class lists are bound tightly or loosely
-(that is, if wildcarding of intermediate components is specified).
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-typedef enum {XrmBindTightly, XrmBindLoosely} XrmBinding, *XrmBindingList;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<constant>XrmBindTightly</constant>
-indicates that a period separates the components, and
-<constant>XrmBindLoosely</constant>
-indicates that an asterisk separates the components.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To convert a string with one or more components to a binding list
-and a quark list, use
-<function>XrmStringToBindingQuarkList</function>.
-<indexterm significance="preferred"><primary>XrmStringToBindingQuarkList</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XrmStringToBindingQuarkList</function></funcdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
- <paramdef>XrmBindingList<parameter> bindings_return</parameter></paramdef>
- <paramdef>XrmQuarkList<parameter> quarks_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<!-- .ds Ql \ list -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the string for which a quark(Ql is to be allocated.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bindings_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the binding list.
-The caller must allocate sufficient space for the binding list before calling
-<function>XrmStringToBindingQuarkList</function>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>quarks_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the list of quarks.
-The caller must allocate sufficient space for the quarks list before calling
-<function>XrmStringToBindingQuarkList</function>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Component names in the list are separated by a period or
-an asterisk character.
-The string must be in the format of a valid ResourceName (see section 15.1).
-If the string does not start with a period or an asterisk,
-a tight binding is assumed.
-For example, the string ``*a.b*c'' becomes:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA .75i 1.5i 2.25i -->
-<!-- .ta .75i 1.5i 2.25i -->
-quarks: a b c
-bindings: loose tight loose
-</literallayout>
-</para>
-</sect1>
-<sect1 id="Creating_and_Storing_Databases">
-<title>Creating and Storing Databases</title>
-<!-- .XS -->
-<!-- (SN Creating and Storing Databases -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XrmDatabase</primary></indexterm>
-A resource database is an opaque type,
-<type>XrmDatabase</type>.
-Each database value is stored in an
-<type>XrmValue</type>
-structure.
-This structure consists of a size, an address, and a representation type.
-The size is specified in bytes.
-The representation type is a way for you to store data tagged by some
-application-defined type (for example, the strings ``font'' or ``color'').
-It has nothing to do with the C data type or with its class.
-The
-<type>XrmValue</type>
-structure is defined as:
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XrmValue</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-typedef struct {
- unsigned int size;
- XPointer addr;
-} XrmValue, *XrmValuePtr;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To initialize the resource manager, use
-<function>XrmInitialize</function>.
-<indexterm significance="preferred"><primary>XrmInitialize</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmInitialize</function></funcdef>
- <paramdef>void<parameter> XrmInitialize(\|)</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-To retrieve a database from disk, use
-<function>XrmGetFileDatabase</function>.
-<indexterm significance="preferred"><primary>XrmGetFileDatabase</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XrmDatabase <function>XrmGetFileDatabase</function></funcdef>
- <paramdef>char<parameter> *filename</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>filename</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database file name.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmGetFileDatabase</function>
-function opens the specified file,
-creates a new resource database, and loads it with the specifications
-read in from the specified file.
-The specified file should contain a sequence of entries in valid ResourceLine
-format (see section 15.1); the database that results from reading a file
-with incorrect syntax is implementation-dependent.
-The file is parsed in the current locale,
-and the database is created in the current locale.
-If it cannot open the specified file,
-<function>XrmGetFileDatabase</function>
-returns NULL.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To store a copy of a database to disk, use
-<function>XrmPutFileDatabase</function>.
-<indexterm significance="preferred"><primary>XrmPutFileDatabase</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmPutFileDatabase</function></funcdef>
- <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
- <paramdef>char<parameter> *stored_db</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the database that is to be used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>stored_db</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the file name for the stored database.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmPutFileDatabase</function>
-function stores a copy of the specified database in the specified file.
-Text is written to the file as a sequence of entries in valid
-ResourceLine format (see section 15.1).
-The file is written in the locale of the database.
-Entries containing resource names that are not in the Host Portable Character
-Encoding or containing values that are not in the encoding of the database
-locale, are written in an implementation-dependent manner.
-The order in which entries are written is implementation-dependent.
-Entries with representation types other than ``String'' are ignored.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain a pointer to the screen-independent resources of a display, use
-<function>XResourceManagerString</function>.
-<indexterm significance="preferred"><primary>XResourceManagerString</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XResourceManagerString</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XResourceManagerString</function>
-function returns the RESOURCE_MANAGER property from the server's root
-window of screen zero, which was returned when the connection was opened using
-<function>XOpenDisplay</function>.
-The property is converted from type STRING to the current locale.
-The conversion is identical to that produced by
-<function>XmbTextPropertyToTextList</function>
-for a single element STRING property.
-The returned string is owned by Xlib and should not be freed by the client.
-The property value must be in a format that is acceptable to
-<function>XrmGetStringDatabase</function>.
-If no property exists, NULL is returned.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain a pointer to the screen-specific resources of a screen, use
-<function>XScreenResourceString</function>.
-<indexterm significance="preferred"><primary>XScreenResourceString</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XScreenResourceString</function></funcdef>
- <paramdef>Screen<parameter> *screen</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the screen.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XScreenResourceString</function>
-function returns the SCREEN_RESOURCES property from the root window of the
-specified screen.
-The property is converted from type STRING to the current locale.
-The conversion is identical to that produced by
-<function>XmbTextPropertyToTextList</function>
-for a single element STRING property.
-The property value must be in a format that is acceptable to
-<function>XrmGetStringDatabase</function>.
-If no property exists, NULL is returned.
-The caller is responsible for freeing the returned string by using
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create a database from a string, use
-<function>XrmGetStringDatabase</function>.
-<indexterm significance="preferred"><primary>XrmGetStringDatabase</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XrmDatabase <function>XrmGetStringDatabase</function></funcdef>
- <paramdef>char<parameter> *data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the database contents using a string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmGetStringDatabase</function>
-function creates a new database and stores the resources specified
-in the specified null-terminated string.
-<function>XrmGetStringDatabase</function>
-is similar to
-<function>XrmGetFileDatabase</function>
-except that it reads the information out of a string instead of out of a file.
-The string should contain a sequence of entries in valid ResourceLine
-format (see section 15.1) terminated by a null character;
-the database that results from using a string
-with incorrect syntax is implementation-dependent.
-The string is parsed in the current locale,
-and the database is created in the current locale.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the locale name of a database, use
-<function>XrmLocaleOfDatabase</function>.
-<indexterm significance="preferred"><primary>XrmLocaleOfDatabase</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XrmLocaleOfDatabase</function></funcdef>
- <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmLocaleOfDatabase</function>
-function returns the name of the locale bound to the specified
-database, as a null-terminated string.
-The returned locale name string is owned by Xlib and should not be
-modified or freed by the client.
-Xlib is not permitted to free the string until the database is destroyed.
-Until the string is freed,
-it will not be modified by Xlib.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To destroy a resource database and free its allocated memory, use
-<function>XrmDestroyDatabase</function>.
-<indexterm significance="preferred"><primary>XrmDestroyDatabase</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmDestroyDatabase</function></funcdef>
- <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If database is NULL,
-<function>XrmDestroyDatabase</function>
-returns immediately.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To associate a resource database with a display, use
-<function>XrmSetDatabase</function>.
-<indexterm significance="preferred"><primary>XrmSetDatabase</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmSetDatabase</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmSetDatabase</function>
-function associates the specified resource database (or NULL)
-with the specified display.
-The database previously associated with the display (if any) is not destroyed.
-A client or toolkit may find this function convenient for retaining a database
-once it is constructed.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To get the resource database associated with a display, use
-<function>XrmGetDatabase</function>.
-<indexterm significance="preferred"><primary>XrmGetDatabase</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XrmDatabase <function>XrmGetDatabase</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmGetDatabase</function>
-function returns the database associated with the specified display.
-It returns NULL if a database has not yet been set.
-</para>
-</sect1>
-<sect1 id="Merging_Resource_Databases">
-<title>Merging Resource Databases</title>
-<!-- .XS -->
-<!-- (SN Merging Resource Databases -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To merge the contents of a resource file into a database, use
-<function>XrmCombineFileDatabase</function>.
-<indexterm significance="preferred"><primary>XrmCombineFileDatabase</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XrmCombineFileDatabase</function></funcdef>
- <paramdef>char<parameter> *filename</parameter></paramdef>
- <paramdef>XrmDatabase<parameter> *target_db</parameter></paramdef>
- <paramdef>Bool<parameter> override</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>filename</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database file name.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>target_db</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database into which the source
-database is to be merged.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>override</emphasis>
- </term>
- <listitem>
- <para>
-Specifies whether source entries override target ones.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmCombineFileDatabase</function>
-function merges the contents of a resource file into a database.
-If the same specifier is used for an entry in both the file and
-the database,
-the entry in the file will replace the entry in the database
-if override is
-<symbol>True</symbol>;
-otherwise, the entry in the file is discarded.
-The file is parsed in the current locale.
-If the file cannot be read,
-a zero status is returned;
-otherwise, a nonzero status is returned.
-If target_db contains NULL,
-<function>XrmCombineFileDatabase</function>
-creates and returns a new database to it.
-Otherwise, the database pointed to by target_db is not destroyed by the merge.
-The database entries are merged without changing values or types,
-regardless of the locale of the database.
-The locale of the target database is not modified.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To merge the contents of one database into another database, use
-<function>XrmCombineDatabase</function>.
-<indexterm significance="preferred"><primary>XrmCombineDatabase</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmCombineDatabase</function></funcdef>
- <paramdef>XrmDatabasesource_db,<parameter> *target_db</parameter></paramdef>
- <paramdef>Bool<parameter> override</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>source_db</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database that is to be merged into the target database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>target_db</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database into which the source
-database is to be merged.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>override</emphasis>
- </term>
- <listitem>
- <para>
-Specifies whether source entries override target ones.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmCombineDatabase</function>
-function merges the contents of one database into another.
-If the same specifier is used for an entry in both databases,
-the entry in the source_db will replace the entry in the target_db
-if override is
-<symbol>True</symbol>;
-otherwise, the entry in source_db is discarded.
-If target_db contains NULL,
-<function>XrmCombineDatabase</function>
-simply stores source_db in it.
-Otherwise, source_db is destroyed by the merge, but the database pointed
-to by target_db is not destroyed.
-The database entries are merged without changing values or types,
-regardless of the locales of the databases.
-The locale of the target database is not modified.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To merge the contents of one database into another database with override
-semantics, use
-<function>XrmMergeDatabases</function>.
-<indexterm significance="preferred"><primary>XrmMergeDatabases</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmMergeDatabases</function></funcdef>
- <paramdef>XrmDatabasesource_db,<parameter> *target_db</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>source_db</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database that is to be merged into the target database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>target_db</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database into which the source
-database is to be merged.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Calling the
-<function>XrmMergeDatabases</function>
-function is equivalent to calling the
-<function>XrmCombineDatabase</function>
-function with an override argument of
-<symbol>True</symbol>.
-</para>
-</sect1>
-<sect1 id="Looking_Up_Resources">
-<title>Looking Up Resources</title>
-<!-- .XS -->
-<!-- (SN Looking Up Resources -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To retrieve a resource from a resource database, use
-<function>XrmGetResource</function>,
-<function>XrmQGetResource</function>,
-or
-<function>XrmQGetSearchResource</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-<indexterm significance="preferred"><primary>XrmGetResource</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XrmGetResource</function></funcdef>
- <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
- <paramdef>char<parameter> *str_name</parameter></paramdef>
- <paramdef>char<parameter> *str_class</parameter></paramdef>
- <paramdef>char<parameter> **str_type_return</parameter></paramdef>
- <paramdef>XrmValue<parameter> *value_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the database that is to be used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>str_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the fully qualified name of the value being retrieved (as a string).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>str_class</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the fully qualified class of the value being retrieved (as a string).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>str_type_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the representation type of the destination (as a string).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the value in the database.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-<indexterm significance="preferred"><primary>XrmQGetResource</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XrmQGetResource</function></funcdef>
- <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
- <paramdef>XrmNameList<parameter> quark_name</parameter></paramdef>
- <paramdef>XrmClassList<parameter> quark_class</parameter></paramdef>
- <paramdef>XrmRepresentation<parameter> *quark_type_return</parameter></paramdef>
- <paramdef>XrmValue<parameter> *value_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the database that is to be used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>quark_name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the fully qualified name of the value being retrieved (as a quark).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>quark_class</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the fully qualified class of the value being retrieved (as a quark).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>quark_type_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the representation type of the destination (as a quark).
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the value in the database.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmGetResource</function>
-and
-<function>XrmQGetResource</function>
-functions retrieve a resource from the specified database.
-Both take a fully qualified name/class pair, a destination
-resource representation, and the address of a value
-(size/address pair).
-The value and returned type point into database memory;
-therefore, you must not modify the data.
-</para>
-<para>
-<!-- .LP -->
-The database only frees or overwrites entries on
-<function>XrmPutResource</function>,
-<function>XrmQPutResource</function>,
-or
-<function>XrmMergeDatabases</function>.
-A client that is not storing new values into the database or
-is not merging the database should be safe using the address passed
-back at any time until it exits.
-If a resource was found, both
-<function>XrmGetResource</function>
-and
-<function>XrmQGetResource</function>
-return
-<symbol>True</symbol>;
-otherwise, they return
-<symbol>False</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-Most applications and toolkits do not make random probes
-into a resource database to fetch resources.
-The X toolkit access pattern for a resource database is quite stylized.
-A series of from 1 to 20 probes is made with only the
-last name/class differing in each probe.
-The
-<function>XrmGetResource</function>
-function is at worst a
-2<superscript><emphasis remap='I'>n</emphasis></superscript> algorithm,
-where <emphasis remap='I'>n</emphasis> is the length of the name/class list.
-This can be improved upon by the application programmer by prefetching a list
-of database levels that might match the first part of a name/class list.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain a list of database levels, use
-<function>XrmQGetSearchList</function>.
-<indexterm significance="preferred"><primary>XrmQGetSearchList</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XrmQGetSearchResource</function></funcdef>
- <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
- <paramdef>XrmNameList<parameter> names</parameter></paramdef>
- <paramdef>XrmClassList<parameter> classes</parameter></paramdef>
- <paramdef>XrmSearchList<parameter> list_return</parameter></paramdef>
- <paramdef>int<parameter> list_length</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the database that is to be used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>names</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a list of resource names.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>classes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a list of resource classes.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>list_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns a search list for further use.
-The caller must allocate sufficient space for the list before calling
-<function>XrmQGetSearchList</function>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>list_length</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of entries (not the byte size) allocated for list_return.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmQGetSearchList</function>
-function takes a list of names and classes
-and returns a list of database levels where a match might occur.
-The returned list is in best-to-worst order and
-uses the same algorithm as
-<function>XrmGetResource</function>
-for determining precedence.
-If list_return was large enough for the search list,
-<function>XrmQGetSearchList</function>
-returns
-<symbol>True</symbol>;
-otherwise, it returns
-<symbol>False</symbol>.
-</para>
-<para>
-<!-- .LP -->
-The size of the search list that the caller must allocate is
-dependent upon the number of levels and wildcards in the resource specifiers
-that are stored in the database.
-The worst case length is
-3<superscript><emphasis remap='I'>n</emphasis></superscript>,
-where <emphasis remap='I'>n</emphasis> is the number of name or class
-components in names or classes.
-</para>
-<para>
-<!-- .LP -->
-When using
-<function>XrmQGetSearchList</function>
-followed by multiple probes for resources with a common name and class prefix,
-only the common prefix should be specified in the name and class list to
-<function>XrmQGetSearchList</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To search resource database levels for a given resource, use
-<function>XrmQGetSearchResource</function>.
-<indexterm significance="preferred"><primary>XrmQGetSearchResource</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XrmQGetSearchResource</function></funcdef>
- <paramdef>XrmSearchList<parameter> list</parameter></paramdef>
- <paramdef>XrmName<parameter> name</parameter></paramdef>
- <paramdef>XrmClass<parameter> class</parameter></paramdef>
- <paramdef>XrmRepresentation<parameter> *type_return</parameter></paramdef>
- <paramdef>XrmValue<parameter> *value_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the search list returned by
-<function>XrmQGetSearchList</function>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource name.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>class</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource class.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>type_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns data representation type.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the value in the database.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmQGetSearchResource</function>
-function searches the specified database levels for the resource
-that is fully identified by the specified name and class.
-The search stops with the first match.
-<function>XrmQGetSearchResource</function>
-returns
-<symbol>True</symbol>
-if the resource was found;
-otherwise, it returns
-<symbol>False</symbol>.
-</para>
-<para>
-<!-- .LP -->
-A call to
-<function>XrmQGetSearchList</function>
-with a name and class list containing all but the last component
-of a resource name followed by a call to
-<function>XrmQGetSearchResource</function>
-with the last component name and class returns the same database entry as
-<function>XrmGetResource</function>
-and
-<function>XrmQGetResource</function>
-with the fully qualified name and class.
-</para>
-</sect1>
-<sect1 id="Storing_into_a_Resource_Database">
-<title>Storing into a Resource Database</title>
-<!-- .XS -->
-<!-- (SN Storing into a Resource Database -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To store resources into the database, use
-<function>XrmPutResource</function>
-or
-<function>XrmQPutResource</function>.
-Both functions take a partial resource specification, a
-representation type, and a value.
-This value is copied into the specified database.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-<indexterm significance="preferred"><primary>XrmPutResource</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmPutResource</function></funcdef>
- <paramdef>XrmDatabase<parameter> *database</parameter></paramdef>
- <paramdef>char<parameter> *specifier</parameter></paramdef>
- <paramdef>char<parameter> *type</parameter></paramdef>
- <paramdef>XrmValue<parameter> *value</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>specifier</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a complete or partial specification of the resource.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>type</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the type of the resource.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the value of the resource, which is specified as a string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If database contains NULL,
-<function>XrmPutResource</function>
-creates a new database and returns a pointer to it.
-<function>XrmPutResource</function>
-is a convenience function that calls
-<function>XrmStringToBindingQuarkList</function>
-followed by:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-XrmQPutResource(database, bindings, quarks, XrmStringToQuark(type), value)
-</literallayout>
-If the specifier and type are not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-The value is stored in the database without modification.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-<indexterm significance="preferred"><primary>XrmQPutResource</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmQPutResource</function></funcdef>
- <paramdef>XrmDatabase<parameter> *database</parameter></paramdef>
- <paramdef>XrmBindingList<parameter> bindings</parameter></paramdef>
- <paramdef>XrmQuarkList<parameter> quarks</parameter></paramdef>
- <paramdef>XrmRepresentation<parameter> type</parameter></paramdef>
- <paramdef>XrmValue<parameter> *value</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bindings</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a list of bindings.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>quarks</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the complete or partial name or the class list of the resource.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>type</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the type of the resource.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the value of the resource, which is specified as a string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If database contains NULL,
-<function>XrmQPutResource</function>
-creates a new database and returns a pointer to it.
-If a resource entry with the identical bindings and quarks already
-exists in the database, the previous type and value are replaced by the new
-specified type and value.
-The value is stored in the database without modification.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To add a resource that is specified as a string, use
-<function>XrmPutStringResource</function>.
-<indexterm significance="preferred"><primary>XrmPutStringResource</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmPutStringResource</function></funcdef>
- <paramdef>XrmDatabase<parameter> *database</parameter></paramdef>
- <paramdef>char<parameter> *specifier</parameter></paramdef>
- <paramdef>char<parameter> *value</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>specifier</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a complete or partial specification of the resource.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the value of the resource, which is specified as a string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If database contains NULL,
-<function>XrmPutStringResource</function>
-creates a new database and returns a pointer to it.
-<function>XrmPutStringResource</function>
-adds a resource with the specified value to the specified database.
-<function>XrmPutStringResource</function>
-is a convenience function that first calls
-<function>XrmStringToBindingQuarkList</function>
-on the specifier and then calls
-<function>XrmQPutResource</function>,
-using a ``String'' representation type.
-If the specifier is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-The value is stored in the database without modification.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To add a string resource using quarks as a specification, use
-<function>XrmQPutStringResource</function>.
-<indexterm significance="preferred"><primary>XrmQPutStringResource</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmQPutStringResource</function></funcdef>
- <paramdef>XrmDatabase<parameter> *database</parameter></paramdef>
- <paramdef>XrmBindingList<parameter> bindings</parameter></paramdef>
- <paramdef>XrmQuarkList<parameter> quarks</parameter></paramdef>
- <paramdef>char<parameter> *value</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bindings</emphasis>
- </term>
- <listitem>
- <para>
-Specifies a list of bindings.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>quarks</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the complete or partial name or the class list of the resource.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the value of the resource, which is specified as a string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If database contains NULL,
-<function>XrmQPutStringResource</function>
-creates a new database and returns a pointer to it.
-<function>XrmQPutStringResource</function>
-is a convenience routine that constructs an
-<type>XrmValue</type>
-for the value string (by calling
-<function>strlen</function>
-to compute the size) and
-then calls
-<function>XrmQPutResource</function>,
-using a ``String'' representation type.
-The value is stored in the database without modification.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To add a single resource entry that is specified as a string that contains
-both a name and a value, use
-<function>XrmPutLineResource</function>.
-<indexterm significance="preferred"><primary>XrmPutLineResource</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmPutLineResource</function></funcdef>
- <paramdef>XrmDatabase<parameter> *database</parameter></paramdef>
- <paramdef>char<parameter> *line</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>line</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource name and value pair as a single string.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If database contains NULL,
-<function>XrmPutLineResource</function>
-creates a new database and returns a pointer to it.
-<function>XrmPutLineResource</function>
-adds a single resource entry to the specified database.
-The line should be in valid ResourceLine format (see section 15.1)
-terminated by a newline or null character;
-the database that results from using a string
-with incorrect syntax is implementation-dependent.
-The string is parsed in the locale of the database.
-If the
-<replaceable>ResourceName</replaceable>
-is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-Note that comment lines are not stored.
-</para>
-</sect1>
-<sect1 id="Enumerating_Database_Entries">
-<title>Enumerating Database Entries</title>
-<!-- .XS -->
-<!-- (SN Enumerating Database Entries -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To enumerate the entries of a database, use
-<function>XrmEnumerateDatabase</function>.
-<indexterm significance="preferred"><primary>XrmEnumerateDatabase</primary></indexterm>
-<!-- .sM -->
-</para>
-
-<literallayout class="monospaced">
-#define XrmEnumAllLevels 0
-#define XrmEnumOneLevel 0
-</literallayout>
-
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XrmEnumerateDatabase</function></funcdef>
- <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
- <paramdef>XrmNameList<parameter> name_prefix</parameter></paramdef>
- <paramdef>XrmClassList<parameter> class_prefix</parameter></paramdef>
- <paramdef>int<parameter> mode</parameter></paramdef>
- <paramdef>Bool<parameter> (*proc)()</parameter></paramdef>
- <paramdef>XPointer<parameter> arg</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>name_prefix</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource name prefix.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>class_prefix</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource class prefix.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>mode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of levels to enumerate.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>proc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the procedure that is to be called for each matching entry.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>arg</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the user-supplied argument that will be passed to the procedure.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmEnumerateDatabase</function>
-function calls the specified procedure for each resource in the database
-that would match some completion of the given name/class resource prefix.
-The order in which resources are found is implementation-dependent.
-If mode is
-<symbol>XrmEnumOneLevel</symbol>,
-a resource must match the given name/class prefix with
-just a single name and class appended. If mode is
-<symbol>XrmEnumAllLevels</symbol>,
-the resource must match the given name/class prefix with one or more names and
-classes appended.
-If the procedure returns
-<symbol>True</symbol>,
-the enumeration terminates and the function returns
-<symbol>True</symbol>.
-If the procedure always returns
-<symbol>False</symbol>,
-all matching resources are enumerated and the function returns
-<symbol>False</symbol>.
-</para>
-<para>
-<!-- .LP -->
-The procedure is called with the following arguments:
-</para>
-<para>
-<!-- .LP -->
-<!-- .\" Start marker code here -->
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-(*<emphasis remap='I'>proc</emphasis>)(<emphasis remap='I'>database</emphasis>, <emphasis remap='I'>bindings</emphasis>, <emphasis remap='I'>quarks</emphasis>, <emphasis remap='I'>type</emphasis>, <emphasis remap='I'>value</emphasis>, <emphasis remap='I'>arg</emphasis>)
- XrmDatabase *<emphasis remap='I'>database</emphasis>;
- XrmBindingList <emphasis remap='I'>bindings</emphasis>;
- XrmQuarkList <emphasis remap='I'>quarks</emphasis>;
- XrmRepresentation *<emphasis remap='I'>type</emphasis>;
- XrmValue *<emphasis remap='I'>value</emphasis>;
- XPointer <emphasis remap='I'>arg</emphasis>;
-</literallayout>
-<!-- .\" End marker code here -->
-</para>
-<para>
-<!-- .LP -->
-The bindings and quarks lists are terminated by
-<symbol>NULLQUARK</symbol>.
-Note that pointers
-to the database and type are passed, but these values should not be modified.
-</para>
-<para>
-<!-- .LP -->
-The procedure must not modify the database.
-If Xlib has been initialized for threads, the procedure is called with
-the database locked and the result of a call by the procedure to any
-Xlib function using the same database is not defined.
-</para>
-</sect1>
-<sect1 id="Parsing_Command_Line_Options">
-<title>Parsing Command Line Options</title>
-<!-- .XS -->
-<!-- (SN Parsing Command Line Options -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The
-<function>XrmParseCommand</function>
-function can be used to parse the command line arguments to a program
-and modify a resource database with selected entries from the command line.
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XrmOptionKind</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef enum {
- XrmoptionNoArg, /* Value is specified in XrmOptionDescRec.value */
- XrmoptionIsArg, /* Value is the option string itself */
- XrmoptionStickyArg, /* Value is characters immediately following option */
- XrmoptionSepArg, /* Value is next argument in argv */
- XrmoptionResArg, /* Resource and value in next argument in argv */
- XrmoptionSkipArg, /* Ignore this option and the next argument in argv */
- XrmoptionSkipLine, /* Ignore this option and the rest of argv */
- XrmoptionSkipNArgs /* Ignore this option and the next
- \ \ \ XrmOptionDescRec.value arguments in argv */
-} XrmOptionKind;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Note that
-<constant>XrmoptionSkipArg</constant>
-is equivalent to
-<constant>XrmoptionSkipNArgs</constant>
-with the
-<structname>XrmOptionDescRec</structname>.<structfield>value</structfield>
-field containing the value one.
-Note also that the value zero for
-<constant>XrmoptionSkipNArgs</constant>
-indicates that only the option itself is to be skipped.
-</para>
-<para>
-<!-- .LP -->
-<indexterm significance="preferred"><primary>XrmOptionDescRec</primary></indexterm>
-<!-- .sM -->
-<literallayout class="monospaced">
-<!-- .TA .5i 2.5i -->
-<!-- .ta .5i 2.5i -->
-typedef struct {
- char *option; /* Option specification string in argv */
- char *specifier; /* Binding and resource name (sans application name) */
- XrmOptionKind argKind; /* Which style of option it is */
- XPointer value; /* Value to provide if XrmoptionNoArg or
- \ \ \ XrmoptionSkipNArgs */
-} XrmOptionDescRec, *XrmOptionDescList;
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To load a resource database from a C command line, use
-<function>XrmParseCommand</function>.
-<indexterm significance="preferred"><primary>XrmParseCommand</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XrmParseCommand</function></funcdef>
- <paramdef>XrmDatabase<parameter> *database</parameter></paramdef>
- <paramdef>XrmOptionDescList<parameter> table</parameter></paramdef>
- <paramdef>int<parameter> table_count</parameter></paramdef>
- <paramdef>char<parameter> *name</parameter></paramdef>
- <paramdef>int<parameter> *argc_in_out</parameter></paramdef>
- <paramdef>char<parameter> **argv_in_out</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>database</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource database.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>table</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the table of command line arguments to be parsed.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>table_count</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of entries in the table.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>name</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the application name.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>argc_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of arguments and returns the number of remaining arguments.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>argv_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the command line arguments
-and returns the remaining arguments.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XrmParseCommand</function>
-function parses an (argc, argv) pair according to the specified option table,
-loads recognized options into the specified database with type ``String,''
-and modifies the (argc, argv) pair to remove all recognized options.
-If database contains NULL,
-<function>XrmParseCommand</function>
-creates a new database and returns a pointer to it.
-Otherwise, entries are added to the database specified.
-If a database is created, it is created in the current locale.
-</para>
-<para>
-<!-- .LP -->
-The specified table is used to parse the command line.
-Recognized options in the table are removed from argv,
-and entries are added to the specified resource database
-in the order they occur in argv.
-The table entries contain information on the option string,
-the option name, the style of option,
-and a value to provide if the option kind is
-<constant>XrmoptionNoArg</constant>.
-The option names are compared byte-for-byte to arguments in argv,
-independent of any locale.
-The resource values given in the table are stored in the resource database
-without modification.
-All resource database entries are created
-using a ``String'' representation type.
-The argc argument specifies the number of arguments in argv
-and is set on return to the remaining number of arguments that were not parsed.
-The name argument should be the name of your application
-for use in building the database entry.
-The name argument is prefixed to the resourceName in the option table
-before storing a database entry.
-The name argument is treated as a single component, even if it
-has embedded periods.
-No separating (binding) character is inserted,
-so the table must contain either a period (.) or an asterisk (*)
-as the first character in each resourceName entry.
-To specify a more completely qualified resource name,
-the resourceName entry can contain multiple components.
-If the name argument and the resourceNames are not in the
-Host Portable Character Encoding,
-the result is implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-The following provides a sample option table:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-<!-- .TA 1.25i 3.25i 4.75i -->
-<!-- .ta 1.25i 3.25i 4.75i -->
-static XrmOptionDescRec opTable[] = {
-{"-background", "*background", XrmoptionSepArg, (XPointer) NULL},
-{"-bd", "*borderColor", XrmoptionSepArg, (XPointer) NULL},
-{"-bg", "*background", XrmoptionSepArg, (XPointer) NULL},
-{"-borderwidth", "*TopLevelShell.borderWidth", XrmoptionSepArg, (XPointer) NULL},
-{"-bordercolor", "*borderColor", XrmoptionSepArg, (XPointer) NULL},
-{"-bw", "*TopLevelShell.borderWidth", XrmoptionSepArg, (XPointer) NULL},
-{"-display", ".display", XrmoptionSepArg, (XPointer) NULL},
-{"-fg", "*foreground", XrmoptionSepArg, (XPointer) NULL},
-{"-fn", "*font", XrmoptionSepArg, (XPointer) NULL},
-{"-font", "*font", XrmoptionSepArg, (XPointer) NULL},
-{"-foreground", "*foreground", XrmoptionSepArg, (XPointer) NULL},
-{"-geometry", ".TopLevelShell.geometry", XrmoptionSepArg, (XPointer) NULL},
-{"-iconic", ".TopLevelShell.iconic", XrmoptionNoArg, (XPointer) "on"},
-{"-name", ".name", XrmoptionSepArg, (XPointer) NULL},
-{"-reverse", "*reverseVideo", XrmoptionNoArg, (XPointer) "on"},
-{"-rv", "*reverseVideo", XrmoptionNoArg, (XPointer) "on"},
-{"-synchronous", "*synchronous", XrmoptionNoArg, (XPointer) "on"},
-{"-title", ".TopLevelShell.title", XrmoptionSepArg, (XPointer) NULL},
-{"-xrm", NULL, XrmoptionResArg, (XPointer) NULL},
-};
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-In this table, if the -background (or -bg) option is used to set
-background colors, the stored resource specifier matches all
-resources of attribute background.
-If the -borderwidth option is used,
-the stored resource specifier applies only to border width
-attributes of class TopLevelShell (that is, outer-most windows, including
-pop-up windows).
-If the -title option is used to set a window name,
-only the topmost application windows receive the resource.
-</para>
-<para>
-<!-- .LP -->
-When parsing the command line,
-any unique unambiguous abbreviation for an option name in the table is
-considered a match for the option.
-Note that uppercase and lowercase matter.
-<!-- .bp -->
-
-</para>
-</sect1>
-</chapter>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<chapter id="resource_manager_functions">
+<title>Resource Manager Functions</title>
+<!-- .sp 2 -->
+<!-- .nr H1 15 -->
+<!-- .nr H2 0 -->
+<!-- .nr H3 0 -->
+<!-- .nr H4 0 -->
+<!-- .nr H5 0 -->
+<!-- .na -->
+<para>
+<!-- .LP -->
+<!-- .XS -->
+<!-- Chapter 15: Resource Manager Functions -->
+<!-- .XE -->
+A program often needs a variety of options in the X environment
+(for example, fonts, colors, icons, and cursors).
+Specifying all of these options on the command line is awkward
+because users may want to customize many aspects of the program
+and need a convenient way to establish these customizations as
+the default settings.
+The resource manager is provided for this purpose.
+Resource specifications are usually stored in human-readable files
+and in server properties.
+</para>
+<para>
+<!-- .LP -->
+The resource manager is a database manager with a twist.
+In most database systems,
+you perform a query using an imprecise specification,
+and you get back a set of records.
+The resource manager, however, allows you to specify a large
+set of values with an imprecise specification, to query the database
+with a precise specification, and to get back only a single value.
+This should be used by applications that need to know what the
+user prefers for colors, fonts, and other resources.
+It is this use as a database for dealing with X resources that
+inspired the name "Resource Manager,"
+although the resource manager can be and is used in other ways.
+</para>
+<para>
+<!-- .LP -->
+For example,
+a user of your application may want to specify
+that all windows should have a blue background
+but that all mail-reading windows should have a red background.
+With well-engineered and coordinated applications,
+a user can define this information using only two lines of specifications.
+</para>
+<para>
+<!-- .LP -->
+As an example of how the resource manager works,
+consider a mail-reading application called xmh.
+Assume that it is designed so that it uses a
+complex window hierarchy all the way down to individual command buttons,
+which may be actual small subwindows in some toolkits.
+These are often called objects or widgets.
+In such toolkit systems,
+each user interface object can be composed of other objects
+and can be assigned a name and a class.
+Fully qualified names or classes can have arbitrary numbers of component names,
+but a fully qualified name always has the same number of component names as a
+fully qualified class.
+This generally reflects the structure of the application as composed
+of these objects, starting with the application itself.
+</para>
+<para>
+<!-- .LP -->
+For example, the xmh mail program has a name "xmh" and is one
+of a class of "Mail" programs.
+By convention, the first character of class components is capitalized,
+and the first letter of name components is in lowercase.
+Each name and class finally has an attribute
+(for example, "foreground" or "font").
+If each window is properly assigned a name and class,
+it is easy for the user to specify attributes of any portion
+of the application.
+</para>
+<para>
+<!-- .LP -->
+At the top level,
+the application might consist of a paned window (that is, a window divided
+into several sections) named "toc".
+One pane of the paned window is a button box window named "buttons"
+and is filled with command buttons.
+One of these command buttons is used to incorporate
+new mail and has the name "incorporate".
+This window has a fully qualified name, "xmh.toc.buttons.incorporate",
+and a fully qualified class, "Xmh.Paned.Box.Command".
+Its fully qualified name is the name of its parent, "xmh.toc.buttons",
+followed by its name, "incorporate".
+Its class is the class of its parent, "Xmh.Paned.Box",
+followed by its particular class, "Command".
+The fully qualified name of a resource is
+the attribute's name appended to the object's fully qualified
+name, and the fully qualified class is its class appended to the object's
+class.
+</para>
+<para>
+<!-- .LP -->
+The incorporate button might need the following resources:
+Title string,
+Font,
+Foreground color for its inactive state,
+Background color for its inactive state,
+Foreground color for its active state, and
+Background color for its active state.
+Each resource is considered
+to be an attribute of the button and, as such, has a name and a class.
+For example, the foreground color for the button in
+its active state might be named "activeForeground",
+and its class might be "Foreground".
+</para>
+<para>
+<!-- .LP -->
+When an application looks up a resource (for example, a color),
+it passes the complete name and complete class of the resource
+to a look-up routine.
+The resource manager compares this complete specification
+against the incomplete specifications of entries in the resource
+database, finds the best match, and returns the corresponding
+value for that entry.
+</para>
+<para>
+<!-- .LP -->
+The definitions for the resource manager are contained in
+<filename class="headerfile">&lt;X11/Xresource.h&gt;</filename>.
+<indexterm type="file"><primary><filename class="headerfile">X11/Xresource.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xresource.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xresource.h&gt;</filename></secondary></indexterm>
+</para>
+<sect1 id="Resource_File_Syntax">
+<title>Resource File Syntax</title>
+<!-- .XS -->
+<!-- (SN Resource File Syntax -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The syntax of a resource file is a sequence of resource lines
+terminated by newline characters or the end of the file.
+The syntax of an individual resource line is:
+</para>
+<para>
+<!-- .LP -->
+<!-- .\" Start marker code here -->
+<literallayout class="monospaced">
+<!-- .TA 1.5i 1.75i -->
+<!-- .ta 1.5i 1.75i -->
+ResourceLine = Comment | IncludeFile | ResourceSpec | &lt;empty line&gt;
+Comment = "!" {&lt;any character except null or newline&gt;}
+IncludeFile = "#" WhiteSpace "include" WhiteSpace FileName WhiteSpace
+FileName = &lt;valid filename for operating system&gt;
+ResourceSpec = WhiteSpace ResourceName WhiteSpace ":" WhiteSpace Value
+ResourceName = [Binding] {Component Binding} ComponentName
+Binding = "." | "*"
+WhiteSpace = {&lt;space&gt; | &lt;horizontal tab&gt;}
+Component = "?" | ComponentName
+ComponentName = NameChar {NameChar}
+NameChar = "a"-"z" | "A"-"Z" | "0"-"9" | "_" | "-"
+Value = {&lt;any character except null or unescaped newline&gt;}
+</literallayout>
+<!-- .\" End marker code here -->
+</para>
+<para>
+<!-- .LP -->
+Elements separated by vertical bar (|) are alternatives.
+Curly braces ({......}) indicate zero or more repetitions
+of the enclosed elements.
+Square brackets ([......]) indicate that the enclosed element is optional.
+Quotes ("......") are used around literal characters.
+</para>
+<para>
+<!-- .LP -->
+IncludeFile lines are interpreted by replacing the line with the
+contents of the specified file.
+The word "include" must be in lowercase.
+The file name is interpreted relative to the directory of the file in
+which the line occurs (for example, if the file name contains no
+directory or contains a relative directory specification).
+</para>
+<para>
+<!-- .LP -->
+If a ResourceName contains a contiguous sequence of two or more Binding
+characters, the sequence will be replaced with a single ".." character
+if the sequence contains only ".." characters;
+otherwise, the sequence will be replaced with a single "*" character.
+</para>
+<para>
+<!-- .LP -->
+A resource database never contains more than one entry for a given
+ResourceName. If a resource file contains multiple lines with the
+same ResourceName, the last line in the file is used.
+</para>
+<para>
+<!-- .LP -->
+Any white space characters before or after the name or colon in a ResourceSpec
+are ignored.
+To allow a Value to begin with white space,
+the two-character sequence "\\<emphasis remap='I'>space</emphasis>" (backslash followed by space)
+is recognized and replaced by a space character,
+and the two-character sequence "\\<emphasis remap='I'>tab</emphasis>"
+(backslash followed by horizontal tab)
+is recognized and replaced by a horizontal tab character.
+To allow a Value to contain embedded newline characters,
+the two-character sequence "\\n" is recognized and replaced by a
+newline character.
+To allow a Value to be broken across multiple lines in a text file,
+the two-character sequence "\\<emphasis remap='I'>newline</emphasis>"
+(backslash followed by newline) is
+recognized and removed from the value.
+To allow a Value to contain arbitrary character codes,
+the four-character sequence "\\<emphasis remap='I'>nnn</emphasis>",
+where each <emphasis remap='I'>n</emphasis> is a digit character in the range of "0"-"7",
+is recognized and replaced with a single byte that contains
+the octal value specified by the sequence.
+Finally, the two-character sequence "\newline" is recognized
+and replaced with a single backslash.
+</para>
+<para>
+<!-- .LP -->
+As an example of these sequences,
+the following resource line contains a value consisting of four
+characters: a backslash, a null, a "z", and a newline:
+<literallayout class="monospaced">
+magic.values: \\000\
+z\n
+</literallayout>
+</para>
+</sect1>
+<sect1 id="Resource_Manager_Matching_Rules">
+<title>Resource Manager Matching Rules</title>
+<!-- .XS -->
+<!-- (SN Resource Manager Matching Rules -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The algorithm for determining which resource database entry
+matches a given query is the heart of the resource manager.
+All queries must fully specify the name and class of the desired resource
+(use of the characters "*" and "?" is not permitted).
+The library supports up to 100 components in a full name or class.
+Resources are stored in the database with only partially specified
+names and classes, using pattern matching constructs.
+An asterisk (*) is a loose binding and is used to represent any number
+of intervening components, including none.
+A period (.) is a tight binding and is used to separate immediately
+adjacent components.
+A question mark (?) is used to match any single component name or class.
+A database entry cannot end in a loose binding;
+the final component (which cannot be the character "?") must be specified.
+The lookup algorithm searches the database for the entry that most
+closely matches (is most specific for) the full name and class being queried.
+When more than one database entry matches the full name and class,
+precedence rules are used to select just one.
+</para>
+<para>
+<!-- .LP -->
+The full name and class are scanned from left to right (from highest
+level in the hierarchy to lowest), one component at a time.
+At each level, the corresponding component and/or binding of each
+matching entry is determined, and these matching components and
+bindings are compared according to precedence rules.
+Each of the rules is applied at each level before moving to the next level,
+until a rule selects a single entry over all others.
+The rules, in order of precedence, are:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+An entry that contains a matching component (whether name, class,
+or the character "?")
+takes precedence over entries that elide the level (that is, entries
+that match the level in a loose binding).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+An entry with a matching name takes precedence over both
+entries with a matching class and entries that match using the character "?".
+An entry with a matching class takes precedence over
+entries that match using the character "?".
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+An entry preceded by a tight binding takes precedence over entries
+preceded by a loose binding.
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+To illustrate these rules,
+consider the following resource database entries:
+<literallayout class="monospaced">
+<!-- .TA 2.5i 3.5i -->
+<!-- .ta 2.5i 3.5i -->
+xmh*Paned*activeForeground: red <emphasis remap='I'>(entry A)</emphasis>
+*incorporate.Foreground: blue <emphasis remap='I'>(entry B)</emphasis>
+xmh.toc*Command*activeForeground: green <emphasis remap='I'>(entry C)</emphasis>
+xmh.toc*?.Foreground: white <emphasis remap='I'>(entry D)</emphasis>
+xmh.toc*Command.activeForeground: black <emphasis remap='I'>(entry E)</emphasis>
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+Consider a query for the resource:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA 3.5i -->
+<!-- .ta 3.5i -->
+xmh.toc.messagefunctions.incorporate.activeForeground <emphasis remap='I'>(name)</emphasis>
+Xmh.Paned.Box.Command.Foreground <emphasis remap='I'>(class)</emphasis>
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+At the first level (xmh, Xmh), rule 1 eliminates entry B.
+At the second level (toc, Paned), rule 2 eliminates entry A.
+At the third level (messagefunctions, Box), no entries are eliminated.
+At the fourth level (incorporate, Command), rule 2 eliminates entry D.
+At the fifth level (activeForeground, Foreground), rule 3 eliminates entry C.
+</para>
+</sect1>
+<sect1 id="Quarks">
+<title>Quarks</title>
+<!-- .XS -->
+<!-- (SN Quarks -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Most uses of the resource manager involve defining names,
+classes, and representation types as string constants.
+However, always referring to strings in the resource manager can be slow,
+because it is so heavily used in some toolkits.
+To solve this problem,
+a shorthand for a string is used in place of the string
+in many of the resource manager functions.
+Simple comparisons can be performed rather than string comparisons.
+The shorthand name for a string is called a quark and is the
+type
+<type>XrmQuark</type>.
+On some occasions,
+you may want to allocate a quark that has no string equivalent.
+</para>
+<para>
+<!-- .LP -->
+A quark is to a string what an atom is to a string in the server,
+but its use is entirely local to your application.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To allocate a new quark, use
+<function>XrmUniqueQuark</function>.
+</para>
+<indexterm significance="preferred"><primary>XrmUniqueQuark</primary></indexterm>
+<!-- .sM -->
+<para>XrmQuark XrmUniqueQuark()</para>
+<!-- .FN -->
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmUniqueQuark</function>
+function allocates a quark that is guaranteed not to represent any string that
+is known to the resource manager.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+Each name, class, and representation type is typedef'd as an
+<type>XrmQuark</type>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<literallayout class="monospaced">
+typedef int XrmQuark, *XrmQuarkList;
+typedef XrmQuark XrmName;
+typedef XrmQuark XrmClass;
+typedef XrmQuark XrmRepresentation;
+#define NULLQUARK ((XrmQuark) 0)
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Lists are represented as null-terminated arrays of quarks.
+The size of the array must be large enough for the number of components used.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<literallayout class="monospaced">
+typedef XrmQuarkList XrmNameList;
+typedef XrmQuarkList XrmClassList;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To convert a string to a quark, use
+<function>XrmStringToQuark</function>
+or
+<function>XrmPermStringToQuark</function>.
+</para>
+<literallayout class="monospaced">
+#define XrmStringToName(string) XrmStringToQuark(string)
+#define XrmStringToClass(string) XrmStringToQuark(string)
+#define XrmStringToRepresentation(string) XrmStringToQuark(string)
+</literallayout>
+
+<indexterm significance="preferred"><primary>XrmStringToQuark</primary></indexterm>
+<indexterm significance="preferred"><primary>XrmPermStringToQuark</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmstringtoquark'>
+<funcprototype>
+ <funcdef>XrmQuark <function>XrmStringToQuark</function></funcdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<!-- .ds Ql -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the string for which a quark(Ql is to be allocated.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+These functions can be used to convert from string to quark representation.
+If the string is not in the Host Portable Character Encoding,
+the conversion is implementation-dependent.
+The string argument to
+<function>XrmStringToQuark</function>
+need not be permanently allocated storage.
+<function>XrmPermStringToQuark</function>
+is just like
+<function>XrmStringToQuark</function>,
+except that Xlib is permitted to assume the string argument is permanently
+allocated,
+and, hence, that it can be used as the value to be returned by
+<function>XrmQuarkToString</function>.
+</para>
+<para>
+<!-- .LP -->
+For any given quark, if
+<function>XrmStringToQuark</function>
+returns a non-NULL value,
+all future calls will return the same value (identical address).
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To convert a quark to a string, use
+<function>XrmQuarkToString</function>.
+</para>
+
+<literallayout class="monospaced">
+#define XrmNameToString(name) XrmQuarkToString(name)
+#define XrmClassToString(class) XrmQuarkToString(name)
+#define XrmRepresentationToString(type) XrmQuarkToString(type)
+</literallayout>
+<indexterm significance="preferred"><primary>XrmQuarkToString</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmquarktostring'>
+<funcprototype>
+ <funcdef>char *<function>XrmQuarkToString</function></funcdef>
+ <paramdef>XrmQuark<parameter> quark</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>quark</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the quark for which the equivalent string is desired.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+<!-- AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA -->
+<para>
+These functions can be used to convert from quark representation to string.
+The string pointed to by the return value must not be modified or freed.
+The returned string is byte-for-byte equal to the original
+string passed to one of the string-to-quark routines.
+If no string exists for that quark,
+<function>XrmQuarkToString</function>
+returns NULL.
+For any given quark, if
+<function>XrmQuarkToString</function>
+returns a non-NULL value,
+all future calls will return the same value (identical address).
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To convert a string with one or more components to a quark list, use
+<function>XrmStringToQuarkList</function>.
+</para>
+
+<literallayout class="monospaced">
+#define XrmStringToNameList(str,name) XrmStringToQuarkList((str), (name))
+#define XrmStringToClassList(str,class) XrmStringToQuarkList((str), (class))
+</literallayout>
+
+<indexterm significance="preferred"><primary>XrmStringToQuarkList</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmstringtoquarklist'>
+<funcprototype>
+ <funcdef>void <function>XrmStringToQuarkList</function></funcdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+ <paramdef>XrmQuarkList<parameter> quarks_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<!-- .ds Ql \ list -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the string for which a quark(Ql is to be allocated.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>quarks_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the list of quarks.
+The caller must allocate sufficient space for the quarks list before calling
+<function>XrmStringToQuarkList</function>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmStringToQuarkList</function>
+function converts the null-terminated string (generally a fully qualified name)
+to a list of quarks.
+Note that the string must be in the valid ResourceName format
+(see section 15.1).
+If the string is not in the Host Portable Character Encoding,
+the conversion is implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+A binding list is a list of type
+<type>XrmBindingList</type>
+and indicates if components of name or class lists are bound tightly or loosely
+(that is, if wildcarding of intermediate components is specified).
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+typedef enum {XrmBindTightly, XrmBindLoosely} XrmBinding, *XrmBindingList;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<constant>XrmBindTightly</constant>
+indicates that a period separates the components, and
+<constant>XrmBindLoosely</constant>
+indicates that an asterisk separates the components.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To convert a string with one or more components to a binding list
+and a quark list, use
+<function>XrmStringToBindingQuarkList</function>.
+<indexterm significance="preferred"><primary>XrmStringToBindingQuarkList</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmstringtobindingquarklist'>
+<funcprototype>
+ <funcdef><function>XrmStringToBindingQuarkList</function></funcdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+ <paramdef>XrmBindingList<parameter> bindings_return</parameter></paramdef>
+ <paramdef>XrmQuarkList<parameter> quarks_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<!-- .ds Ql \ list -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the string for which a quark(Ql is to be allocated.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bindings_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the binding list.
+The caller must allocate sufficient space for the binding list before calling
+<function>XrmStringToBindingQuarkList</function>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>quarks_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the list of quarks.
+The caller must allocate sufficient space for the quarks list before calling
+<function>XrmStringToBindingQuarkList</function>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Component names in the list are separated by a period or
+an asterisk character.
+The string must be in the format of a valid ResourceName (see section 15.1).
+If the string does not start with a period or an asterisk,
+a tight binding is assumed.
+For example, the string ``*a.b*c'' becomes:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA .75i 1.5i 2.25i -->
+<!-- .ta .75i 1.5i 2.25i -->
+quarks: a b c
+bindings: loose tight loose
+</literallayout>
+</para>
+</sect1>
+<sect1 id="Creating_and_Storing_Databases">
+<title>Creating and Storing Databases</title>
+<!-- .XS -->
+<!-- (SN Creating and Storing Databases -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XrmDatabase</primary></indexterm>
+A resource database is an opaque type,
+<type>XrmDatabase</type>.
+Each database value is stored in an
+<type>XrmValue</type>
+structure.
+This structure consists of a size, an address, and a representation type.
+The size is specified in bytes.
+The representation type is a way for you to store data tagged by some
+application-defined type (for example, the strings ``font'' or ``color'').
+It has nothing to do with the C data type or with its class.
+The
+<type>XrmValue</type>
+structure is defined as:
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XrmValue</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+typedef struct {
+ unsigned int size;
+ XPointer addr;
+} XrmValue, *XrmValuePtr;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To initialize the resource manager, use
+<function>XrmInitialize</function>.
+<indexterm significance="preferred"><primary>XrmInitialize</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrminitialize'>
+<funcprototype>
+ <funcdef>void <function>XrmInitialize</function></funcdef>
+ <paramdef>void<parameter> XrmInitialize(\|)</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+To retrieve a database from disk, use
+<function>XrmGetFileDatabase</function>.
+<indexterm significance="preferred"><primary>XrmGetFileDatabase</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmgetfiledatabase'>
+<funcprototype>
+ <funcdef>XrmDatabase <function>XrmGetFileDatabase</function></funcdef>
+ <paramdef>char<parameter> *filename</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>filename</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database file name.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmGetFileDatabase</function>
+function opens the specified file,
+creates a new resource database, and loads it with the specifications
+read in from the specified file.
+The specified file should contain a sequence of entries in valid ResourceLine
+format (see section 15.1); the database that results from reading a file
+with incorrect syntax is implementation-dependent.
+The file is parsed in the current locale,
+and the database is created in the current locale.
+If it cannot open the specified file,
+<function>XrmGetFileDatabase</function>
+returns NULL.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To store a copy of a database to disk, use
+<function>XrmPutFileDatabase</function>.
+<indexterm significance="preferred"><primary>XrmPutFileDatabase</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmputfiledatabase'>
+<funcprototype>
+ <funcdef>void <function>XrmPutFileDatabase</function></funcdef>
+ <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
+ <paramdef>char<parameter> *stored_db</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the database that is to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>stored_db</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the file name for the stored database.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmPutFileDatabase</function>
+function stores a copy of the specified database in the specified file.
+Text is written to the file as a sequence of entries in valid
+ResourceLine format (see section 15.1).
+The file is written in the locale of the database.
+Entries containing resource names that are not in the Host Portable Character
+Encoding or containing values that are not in the encoding of the database
+locale, are written in an implementation-dependent manner.
+The order in which entries are written is implementation-dependent.
+Entries with representation types other than ``String'' are ignored.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain a pointer to the screen-independent resources of a display, use
+<function>XResourceManagerString</function>.
+<indexterm significance="preferred"><primary>XResourceManagerString</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xresourcemanagerstring'>
+<funcprototype>
+ <funcdef>char *<function>XResourceManagerString</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XResourceManagerString</function>
+function returns the RESOURCE_MANAGER property from the server's root
+window of screen zero, which was returned when the connection was opened using
+<function>XOpenDisplay</function>.
+The property is converted from type STRING to the current locale.
+The conversion is identical to that produced by
+<function>XmbTextPropertyToTextList</function>
+for a single element STRING property.
+The returned string is owned by Xlib and should not be freed by the client.
+The property value must be in a format that is acceptable to
+<function>XrmGetStringDatabase</function>.
+If no property exists, NULL is returned.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain a pointer to the screen-specific resources of a screen, use
+<function>XScreenResourceString</function>.
+<indexterm significance="preferred"><primary>XScreenResourceString</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xscreenresourcestring'>
+<funcprototype>
+ <funcdef>char *<function>XScreenResourceString</function></funcdef>
+ <paramdef>Screen<parameter> *screen</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the screen.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XScreenResourceString</function>
+function returns the SCREEN_RESOURCES property from the root window of the
+specified screen.
+The property is converted from type STRING to the current locale.
+The conversion is identical to that produced by
+<function>XmbTextPropertyToTextList</function>
+for a single element STRING property.
+The property value must be in a format that is acceptable to
+<function>XrmGetStringDatabase</function>.
+If no property exists, NULL is returned.
+The caller is responsible for freeing the returned string by using
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create a database from a string, use
+<function>XrmGetStringDatabase</function>.
+<indexterm significance="preferred"><primary>XrmGetStringDatabase</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmgetstringdatabase'>
+<funcprototype>
+ <funcdef>XrmDatabase <function>XrmGetStringDatabase</function></funcdef>
+ <paramdef>char<parameter> *data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the database contents using a string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmGetStringDatabase</function>
+function creates a new database and stores the resources specified
+in the specified null-terminated string.
+<function>XrmGetStringDatabase</function>
+is similar to
+<function>XrmGetFileDatabase</function>
+except that it reads the information out of a string instead of out of a file.
+The string should contain a sequence of entries in valid ResourceLine
+format (see section 15.1) terminated by a null character;
+the database that results from using a string
+with incorrect syntax is implementation-dependent.
+The string is parsed in the current locale,
+and the database is created in the current locale.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the locale name of a database, use
+<function>XrmLocaleOfDatabase</function>.
+<indexterm significance="preferred"><primary>XrmLocaleOfDatabase</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmlocaleofdatabase'>
+<funcprototype>
+ <funcdef>char *<function>XrmLocaleOfDatabase</function></funcdef>
+ <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmLocaleOfDatabase</function>
+function returns the name of the locale bound to the specified
+database, as a null-terminated string.
+The returned locale name string is owned by Xlib and should not be
+modified or freed by the client.
+Xlib is not permitted to free the string until the database is destroyed.
+Until the string is freed,
+it will not be modified by Xlib.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To destroy a resource database and free its allocated memory, use
+<function>XrmDestroyDatabase</function>.
+<indexterm significance="preferred"><primary>XrmDestroyDatabase</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmdestroydatabase'>
+<funcprototype>
+ <funcdef>void <function>XrmDestroyDatabase</function></funcdef>
+ <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If database is NULL,
+<function>XrmDestroyDatabase</function>
+returns immediately.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To associate a resource database with a display, use
+<function>XrmSetDatabase</function>.
+<indexterm significance="preferred"><primary>XrmSetDatabase</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmsetdatabase'>
+<funcprototype>
+ <funcdef>void <function>XrmSetDatabase</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmSetDatabase</function>
+function associates the specified resource database (or NULL)
+with the specified display.
+The database previously associated with the display (if any) is not destroyed.
+A client or toolkit may find this function convenient for retaining a database
+once it is constructed.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To get the resource database associated with a display, use
+<function>XrmGetDatabase</function>.
+<indexterm significance="preferred"><primary>XrmGetDatabase</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmgetdatabase'>
+<funcprototype>
+ <funcdef>XrmDatabase <function>XrmGetDatabase</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmGetDatabase</function>
+function returns the database associated with the specified display.
+It returns NULL if a database has not yet been set.
+</para>
+</sect1>
+<sect1 id="Merging_Resource_Databases">
+<title>Merging Resource Databases</title>
+<!-- .XS -->
+<!-- (SN Merging Resource Databases -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To merge the contents of a resource file into a database, use
+<function>XrmCombineFileDatabase</function>.
+<indexterm significance="preferred"><primary>XrmCombineFileDatabase</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmcombinefiledatabase'>
+<funcprototype>
+ <funcdef>Status <function>XrmCombineFileDatabase</function></funcdef>
+ <paramdef>char<parameter> *filename</parameter></paramdef>
+ <paramdef>XrmDatabase<parameter> *target_db</parameter></paramdef>
+ <paramdef>Bool<parameter> override</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>filename</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database file name.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>target_db</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database into which the source
+database is to be merged.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>override</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies whether source entries override target ones.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmCombineFileDatabase</function>
+function merges the contents of a resource file into a database.
+If the same specifier is used for an entry in both the file and
+the database,
+the entry in the file will replace the entry in the database
+if override is
+<symbol>True</symbol>;
+otherwise, the entry in the file is discarded.
+The file is parsed in the current locale.
+If the file cannot be read,
+a zero status is returned;
+otherwise, a nonzero status is returned.
+If target_db contains NULL,
+<function>XrmCombineFileDatabase</function>
+creates and returns a new database to it.
+Otherwise, the database pointed to by target_db is not destroyed by the merge.
+The database entries are merged without changing values or types,
+regardless of the locale of the database.
+The locale of the target database is not modified.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To merge the contents of one database into another database, use
+<function>XrmCombineDatabase</function>.
+<indexterm significance="preferred"><primary>XrmCombineDatabase</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmcombinedatabase'>
+<funcprototype>
+ <funcdef>void <function>XrmCombineDatabase</function></funcdef>
+ <paramdef>XrmDatabasesource_db,<parameter> *target_db</parameter></paramdef>
+ <paramdef>Bool<parameter> override</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>source_db</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database that is to be merged into the target database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>target_db</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database into which the source
+database is to be merged.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>override</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies whether source entries override target ones.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmCombineDatabase</function>
+function merges the contents of one database into another.
+If the same specifier is used for an entry in both databases,
+the entry in the source_db will replace the entry in the target_db
+if override is
+<symbol>True</symbol>;
+otherwise, the entry in source_db is discarded.
+If target_db contains NULL,
+<function>XrmCombineDatabase</function>
+simply stores source_db in it.
+Otherwise, source_db is destroyed by the merge, but the database pointed
+to by target_db is not destroyed.
+The database entries are merged without changing values or types,
+regardless of the locales of the databases.
+The locale of the target database is not modified.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To merge the contents of one database into another database with override
+semantics, use
+<function>XrmMergeDatabases</function>.
+<indexterm significance="preferred"><primary>XrmMergeDatabases</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmmergedatabases'>
+<funcprototype>
+ <funcdef>void <function>XrmMergeDatabases</function></funcdef>
+ <paramdef>XrmDatabasesource_db,<parameter> *target_db</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>source_db</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database that is to be merged into the target database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>target_db</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database into which the source
+database is to be merged.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Calling the
+<function>XrmMergeDatabases</function>
+function is equivalent to calling the
+<function>XrmCombineDatabase</function>
+function with an override argument of
+<symbol>True</symbol>.
+</para>
+</sect1>
+<sect1 id="Looking_Up_Resources">
+<title>Looking Up Resources</title>
+<!-- .XS -->
+<!-- (SN Looking Up Resources -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To retrieve a resource from a resource database, use
+<function>XrmGetResource</function>,
+<function>XrmQGetResource</function>,
+or
+<function>XrmQGetSearchResource</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+<indexterm significance="preferred"><primary>XrmGetResource</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmgetresource'>
+<funcprototype>
+ <funcdef>Bool <function>XrmGetResource</function></funcdef>
+ <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
+ <paramdef>char<parameter> *str_name</parameter></paramdef>
+ <paramdef>char<parameter> *str_class</parameter></paramdef>
+ <paramdef>char<parameter> **str_type_return</parameter></paramdef>
+ <paramdef>XrmValue<parameter> *value_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the database that is to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>str_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the fully qualified name of the value being retrieved (as a string).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>str_class</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the fully qualified class of the value being retrieved (as a string).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>str_type_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the representation type of the destination (as a string).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the value in the database.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+<indexterm significance="preferred"><primary>XrmQGetResource</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmqgetresource'>
+<funcprototype>
+ <funcdef>Bool <function>XrmQGetResource</function></funcdef>
+ <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
+ <paramdef>XrmNameList<parameter> quark_name</parameter></paramdef>
+ <paramdef>XrmClassList<parameter> quark_class</parameter></paramdef>
+ <paramdef>XrmRepresentation<parameter> *quark_type_return</parameter></paramdef>
+ <paramdef>XrmValue<parameter> *value_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the database that is to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>quark_name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the fully qualified name of the value being retrieved (as a quark).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>quark_class</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the fully qualified class of the value being retrieved (as a quark).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>quark_type_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the representation type of the destination (as a quark).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the value in the database.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmGetResource</function>
+and
+<function>XrmQGetResource</function>
+functions retrieve a resource from the specified database.
+Both take a fully qualified name/class pair, a destination
+resource representation, and the address of a value
+(size/address pair).
+The value and returned type point into database memory;
+therefore, you must not modify the data.
+</para>
+<para>
+<!-- .LP -->
+The database only frees or overwrites entries on
+<function>XrmPutResource</function>,
+<function>XrmQPutResource</function>,
+or
+<function>XrmMergeDatabases</function>.
+A client that is not storing new values into the database or
+is not merging the database should be safe using the address passed
+back at any time until it exits.
+If a resource was found, both
+<function>XrmGetResource</function>
+and
+<function>XrmQGetResource</function>
+return
+<symbol>True</symbol>;
+otherwise, they return
+<symbol>False</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+Most applications and toolkits do not make random probes
+into a resource database to fetch resources.
+The X toolkit access pattern for a resource database is quite stylized.
+A series of from 1 to 20 probes is made with only the
+last name/class differing in each probe.
+The
+<function>XrmGetResource</function>
+function is at worst a
+2<superscript><emphasis remap='I'>n</emphasis></superscript> algorithm,
+where <emphasis remap='I'>n</emphasis> is the length of the name/class list.
+This can be improved upon by the application programmer by prefetching a list
+of database levels that might match the first part of a name/class list.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain a list of database levels, use
+<function>XrmQGetSearchList</function>.
+<indexterm significance="preferred"><primary>XrmQGetSearchList</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmqgetsearchlist'>
+<funcprototype>
+ <funcdef>Bool <function>XrmQGetSearchResource</function></funcdef>
+ <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
+ <paramdef>XrmNameList<parameter> names</parameter></paramdef>
+ <paramdef>XrmClassList<parameter> classes</parameter></paramdef>
+ <paramdef>XrmSearchList<parameter> list_return</parameter></paramdef>
+ <paramdef>int<parameter> list_length</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the database that is to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>names</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a list of resource names.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>classes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a list of resource classes.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns a search list for further use.
+The caller must allocate sufficient space for the list before calling
+<function>XrmQGetSearchList</function>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list_length</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of entries (not the byte size) allocated for list_return.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmQGetSearchList</function>
+function takes a list of names and classes
+and returns a list of database levels where a match might occur.
+The returned list is in best-to-worst order and
+uses the same algorithm as
+<function>XrmGetResource</function>
+for determining precedence.
+If list_return was large enough for the search list,
+<function>XrmQGetSearchList</function>
+returns
+<symbol>True</symbol>;
+otherwise, it returns
+<symbol>False</symbol>.
+</para>
+<para>
+<!-- .LP -->
+The size of the search list that the caller must allocate is
+dependent upon the number of levels and wildcards in the resource specifiers
+that are stored in the database.
+The worst case length is
+3<superscript><emphasis remap='I'>n</emphasis></superscript>,
+where <emphasis remap='I'>n</emphasis> is the number of name or class
+components in names or classes.
+</para>
+<para>
+<!-- .LP -->
+When using
+<function>XrmQGetSearchList</function>
+followed by multiple probes for resources with a common name and class prefix,
+only the common prefix should be specified in the name and class list to
+<function>XrmQGetSearchList</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To search resource database levels for a given resource, use
+<function>XrmQGetSearchResource</function>.
+<indexterm significance="preferred"><primary>XrmQGetSearchResource</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmqgetsearchresource'>
+<funcprototype>
+ <funcdef>Bool <function>XrmQGetSearchResource</function></funcdef>
+ <paramdef>XrmSearchList<parameter> list</parameter></paramdef>
+ <paramdef>XrmName<parameter> name</parameter></paramdef>
+ <paramdef>XrmClass<parameter> class</parameter></paramdef>
+ <paramdef>XrmRepresentation<parameter> *type_return</parameter></paramdef>
+ <paramdef>XrmValue<parameter> *value_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the search list returned by
+<function>XrmQGetSearchList</function>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource name.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>class</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource class.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>type_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns data representation type.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the value in the database.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmQGetSearchResource</function>
+function searches the specified database levels for the resource
+that is fully identified by the specified name and class.
+The search stops with the first match.
+<function>XrmQGetSearchResource</function>
+returns
+<symbol>True</symbol>
+if the resource was found;
+otherwise, it returns
+<symbol>False</symbol>.
+</para>
+<para>
+<!-- .LP -->
+A call to
+<function>XrmQGetSearchList</function>
+with a name and class list containing all but the last component
+of a resource name followed by a call to
+<function>XrmQGetSearchResource</function>
+with the last component name and class returns the same database entry as
+<function>XrmGetResource</function>
+and
+<function>XrmQGetResource</function>
+with the fully qualified name and class.
+</para>
+</sect1>
+<sect1 id="Storing_into_a_Resource_Database">
+<title>Storing into a Resource Database</title>
+<!-- .XS -->
+<!-- (SN Storing into a Resource Database -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To store resources into the database, use
+<function>XrmPutResource</function>
+or
+<function>XrmQPutResource</function>.
+Both functions take a partial resource specification, a
+representation type, and a value.
+This value is copied into the specified database.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+<indexterm significance="preferred"><primary>XrmPutResource</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmputresource'>
+<funcprototype>
+ <funcdef>void <function>XrmPutResource</function></funcdef>
+ <paramdef>XrmDatabase<parameter> *database</parameter></paramdef>
+ <paramdef>char<parameter> *specifier</parameter></paramdef>
+ <paramdef>char<parameter> *type</parameter></paramdef>
+ <paramdef>XrmValue<parameter> *value</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>specifier</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a complete or partial specification of the resource.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>type</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the type of the resource.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the value of the resource, which is specified as a string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If database contains NULL,
+<function>XrmPutResource</function>
+creates a new database and returns a pointer to it.
+<function>XrmPutResource</function>
+is a convenience function that calls
+<function>XrmStringToBindingQuarkList</function>
+followed by:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+XrmQPutResource(database, bindings, quarks, XrmStringToQuark(type), value)
+</literallayout>
+If the specifier and type are not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+The value is stored in the database without modification.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+<indexterm significance="preferred"><primary>XrmQPutResource</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmqputresource'>
+<funcprototype>
+ <funcdef>void <function>XrmQPutResource</function></funcdef>
+ <paramdef>XrmDatabase<parameter> *database</parameter></paramdef>
+ <paramdef>XrmBindingList<parameter> bindings</parameter></paramdef>
+ <paramdef>XrmQuarkList<parameter> quarks</parameter></paramdef>
+ <paramdef>XrmRepresentation<parameter> type</parameter></paramdef>
+ <paramdef>XrmValue<parameter> *value</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bindings</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a list of bindings.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>quarks</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the complete or partial name or the class list of the resource.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>type</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the type of the resource.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the value of the resource, which is specified as a string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If database contains NULL,
+<function>XrmQPutResource</function>
+creates a new database and returns a pointer to it.
+If a resource entry with the identical bindings and quarks already
+exists in the database, the previous type and value are replaced by the new
+specified type and value.
+The value is stored in the database without modification.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To add a resource that is specified as a string, use
+<function>XrmPutStringResource</function>.
+<indexterm significance="preferred"><primary>XrmPutStringResource</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmputstringresource'>
+<funcprototype>
+ <funcdef>void <function>XrmPutStringResource</function></funcdef>
+ <paramdef>XrmDatabase<parameter> *database</parameter></paramdef>
+ <paramdef>char<parameter> *specifier</parameter></paramdef>
+ <paramdef>char<parameter> *value</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>specifier</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a complete or partial specification of the resource.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the value of the resource, which is specified as a string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If database contains NULL,
+<function>XrmPutStringResource</function>
+creates a new database and returns a pointer to it.
+<function>XrmPutStringResource</function>
+adds a resource with the specified value to the specified database.
+<function>XrmPutStringResource</function>
+is a convenience function that first calls
+<function>XrmStringToBindingQuarkList</function>
+on the specifier and then calls
+<function>XrmQPutResource</function>,
+using a ``String'' representation type.
+If the specifier is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+The value is stored in the database without modification.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To add a string resource using quarks as a specification, use
+<function>XrmQPutStringResource</function>.
+<indexterm significance="preferred"><primary>XrmQPutStringResource</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmqputstringresource'>
+<funcprototype>
+ <funcdef>void <function>XrmQPutStringResource</function></funcdef>
+ <paramdef>XrmDatabase<parameter> *database</parameter></paramdef>
+ <paramdef>XrmBindingList<parameter> bindings</parameter></paramdef>
+ <paramdef>XrmQuarkList<parameter> quarks</parameter></paramdef>
+ <paramdef>char<parameter> *value</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bindings</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies a list of bindings.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>quarks</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the complete or partial name or the class list of the resource.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the value of the resource, which is specified as a string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If database contains NULL,
+<function>XrmQPutStringResource</function>
+creates a new database and returns a pointer to it.
+<function>XrmQPutStringResource</function>
+is a convenience routine that constructs an
+<type>XrmValue</type>
+for the value string (by calling
+<function>strlen</function>
+to compute the size) and
+then calls
+<function>XrmQPutResource</function>,
+using a ``String'' representation type.
+The value is stored in the database without modification.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To add a single resource entry that is specified as a string that contains
+both a name and a value, use
+<function>XrmPutLineResource</function>.
+<indexterm significance="preferred"><primary>XrmPutLineResource</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmputlineresource'>
+<funcprototype>
+ <funcdef>void <function>XrmPutLineResource</function></funcdef>
+ <paramdef>XrmDatabase<parameter> *database</parameter></paramdef>
+ <paramdef>char<parameter> *line</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>line</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource name and value pair as a single string.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If database contains NULL,
+<function>XrmPutLineResource</function>
+creates a new database and returns a pointer to it.
+<function>XrmPutLineResource</function>
+adds a single resource entry to the specified database.
+The line should be in valid ResourceLine format (see section 15.1)
+terminated by a newline or null character;
+the database that results from using a string
+with incorrect syntax is implementation-dependent.
+The string is parsed in the locale of the database.
+If the
+<replaceable>ResourceName</replaceable>
+is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+Note that comment lines are not stored.
+</para>
+</sect1>
+<sect1 id="Enumerating_Database_Entries">
+<title>Enumerating Database Entries</title>
+<!-- .XS -->
+<!-- (SN Enumerating Database Entries -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To enumerate the entries of a database, use
+<function>XrmEnumerateDatabase</function>.
+<indexterm significance="preferred"><primary>XrmEnumerateDatabase</primary></indexterm>
+<!-- .sM -->
+</para>
+
+<literallayout class="monospaced">
+#define XrmEnumAllLevels 0
+#define XrmEnumOneLevel 0
+</literallayout>
+
+<funcsynopsis id='xrmenumeratedatabase'>
+<funcprototype>
+ <funcdef>Bool <function>XrmEnumerateDatabase</function></funcdef>
+ <paramdef>XrmDatabase<parameter> database</parameter></paramdef>
+ <paramdef>XrmNameList<parameter> name_prefix</parameter></paramdef>
+ <paramdef>XrmClassList<parameter> class_prefix</parameter></paramdef>
+ <paramdef>int<parameter> mode</parameter></paramdef>
+ <paramdef>Bool<parameter> (*proc)()</parameter></paramdef>
+ <paramdef>XPointer<parameter> arg</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>name_prefix</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource name prefix.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>class_prefix</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource class prefix.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>mode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of levels to enumerate.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>proc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the procedure that is to be called for each matching entry.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>arg</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the user-supplied argument that will be passed to the procedure.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmEnumerateDatabase</function>
+function calls the specified procedure for each resource in the database
+that would match some completion of the given name/class resource prefix.
+The order in which resources are found is implementation-dependent.
+If mode is
+<symbol>XrmEnumOneLevel</symbol>,
+a resource must match the given name/class prefix with
+just a single name and class appended. If mode is
+<symbol>XrmEnumAllLevels</symbol>,
+the resource must match the given name/class prefix with one or more names and
+classes appended.
+If the procedure returns
+<symbol>True</symbol>,
+the enumeration terminates and the function returns
+<symbol>True</symbol>.
+If the procedure always returns
+<symbol>False</symbol>,
+all matching resources are enumerated and the function returns
+<symbol>False</symbol>.
+</para>
+<para>
+<!-- .LP -->
+The procedure is called with the following arguments:
+</para>
+<para>
+<!-- .LP -->
+<!-- .\" Start marker code here -->
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+(*<emphasis remap='I'>proc</emphasis>)(<emphasis remap='I'>database</emphasis>, <emphasis remap='I'>bindings</emphasis>, <emphasis remap='I'>quarks</emphasis>, <emphasis remap='I'>type</emphasis>, <emphasis remap='I'>value</emphasis>, <emphasis remap='I'>arg</emphasis>)
+ XrmDatabase *<emphasis remap='I'>database</emphasis>;
+ XrmBindingList <emphasis remap='I'>bindings</emphasis>;
+ XrmQuarkList <emphasis remap='I'>quarks</emphasis>;
+ XrmRepresentation *<emphasis remap='I'>type</emphasis>;
+ XrmValue *<emphasis remap='I'>value</emphasis>;
+ XPointer <emphasis remap='I'>arg</emphasis>;
+</literallayout>
+<!-- .\" End marker code here -->
+</para>
+<para>
+<!-- .LP -->
+The bindings and quarks lists are terminated by
+<symbol>NULLQUARK</symbol>.
+Note that pointers
+to the database and type are passed, but these values should not be modified.
+</para>
+<para>
+<!-- .LP -->
+The procedure must not modify the database.
+If Xlib has been initialized for threads, the procedure is called with
+the database locked and the result of a call by the procedure to any
+Xlib function using the same database is not defined.
+</para>
+</sect1>
+<sect1 id="Parsing_Command_Line_Options">
+<title>Parsing Command Line Options</title>
+<!-- .XS -->
+<!-- (SN Parsing Command Line Options -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The
+<function>XrmParseCommand</function>
+function can be used to parse the command line arguments to a program
+and modify a resource database with selected entries from the command line.
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XrmOptionKind</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef enum {
+ XrmoptionNoArg, /* Value is specified in XrmOptionDescRec.value */
+ XrmoptionIsArg, /* Value is the option string itself */
+ XrmoptionStickyArg, /* Value is characters immediately following option */
+ XrmoptionSepArg, /* Value is next argument in argv */
+ XrmoptionResArg, /* Resource and value in next argument in argv */
+ XrmoptionSkipArg, /* Ignore this option and the next argument in argv */
+ XrmoptionSkipLine, /* Ignore this option and the rest of argv */
+ XrmoptionSkipNArgs /* Ignore this option and the next
+ \ \ \ XrmOptionDescRec.value arguments in argv */
+} XrmOptionKind;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Note that
+<constant>XrmoptionSkipArg</constant>
+is equivalent to
+<constant>XrmoptionSkipNArgs</constant>
+with the
+<structname>XrmOptionDescRec</structname>.<structfield>value</structfield>
+field containing the value one.
+Note also that the value zero for
+<constant>XrmoptionSkipNArgs</constant>
+indicates that only the option itself is to be skipped.
+</para>
+<para>
+<!-- .LP -->
+<indexterm significance="preferred"><primary>XrmOptionDescRec</primary></indexterm>
+<!-- .sM -->
+<literallayout class="monospaced">
+<!-- .TA .5i 2.5i -->
+<!-- .ta .5i 2.5i -->
+typedef struct {
+ char *option; /* Option specification string in argv */
+ char *specifier; /* Binding and resource name (sans application name) */
+ XrmOptionKind argKind; /* Which style of option it is */
+ XPointer value; /* Value to provide if XrmoptionNoArg or
+ \ \ \ XrmoptionSkipNArgs */
+} XrmOptionDescRec, *XrmOptionDescList;
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To load a resource database from a C command line, use
+<function>XrmParseCommand</function>.
+<indexterm significance="preferred"><primary>XrmParseCommand</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrmparsecommand'>
+<funcprototype>
+ <funcdef>void <function>XrmParseCommand</function></funcdef>
+ <paramdef>XrmDatabase<parameter> *database</parameter></paramdef>
+ <paramdef>XrmOptionDescList<parameter> table</parameter></paramdef>
+ <paramdef>int<parameter> table_count</parameter></paramdef>
+ <paramdef>char<parameter> *name</parameter></paramdef>
+ <paramdef>int<parameter> *argc_in_out</parameter></paramdef>
+ <paramdef>char<parameter> **argv_in_out</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>database</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource database.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>table</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the table of command line arguments to be parsed.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>table_count</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of entries in the table.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>name</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the application name.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>argc_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of arguments and returns the number of remaining arguments.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>argv_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the command line arguments
+and returns the remaining arguments.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XrmParseCommand</function>
+function parses an (argc, argv) pair according to the specified option table,
+loads recognized options into the specified database with type ``String,''
+and modifies the (argc, argv) pair to remove all recognized options.
+If database contains NULL,
+<function>XrmParseCommand</function>
+creates a new database and returns a pointer to it.
+Otherwise, entries are added to the database specified.
+If a database is created, it is created in the current locale.
+</para>
+<para>
+<!-- .LP -->
+The specified table is used to parse the command line.
+Recognized options in the table are removed from argv,
+and entries are added to the specified resource database
+in the order they occur in argv.
+The table entries contain information on the option string,
+the option name, the style of option,
+and a value to provide if the option kind is
+<constant>XrmoptionNoArg</constant>.
+The option names are compared byte-for-byte to arguments in argv,
+independent of any locale.
+The resource values given in the table are stored in the resource database
+without modification.
+All resource database entries are created
+using a ``String'' representation type.
+The argc argument specifies the number of arguments in argv
+and is set on return to the remaining number of arguments that were not parsed.
+The name argument should be the name of your application
+for use in building the database entry.
+The name argument is prefixed to the resourceName in the option table
+before storing a database entry.
+The name argument is treated as a single component, even if it
+has embedded periods.
+No separating (binding) character is inserted,
+so the table must contain either a period (.) or an asterisk (*)
+as the first character in each resourceName entry.
+To specify a more completely qualified resource name,
+the resourceName entry can contain multiple components.
+If the name argument and the resourceNames are not in the
+Host Portable Character Encoding,
+the result is implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+The following provides a sample option table:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+<!-- .TA 1.25i 3.25i 4.75i -->
+<!-- .ta 1.25i 3.25i 4.75i -->
+static XrmOptionDescRec opTable[] = {
+{"-background", "*background", XrmoptionSepArg, (XPointer) NULL},
+{"-bd", "*borderColor", XrmoptionSepArg, (XPointer) NULL},
+{"-bg", "*background", XrmoptionSepArg, (XPointer) NULL},
+{"-borderwidth", "*TopLevelShell.borderWidth", XrmoptionSepArg, (XPointer) NULL},
+{"-bordercolor", "*borderColor", XrmoptionSepArg, (XPointer) NULL},
+{"-bw", "*TopLevelShell.borderWidth", XrmoptionSepArg, (XPointer) NULL},
+{"-display", ".display", XrmoptionSepArg, (XPointer) NULL},
+{"-fg", "*foreground", XrmoptionSepArg, (XPointer) NULL},
+{"-fn", "*font", XrmoptionSepArg, (XPointer) NULL},
+{"-font", "*font", XrmoptionSepArg, (XPointer) NULL},
+{"-foreground", "*foreground", XrmoptionSepArg, (XPointer) NULL},
+{"-geometry", ".TopLevelShell.geometry", XrmoptionSepArg, (XPointer) NULL},
+{"-iconic", ".TopLevelShell.iconic", XrmoptionNoArg, (XPointer) "on"},
+{"-name", ".name", XrmoptionSepArg, (XPointer) NULL},
+{"-reverse", "*reverseVideo", XrmoptionNoArg, (XPointer) "on"},
+{"-rv", "*reverseVideo", XrmoptionNoArg, (XPointer) "on"},
+{"-synchronous", "*synchronous", XrmoptionNoArg, (XPointer) "on"},
+{"-title", ".TopLevelShell.title", XrmoptionSepArg, (XPointer) NULL},
+{"-xrm", NULL, XrmoptionResArg, (XPointer) NULL},
+};
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+In this table, if the -background (or -bg) option is used to set
+background colors, the stored resource specifier matches all
+resources of attribute background.
+If the -borderwidth option is used,
+the stored resource specifier applies only to border width
+attributes of class TopLevelShell (that is, outer-most windows, including
+pop-up windows).
+If the -title option is used to set a window name,
+only the topmost application windows receive the resource.
+</para>
+<para>
+<!-- .LP -->
+When parsing the command line,
+any unique unambiguous abbreviation for an option name in the table is
+considered a match for the option.
+Note that uppercase and lowercase matter.
+<!-- .bp -->
+
+</para>
+</sect1>
+</chapter>
diff --git a/libX11/specs/libX11/CH16.xml b/libX11/specs/libX11/CH16.xml
index 9c7bf8c01..db42bb170 100644
--- a/libX11/specs/libX11/CH16.xml
+++ b/libX11/specs/libX11/CH16.xml
@@ -1,4160 +1,4160 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
- "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
-<chapter id="application_utility_functions">
-<title>Application Utility Functions</title>
-<!-- .sp 2 -->
-<!-- .nr H1 16 -->
-<!-- .nr H2 0 -->
-<!-- .nr H3 0 -->
-<!-- .nr H4 0 -->
-<!-- .nr H5 0 -->
-<!-- .na -->
-<para>
-<!-- .LP -->
-<!-- .XS -->
-<!-- Chapter 16: Application Utility Functions -->
-<!-- .XE -->
-Once you have initialized the X system,
-you can use the Xlib utility functions to:
-</para>
-<itemizedlist>
- <listitem>
- <para>
-Use keyboard utility functions
- </para>
- </listitem>
- <listitem>
- <para>
-Use Latin-1 keyboard event functions
- </para>
- </listitem>
- <listitem>
- <para>
-Allocate permanent storage
- </para>
- </listitem>
- <listitem>
- <para>
-Parse the window geometry
- </para>
- </listitem>
- <listitem>
- <para>
-Manipulate regions
- </para>
- </listitem>
- <listitem>
- <para>
-Use cut buffers
- </para>
- </listitem>
- <listitem>
- <para>
-Determine the appropriate visual type
- </para>
- </listitem>
- <listitem>
- <para>
-Manipulate images
- </para>
- </listitem>
- <listitem>
- <para>
-Manipulate bitmaps
- </para>
- </listitem>
- <listitem>
- <para>
-Use the context manager
- </para>
- </listitem>
-</itemizedlist>
-<para>
-<!-- .LP -->
-As a group,
-the functions discussed in this chapter provide the functionality that
-is frequently needed and that spans toolkits.
-Many of these functions do not generate actual protocol requests to the server.
-</para>
-<sect1 id="Using_Keyboard_Utility_Functions">
-<title>Using Keyboard Utility Functions</title>
-<!-- .XS -->
-<!-- (SN Using Keyboard Utility Functions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-This section discusses mapping between KeyCodes and KeySyms,
-classifying KeySyms, and mapping between KeySyms and string names.
-The first three functions in this section operate on a cached copy of the
-server keyboard mapping.
-The first four KeySyms for each KeyCode
-are modified according to the rules given in section 12.7.
-To obtain the untransformed KeySyms defined for a key,
-use the functions described in section 12.7.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain a KeySym for the KeyCode of an event, use
-<function>XLookupKeysym</function>.
-<indexterm significance="preferred"><primary>XLookupKeysym</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>KeySym <function>XLookupKeysym</function></funcdef>
- <paramdef>XKeyEvent<parameter> *key_event</parameter></paramdef>
- <paramdef>int<parameter> index</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>key_event</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<symbol>KeyPress</symbol>
-or
-<symbol>KeyRelease</symbol>
-event.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>index</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the index into the KeySyms list for the event's KeyCode.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XLookupKeysym</function>
-function uses a given keyboard event and the index you specified to return
-the KeySym from the list that corresponds to the KeyCode member in the
-<type>XKeyPressedEvent</type>
-or
-<type>XKeyReleasedEvent</type>
-structure.
-If no KeySym is defined for the KeyCode of the event,
-<function>XLookupKeysym</function>
-returns
-<symbol>NoSymbol</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain a KeySym for a specific KeyCode, use
-<function>XKeycodeToKeysym</function>.
-<indexterm significance="preferred"><primary>XKeycodeToKeysym</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>KeySym <function>XKeycodeToKeysym</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>KeyCode<parameter> keycode</parameter></paramdef>
- <paramdef>int<parameter> index</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keycode</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeyCode.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>index</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the element of KeyCode vector.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XKeycodeToKeysym</function>
-function uses internal Xlib tables
-and returns the KeySym defined for the specified KeyCode and
-the element of the KeyCode vector.
-If no symbol is defined,
-<function>XKeycodeToKeysym</function>
-returns
-<symbol>NoSymbol</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain a KeyCode for a key having a specific KeySym, use
-<function>XKeysymToKeycode</function>.
-<indexterm significance="preferred"><primary>XKeysymToKeycode</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>KeyCode <function>XKeysymToKeycode</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>KeySym<parameter> keysym</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeySym that is to be searched for.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If the specified KeySym is not defined for any KeyCode,
-<function>XKeysymToKeycode</function>
-returns zero.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-The mapping between KeyCodes and KeySyms is cached internal to Xlib.
-When this information is changed at the server, an Xlib function must
-be called to refresh the cache.
-To refresh the stored modifier and keymap information, use
-<function>XRefreshKeyboardMapping</function>.
-<indexterm significance="preferred"><primary>XRefreshKeyboardMapping</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XRefreshKeyboardMapping</function></funcdef>
- <paramdef>XMappingEvent<parameter> *event_map</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_map</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the mapping event that is to be used.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XRefreshKeyboardMapping</function>
-function refreshes the stored modifier and keymap information.
-You usually call this function when a
-<symbol>MappingNotify</symbol>
-event with a request member of
-<symbol>MappingKeyboard</symbol>
-or
-<symbol>MappingModifier</symbol>
-occurs.
-The result is to update Xlib's knowledge of the keyboard.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the uppercase and lowercase forms of a KeySym, use
-<function>XConvertCase</function>.
-<indexterm significance="preferred"><primary>XConvertCase</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>void <function>XConvertCase</function></funcdef>
- <paramdef>KeySym<parameter> keysym</parameter></paramdef>
- <paramdef>KeySym<parameter> *lower_return</parameter></paramdef>
- <paramdef>KeySym<parameter> *upper_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<!-- .ds Fn converted -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeySym that is to be (Fn.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>lower_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the lowercase form of keysym, or keysym.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>upper_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the uppercase form of keysym, or keysym.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XConvertCase</function>
-function returns the uppercase and lowercase forms of the specified Keysym,
-if the KeySym is subject to case conversion;
-otherwise, the specified KeySym is returned to both lower_return and
-upper_return.
-Support for conversion of other than Latin and Cyrillic KeySyms is
-implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-KeySyms have string names as well as numeric codes.
-To convert the name of the KeySym to the KeySym code, use
-<function>XStringToKeysym</function>.
-<indexterm significance="preferred"><primary>XStringToKeysym</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>KeySym <function>XStringToKeysym</function></funcdef>
- <paramdef>char<parameter> *string</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the name of the KeySym that is to be converted.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Standard KeySym names are obtained from
-<filename class="headerfile">&lt;X11/keysymdef.h&gt;</filename>
-<indexterm type="file"><primary><filename class="headerfile">X11/keysymdef.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/keysymdef.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/keysymdef.h&gt;</filename></secondary></indexterm>
-by removing the XK_ prefix from each name.
-KeySyms that are not part of the Xlib standard also may be obtained
-with this function.
-The set of KeySyms that are available in this manner
-and the mechanisms by which Xlib obtains them is implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-If the KeySym name is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-If the specified string does not match a valid KeySym,
-<function>XStringToKeysym</function>
-returns
-<symbol>NoSymbol</symbol>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To convert a KeySym code to the name of the KeySym, use
-<function>XKeysymToString</function>.
-<indexterm significance="preferred"><primary>XKeysymToString</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XKeysymToString</function></funcdef>
- <paramdef>KeySym<parameter> keysym</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<!-- .ds Fn converted -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeySym that is to be (Fn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The returned string is in a static area and must not be modified.
-The returned string is in the Host Portable Character Encoding.
-If the specified KeySym is not defined,
-<function>XKeysymToString</function>
-returns a NULL.
-</para>
-<sect2 id="KeySym_Classification_Macros">
-<title>KeySym Classification Macros</title>
-<!-- .XS -->
-<!-- (SN KeySym Classification Macros -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-You may want to test if a KeySym is, for example,
-on the keypad or on one of the function keys.
-You can use KeySym macros to perform the following tests.
-</para>
-<para>IsCursorKey(<emphasis remap='I'>keysym</emphasis>)</para>
-<!-- .FN -->
-<!-- .ds Fn tested -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeySym that is to be tested.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>IsCursorKey</primary></indexterm>
-Returns
-<symbol>True</symbol>
-if the specified KeySym is a cursor key.
-</para>
-<!-- .LP -->
-<!-- .sp -->
-<!-- .sM -->
-<para>IsFunctionKey(<emphasis remap='I'>keysym</emphasis>)</para>
-<!-- .FN -->
-<!-- .ds Fn tested -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeySym that is to be tested.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>IsFunctionKey</primary></indexterm>
-Returns
-<symbol>True</symbol>
-if the specified KeySym is a function key.
-</para>
-<!-- .LP -->
-<!-- .sp -->
-<!-- .sM -->
-<para>IsKeypadKey(<emphasis remap='I'>keysym</emphasis>)</para>
-<!-- .FN -->
-<!-- .ds Fn tested -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeySym that is to be (Fn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>IsKeypadKey</primary></indexterm>
-Returns
-<symbol>True</symbol>
-if the specified KeySym is a standard keypad key.
-</para>
-<!-- .LP -->
-<!-- .sp -->
-<!-- .sM -->
-<para>IsPrivateKeypadKey(<emphasis remap='I'>keysym</emphasis>)</para>
-
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeySym that is to be (Fn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>IsPrivateKeypadKey</primary></indexterm>
-Returns
-<symbol>True</symbol>
-if the specified KeySym is a vendor-private keypad key.
-</para>
-
-<!-- .LP -->
-<!-- .sp -->
-<!-- .sM -->
-<para>IsMiscFunctionKey(<emphasis remap='I'>keysym</emphasis>)</para>
-<!-- .FN -->
-<!-- .ds Fn tested -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeySym that is to be (Fn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>IsMiscFunctionKey</primary></indexterm>
-Returns
-<symbol>True</symbol>
-if the specified KeySym is a miscellaneous function key.
-</para>
-<!-- .LP -->
-<!-- .sp -->
-<!-- .sM -->
-<para>IsModifierKey(<emphasis remap='I'>keysym</emphasis>)</para>
-
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeySym that is to be tested.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>IsModifierKey</primary></indexterm>
-Returns
-<symbol>True</symbol>
-if the specified KeySym is a modifier key.
-</para>
-
-<para>IsPFKey(<emphasis remap='I'>keysym</emphasis>)</para>
-
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeySym that is to be tested.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<indexterm significance="preferred"><primary>IsPFKey</primary></indexterm>
-Returns
-<symbol>True</symbol>
-if the specified KeySym is a PF key.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Using_Latin_Keyboard_Event_Functions">
-<title>Using Latin-1 Keyboard Event Functions</title>
-<!-- .XS -->
-<!-- (SN Using Latin-1 Keyboard Event Functions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Chapter 13 describes internationalized text input facilities,
-but sometimes it is expedient to write an application that
-only deals with Latin-1 characters and ASCII controls,
-so Xlib provides a simple function for that purpose.
-<function>XLookupString</function>
-handles the standard modifier semantics described in section 12.7.
-This function does not use any of the input method facilities
-described in chapter 13 and does not depend on the current locale.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To map a key event to an ISO Latin-1 string, use
-<function>XLookupString</function>.
-<indexterm significance="preferred"><primary>XLookupString</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XLookupString</function></funcdef>
- <paramdef>XKeyEvent<parameter> *event_struct</parameter></paramdef>
- <paramdef>char<parameter> *buffer_return</parameter></paramdef>
- <paramdef>int<parameter> bytes_buffer</parameter></paramdef>
- <paramdef>KeySym<parameter> *keysym_return</parameter></paramdef>
- <paramdef>XComposeStatus<parameter> *status_in_out</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>event_struct</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the key event structure to be used.
-You can pass
-<type>XKeyPressedEvent</type>
-or
-<type>XKeyReleasedEvent</type>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>buffer_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the translated characters.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bytes_buffer</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the length of the buffer.
-No more than bytes_buffer of translation are returned.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the KeySym computed from the event if this argument is not NULL.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>status_in_out</emphasis>
- </term>
- <listitem>
- <para>
-Specifies or returns the
-<structname>XComposeStatus</structname>
-structure or NULL.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XLookupString</function>
-function translates a key event to a KeySym and a string.
-The KeySym is obtained by using the standard interpretation of the
-<symbol>Shift</symbol>,
-<symbol>Lock</symbol>,
-group, and numlock modifiers as defined in the X Protocol specification.
-If the KeySym has been rebound (see
-<function>XRebindKeysym</function>),
-the bound string will be stored in the buffer.
-Otherwise, the KeySym is mapped, if possible, to an ISO Latin-1 character
-or (if the Control modifier is on) to an ASCII control character,
-and that character is stored in the buffer.
-<function>XLookupString</function>
-returns the number of characters that are stored in the buffer.
-</para>
-<para>
-<!-- .LP -->
-If present (non-NULL),
-the
-<structname>XComposeStatus</structname>
-structure records the state,
-which is private to Xlib,
-that needs preservation across calls to
-<function>XLookupString</function>
-to implement compose processing.
-The creation of
-<structname>XComposeStatus</structname>
-structures is implementation-dependent;
-a portable program must pass NULL for this argument.
-</para>
-<para>
-<!-- .LP -->
-<function>XLookupString</function>
-depends on the cached keyboard information mentioned in the
-previous section, so it is necessary to use
-<function>XRefreshKeyboardMapping</function>
-to keep this information up-to-date.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To rebind the meaning of a KeySym for
-<function>XLookupString</function>,
-use
-<function>XRebindKeysym</function>.
-<indexterm significance="preferred"><primary>XRebindKeysym</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XRebindKeysym</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>KeySym<parameter> keysym</parameter></paramdef>
- <paramdef>KeySym<parameter> list[&hairsp;]</parameter></paramdef>
- <paramdef>int<parameter> mod_count</parameter></paramdef>
- <paramdef>unsignedchar<parameter> *string</parameter></paramdef>
- <paramdef>int<parameter> num_bytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Fn rebound -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>keysym</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeySym that is to be (Fn.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>list</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the KeySyms to be used as modifiers.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>mod_count</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of modifiers in the modifier list.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>string</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the string that is copied and will be returned by
-<function>XLookupString</function>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>num_bytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes in the string argument.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XRebindKeysym</function>
-function can be used to rebind the meaning of a KeySym for the client.
-It does not redefine any key in the X server but merely
-provides an easy way for long strings to be attached to keys.
-<function>XLookupString</function>
-returns this string when the appropriate set of
-modifier keys are pressed and when the KeySym would have been used for
-the translation.
-No text conversions are performed;
-the client is responsible for supplying appropriately encoded strings.
-Note that you can rebind a KeySym that may not exist.
-</para>
-</sect1>
-<sect1 id="Allocating_Permanent_Storage">
-<title>Allocating Permanent Storage</title>
-<!-- .XS -->
-<!-- (SN Allocating Permanent Storage -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To allocate some memory you will never give back, use
-<function>Xpermalloc</function>.
-<indexterm significance="preferred"><primary>Xpermalloc</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>Xpermalloc</function></funcdef>
- <paramdef>unsignedint<parameter> size</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>Xpermalloc</function>
-function allocates storage that can never be freed for the life of the
-program. The memory is allocated with alignment for the C type double.
-This function may provide some performance and space savings over
-the standard operating system memory allocator.
-</para>
-</sect1>
-<sect1 id="Parsing_the_Window_Geometry">
-<title>Parsing the Window Geometry</title>
-<!-- .XS -->
-<!-- (SN Parsing the Window Geometry -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To parse standard window geometry strings, use
-<function>XParseGeometry</function>.
-<indexterm><primary>Window</primary><secondary>determining location</secondary></indexterm>
-<indexterm significance="preferred"><primary>XParseGeometry</primary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XParseGeometry</function></funcdef>
- <paramdef>char<parameter> *parsestring</parameter></paramdef>
- <paramdef>int*x_return,<parameter> *y_return</parameter></paramdef>
- <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>parsestring</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the string you want to parse.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the x and y offsets.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the width and height determined.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-By convention,
-X applications use a standard string to indicate window size and placement.
-<function>XParseGeometry</function>
-makes it easier to conform to this standard because it allows you
-to parse the standard window geometry.
-Specifically, this function lets you parse strings of the form:
-</para>
-<para>
-<!-- .LP -->
-<!-- .\" Start marker code here -->
-<literallayout class="monospaced">
-[=][&lt;<emphasis remap='I'>width</emphasis>&gt;{xX}&lt;<emphasis remap='I'>height</emphasis>&gt;][{+-}&lt;<emphasis remap='I'>xoffset</emphasis>&gt;{+-}&lt;<emphasis remap='I'>yoffset</emphasis>&gt;]
-</literallayout>
-<!-- .\" End marker code here -->
-</para>
-<para>
-<!-- .LP -->
-The fields map into the arguments associated with this function.
-(Items enclosed in &lt;&hairsp;&gt; are integers, items in [&hairsp;] are optional, and
-items enclosed in {&hairsp;} indicate ``choose one of.''
-Note that the brackets should not appear in the actual string.)
-If the string is not in the Host Portable Character Encoding,
-the result is implementation-dependent.
-</para>
-<para>
-<!-- .LP -->
-The
-<function>XParseGeometry</function>
-function returns a bitmask that indicates which of the four values (width,
-height, xoffset, and yoffset) were actually found in the string
-and whether the x and y values are negative.
-By convention, &minus;0 is not equal to +0, because the user needs to
-be able to say ``position the window relative to the right or bottom edge.''
-For each value found, the corresponding argument is updated.
-For each value not found, the argument is left unchanged.
-The bits are represented by
-<symbol>XValue</symbol>,
-<symbol>YValue</symbol>,
-<symbol>WidthValue</symbol>,
-<symbol>HeightValue</symbol>,
-<symbol>XNegative</symbol>,
-or
-<symbol>YNegative</symbol>
-and are defined in
-<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>.
-<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-They will be set whenever one of the values is defined
-or one of the signs is set.
-</para>
-<para>
-<!-- .LP -->
-If the function returns either the
-<symbol>XValue</symbol>
-or
-<symbol>YValue</symbol>
-flag,
-you should place the window at the requested position.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To construct a window's geometry information, use
-<function>XWMGeometry</function>.
-<indexterm significance="preferred"><primary>XWMGeometry</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XWMGeometry</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> screen</parameter></paramdef>
- <paramdef>char<parameter> *user_geom</parameter></paramdef>
- <paramdef>char<parameter> *def_geom</parameter></paramdef>
- <paramdef>unsignedint<parameter> bwidth</parameter></paramdef>
- <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
- <paramdef>int*x_return,<parameter> *y_return</parameter></paramdef>
- <paramdef>int<parameter> *width_return</parameter></paramdef>
- <paramdef>int<parameter> *height_return</parameter></paramdef>
- <paramdef>int<parameter> *gravity_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the screen.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>user_geom</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the user-specified geometry or NULL.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>def_geom</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the application's default geometry or NULL.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bwidth</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the border width.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>hints</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the size hints for the window in its normal state.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the x and y offsets.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the width and height determined.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gravity_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the window gravity.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XWMGeometry</function>
-function combines any geometry information (given in the format used by
-<function>XParseGeometry</function>)
-specified by the user and by the calling program with size hints
-(usually the ones to be stored in <property>WM_NORMAL_HINTS</property>) and returns the position,
-size, and gravity
-(<symbol>NorthWestGravity</symbol>,
-<symbol>NorthEastGravity</symbol>,
-<symbol>SouthEastGravity</symbol>,
-or
-<symbol>SouthWestGravity</symbol>)
-that describe the window.
-If the base size is not set in the
-<structname>XSizeHints</structname>
-structure,
-the minimum size is used if set.
-Otherwise, a base size of zero is assumed.
-If no minimum size is set in the hints structure,
-the base size is used.
-A mask (in the form returned by
-<function>XParseGeometry</function>)
-that describes which values came from the user specification
-and whether or not the position coordinates are relative
-to the right and bottom edges is returned.
-Note that these coordinates will have already been accounted for
-in the x_return and y_return values.
-</para>
-<para>
-<!-- .LP -->
-Note that invalid geometry specifications can cause a width or height
-of zero to be returned.
-The caller may pass the address of the hints win_gravity field
-as gravity_return to update the hints directly.
-</para>
-</sect1>
-
-<sect1 id="Manipulating_Regions">
-<title>Manipulating Regions</title>
-<!-- .XS -->
-<!-- (SN Manipulating Regions -->
-<!-- .XE -->
-<para>
-Regions are arbitrary sets of pixel locations.
-Xlib provides functions for manipulating regions.
-The opaque type
-<structname>Region</structname>
-is defined in
-<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>.
-<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-Xlib provides functions that you can use to manipulate regions.
-This section discusses how to:
-</para>
-
-<itemizedlist>
- <listitem>
- <para>
-Create, copy, or destroy regions
- </para>
- </listitem>
- <listitem>
- <para>
-Move or shrink regions
- </para>
- </listitem>
- <listitem>
- <para>
-Compute with regions
- </para>
- </listitem>
- <listitem>
- <para>
-Determine if regions are empty or equal
- </para>
- </listitem>
- <listitem>
- <para>
-Locate a point or rectangle in a region
- </para>
- </listitem>
-</itemizedlist>
-
-<sect2 id="Creating_Copying_or_Destroying_Regions">
-<title>Creating, Copying, or Destroying Regions</title>
-<!-- .XS -->
-<!-- (SN Creating, Copying, or Destroying Regions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To create a new empty region, use
-<function>XCreateRegion</function>.
-</para>
-<para>Region XCreateRegion()</para>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To generate a region from a polygon, use
-<function>XPolygonRegion</function>.
-</para>
-<indexterm significance="preferred"><primary>XPolygonRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Region <function>XPolygonRegion</function></funcdef>
- <paramdef>XPoint<parameter> points[]</parameter></paramdef>
- <paramdef>int<parameter> n</parameter></paramdef>
- <paramdef>int<parameter> fill_rule</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>points</emphasis>
- </term>
- <listitem>
- <para>
-Specifies an array of points.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>n</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of points in the polygon.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>fill_rule</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the fill-rule you want to set for the specified GC.
-You can pass
-<symbol>EvenOddRule</symbol>
-or
-<symbol>WindingRule</symbol>.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XPolygonRegion</function>
-function returns a region for the polygon defined by the points array.
-For an explanation of fill_rule,
-see
-<function>XCreateGC</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set the clip-mask of a GC to a region, use
-<function>XSetRegion</function>.
-<indexterm significance="preferred"><primary>XSetRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSetRegion</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>GC<parameter> gc</parameter></paramdef>
- <paramdef>Region<parameter> r</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>gc</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the GC.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>r</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the region.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSetRegion</function>
-function sets the clip-mask in the GC to the specified region.
-The region is specified relative to the drawable's origin.
-The resulting GC clip origin is implementation-dependent.
-Once it is set in the GC,
-the region can be destroyed.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To deallocate the storage associated with a specified region, use
-<function>XDestroyRegion</function>.
-<indexterm significance="preferred"><primary>XDestroyRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDestroyRegion</function></funcdef>
- <paramdef>Region<parameter> r</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>r</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the region.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-</para>
-</sect2>
-<sect2 id="Moving_or_Shrinking_Regions">
-<title>Moving or Shrinking Regions</title>
-<!-- .XS -->
-<!-- (SN Moving or Shrinking Regions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To move a region by a specified amount, use
-<function>XOffsetRegion</function>.
-<indexterm significance="preferred"><primary>XOffsetRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XOffsetRegion</function></funcdef>
- <paramdef>Region<parameter> r</parameter></paramdef>
- <paramdef>intdx,<parameter> dy</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>r</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the region.
-<!-- .ds Dy move -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dx</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dy</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates,
-which define the amount you want to (Dy the specified region.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To reduce a region by a specified amount, use
-<function>XShrinkRegion</function>.
-<indexterm significance="preferred"><primary>XShrinkRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XShrinkRegion</function></funcdef>
- <paramdef>Region<parameter> r</parameter></paramdef>
- <paramdef>intdx,<parameter> dy</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>r</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the region.
-<!-- .ds Dy shrink -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dx</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dy</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates,
-which define the amount you want to (Dy the specified region.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Positive values shrink the size of the region,
-and negative values expand the region.
-</para>
-</sect2>
-<sect2 id="Computing_with_Regions">
-<title>Computing with Regions</title>
-<!-- .XS -->
-<!-- (SN Computing with Regions -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To generate the smallest rectangle enclosing a region, use
-<function>XClipBox</function>.
-<indexterm significance="preferred"><primary>XClipBox</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XClipBox</function></funcdef>
- <paramdef>Region<parameter> r</parameter></paramdef>
- <paramdef>XRectangle<parameter> *rect_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>r</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the region.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>rect_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the smallest enclosing rectangle.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XClipBox</function>
-function returns the smallest rectangle enclosing the specified region.
-<!-- .sp -->
-</para>
-<para>
-<!-- .LP -->
-To compute the intersection of two regions, use
-<function>XIntersectRegion</function>.
-<indexterm significance="preferred"><primary>XIntersectRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XIntersectRegion</function></funcdef>
- <paramdef>Regionsra,srb,<parameter> dr_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>sra</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>srb</emphasis>
- </term>
- <listitem>
- <para>
-Specify the two regions with which you want to perform the computation.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dr_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the result of the computation.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To compute the union of two regions, use
-<function>XUnionRegion</function>.
-<indexterm significance="preferred"><primary>XUnionRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XUnionRegion</function></funcdef>
- <paramdef>Regionsra,srb,<parameter> dr_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>sra</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>srb</emphasis>
- </term>
- <listitem>
- <para>
-Specify the two regions with which you want to perform the computation.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dr_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the result of the computation.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-<!-- .sp -->
-To create a union of a source region and a rectangle, use
-<function>XUnionRectWithRegion</function>.
-<indexterm significance="preferred"><primary>XUnionRectWithRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XUnionRectWithRegion</function></funcdef>
- <paramdef>XRectangle<parameter> *rectangle</parameter></paramdef>
- <paramdef>Region<parameter> src_region</parameter></paramdef>
- <paramdef>Region<parameter> dest_region_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>rectangle</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the rectangle.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>src_region</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the source region to be used.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dest_region_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the destination region.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XUnionRectWithRegion</function>
-function updates the destination region from a union of the specified rectangle
-and the specified source region.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To subtract two regions, use
-<function>XSubtractRegion</function>.
-<indexterm significance="preferred"><primary>XSubtractRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XSubtractRegion</function></funcdef>
- <paramdef>Regionsra,srb,<parameter> dr_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>sra</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>srb</emphasis>
- </term>
- <listitem>
- <para>
-Specify the two regions with which you want to perform the computation.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dr_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the result of the computation.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSubtractRegion</function>
-function subtracts srb from sra and stores the results in dr_return.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To calculate the difference between the union and intersection
-of two regions, use
-<function>XXorRegion</function>.
-<indexterm significance="preferred"><primary>XXorRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XXorRegion</function></funcdef>
- <paramdef>Regionsra,srb,<parameter> dr_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>sra</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>srb</emphasis>
- </term>
- <listitem>
- <para>
-Specify the two regions with which you want to perform the computation.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>dr_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the result of the computation.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-</para>
-</sect2>
-<sect2 id="Determining_if_Regions_Are_Empty_or_Equal">
-<title>Determining if Regions Are Empty or Equal</title>
-<!-- .XS -->
-<!-- (SN Determining if Regions Are Empty or Equal -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To determine if the specified region is empty, use
-<function>XEmptyRegion</function>.
-<indexterm significance="preferred"><primary>XEmptyRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XEmptyRegion</function></funcdef>
- <paramdef>Region<parameter> r</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>r</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the region.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XEmptyRegion</function>
-function returns
-<symbol>True</symbol>
-if the region is empty.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To determine if two regions have the same offset, size, and shape, use
-<function>XEqualRegion</function>.
-<indexterm significance="preferred"><primary>XEqualRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XEqualRegion</function></funcdef>
- <paramdef>Regionr1,<parameter> r2</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>r1</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>r2</emphasis>
- </term>
- <listitem>
- <para>
-Specify the two regions.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XEqualRegion</function>
-function returns
-<symbol>True</symbol>
-if the two regions have the same offset, size, and shape.
-</para>
-</sect2>
-<sect2 id="Locating_a_Point_or_a_Rectangle_in_a_Region">
-<title>Locating a Point or a Rectangle in a Region</title>
-<!-- .XS -->
-<!-- (SN Locating a Point or a Rectangle in a Region -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-To determine if a specified point resides in a specified region, use
-<function>XPointInRegion</function>.
-<indexterm significance="preferred"><primary>XPointInRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Bool <function>XPointInRegion</function></funcdef>
- <paramdef>Region<parameter> r</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>r</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the region.
-<!-- .ds Xy , which define the point -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XPointInRegion</function>
-function returns
-<symbol>True</symbol>
-if the point (x, y) is contained in the region r.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To determine if a specified rectangle is inside a region, use
-<function>XRectInRegion</function>.
-<indexterm significance="preferred"><primary>XRectInRegion</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XRectInRegion</function></funcdef>
- <paramdef>Region<parameter> r</parameter></paramdef>
- <paramdef>intx,<parameter> y</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>r</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the region.
-<!-- .ds Xy , which define the coordinates of the upper-left corner of the rectangle -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates(Xy.
-<!-- .ds Wh , which define the rectangle -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height(Wh.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XRectInRegion</function>
-function returns
-<symbol>RectangleIn</symbol>
-if the rectangle is entirely in the specified region,
-<symbol>RectangleOut</symbol>
-if the rectangle is entirely out of the specified region,
-and
-<symbol>RectanglePart</symbol>
-if the rectangle is partially in the specified region.
-</para>
-</sect2>
-</sect1>
-<sect1 id="Using_Cut_Buffers">
-<title>Using Cut Buffers</title>
-<!-- .XS -->
-<!-- (SN Using Cut Buffers -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-<indexterm><primary>Cut Buffers</primary></indexterm>
-Xlib provides functions to manipulate cut buffers,
-a very simple form of cut-and-paste inter-client communication.
-Selections are a much more powerful and useful mechanism for
-interchanging data between clients (see section 4.5)
-and generally should be used instead of cut buffers.
-</para>
-<para>
-<!-- .LP -->
-Cut buffers are implemented as properties on the first root window
-of the display.
-The buffers can only contain text, in the STRING encoding.
-The text encoding is not changed by Xlib when fetching or storing.
-Eight buffers are provided
-and can be accessed as a ring or as explicit buffers (numbered 0 through 7).
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To store data in cut buffer 0, use
-<function>XStoreBytes</function>.
-<indexterm significance="preferred"><primary>XStoreBytes</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XStoreBytes</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *bytes</parameter></paramdef>
- <paramdef>int<parameter> nbytes</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the bytes, which are not necessarily ASCII or null-terminated.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nbytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes to be stored.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The data can have embedded null characters
-and need not be null-terminated.
-The cut buffer's contents can be retrieved later by
-any client calling
-<function>XFetchBytes</function>.
-</para>
-<para>
-<!-- .LP -->
-<function>XStoreBytes</function>
-can generate a
-<errorname>BadAlloc</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To store data in a specified cut buffer, use
-<function>XStoreBuffer</function>.
-<indexterm significance="preferred"><primary>XStoreBuffer</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XStoreBuffer</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *bytes</parameter></paramdef>
- <paramdef>int<parameter> nbytes</parameter></paramdef>
- <paramdef>int<parameter> buffer</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the bytes, which are not necessarily ASCII or null-terminated.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nbytes</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes to be stored.
-<!-- .ds Fn in which you want to store the bytes -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>buffer</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the buffer (Fn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If an invalid buffer is specified, the call has no effect.
-The data can have embedded null characters
-and need not be null-terminated.
-</para>
-<para>
-<!-- .LP -->
-<function>XStoreBuffer</function>
-can generate a
-<errorname>BadAlloc</errorname>
-error.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To return data from cut buffer 0, use
-<function>XFetchBytes</function>.
-<indexterm significance="preferred"><primary>XFetchBytes</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XFetchBytes</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> *nbytes_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nbytes_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of bytes in the buffer.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFetchBytes</function>
-function
-returns the number of bytes in the nbytes_return argument,
-if the buffer contains data.
-Otherwise, the function
-returns NULL and sets nbytes to 0.
-The appropriate amount of storage is allocated and the pointer returned.
-The client must free this storage when finished with it by calling
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To return data from a specified cut buffer, use
-<function>XFetchBuffer</function>.
-<indexterm significance="preferred"><primary>XFetchBuffer</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>char *<function>XFetchBuffer</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> *nbytes_return</parameter></paramdef>
- <paramdef>int<parameter> buffer</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nbytes_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of bytes in the buffer.
-<!-- .ds Fn from which you want the stored data returned -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>buffer</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the buffer (Fn.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XFetchBuffer</function>
-function returns zero to the nbytes_return argument
-if there is no data in the buffer or if an invalid
-buffer is specified.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To rotate the cut buffers, use
-<function>XRotateBuffers</function>.
-<indexterm significance="preferred"><primary>XRotateBuffers</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XRotateBuffers</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> rotate</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>rotate</emphasis>
- </term>
- <listitem>
- <para>
-Specifies how much to rotate the cut buffers.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XRotateBuffers</function>
-function rotates the cut
-buffers, such that buffer 0 becomes buffer n,
-buffer 1 becomes n + 1 mod 8, and so on.
-This cut buffer numbering is global to the display.
-Note that
-<function>XRotateBuffers</function>
-generates
-<errorname>BadMatch</errorname>
-errors if any of the eight buffers have not been created.
-</para>
-</sect1>
-<sect1 id="Determining_the_Appropriate_Visual_Type">
-<title>Determining the Appropriate Visual Type</title>
-<!-- .XS -->
-<!-- (SN Determining the Appropriate Visual Type -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-A single display can support multiple screens.
-Each screen can have several different visual types supported
-at different depths.
-You can use the functions described in this section to determine
-which visual to use for your application.
-</para>
-<para>
-<!-- .LP -->
-The functions in this section use the visual information masks and the
-<structname>XVisualInfo</structname>
-structure,
-which is defined in
-<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
-<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-and contains:
-<!-- .sM -->
-</para>
-<!-- .LP -->
-<literallayout class="monospaced">
-
-/* Visual information mask bits */
-
-
-#define VisualNoMask 0x0
-#define VisualIDMask 0x1
-#define VisualScreenMask 0x2
-#define VisualDepthMask 0x4
-#define VisualClassMask 0x8
-#define VisualRedMaskMask 0x10
-#define VisualGreenMaskMask 0x20
-#define VisualBlueMaskMask 0x40
-#define VisualColormapSizeMask 0x80
-#define VisualBitsPerRGBMask 0x100
-#define VisualAllMask 0x1FF
-
-</literallayout>
-
-<literallayout class="monospaced">
-<!-- .TA .5i 3i -->
-<!-- .ta .5i 3i -->
-/* Values */
-
-typedef struct {
- Visual *visual;
- VisualID visualid;
- int screen;
- unsigned int depth;
- int class;
- unsigned long red_mask;
- unsigned long green_mask;
- unsigned long blue_mask;
- int colormap_size;
- int bits_per_rgb;
-} XVisualInfo;
-</literallayout>
-
-<para>
-<!-- .LP -->
-<!-- .eM -->
-To obtain a list of visual information structures that match a specified
-template, use
-<function>XGetVisualInfo</function>.
-<indexterm significance="preferred"><primary>XGetVisualInfo</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XVisualInfo *<function>XGetVisualInfo</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>long<parameter> vinfo_mask</parameter></paramdef>
- <paramdef>XVisualInfo<parameter> *vinfo_template</parameter></paramdef>
- <paramdef>int<parameter> *nitems_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>vinfo_mask</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the visual mask value.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>vinfo_template</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the visual attributes that are to be used in matching the visual
-structures.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>nitems_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the number of matching visual structures.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetVisualInfo</function>
-function returns a list of visual structures that have attributes
-equal to the attributes specified by vinfo_template.
-If no visual structures match the template using the specified vinfo_mask,
-<function>XGetVisualInfo</function>
-returns a NULL.
-To free the data returned by this function, use
-<function>XFree</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain the visual information that matches the specified depth and
-class of the screen, use
-<function>XMatchVisualInfo</function>.
-<indexterm significance="preferred"><primary>XMatchVisualInfo</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Status <function>XMatchVisualInfo</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>int<parameter> screen</parameter></paramdef>
- <paramdef>int<parameter> depth</parameter></paramdef>
- <paramdef>int<parameter> class</parameter></paramdef>
- <paramdef>XVisualInfo<parameter> *vinfo_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>screen</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the screen.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>depth</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the depth of the screen.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>class</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the class of the screen.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>vinfo_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the matched visual information.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XMatchVisualInfo</function>
-function returns the visual information for a visual that matches the specified
-depth and class for a screen.
-Because multiple visuals that match the specified depth and class can exist,
-the exact visual chosen is undefined.
-If a visual is found,
-<function>XMatchVisualInfo</function>
-returns nonzero and the information on the visual to vinfo_return.
-Otherwise, when a visual is not found,
-<function>XMatchVisualInfo</function>
-returns zero.
-</para>
-</sect1>
-<sect1 id="Manipulating_Images">
-<title>Manipulating Images</title>
-<!-- .XS -->
-<!-- (SN Manipulating Images -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides several functions that perform basic operations on images.
-All operations on images are defined using an
-<structname>XImage</structname>
-structure,
-as defined in
-<filename class="headerfile">&lt;X11/Xlib.h&gt;</filename>.
-<indexterm type="file"><primary><filename class="headerfile">X11/Xlib.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xlib.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xlib.h&gt;</filename></secondary></indexterm>
-Because the number of different types of image formats can be very large,
-this hides details of image storage properly from applications.
-</para>
-<para>
-<!-- .LP -->
-This section describes the functions for generic operations on images.
-Manufacturers can provide very fast implementations of these for the
-formats frequently encountered on their hardware.
-These functions are neither sufficient nor desirable to use for general image
-processing.
-Rather, they are here to provide minimal functions on screen format
-images.
-The basic operations for getting and putting images are
-<function>XGetImage</function>
-and
-<function>XPutImage</function>.
-</para>
-<para>
-<!-- .LP -->
-Note that no functions have been defined, as yet, to read and write images
-to and from disk files.
-</para>
-<para>
-<!-- .LP -->
-The
-<structname>XImage</structname>
-structure describes an image as it exists in the client's memory.
-The user can request that some of the members such as height, width,
-and xoffset be changed when the image is sent to the server.
-Note that bytes_per_line in concert with offset can be used to
-extract a subset of the image.
-Other members (for example, byte order, bitmap_unit, and so forth)
-are characteristics of both the image and the server.
-If these members
-differ between the image and the server,
-<function>XPutImage</function>
-makes the appropriate conversions.
-The first byte of the first line of
-plane n must be located at the address (data + (n * height * bytes_per_line)).
-For a description of the
-<structname>XImage</structname>
-structure,
-see section 8.7.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To allocate an
-<structname>XImage</structname>
-structure and initialize it with image format values from a display, use
-<function>XCreateImage</function>.
-<indexterm significance="preferred"><primary>XCreateImage</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XImage *<function>XCreateImage</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Visual<parameter> *visual</parameter></paramdef>
- <paramdef>unsignedint<parameter> depth</parameter></paramdef>
- <paramdef>int<parameter> format</parameter></paramdef>
- <paramdef>int<parameter> offset</parameter></paramdef>
- <paramdef>char<parameter> *data</parameter></paramdef>
- <paramdef>unsignedint<parameter> width</parameter></paramdef>
- <paramdef>unsignedint<parameter> height</parameter></paramdef>
- <paramdef>int<parameter> bitmap_pad</parameter></paramdef>
- <paramdef>int<parameter> bytes_per_line</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>visual</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the
-<structname>Visual</structname>
-structure.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>depth</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the depth of the image.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>format</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the format for the image.
-You can pass
-<symbol>XYBitmap</symbol>,
-<symbol>XYPixmap</symbol>,
-or
-<symbol>ZPixmap</symbol>.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>offset</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of pixels to ignore at the beginning of the scanline.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the image data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the width of the image, in pixels.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the height of the image, in pixels.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bitmap_pad</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the quantum of a scanline (8, 16, or 32).
-In other words, the start of one scanline is separated in client memory from
-the start of the next scanline by an integer multiple of this many bits.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bytes_per_line</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the number of bytes in the client image between
-the start of one scanline and the start of the next.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreateImage</function>
-function allocates the memory needed for an
-<structname>XImage</structname>
-structure for the
-specified display but does not allocate space for the image itself.
-Rather, it initializes the structure byte-order, bit-order, and bitmap-unit
-values from the display and returns a pointer to the
-<structname>XImage</structname>
-structure.
-The red, green, and blue mask values are defined for Z format images only
-and are derived from the
-<structname>Visual</structname>
-structure passed in.
-Other values also are passed in.
-The offset permits the rapid displaying of the image without requiring each
-scanline to be shifted into position.
-If you pass a zero value in bytes_per_line,
-Xlib assumes that the scanlines are contiguous
-in memory and calculates the value of bytes_per_line itself.
-</para>
-<para>
-<!-- .LP -->
-Note that when the image is created using
-<function>XCreateImage</function>,
-<function>XGetImage</function>,
-or
-<function>XSubImage</function>,
-the destroy procedure that the
-<function>XDestroyImage</function>
-function calls frees both the image structure
-and the data pointed to by the image structure.
-</para>
-<para>
-<!-- .LP -->
-The basic functions used to get a pixel, set a pixel, create a subimage,
-and add a constant value to an image are defined in the image object.
-The functions in this section are really macro invocations of the functions
-in the image object and are defined in
-<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>.
-<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To obtain a pixel value in an image, use
-<function>XGetPixel</function>.
-<indexterm significance="preferred"><primary>XGetPixel</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>unsigned long <function>XGetPixel</function></funcdef>
- <paramdef>XImage<parameter> *ximage</parameter></paramdef>
- <paramdef>int<parameter> x</parameter></paramdef>
- <paramdef>int<parameter> y</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ximage</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the image.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XGetPixel</function>
-function returns the specified pixel from the named image.
-The pixel value is returned in normalized format (that is,
-the least significant byte of the long is the least significant byte
-of the pixel).
-The image must contain the x and y coordinates.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To set a pixel value in an image, use
-<function>XPutPixel</function>.
-<indexterm significance="preferred"><primary>XPutPixel</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XPutPixel</function></funcdef>
- <paramdef>XImage<parameter> *ximage</parameter></paramdef>
- <paramdef>int<parameter> x</parameter></paramdef>
- <paramdef>int<parameter> y</parameter></paramdef>
- <paramdef>unsignedlong<parameter> pixel</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ximage</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the image.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>pixel</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the new pixel value.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XPutPixel</function>
-function overwrites the pixel in the named image with the specified pixel value.
-The input pixel value must be in normalized format
-(that is, the least significant byte of the long is the least significant
-byte of the pixel).
-The image must contain the x and y coordinates.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create a subimage, use
-<function>XSubImage</function>.
-<indexterm significance="preferred"><primary>XSubImage</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>XImage *<function>XSubImage</function></funcdef>
- <paramdef>XImage<parameter> *ximage</parameter></paramdef>
- <paramdef>int<parameter> x</parameter></paramdef>
- <paramdef>int<parameter> y</parameter></paramdef>
- <paramdef>unsignedint<parameter> subimage_width</parameter></paramdef>
- <paramdef>unsignedint<parameter> subimage_height</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ximage</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the image.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y</emphasis>
- </term>
- <listitem>
- <para>
-Specify the x and y coordinates.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>subimage_width</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the width of the new subimage, in pixels.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>subimage_height</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the height of the new subimage, in pixels.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XSubImage</function>
-function creates a new image that is a subsection of an existing one.
-It allocates the memory necessary for the new
-<structname>XImage</structname>
-structure
-and returns a pointer to the new image.
-The data is copied from the source image,
-and the image must contain the rectangle defined by x, y, subimage_width,
-and subimage_height.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To increment each pixel in an image by a constant value, use
-<function>XAddPixel</function>.
-<indexterm significance="preferred"><primary>XAddPixel</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XAddPixel</function></funcdef>
- <paramdef>XImage<parameter> *ximage</parameter></paramdef>
- <paramdef>long<parameter> value</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ximage</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the image.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>value</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the constant value that is to be added.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XAddPixel</function>
-function adds a constant value to every pixel in an image.
-It is useful when you have a base pixel value from allocating
-color resources and need to manipulate the image to that form.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To deallocate the memory allocated in a previous call to
-<function>XCreateImage</function>,
-use
-<function>XDestroyImage</function>.
-<indexterm significance="preferred"><primary>XDestroyImage</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef><function>XDestroyImage</function></funcdef>
- <paramdef>XImage *<parameter>ximage</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>ximage</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the image.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDestroyImage</function>
-function deallocates the memory associated with the
-<structname>XImage</structname>
-structure.
-</para>
-<para>
-<!-- .LP -->
-Note that when the image is created using
-<function>XCreateImage</function>,
-<function>XGetImage</function>,
-or
-<function>XSubImage</function>,
-the destroy procedure that this macro calls
-frees both the image structure and the data pointed to by the image structure.
-</para>
-</sect1>
-<sect1 id="Manipulating_Bitmaps">
-<title>Manipulating Bitmaps</title>
-<!-- .XS -->
-<!-- (SN Manipulating Bitmaps -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-Xlib provides functions that you can use to read a bitmap from a file,
-save a bitmap to a file, or create a bitmap.
-This section describes those functions that transfer bitmaps to and
-from the client's file system, thus allowing their reuse in a later
-connection (for example, from an entirely different client or to a
-different display or server).
-</para>
-<para>
-<!-- .LP -->
-The X version 11 bitmap file format is:
-</para>
-<para>
-<!-- .LP -->
-<!-- .sM -->
-<literallayout class="monospaced">
-#define <emphasis remap='I'>name</emphasis>_width <emphasis remap='I'>width</emphasis>
-#define <emphasis remap='I'>name</emphasis>_height <emphasis remap='I'>height</emphasis>
-#define <emphasis remap='I'>name</emphasis>_x_hot <emphasis remap='I'>x</emphasis>
-#define <emphasis remap='I'>name</emphasis>_y_hot <emphasis remap='I'>y</emphasis>
-static unsigned char <emphasis remap='I'>name</emphasis>_bits[] = { 0x<emphasis remap='I'>NN</emphasis>,... }
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The lines for the variables ending with _x_hot and _y_hot suffixes are optional
-because they are present only if a hotspot has been defined for this bitmap.
-The lines for the other variables are required.
-The word ``unsigned'' is optional;
-that is, the type of the _bits array can be ``char'' or ``unsigned char''.
-The _bits array must be large enough to contain the size bitmap.
-The bitmap unit is 8.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To read a bitmap from a file and store it in a pixmap, use
-<function>XReadBitmapFile</function>.
-<indexterm significance="preferred"><primary>XReadBitmapFile</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XReadBitmapFile</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>char<parameter> *filename</parameter></paramdef>
- <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
- <paramdef>Pixmap<parameter> *bitmap_return</parameter></paramdef>
- <paramdef>int*x_hot_return,<parameter> *y_hot_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Dr \ that indicates the screen -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable(Dr.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>filename</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the file name to use.
-The format of the file name is operating-system dependent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the width and height values of the read in bitmap file.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bitmap_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the bitmap that is created.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x_hot_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y_hot_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the hotspot coordinates.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XReadBitmapFile</function>
-function reads in a file containing a bitmap.
-The file is parsed in the encoding of the current locale.
-The ability to read other than the standard format
-is implementation-dependent.
-If the file cannot be opened,
-<function>XReadBitmapFile</function>
-returns
-<returnvalue>BitmapOpenFailed</returnvalue>.
-If the file can be opened but does not contain valid bitmap data,
-it returns
-<returnvalue>BitmapFileInvalid</returnvalue>.
-If insufficient working storage is allocated,
-it returns
-<returnvalue>BitmapNoMemory</returnvalue>.
-If the file is readable and valid,
-it returns
-<returnvalue>BitmapSuccess</returnvalue>.
-</para>
-<para>
-<!-- .LP -->
-<function>XReadBitmapFile</function>
-returns the bitmap's height and width, as read
-from the file, to width_return and height_return.
-It then creates a pixmap of the appropriate size,
-reads the bitmap data from the file into the pixmap,
-and assigns the pixmap to the caller's variable bitmap.
-The caller must free the bitmap using
-<function>XFreePixmap</function>
-when finished.
-If <emphasis remap='I'>name</emphasis>_x_hot and <emphasis remap='I'>name</emphasis>_y_hot exist,
-<function>XReadBitmapFile</function>
-returns them to x_hot_return and y_hot_return;
-otherwise, it returns &minus;1,&minus;1.
-</para>
-<para>
-<!-- .LP -->
-<function>XReadBitmapFile</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadDrawable</errorname>,
-and
-<errorname>BadGC</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To read a bitmap from a file and return it as data, use
-<function>XReadBitmapFileData</function>.
-<indexterm significance="preferred"><primary>XReadBitmapFileData</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XReadBitmapFileData</function></funcdef>
- <paramdef>char<parameter> *filename</parameter></paramdef>
- <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
- <paramdef>unsignedchar<parameter> *data_return</parameter></paramdef>
- <paramdef>int*x_hot_return,<parameter> *y_hot_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>filename</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the file name to use.
-The format of the file name is operating-system dependent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the width and height values of the read in bitmap file.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>data_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the bitmap data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x_hot_return</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y_hot_return</emphasis>
- </term>
- <listitem>
- <para>
-Return the hotspot coordinates.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XReadBitmapFileData</function>
-function reads in a file containing a bitmap, in the same manner as
-<function>XReadBitmapFile</function>,
-but returns the data directly rather than creating a pixmap in the server.
-The bitmap data is returned in data_return; the client must free this
-storage when finished with it by calling
-<function>XFree</function>.
-The status and other return values are the same as for
-<function>XReadBitmapFile</function>.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To write out a bitmap from a pixmap to a file, use
-<function>XWriteBitmapFile</function>.
-<indexterm significance="preferred"><primary>XWriteBitmapFile</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XWriteBitmapFile</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>char<parameter> *filename</parameter></paramdef>
- <paramdef>Pixmap<parameter> bitmap</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>intx_hot,<parameter> y_hot</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>filename</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the file name to use.
-The format of the file name is operating-system dependent.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bitmap</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the bitmap.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>x_hot</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>y_hot</emphasis>
- </term>
- <listitem>
- <para>
-Specify where to place the hotspot coordinates (or &minus;1,&minus;1 if none are present)
-in the file.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XWriteBitmapFile</function>
-function writes a bitmap out to a file in the X Version 11 format.
-The name used in the output file is derived from the file name
-by deleting the directory prefix.
-The file is written in the encoding of the current locale.
-If the file cannot be opened for writing,
-it returns
-<returnvalue>BitmapOpenFailed</returnvalue>.
-If insufficient memory is allocated,
-<function>XWriteBitmapFile</function>
-returns
-<returnvalue>BitmapNoMemory</returnvalue>;
-otherwise, on no error,
-it returns
-<returnvalue>BitmapSuccess</returnvalue>.
-If x_hot and y_hot are not &minus;1, &minus;1,
-<function>XWriteBitmapFile</function>
-writes them out as the hotspot coordinates for the bitmap.
-</para>
-<para>
-<!-- .LP -->
-<function>XWriteBitmapFile</function>
-can generate
-<errorname>BadDrawable</errorname>
-and
-<errorname>BadMatch</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create a pixmap and then store bitmap-format data into it, use
-<function>XCreatePixmapFromBitmapData</function>.
-<indexterm significance="preferred"><primary>XCreatePixmapFromBitmapData</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Pixmap <function>XCreatePixmapFromBitmapData</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>char<parameter> *data</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
- <paramdef>unsignedlongfg,<parameter> bg</parameter></paramdef>
- <paramdef>unsignedint<parameter> depth</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Dr \ that indicates the screen -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable(Dr.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the data in bitmap format.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>fg</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>bg</emphasis>
- </term>
- <listitem>
- <para>
-Specify the foreground and background pixel values to use.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>depth</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the depth of the pixmap.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreatePixmapFromBitmapData</function>
-function creates a pixmap of the given depth and then does a bitmap-format
-<function>XPutImage</function>
-of the data into it.
-The depth must be supported by the screen of the specified drawable,
-or a
-<errorname>BadMatch</errorname>
-error results.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreatePixmapFromBitmapData</function>
-can generate
-<errorname>BadAlloc</errorname>,
-<errorname>BadDrawable</errorname>,
-<errorname>BadGC</errorname>,
-and
-<errorname>BadValue</errorname>
-errors.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To include a bitmap written out by
-<function>XWriteBitmapFile</function>
-<indexterm><primary>XWriteBitmapFile</primary></indexterm>
-in a program directly, as opposed to reading it in every time at run time, use
-<function>XCreateBitmapFromData</function>.
-<indexterm significance="preferred"><primary>XCreateBitmapFromData</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>Pixmap <function>XCreateBitmapFromData</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>Drawable<parameter> d</parameter></paramdef>
- <paramdef>char<parameter> *data</parameter></paramdef>
- <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
-<!-- .ds Dr \ that indicates the screen -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>d</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the drawable(Dr.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the location of the bitmap data.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>width</emphasis>
- </term>
- <listitem>
- <para>
-<!-- .br -->
-<!-- .ns -->
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>height</emphasis>
- </term>
- <listitem>
- <para>
-Specify the width and height.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XCreateBitmapFromData</function>
-function allows you to include in your C program (using
-<code>#include</code>)
-a bitmap file that was written out by
-<function>XWriteBitmapFile</function>
-(X version 11 format only) without reading in the bitmap file.
-The following example creates a gray bitmap:
-</para>
-<para>
-<!-- .LP -->
-<literallayout class="monospaced">
-#include "gray.bitmap"
-<!-- .sp 6p -->
-Pixmap bitmap;
-bitmap = XCreateBitmapFromData(display, window, gray_bits, gray_width, gray_height);
-</literallayout>
-</para>
-<para>
-<!-- .LP -->
-If insufficient working storage was allocated,
-<function>XCreateBitmapFromData</function>
-returns
-<symbol>None</symbol>.
-It is your responsibility to free the
-bitmap using
-<function>XFreePixmap</function>
-when finished.
-</para>
-<para>
-<!-- .LP -->
-<function>XCreateBitmapFromData</function>
-can generate
-<errorname>BadAlloc</errorname>
-and
-<errorname>BadGC</errorname>
-errors.
-</para>
-</sect1>
-<sect1 id="Using_the_Context_Manager">
-<title>Using the Context Manager</title>
-<!-- .XS -->
-<!-- (SN Using the Context Manager -->
-<!-- .XE -->
-<para>
-<!-- .LP -->
-The context manager provides a way of associating data with an X resource ID
-(mostly typically a window) in your program.
-Note that this is local to your program;
-the data is not stored in the server on a property list.
-Any amount of data in any number of pieces can be associated with a
-resource ID,
-and each piece of data has a type associated with it.
-The context manager requires knowledge of the resource ID
-and type to store or retrieve data.
-</para>
-<para>
-<!-- .LP -->
-Essentially, the context manager can be viewed as a two-dimensional,
-sparse array: one dimension is subscripted by the X resource ID
-and the other by a context type field.
-Each entry in the array contains a pointer to the data.
-Xlib provides context management functions with which you can
-save data values, get data values, delete entries, and create a unique
-context type.
-The symbols used are in
-<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>.
-<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
-<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To save a data value that corresponds to a resource ID and context type, use
-<function>XSaveContext</function>.
-<indexterm significance="preferred"><primary>XSaveContext</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XSaveContext</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XID<parameter> rid</parameter></paramdef>
- <paramdef>XContext<parameter> context</parameter></paramdef>
- <paramdef>XPointer<parameter> data</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>rid</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource ID with which the data is associated.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>context</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the context type to which the data belongs.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>data</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the data to be associated with the window and type.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-If an entry with the specified resource ID and type already exists,
-<function>XSaveContext</function>
-overrides it with the specified context.
-The
-<function>XSaveContext</function>
-function returns a nonzero error code if an error has occurred
-and zero otherwise.
-Possible errors are
-<symbol>XCNOMEM</symbol>
-(out of memory).
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To get the data associated with a resource ID and type, use
-<function>XFindContext</function>.
-<indexterm significance="preferred"><primary>XFindContext</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XFindContext</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XID<parameter> rid</parameter></paramdef>
- <paramdef>XContext<parameter> context</parameter></paramdef>
- <paramdef>XPointer<parameter> *data_return</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>rid</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource ID with which the data is associated.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>context</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the context type to which the data belongs.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>data_return</emphasis>
- </term>
- <listitem>
- <para>
-Returns the data.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-Because it is a return value,
-the data is a pointer.
-The
-<function>XFindContext</function>
-function returns a nonzero error code if an error has occurred
-and zero otherwise.
-Possible errors are
-<symbol>XCNOENT</symbol>
-(context-not-found).
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To delete an entry for a given resource ID and type, use
-<function>XDeleteContext</function>.
-<indexterm significance="preferred"><primary>XDeleteContext</primary></indexterm>
-<!-- .sM -->
-<funcsynopsis>
-<funcprototype>
- <funcdef>int <function>XDeleteContext</function></funcdef>
- <paramdef>Display<parameter> *display</parameter></paramdef>
- <paramdef>XID<parameter> rid</parameter></paramdef>
- <paramdef>XContext<parameter> context</parameter></paramdef>
-</funcprototype>
-</funcsynopsis>
-<!-- .FN -->
-<variablelist>
- <varlistentry>
- <term>
- <emphasis remap='I'>display</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the connection to the X server.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>rid</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the resource ID with which the data is associated.
- </para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term>
- <emphasis remap='I'>context</emphasis>
- </term>
- <listitem>
- <para>
-Specifies the context type to which the data belongs.
- </para>
- </listitem>
- </varlistentry>
-</variablelist>
-</para>
-<para>
-<!-- .LP -->
-<!-- .eM -->
-The
-<function>XDeleteContext</function>
-function deletes the entry for the given resource ID
-and type from the data structure.
-This function returns the same error codes that
-<function>XFindContext</function>
-returns if called with the same arguments.
-<function>XDeleteContext</function>
-does not free the data whose address was saved.
-</para>
-<para>
-<!-- .LP -->
-<!-- .sp -->
-To create a unique context type that may be used in subsequent calls to
-<function>XSaveContext</function>
-and
-<function>XFindContext</function>,
-use
-<function>XUniqueContext</function>.
-</para>
-<para>XContext XuniqueContext()</para>
-
-</sect1>
-</chapter>
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
+ "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd">
+<chapter id="application_utility_functions">
+<title>Application Utility Functions</title>
+<!-- .sp 2 -->
+<!-- .nr H1 16 -->
+<!-- .nr H2 0 -->
+<!-- .nr H3 0 -->
+<!-- .nr H4 0 -->
+<!-- .nr H5 0 -->
+<!-- .na -->
+<para>
+<!-- .LP -->
+<!-- .XS -->
+<!-- Chapter 16: Application Utility Functions -->
+<!-- .XE -->
+Once you have initialized the X system,
+you can use the Xlib utility functions to:
+</para>
+<itemizedlist>
+ <listitem>
+ <para>
+Use keyboard utility functions
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Use Latin-1 keyboard event functions
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Allocate permanent storage
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Parse the window geometry
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Manipulate regions
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Use cut buffers
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Determine the appropriate visual type
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Manipulate images
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Manipulate bitmaps
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Use the context manager
+ </para>
+ </listitem>
+</itemizedlist>
+<para>
+<!-- .LP -->
+As a group,
+the functions discussed in this chapter provide the functionality that
+is frequently needed and that spans toolkits.
+Many of these functions do not generate actual protocol requests to the server.
+</para>
+<sect1 id="Using_Keyboard_Utility_Functions">
+<title>Using Keyboard Utility Functions</title>
+<!-- .XS -->
+<!-- (SN Using Keyboard Utility Functions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+This section discusses mapping between KeyCodes and KeySyms,
+classifying KeySyms, and mapping between KeySyms and string names.
+The first three functions in this section operate on a cached copy of the
+server keyboard mapping.
+The first four KeySyms for each KeyCode
+are modified according to the rules given in section 12.7.
+To obtain the untransformed KeySyms defined for a key,
+use the functions described in section 12.7.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain a KeySym for the KeyCode of an event, use
+<function>XLookupKeysym</function>.
+<indexterm significance="preferred"><primary>XLookupKeysym</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xlookupkeysym'>
+<funcprototype>
+ <funcdef>KeySym <function>XLookupKeysym</function></funcdef>
+ <paramdef>XKeyEvent<parameter> *key_event</parameter></paramdef>
+ <paramdef>int<parameter> index</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>key_event</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<symbol>KeyPress</symbol>
+or
+<symbol>KeyRelease</symbol>
+event.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>index</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the index into the KeySyms list for the event's KeyCode.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XLookupKeysym</function>
+function uses a given keyboard event and the index you specified to return
+the KeySym from the list that corresponds to the KeyCode member in the
+<type>XKeyPressedEvent</type>
+or
+<type>XKeyReleasedEvent</type>
+structure.
+If no KeySym is defined for the KeyCode of the event,
+<function>XLookupKeysym</function>
+returns
+<symbol>NoSymbol</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain a KeySym for a specific KeyCode, use
+<function>XKeycodeToKeysym</function>.
+<indexterm significance="preferred"><primary>XKeycodeToKeysym</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xkeycodetokeysym'>
+<funcprototype>
+ <funcdef>KeySym <function>XKeycodeToKeysym</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>KeyCode<parameter> keycode</parameter></paramdef>
+ <paramdef>int<parameter> index</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keycode</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeyCode.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>index</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the element of KeyCode vector.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XKeycodeToKeysym</function>
+function uses internal Xlib tables
+and returns the KeySym defined for the specified KeyCode and
+the element of the KeyCode vector.
+If no symbol is defined,
+<function>XKeycodeToKeysym</function>
+returns
+<symbol>NoSymbol</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain a KeyCode for a key having a specific KeySym, use
+<function>XKeysymToKeycode</function>.
+<indexterm significance="preferred"><primary>XKeysymToKeycode</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xkeysymtokeycode'>
+<funcprototype>
+ <funcdef>KeyCode <function>XKeysymToKeycode</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>KeySym<parameter> keysym</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeySym that is to be searched for.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If the specified KeySym is not defined for any KeyCode,
+<function>XKeysymToKeycode</function>
+returns zero.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+The mapping between KeyCodes and KeySyms is cached internal to Xlib.
+When this information is changed at the server, an Xlib function must
+be called to refresh the cache.
+To refresh the stored modifier and keymap information, use
+<function>XRefreshKeyboardMapping</function>.
+<indexterm significance="preferred"><primary>XRefreshKeyboardMapping</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrefreshkeyboardmapping'>
+<funcprototype>
+ <funcdef><function>XRefreshKeyboardMapping</function></funcdef>
+ <paramdef>XMappingEvent<parameter> *event_map</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_map</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the mapping event that is to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XRefreshKeyboardMapping</function>
+function refreshes the stored modifier and keymap information.
+You usually call this function when a
+<symbol>MappingNotify</symbol>
+event with a request member of
+<symbol>MappingKeyboard</symbol>
+or
+<symbol>MappingModifier</symbol>
+occurs.
+The result is to update Xlib's knowledge of the keyboard.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the uppercase and lowercase forms of a KeySym, use
+<function>XConvertCase</function>.
+<indexterm significance="preferred"><primary>XConvertCase</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xconvertcase'>
+<funcprototype>
+ <funcdef>void <function>XConvertCase</function></funcdef>
+ <paramdef>KeySym<parameter> keysym</parameter></paramdef>
+ <paramdef>KeySym<parameter> *lower_return</parameter></paramdef>
+ <paramdef>KeySym<parameter> *upper_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<!-- .ds Fn converted -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeySym that is to be (Fn.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>lower_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the lowercase form of keysym, or keysym.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>upper_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the uppercase form of keysym, or keysym.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XConvertCase</function>
+function returns the uppercase and lowercase forms of the specified Keysym,
+if the KeySym is subject to case conversion;
+otherwise, the specified KeySym is returned to both lower_return and
+upper_return.
+Support for conversion of other than Latin and Cyrillic KeySyms is
+implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+KeySyms have string names as well as numeric codes.
+To convert the name of the KeySym to the KeySym code, use
+<function>XStringToKeysym</function>.
+<indexterm significance="preferred"><primary>XStringToKeysym</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xstringtokeysym'>
+<funcprototype>
+ <funcdef>KeySym <function>XStringToKeysym</function></funcdef>
+ <paramdef>char<parameter> *string</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the name of the KeySym that is to be converted.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Standard KeySym names are obtained from
+<filename class="headerfile">&lt;X11/keysymdef.h&gt;</filename>
+<indexterm type="file"><primary><filename class="headerfile">X11/keysymdef.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/keysymdef.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/keysymdef.h&gt;</filename></secondary></indexterm>
+by removing the XK_ prefix from each name.
+KeySyms that are not part of the Xlib standard also may be obtained
+with this function.
+The set of KeySyms that are available in this manner
+and the mechanisms by which Xlib obtains them is implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+If the KeySym name is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+If the specified string does not match a valid KeySym,
+<function>XStringToKeysym</function>
+returns
+<symbol>NoSymbol</symbol>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To convert a KeySym code to the name of the KeySym, use
+<function>XKeysymToString</function>.
+<indexterm significance="preferred"><primary>XKeysymToString</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xkeysymtostring'>
+<funcprototype>
+ <funcdef>char *<function>XKeysymToString</function></funcdef>
+ <paramdef>KeySym<parameter> keysym</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<!-- .ds Fn converted -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeySym that is to be (Fn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The returned string is in a static area and must not be modified.
+The returned string is in the Host Portable Character Encoding.
+If the specified KeySym is not defined,
+<function>XKeysymToString</function>
+returns a NULL.
+</para>
+<sect2 id="KeySym_Classification_Macros">
+<title>KeySym Classification Macros</title>
+<!-- .XS -->
+<!-- (SN KeySym Classification Macros -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+You may want to test if a KeySym is, for example,
+on the keypad or on one of the function keys.
+You can use KeySym macros to perform the following tests.
+</para>
+<para>IsCursorKey(<emphasis remap='I'>keysym</emphasis>)</para>
+<!-- .FN -->
+<!-- .ds Fn tested -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeySym that is to be tested.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>IsCursorKey</primary></indexterm>
+Returns
+<symbol>True</symbol>
+if the specified KeySym is a cursor key.
+</para>
+<!-- .LP -->
+<!-- .sp -->
+<!-- .sM -->
+<para>IsFunctionKey(<emphasis remap='I'>keysym</emphasis>)</para>
+<!-- .FN -->
+<!-- .ds Fn tested -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeySym that is to be tested.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>IsFunctionKey</primary></indexterm>
+Returns
+<symbol>True</symbol>
+if the specified KeySym is a function key.
+</para>
+<!-- .LP -->
+<!-- .sp -->
+<!-- .sM -->
+<para>IsKeypadKey(<emphasis remap='I'>keysym</emphasis>)</para>
+<!-- .FN -->
+<!-- .ds Fn tested -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeySym that is to be (Fn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>IsKeypadKey</primary></indexterm>
+Returns
+<symbol>True</symbol>
+if the specified KeySym is a standard keypad key.
+</para>
+<!-- .LP -->
+<!-- .sp -->
+<!-- .sM -->
+<para>IsPrivateKeypadKey(<emphasis remap='I'>keysym</emphasis>)</para>
+
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeySym that is to be (Fn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>IsPrivateKeypadKey</primary></indexterm>
+Returns
+<symbol>True</symbol>
+if the specified KeySym is a vendor-private keypad key.
+</para>
+
+<!-- .LP -->
+<!-- .sp -->
+<!-- .sM -->
+<para>IsMiscFunctionKey(<emphasis remap='I'>keysym</emphasis>)</para>
+<!-- .FN -->
+<!-- .ds Fn tested -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeySym that is to be (Fn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>IsMiscFunctionKey</primary></indexterm>
+Returns
+<symbol>True</symbol>
+if the specified KeySym is a miscellaneous function key.
+</para>
+<!-- .LP -->
+<!-- .sp -->
+<!-- .sM -->
+<para>IsModifierKey(<emphasis remap='I'>keysym</emphasis>)</para>
+
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeySym that is to be tested.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>IsModifierKey</primary></indexterm>
+Returns
+<symbol>True</symbol>
+if the specified KeySym is a modifier key.
+</para>
+
+<para>IsPFKey(<emphasis remap='I'>keysym</emphasis>)</para>
+
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeySym that is to be tested.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<indexterm significance="preferred"><primary>IsPFKey</primary></indexterm>
+Returns
+<symbol>True</symbol>
+if the specified KeySym is a PF key.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Using_Latin_Keyboard_Event_Functions">
+<title>Using Latin-1 Keyboard Event Functions</title>
+<!-- .XS -->
+<!-- (SN Using Latin-1 Keyboard Event Functions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Chapter 13 describes internationalized text input facilities,
+but sometimes it is expedient to write an application that
+only deals with Latin-1 characters and ASCII controls,
+so Xlib provides a simple function for that purpose.
+<function>XLookupString</function>
+handles the standard modifier semantics described in section 12.7.
+This function does not use any of the input method facilities
+described in chapter 13 and does not depend on the current locale.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To map a key event to an ISO Latin-1 string, use
+<function>XLookupString</function>.
+<indexterm significance="preferred"><primary>XLookupString</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xlookupstring'>
+<funcprototype>
+ <funcdef>int <function>XLookupString</function></funcdef>
+ <paramdef>XKeyEvent<parameter> *event_struct</parameter></paramdef>
+ <paramdef>char<parameter> *buffer_return</parameter></paramdef>
+ <paramdef>int<parameter> bytes_buffer</parameter></paramdef>
+ <paramdef>KeySym<parameter> *keysym_return</parameter></paramdef>
+ <paramdef>XComposeStatus<parameter> *status_in_out</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>event_struct</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the key event structure to be used.
+You can pass
+<type>XKeyPressedEvent</type>
+or
+<type>XKeyReleasedEvent</type>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>buffer_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the translated characters.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bytes_buffer</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the length of the buffer.
+No more than bytes_buffer of translation are returned.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the KeySym computed from the event if this argument is not NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>status_in_out</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies or returns the
+<structname>XComposeStatus</structname>
+structure or NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XLookupString</function>
+function translates a key event to a KeySym and a string.
+The KeySym is obtained by using the standard interpretation of the
+<symbol>Shift</symbol>,
+<symbol>Lock</symbol>,
+group, and numlock modifiers as defined in the X Protocol specification.
+If the KeySym has been rebound (see
+<function>XRebindKeysym</function>),
+the bound string will be stored in the buffer.
+Otherwise, the KeySym is mapped, if possible, to an ISO Latin-1 character
+or (if the Control modifier is on) to an ASCII control character,
+and that character is stored in the buffer.
+<function>XLookupString</function>
+returns the number of characters that are stored in the buffer.
+</para>
+<para>
+<!-- .LP -->
+If present (non-NULL),
+the
+<structname>XComposeStatus</structname>
+structure records the state,
+which is private to Xlib,
+that needs preservation across calls to
+<function>XLookupString</function>
+to implement compose processing.
+The creation of
+<structname>XComposeStatus</structname>
+structures is implementation-dependent;
+a portable program must pass NULL for this argument.
+</para>
+<para>
+<!-- .LP -->
+<function>XLookupString</function>
+depends on the cached keyboard information mentioned in the
+previous section, so it is necessary to use
+<function>XRefreshKeyboardMapping</function>
+to keep this information up-to-date.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To rebind the meaning of a KeySym for
+<function>XLookupString</function>,
+use
+<function>XRebindKeysym</function>.
+<indexterm significance="preferred"><primary>XRebindKeysym</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrebindkeysym'>
+<funcprototype>
+ <funcdef><function>XRebindKeysym</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>KeySym<parameter> keysym</parameter></paramdef>
+ <paramdef>KeySym<parameter> list[&hairsp;]</parameter></paramdef>
+ <paramdef>int<parameter> mod_count</parameter></paramdef>
+ <paramdef>unsignedchar<parameter> *string</parameter></paramdef>
+ <paramdef>int<parameter> num_bytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Fn rebound -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>keysym</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeySym that is to be (Fn.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>list</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the KeySyms to be used as modifiers.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>mod_count</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of modifiers in the modifier list.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>string</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the string that is copied and will be returned by
+<function>XLookupString</function>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>num_bytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes in the string argument.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XRebindKeysym</function>
+function can be used to rebind the meaning of a KeySym for the client.
+It does not redefine any key in the X server but merely
+provides an easy way for long strings to be attached to keys.
+<function>XLookupString</function>
+returns this string when the appropriate set of
+modifier keys are pressed and when the KeySym would have been used for
+the translation.
+No text conversions are performed;
+the client is responsible for supplying appropriately encoded strings.
+Note that you can rebind a KeySym that may not exist.
+</para>
+</sect1>
+<sect1 id="Allocating_Permanent_Storage">
+<title>Allocating Permanent Storage</title>
+<!-- .XS -->
+<!-- (SN Allocating Permanent Storage -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To allocate some memory you will never give back, use
+<function>Xpermalloc</function>.
+<indexterm significance="preferred"><primary>Xpermalloc</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xpermalloc'>
+<funcprototype>
+ <funcdef>char *<function>Xpermalloc</function></funcdef>
+ <paramdef>unsignedint<parameter> size</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>Xpermalloc</function>
+function allocates storage that can never be freed for the life of the
+program. The memory is allocated with alignment for the C type double.
+This function may provide some performance and space savings over
+the standard operating system memory allocator.
+</para>
+</sect1>
+<sect1 id="Parsing_the_Window_Geometry">
+<title>Parsing the Window Geometry</title>
+<!-- .XS -->
+<!-- (SN Parsing the Window Geometry -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To parse standard window geometry strings, use
+<function>XParseGeometry</function>.
+<indexterm><primary>Window</primary><secondary>determining location</secondary></indexterm>
+<indexterm significance="preferred"><primary>XParseGeometry</primary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<funcsynopsis id='xparsegeometry'>
+<funcprototype>
+ <funcdef>int <function>XParseGeometry</function></funcdef>
+ <paramdef>char<parameter> *parsestring</parameter></paramdef>
+ <paramdef>int*x_return,<parameter> *y_return</parameter></paramdef>
+ <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>parsestring</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the string you want to parse.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the x and y offsets.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the width and height determined.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+By convention,
+X applications use a standard string to indicate window size and placement.
+<function>XParseGeometry</function>
+makes it easier to conform to this standard because it allows you
+to parse the standard window geometry.
+Specifically, this function lets you parse strings of the form:
+</para>
+<para>
+<!-- .LP -->
+<!-- .\" Start marker code here -->
+<literallayout class="monospaced">
+[=][&lt;<emphasis remap='I'>width</emphasis>&gt;{xX}&lt;<emphasis remap='I'>height</emphasis>&gt;][{+-}&lt;<emphasis remap='I'>xoffset</emphasis>&gt;{+-}&lt;<emphasis remap='I'>yoffset</emphasis>&gt;]
+</literallayout>
+<!-- .\" End marker code here -->
+</para>
+<para>
+<!-- .LP -->
+The fields map into the arguments associated with this function.
+(Items enclosed in &lt;&hairsp;&gt; are integers, items in [&hairsp;] are optional, and
+items enclosed in {&hairsp;} indicate ``choose one of.''
+Note that the brackets should not appear in the actual string.)
+If the string is not in the Host Portable Character Encoding,
+the result is implementation-dependent.
+</para>
+<para>
+<!-- .LP -->
+The
+<function>XParseGeometry</function>
+function returns a bitmask that indicates which of the four values (width,
+height, xoffset, and yoffset) were actually found in the string
+and whether the x and y values are negative.
+By convention, &minus;0 is not equal to +0, because the user needs to
+be able to say ``position the window relative to the right or bottom edge.''
+For each value found, the corresponding argument is updated.
+For each value not found, the argument is left unchanged.
+The bits are represented by
+<symbol>XValue</symbol>,
+<symbol>YValue</symbol>,
+<symbol>WidthValue</symbol>,
+<symbol>HeightValue</symbol>,
+<symbol>XNegative</symbol>,
+or
+<symbol>YNegative</symbol>
+and are defined in
+<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>.
+<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+They will be set whenever one of the values is defined
+or one of the signs is set.
+</para>
+<para>
+<!-- .LP -->
+If the function returns either the
+<symbol>XValue</symbol>
+or
+<symbol>YValue</symbol>
+flag,
+you should place the window at the requested position.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To construct a window's geometry information, use
+<function>XWMGeometry</function>.
+<indexterm significance="preferred"><primary>XWMGeometry</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xwmgeometry'>
+<funcprototype>
+ <funcdef>int <function>XWMGeometry</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> screen</parameter></paramdef>
+ <paramdef>char<parameter> *user_geom</parameter></paramdef>
+ <paramdef>char<parameter> *def_geom</parameter></paramdef>
+ <paramdef>unsignedint<parameter> bwidth</parameter></paramdef>
+ <paramdef>XSizeHints<parameter> *hints</parameter></paramdef>
+ <paramdef>int*x_return,<parameter> *y_return</parameter></paramdef>
+ <paramdef>int<parameter> *width_return</parameter></paramdef>
+ <paramdef>int<parameter> *height_return</parameter></paramdef>
+ <paramdef>int<parameter> *gravity_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the screen.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>user_geom</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the user-specified geometry or NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>def_geom</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the application's default geometry or NULL.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bwidth</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the border width.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>hints</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the size hints for the window in its normal state.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the x and y offsets.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the width and height determined.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gravity_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the window gravity.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XWMGeometry</function>
+function combines any geometry information (given in the format used by
+<function>XParseGeometry</function>)
+specified by the user and by the calling program with size hints
+(usually the ones to be stored in <property>WM_NORMAL_HINTS</property>) and returns the position,
+size, and gravity
+(<symbol>NorthWestGravity</symbol>,
+<symbol>NorthEastGravity</symbol>,
+<symbol>SouthEastGravity</symbol>,
+or
+<symbol>SouthWestGravity</symbol>)
+that describe the window.
+If the base size is not set in the
+<structname>XSizeHints</structname>
+structure,
+the minimum size is used if set.
+Otherwise, a base size of zero is assumed.
+If no minimum size is set in the hints structure,
+the base size is used.
+A mask (in the form returned by
+<function>XParseGeometry</function>)
+that describes which values came from the user specification
+and whether or not the position coordinates are relative
+to the right and bottom edges is returned.
+Note that these coordinates will have already been accounted for
+in the x_return and y_return values.
+</para>
+<para>
+<!-- .LP -->
+Note that invalid geometry specifications can cause a width or height
+of zero to be returned.
+The caller may pass the address of the hints win_gravity field
+as gravity_return to update the hints directly.
+</para>
+</sect1>
+
+<sect1 id="Manipulating_Regions">
+<title>Manipulating Regions</title>
+<!-- .XS -->
+<!-- (SN Manipulating Regions -->
+<!-- .XE -->
+<para>
+Regions are arbitrary sets of pixel locations.
+Xlib provides functions for manipulating regions.
+The opaque type
+<structname>Region</structname>
+is defined in
+<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>.
+<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+Xlib provides functions that you can use to manipulate regions.
+This section discusses how to:
+</para>
+
+<itemizedlist>
+ <listitem>
+ <para>
+Create, copy, or destroy regions
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Move or shrink regions
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Compute with regions
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Determine if regions are empty or equal
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+Locate a point or rectangle in a region
+ </para>
+ </listitem>
+</itemizedlist>
+
+<sect2 id="Creating_Copying_or_Destroying_Regions">
+<title>Creating, Copying, or Destroying Regions</title>
+<!-- .XS -->
+<!-- (SN Creating, Copying, or Destroying Regions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To create a new empty region, use
+<function>XCreateRegion</function>.
+</para>
+<para>Region XCreateRegion()</para>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To generate a region from a polygon, use
+<function>XPolygonRegion</function>.
+</para>
+<indexterm significance="preferred"><primary>XPolygonRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xpolygonregion'>
+<funcprototype>
+ <funcdef>Region <function>XPolygonRegion</function></funcdef>
+ <paramdef>XPoint<parameter> points[]</parameter></paramdef>
+ <paramdef>int<parameter> n</parameter></paramdef>
+ <paramdef>int<parameter> fill_rule</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>points</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies an array of points.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>n</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of points in the polygon.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>fill_rule</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the fill-rule you want to set for the specified GC.
+You can pass
+<symbol>EvenOddRule</symbol>
+or
+<symbol>WindingRule</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XPolygonRegion</function>
+function returns a region for the polygon defined by the points array.
+For an explanation of fill_rule,
+see
+<function>XCreateGC</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set the clip-mask of a GC to a region, use
+<function>XSetRegion</function>.
+<indexterm significance="preferred"><primary>XSetRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsetregion'>
+<funcprototype>
+ <funcdef><function>XSetRegion</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>GC<parameter> gc</parameter></paramdef>
+ <paramdef>Region<parameter> r</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>gc</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the GC.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>r</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the region.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSetRegion</function>
+function sets the clip-mask in the GC to the specified region.
+The region is specified relative to the drawable's origin.
+The resulting GC clip origin is implementation-dependent.
+Once it is set in the GC,
+the region can be destroyed.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To deallocate the storage associated with a specified region, use
+<function>XDestroyRegion</function>.
+<indexterm significance="preferred"><primary>XDestroyRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdestroyregion'>
+<funcprototype>
+ <funcdef><function>XDestroyRegion</function></funcdef>
+ <paramdef>Region<parameter> r</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>r</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the region.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+</para>
+</sect2>
+<sect2 id="Moving_or_Shrinking_Regions">
+<title>Moving or Shrinking Regions</title>
+<!-- .XS -->
+<!-- (SN Moving or Shrinking Regions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To move a region by a specified amount, use
+<function>XOffsetRegion</function>.
+<indexterm significance="preferred"><primary>XOffsetRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xoffsetregion'>
+<funcprototype>
+ <funcdef><function>XOffsetRegion</function></funcdef>
+ <paramdef>Region<parameter> r</parameter></paramdef>
+ <paramdef>intdx,<parameter> dy</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>r</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the region.
+<!-- .ds Dy move -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dx</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dy</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates,
+which define the amount you want to (Dy the specified region.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To reduce a region by a specified amount, use
+<function>XShrinkRegion</function>.
+<indexterm significance="preferred"><primary>XShrinkRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xshrinkregion'>
+<funcprototype>
+ <funcdef><function>XShrinkRegion</function></funcdef>
+ <paramdef>Region<parameter> r</parameter></paramdef>
+ <paramdef>intdx,<parameter> dy</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>r</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the region.
+<!-- .ds Dy shrink -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dx</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dy</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates,
+which define the amount you want to (Dy the specified region.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Positive values shrink the size of the region,
+and negative values expand the region.
+</para>
+</sect2>
+<sect2 id="Computing_with_Regions">
+<title>Computing with Regions</title>
+<!-- .XS -->
+<!-- (SN Computing with Regions -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To generate the smallest rectangle enclosing a region, use
+<function>XClipBox</function>.
+<indexterm significance="preferred"><primary>XClipBox</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xclipbox'>
+<funcprototype>
+ <funcdef><function>XClipBox</function></funcdef>
+ <paramdef>Region<parameter> r</parameter></paramdef>
+ <paramdef>XRectangle<parameter> *rect_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>r</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the region.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rect_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the smallest enclosing rectangle.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XClipBox</function>
+function returns the smallest rectangle enclosing the specified region.
+<!-- .sp -->
+</para>
+<para>
+<!-- .LP -->
+To compute the intersection of two regions, use
+<function>XIntersectRegion</function>.
+<indexterm significance="preferred"><primary>XIntersectRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xintersectregion'>
+<funcprototype>
+ <funcdef><function>XIntersectRegion</function></funcdef>
+ <paramdef>Regionsra,srb,<parameter> dr_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>sra</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>srb</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the two regions with which you want to perform the computation.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dr_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the result of the computation.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To compute the union of two regions, use
+<function>XUnionRegion</function>.
+<indexterm significance="preferred"><primary>XUnionRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xunionregion'>
+<funcprototype>
+ <funcdef><function>XUnionRegion</function></funcdef>
+ <paramdef>Regionsra,srb,<parameter> dr_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>sra</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>srb</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the two regions with which you want to perform the computation.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dr_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the result of the computation.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+<!-- .sp -->
+To create a union of a source region and a rectangle, use
+<function>XUnionRectWithRegion</function>.
+<indexterm significance="preferred"><primary>XUnionRectWithRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xunionrectwithregion'>
+<funcprototype>
+ <funcdef><function>XUnionRectWithRegion</function></funcdef>
+ <paramdef>XRectangle<parameter> *rectangle</parameter></paramdef>
+ <paramdef>Region<parameter> src_region</parameter></paramdef>
+ <paramdef>Region<parameter> dest_region_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rectangle</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the rectangle.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>src_region</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the source region to be used.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dest_region_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the destination region.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XUnionRectWithRegion</function>
+function updates the destination region from a union of the specified rectangle
+and the specified source region.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To subtract two regions, use
+<function>XSubtractRegion</function>.
+<indexterm significance="preferred"><primary>XSubtractRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsubtractregion'>
+<funcprototype>
+ <funcdef><function>XSubtractRegion</function></funcdef>
+ <paramdef>Regionsra,srb,<parameter> dr_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>sra</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>srb</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the two regions with which you want to perform the computation.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dr_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the result of the computation.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSubtractRegion</function>
+function subtracts srb from sra and stores the results in dr_return.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To calculate the difference between the union and intersection
+of two regions, use
+<function>XXorRegion</function>.
+<indexterm significance="preferred"><primary>XXorRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xxorregion'>
+<funcprototype>
+ <funcdef><function>XXorRegion</function></funcdef>
+ <paramdef>Regionsra,srb,<parameter> dr_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>sra</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>srb</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the two regions with which you want to perform the computation.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>dr_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the result of the computation.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+</para>
+</sect2>
+<sect2 id="Determining_if_Regions_Are_Empty_or_Equal">
+<title>Determining if Regions Are Empty or Equal</title>
+<!-- .XS -->
+<!-- (SN Determining if Regions Are Empty or Equal -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To determine if the specified region is empty, use
+<function>XEmptyRegion</function>.
+<indexterm significance="preferred"><primary>XEmptyRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xemptyregion'>
+<funcprototype>
+ <funcdef>Bool <function>XEmptyRegion</function></funcdef>
+ <paramdef>Region<parameter> r</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>r</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the region.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XEmptyRegion</function>
+function returns
+<symbol>True</symbol>
+if the region is empty.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To determine if two regions have the same offset, size, and shape, use
+<function>XEqualRegion</function>.
+<indexterm significance="preferred"><primary>XEqualRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xequalregion'>
+<funcprototype>
+ <funcdef>Bool <function>XEqualRegion</function></funcdef>
+ <paramdef>Regionr1,<parameter> r2</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>r1</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>r2</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the two regions.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XEqualRegion</function>
+function returns
+<symbol>True</symbol>
+if the two regions have the same offset, size, and shape.
+</para>
+</sect2>
+<sect2 id="Locating_a_Point_or_a_Rectangle_in_a_Region">
+<title>Locating a Point or a Rectangle in a Region</title>
+<!-- .XS -->
+<!-- (SN Locating a Point or a Rectangle in a Region -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+To determine if a specified point resides in a specified region, use
+<function>XPointInRegion</function>.
+<indexterm significance="preferred"><primary>XPointInRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xpointinregion'>
+<funcprototype>
+ <funcdef>Bool <function>XPointInRegion</function></funcdef>
+ <paramdef>Region<parameter> r</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>r</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the region.
+<!-- .ds Xy , which define the point -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XPointInRegion</function>
+function returns
+<symbol>True</symbol>
+if the point (x, y) is contained in the region r.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To determine if a specified rectangle is inside a region, use
+<function>XRectInRegion</function>.
+<indexterm significance="preferred"><primary>XRectInRegion</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrectinregion'>
+<funcprototype>
+ <funcdef>int <function>XRectInRegion</function></funcdef>
+ <paramdef>Region<parameter> r</parameter></paramdef>
+ <paramdef>intx,<parameter> y</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>r</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the region.
+<!-- .ds Xy , which define the coordinates of the upper-left corner of the rectangle -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates(Xy.
+<!-- .ds Wh , which define the rectangle -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height(Wh.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XRectInRegion</function>
+function returns
+<symbol>RectangleIn</symbol>
+if the rectangle is entirely in the specified region,
+<symbol>RectangleOut</symbol>
+if the rectangle is entirely out of the specified region,
+and
+<symbol>RectanglePart</symbol>
+if the rectangle is partially in the specified region.
+</para>
+</sect2>
+</sect1>
+<sect1 id="Using_Cut_Buffers">
+<title>Using Cut Buffers</title>
+<!-- .XS -->
+<!-- (SN Using Cut Buffers -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+<indexterm><primary>Cut Buffers</primary></indexterm>
+Xlib provides functions to manipulate cut buffers,
+a very simple form of cut-and-paste inter-client communication.
+Selections are a much more powerful and useful mechanism for
+interchanging data between clients (see section 4.5)
+and generally should be used instead of cut buffers.
+</para>
+<para>
+<!-- .LP -->
+Cut buffers are implemented as properties on the first root window
+of the display.
+The buffers can only contain text, in the STRING encoding.
+The text encoding is not changed by Xlib when fetching or storing.
+Eight buffers are provided
+and can be accessed as a ring or as explicit buffers (numbered 0 through 7).
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To store data in cut buffer 0, use
+<function>XStoreBytes</function>.
+<indexterm significance="preferred"><primary>XStoreBytes</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xstorebytes'>
+<funcprototype>
+ <funcdef><function>XStoreBytes</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *bytes</parameter></paramdef>
+ <paramdef>int<parameter> nbytes</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the bytes, which are not necessarily ASCII or null-terminated.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nbytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes to be stored.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The data can have embedded null characters
+and need not be null-terminated.
+The cut buffer's contents can be retrieved later by
+any client calling
+<function>XFetchBytes</function>.
+</para>
+<para>
+<!-- .LP -->
+<function>XStoreBytes</function>
+can generate a
+<errorname>BadAlloc</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To store data in a specified cut buffer, use
+<function>XStoreBuffer</function>.
+<indexterm significance="preferred"><primary>XStoreBuffer</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xstorebuffer'>
+<funcprototype>
+ <funcdef><function>XStoreBuffer</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *bytes</parameter></paramdef>
+ <paramdef>int<parameter> nbytes</parameter></paramdef>
+ <paramdef>int<parameter> buffer</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the bytes, which are not necessarily ASCII or null-terminated.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nbytes</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes to be stored.
+<!-- .ds Fn in which you want to store the bytes -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>buffer</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the buffer (Fn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If an invalid buffer is specified, the call has no effect.
+The data can have embedded null characters
+and need not be null-terminated.
+</para>
+<para>
+<!-- .LP -->
+<function>XStoreBuffer</function>
+can generate a
+<errorname>BadAlloc</errorname>
+error.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To return data from cut buffer 0, use
+<function>XFetchBytes</function>.
+<indexterm significance="preferred"><primary>XFetchBytes</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfetchbytes'>
+<funcprototype>
+ <funcdef>char *<function>XFetchBytes</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> *nbytes_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nbytes_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of bytes in the buffer.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFetchBytes</function>
+function
+returns the number of bytes in the nbytes_return argument,
+if the buffer contains data.
+Otherwise, the function
+returns NULL and sets nbytes to 0.
+The appropriate amount of storage is allocated and the pointer returned.
+The client must free this storage when finished with it by calling
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To return data from a specified cut buffer, use
+<function>XFetchBuffer</function>.
+<indexterm significance="preferred"><primary>XFetchBuffer</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfetchbuffer'>
+<funcprototype>
+ <funcdef>char *<function>XFetchBuffer</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> *nbytes_return</parameter></paramdef>
+ <paramdef>int<parameter> buffer</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nbytes_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of bytes in the buffer.
+<!-- .ds Fn from which you want the stored data returned -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>buffer</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the buffer (Fn.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XFetchBuffer</function>
+function returns zero to the nbytes_return argument
+if there is no data in the buffer or if an invalid
+buffer is specified.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To rotate the cut buffers, use
+<function>XRotateBuffers</function>.
+<indexterm significance="preferred"><primary>XRotateBuffers</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xrotatebuffers'>
+<funcprototype>
+ <funcdef><function>XRotateBuffers</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> rotate</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rotate</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies how much to rotate the cut buffers.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XRotateBuffers</function>
+function rotates the cut
+buffers, such that buffer 0 becomes buffer n,
+buffer 1 becomes n + 1 mod 8, and so on.
+This cut buffer numbering is global to the display.
+Note that
+<function>XRotateBuffers</function>
+generates
+<errorname>BadMatch</errorname>
+errors if any of the eight buffers have not been created.
+</para>
+</sect1>
+<sect1 id="Determining_the_Appropriate_Visual_Type">
+<title>Determining the Appropriate Visual Type</title>
+<!-- .XS -->
+<!-- (SN Determining the Appropriate Visual Type -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+A single display can support multiple screens.
+Each screen can have several different visual types supported
+at different depths.
+You can use the functions described in this section to determine
+which visual to use for your application.
+</para>
+<para>
+<!-- .LP -->
+The functions in this section use the visual information masks and the
+<structname>XVisualInfo</structname>
+structure,
+which is defined in
+<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>
+<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+and contains:
+<!-- .sM -->
+</para>
+<!-- .LP -->
+<literallayout class="monospaced">
+
+/* Visual information mask bits */
+
+
+#define VisualNoMask 0x0
+#define VisualIDMask 0x1
+#define VisualScreenMask 0x2
+#define VisualDepthMask 0x4
+#define VisualClassMask 0x8
+#define VisualRedMaskMask 0x10
+#define VisualGreenMaskMask 0x20
+#define VisualBlueMaskMask 0x40
+#define VisualColormapSizeMask 0x80
+#define VisualBitsPerRGBMask 0x100
+#define VisualAllMask 0x1FF
+
+</literallayout>
+
+<literallayout class="monospaced">
+<!-- .TA .5i 3i -->
+<!-- .ta .5i 3i -->
+/* Values */
+
+typedef struct {
+ Visual *visual;
+ VisualID visualid;
+ int screen;
+ unsigned int depth;
+ int class;
+ unsigned long red_mask;
+ unsigned long green_mask;
+ unsigned long blue_mask;
+ int colormap_size;
+ int bits_per_rgb;
+} XVisualInfo;
+</literallayout>
+
+<para>
+<!-- .LP -->
+<!-- .eM -->
+To obtain a list of visual information structures that match a specified
+template, use
+<function>XGetVisualInfo</function>.
+<indexterm significance="preferred"><primary>XGetVisualInfo</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetvisualinfo'>
+<funcprototype>
+ <funcdef>XVisualInfo *<function>XGetVisualInfo</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>long<parameter> vinfo_mask</parameter></paramdef>
+ <paramdef>XVisualInfo<parameter> *vinfo_template</parameter></paramdef>
+ <paramdef>int<parameter> *nitems_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>vinfo_mask</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the visual mask value.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>vinfo_template</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the visual attributes that are to be used in matching the visual
+structures.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>nitems_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the number of matching visual structures.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetVisualInfo</function>
+function returns a list of visual structures that have attributes
+equal to the attributes specified by vinfo_template.
+If no visual structures match the template using the specified vinfo_mask,
+<function>XGetVisualInfo</function>
+returns a NULL.
+To free the data returned by this function, use
+<function>XFree</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain the visual information that matches the specified depth and
+class of the screen, use
+<function>XMatchVisualInfo</function>.
+<indexterm significance="preferred"><primary>XMatchVisualInfo</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xmatchvisualinfo'>
+<funcprototype>
+ <funcdef>Status <function>XMatchVisualInfo</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>int<parameter> screen</parameter></paramdef>
+ <paramdef>int<parameter> depth</parameter></paramdef>
+ <paramdef>int<parameter> class</parameter></paramdef>
+ <paramdef>XVisualInfo<parameter> *vinfo_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>screen</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the screen.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>depth</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the depth of the screen.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>class</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the class of the screen.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>vinfo_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the matched visual information.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XMatchVisualInfo</function>
+function returns the visual information for a visual that matches the specified
+depth and class for a screen.
+Because multiple visuals that match the specified depth and class can exist,
+the exact visual chosen is undefined.
+If a visual is found,
+<function>XMatchVisualInfo</function>
+returns nonzero and the information on the visual to vinfo_return.
+Otherwise, when a visual is not found,
+<function>XMatchVisualInfo</function>
+returns zero.
+</para>
+</sect1>
+<sect1 id="Manipulating_Images">
+<title>Manipulating Images</title>
+<!-- .XS -->
+<!-- (SN Manipulating Images -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides several functions that perform basic operations on images.
+All operations on images are defined using an
+<structname>XImage</structname>
+structure,
+as defined in
+<filename class="headerfile">&lt;X11/Xlib.h&gt;</filename>.
+<indexterm type="file"><primary><filename class="headerfile">X11/Xlib.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xlib.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xlib.h&gt;</filename></secondary></indexterm>
+Because the number of different types of image formats can be very large,
+this hides details of image storage properly from applications.
+</para>
+<para>
+<!-- .LP -->
+This section describes the functions for generic operations on images.
+Manufacturers can provide very fast implementations of these for the
+formats frequently encountered on their hardware.
+These functions are neither sufficient nor desirable to use for general image
+processing.
+Rather, they are here to provide minimal functions on screen format
+images.
+The basic operations for getting and putting images are
+<function>XGetImage</function>
+and
+<function>XPutImage</function>.
+</para>
+<para>
+<!-- .LP -->
+Note that no functions have been defined, as yet, to read and write images
+to and from disk files.
+</para>
+<para>
+<!-- .LP -->
+The
+<structname>XImage</structname>
+structure describes an image as it exists in the client's memory.
+The user can request that some of the members such as height, width,
+and xoffset be changed when the image is sent to the server.
+Note that bytes_per_line in concert with offset can be used to
+extract a subset of the image.
+Other members (for example, byte order, bitmap_unit, and so forth)
+are characteristics of both the image and the server.
+If these members
+differ between the image and the server,
+<function>XPutImage</function>
+makes the appropriate conversions.
+The first byte of the first line of
+plane n must be located at the address (data + (n * height * bytes_per_line)).
+For a description of the
+<structname>XImage</structname>
+structure,
+see section 8.7.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To allocate an
+<structname>XImage</structname>
+structure and initialize it with image format values from a display, use
+<function>XCreateImage</function>.
+<indexterm significance="preferred"><primary>XCreateImage</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreateimage'>
+<funcprototype>
+ <funcdef>XImage *<function>XCreateImage</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Visual<parameter> *visual</parameter></paramdef>
+ <paramdef>unsignedint<parameter> depth</parameter></paramdef>
+ <paramdef>int<parameter> format</parameter></paramdef>
+ <paramdef>int<parameter> offset</parameter></paramdef>
+ <paramdef>char<parameter> *data</parameter></paramdef>
+ <paramdef>unsignedint<parameter> width</parameter></paramdef>
+ <paramdef>unsignedint<parameter> height</parameter></paramdef>
+ <paramdef>int<parameter> bitmap_pad</parameter></paramdef>
+ <paramdef>int<parameter> bytes_per_line</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>visual</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the
+<structname>Visual</structname>
+structure.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>depth</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the depth of the image.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>format</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the format for the image.
+You can pass
+<symbol>XYBitmap</symbol>,
+<symbol>XYPixmap</symbol>,
+or
+<symbol>ZPixmap</symbol>.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>offset</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of pixels to ignore at the beginning of the scanline.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the image data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the width of the image, in pixels.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the height of the image, in pixels.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bitmap_pad</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the quantum of a scanline (8, 16, or 32).
+In other words, the start of one scanline is separated in client memory from
+the start of the next scanline by an integer multiple of this many bits.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bytes_per_line</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the number of bytes in the client image between
+the start of one scanline and the start of the next.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreateImage</function>
+function allocates the memory needed for an
+<structname>XImage</structname>
+structure for the
+specified display but does not allocate space for the image itself.
+Rather, it initializes the structure byte-order, bit-order, and bitmap-unit
+values from the display and returns a pointer to the
+<structname>XImage</structname>
+structure.
+The red, green, and blue mask values are defined for Z format images only
+and are derived from the
+<structname>Visual</structname>
+structure passed in.
+Other values also are passed in.
+The offset permits the rapid displaying of the image without requiring each
+scanline to be shifted into position.
+If you pass a zero value in bytes_per_line,
+Xlib assumes that the scanlines are contiguous
+in memory and calculates the value of bytes_per_line itself.
+</para>
+<para>
+<!-- .LP -->
+Note that when the image is created using
+<function>XCreateImage</function>,
+<function>XGetImage</function>,
+or
+<function>XSubImage</function>,
+the destroy procedure that the
+<function>XDestroyImage</function>
+function calls frees both the image structure
+and the data pointed to by the image structure.
+</para>
+<para>
+<!-- .LP -->
+The basic functions used to get a pixel, set a pixel, create a subimage,
+and add a constant value to an image are defined in the image object.
+The functions in this section are really macro invocations of the functions
+in the image object and are defined in
+<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>.
+<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To obtain a pixel value in an image, use
+<function>XGetPixel</function>.
+<indexterm significance="preferred"><primary>XGetPixel</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xgetpixel'>
+<funcprototype>
+ <funcdef>unsigned long <function>XGetPixel</function></funcdef>
+ <paramdef>XImage<parameter> *ximage</parameter></paramdef>
+ <paramdef>int<parameter> x</parameter></paramdef>
+ <paramdef>int<parameter> y</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ximage</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the image.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XGetPixel</function>
+function returns the specified pixel from the named image.
+The pixel value is returned in normalized format (that is,
+the least significant byte of the long is the least significant byte
+of the pixel).
+The image must contain the x and y coordinates.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To set a pixel value in an image, use
+<function>XPutPixel</function>.
+<indexterm significance="preferred"><primary>XPutPixel</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xputpixel'>
+<funcprototype>
+ <funcdef><function>XPutPixel</function></funcdef>
+ <paramdef>XImage<parameter> *ximage</parameter></paramdef>
+ <paramdef>int<parameter> x</parameter></paramdef>
+ <paramdef>int<parameter> y</parameter></paramdef>
+ <paramdef>unsignedlong<parameter> pixel</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ximage</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the image.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>pixel</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the new pixel value.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XPutPixel</function>
+function overwrites the pixel in the named image with the specified pixel value.
+The input pixel value must be in normalized format
+(that is, the least significant byte of the long is the least significant
+byte of the pixel).
+The image must contain the x and y coordinates.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create a subimage, use
+<function>XSubImage</function>.
+<indexterm significance="preferred"><primary>XSubImage</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsubimage'>
+<funcprototype>
+ <funcdef>XImage *<function>XSubImage</function></funcdef>
+ <paramdef>XImage<parameter> *ximage</parameter></paramdef>
+ <paramdef>int<parameter> x</parameter></paramdef>
+ <paramdef>int<parameter> y</parameter></paramdef>
+ <paramdef>unsignedint<parameter> subimage_width</parameter></paramdef>
+ <paramdef>unsignedint<parameter> subimage_height</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ximage</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the image.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the x and y coordinates.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>subimage_width</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the width of the new subimage, in pixels.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>subimage_height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the height of the new subimage, in pixels.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XSubImage</function>
+function creates a new image that is a subsection of an existing one.
+It allocates the memory necessary for the new
+<structname>XImage</structname>
+structure
+and returns a pointer to the new image.
+The data is copied from the source image,
+and the image must contain the rectangle defined by x, y, subimage_width,
+and subimage_height.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To increment each pixel in an image by a constant value, use
+<function>XAddPixel</function>.
+<indexterm significance="preferred"><primary>XAddPixel</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xaddpixel'>
+<funcprototype>
+ <funcdef><function>XAddPixel</function></funcdef>
+ <paramdef>XImage<parameter> *ximage</parameter></paramdef>
+ <paramdef>long<parameter> value</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ximage</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the image.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>value</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the constant value that is to be added.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XAddPixel</function>
+function adds a constant value to every pixel in an image.
+It is useful when you have a base pixel value from allocating
+color resources and need to manipulate the image to that form.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To deallocate the memory allocated in a previous call to
+<function>XCreateImage</function>,
+use
+<function>XDestroyImage</function>.
+<indexterm significance="preferred"><primary>XDestroyImage</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdestroyimage'>
+<funcprototype>
+ <funcdef><function>XDestroyImage</function></funcdef>
+ <paramdef>XImage *<parameter>ximage</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>ximage</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the image.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDestroyImage</function>
+function deallocates the memory associated with the
+<structname>XImage</structname>
+structure.
+</para>
+<para>
+<!-- .LP -->
+Note that when the image is created using
+<function>XCreateImage</function>,
+<function>XGetImage</function>,
+or
+<function>XSubImage</function>,
+the destroy procedure that this macro calls
+frees both the image structure and the data pointed to by the image structure.
+</para>
+</sect1>
+<sect1 id="Manipulating_Bitmaps">
+<title>Manipulating Bitmaps</title>
+<!-- .XS -->
+<!-- (SN Manipulating Bitmaps -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+Xlib provides functions that you can use to read a bitmap from a file,
+save a bitmap to a file, or create a bitmap.
+This section describes those functions that transfer bitmaps to and
+from the client's file system, thus allowing their reuse in a later
+connection (for example, from an entirely different client or to a
+different display or server).
+</para>
+<para>
+<!-- .LP -->
+The X version 11 bitmap file format is:
+</para>
+<para>
+<!-- .LP -->
+<!-- .sM -->
+<literallayout class="monospaced">
+#define <emphasis remap='I'>name</emphasis>_width <emphasis remap='I'>width</emphasis>
+#define <emphasis remap='I'>name</emphasis>_height <emphasis remap='I'>height</emphasis>
+#define <emphasis remap='I'>name</emphasis>_x_hot <emphasis remap='I'>x</emphasis>
+#define <emphasis remap='I'>name</emphasis>_y_hot <emphasis remap='I'>y</emphasis>
+static unsigned char <emphasis remap='I'>name</emphasis>_bits[] = { 0x<emphasis remap='I'>NN</emphasis>,... }
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The lines for the variables ending with _x_hot and _y_hot suffixes are optional
+because they are present only if a hotspot has been defined for this bitmap.
+The lines for the other variables are required.
+The word ``unsigned'' is optional;
+that is, the type of the _bits array can be ``char'' or ``unsigned char''.
+The _bits array must be large enough to contain the size bitmap.
+The bitmap unit is 8.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To read a bitmap from a file and store it in a pixmap, use
+<function>XReadBitmapFile</function>.
+<indexterm significance="preferred"><primary>XReadBitmapFile</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xreadbitmapfile'>
+<funcprototype>
+ <funcdef>int <function>XReadBitmapFile</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>char<parameter> *filename</parameter></paramdef>
+ <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
+ <paramdef>Pixmap<parameter> *bitmap_return</parameter></paramdef>
+ <paramdef>int*x_hot_return,<parameter> *y_hot_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Dr \ that indicates the screen -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable(Dr.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>filename</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the file name to use.
+The format of the file name is operating-system dependent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the width and height values of the read in bitmap file.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bitmap_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the bitmap that is created.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x_hot_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y_hot_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the hotspot coordinates.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XReadBitmapFile</function>
+function reads in a file containing a bitmap.
+The file is parsed in the encoding of the current locale.
+The ability to read other than the standard format
+is implementation-dependent.
+If the file cannot be opened,
+<function>XReadBitmapFile</function>
+returns
+<returnvalue>BitmapOpenFailed</returnvalue>.
+If the file can be opened but does not contain valid bitmap data,
+it returns
+<returnvalue>BitmapFileInvalid</returnvalue>.
+If insufficient working storage is allocated,
+it returns
+<returnvalue>BitmapNoMemory</returnvalue>.
+If the file is readable and valid,
+it returns
+<returnvalue>BitmapSuccess</returnvalue>.
+</para>
+<para>
+<!-- .LP -->
+<function>XReadBitmapFile</function>
+returns the bitmap's height and width, as read
+from the file, to width_return and height_return.
+It then creates a pixmap of the appropriate size,
+reads the bitmap data from the file into the pixmap,
+and assigns the pixmap to the caller's variable bitmap.
+The caller must free the bitmap using
+<function>XFreePixmap</function>
+when finished.
+If <emphasis remap='I'>name</emphasis>_x_hot and <emphasis remap='I'>name</emphasis>_y_hot exist,
+<function>XReadBitmapFile</function>
+returns them to x_hot_return and y_hot_return;
+otherwise, it returns &minus;1,&minus;1.
+</para>
+<para>
+<!-- .LP -->
+<function>XReadBitmapFile</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadDrawable</errorname>,
+and
+<errorname>BadGC</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To read a bitmap from a file and return it as data, use
+<function>XReadBitmapFileData</function>.
+<indexterm significance="preferred"><primary>XReadBitmapFileData</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xreadbitmapfiledata'>
+<funcprototype>
+ <funcdef>int <function>XReadBitmapFileData</function></funcdef>
+ <paramdef>char<parameter> *filename</parameter></paramdef>
+ <paramdef>unsignedint*width_return,<parameter> *height_return</parameter></paramdef>
+ <paramdef>unsignedchar<parameter> *data_return</parameter></paramdef>
+ <paramdef>int*x_hot_return,<parameter> *y_hot_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>filename</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the file name to use.
+The format of the file name is operating-system dependent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the width and height values of the read in bitmap file.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the bitmap data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x_hot_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y_hot_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Return the hotspot coordinates.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XReadBitmapFileData</function>
+function reads in a file containing a bitmap, in the same manner as
+<function>XReadBitmapFile</function>,
+but returns the data directly rather than creating a pixmap in the server.
+The bitmap data is returned in data_return; the client must free this
+storage when finished with it by calling
+<function>XFree</function>.
+The status and other return values are the same as for
+<function>XReadBitmapFile</function>.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To write out a bitmap from a pixmap to a file, use
+<function>XWriteBitmapFile</function>.
+<indexterm significance="preferred"><primary>XWriteBitmapFile</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xwritebitmapfile'>
+<funcprototype>
+ <funcdef>int <function>XWriteBitmapFile</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>char<parameter> *filename</parameter></paramdef>
+ <paramdef>Pixmap<parameter> bitmap</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>intx_hot,<parameter> y_hot</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>filename</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the file name to use.
+The format of the file name is operating-system dependent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bitmap</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the bitmap.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>x_hot</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>y_hot</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify where to place the hotspot coordinates (or &minus;1,&minus;1 if none are present)
+in the file.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XWriteBitmapFile</function>
+function writes a bitmap out to a file in the X Version 11 format.
+The name used in the output file is derived from the file name
+by deleting the directory prefix.
+The file is written in the encoding of the current locale.
+If the file cannot be opened for writing,
+it returns
+<returnvalue>BitmapOpenFailed</returnvalue>.
+If insufficient memory is allocated,
+<function>XWriteBitmapFile</function>
+returns
+<returnvalue>BitmapNoMemory</returnvalue>;
+otherwise, on no error,
+it returns
+<returnvalue>BitmapSuccess</returnvalue>.
+If x_hot and y_hot are not &minus;1, &minus;1,
+<function>XWriteBitmapFile</function>
+writes them out as the hotspot coordinates for the bitmap.
+</para>
+<para>
+<!-- .LP -->
+<function>XWriteBitmapFile</function>
+can generate
+<errorname>BadDrawable</errorname>
+and
+<errorname>BadMatch</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create a pixmap and then store bitmap-format data into it, use
+<function>XCreatePixmapFromBitmapData</function>.
+<indexterm significance="preferred"><primary>XCreatePixmapFromBitmapData</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreatepixmapfrombitmapdata'>
+<funcprototype>
+ <funcdef>Pixmap <function>XCreatePixmapFromBitmapData</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>char<parameter> *data</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+ <paramdef>unsignedlongfg,<parameter> bg</parameter></paramdef>
+ <paramdef>unsignedint<parameter> depth</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Dr \ that indicates the screen -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable(Dr.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the data in bitmap format.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>fg</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>bg</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the foreground and background pixel values to use.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>depth</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the depth of the pixmap.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreatePixmapFromBitmapData</function>
+function creates a pixmap of the given depth and then does a bitmap-format
+<function>XPutImage</function>
+of the data into it.
+The depth must be supported by the screen of the specified drawable,
+or a
+<errorname>BadMatch</errorname>
+error results.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreatePixmapFromBitmapData</function>
+can generate
+<errorname>BadAlloc</errorname>,
+<errorname>BadDrawable</errorname>,
+<errorname>BadGC</errorname>,
+and
+<errorname>BadValue</errorname>
+errors.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To include a bitmap written out by
+<function>XWriteBitmapFile</function>
+<indexterm><primary>XWriteBitmapFile</primary></indexterm>
+in a program directly, as opposed to reading it in every time at run time, use
+<function>XCreateBitmapFromData</function>.
+<indexterm significance="preferred"><primary>XCreateBitmapFromData</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xcreatebitmapfromdata'>
+<funcprototype>
+ <funcdef>Pixmap <function>XCreateBitmapFromData</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>Drawable<parameter> d</parameter></paramdef>
+ <paramdef>char<parameter> *data</parameter></paramdef>
+ <paramdef>unsignedintwidth,<parameter> height</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+<!-- .ds Dr \ that indicates the screen -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>d</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the drawable(Dr.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the location of the bitmap data.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>width</emphasis>
+ </term>
+ <listitem>
+ <para>
+<!-- .br -->
+<!-- .ns -->
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>height</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specify the width and height.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XCreateBitmapFromData</function>
+function allows you to include in your C program (using
+<code>#include</code>)
+a bitmap file that was written out by
+<function>XWriteBitmapFile</function>
+(X version 11 format only) without reading in the bitmap file.
+The following example creates a gray bitmap:
+</para>
+<para>
+<!-- .LP -->
+<literallayout class="monospaced">
+#include "gray.bitmap"
+<!-- .sp 6p -->
+Pixmap bitmap;
+bitmap = XCreateBitmapFromData(display, window, gray_bits, gray_width, gray_height);
+</literallayout>
+</para>
+<para>
+<!-- .LP -->
+If insufficient working storage was allocated,
+<function>XCreateBitmapFromData</function>
+returns
+<symbol>None</symbol>.
+It is your responsibility to free the
+bitmap using
+<function>XFreePixmap</function>
+when finished.
+</para>
+<para>
+<!-- .LP -->
+<function>XCreateBitmapFromData</function>
+can generate
+<errorname>BadAlloc</errorname>
+and
+<errorname>BadGC</errorname>
+errors.
+</para>
+</sect1>
+<sect1 id="Using_the_Context_Manager">
+<title>Using the Context Manager</title>
+<!-- .XS -->
+<!-- (SN Using the Context Manager -->
+<!-- .XE -->
+<para>
+<!-- .LP -->
+The context manager provides a way of associating data with an X resource ID
+(mostly typically a window) in your program.
+Note that this is local to your program;
+the data is not stored in the server on a property list.
+Any amount of data in any number of pieces can be associated with a
+resource ID,
+and each piece of data has a type associated with it.
+The context manager requires knowledge of the resource ID
+and type to store or retrieve data.
+</para>
+<para>
+<!-- .LP -->
+Essentially, the context manager can be viewed as a two-dimensional,
+sparse array: one dimension is subscripted by the X resource ID
+and the other by a context type field.
+Each entry in the array contains a pointer to the data.
+Xlib provides context management functions with which you can
+save data values, get data values, delete entries, and create a unique
+context type.
+The symbols used are in
+<filename class="headerfile">&lt;X11/Xutil.h&gt;</filename>.
+<indexterm type="file"><primary><filename class="headerfile">X11/Xutil.h</filename></primary></indexterm>
+<indexterm><primary>Files</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+<indexterm><primary>Headers</primary><secondary><filename class="headerfile">&lt;X11/Xutil.h&gt;</filename></secondary></indexterm>
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To save a data value that corresponds to a resource ID and context type, use
+<function>XSaveContext</function>.
+<indexterm significance="preferred"><primary>XSaveContext</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xsavecontext'>
+<funcprototype>
+ <funcdef>int <function>XSaveContext</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XID<parameter> rid</parameter></paramdef>
+ <paramdef>XContext<parameter> context</parameter></paramdef>
+ <paramdef>XPointer<parameter> data</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rid</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource ID with which the data is associated.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>context</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the context type to which the data belongs.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the data to be associated with the window and type.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+If an entry with the specified resource ID and type already exists,
+<function>XSaveContext</function>
+overrides it with the specified context.
+The
+<function>XSaveContext</function>
+function returns a nonzero error code if an error has occurred
+and zero otherwise.
+Possible errors are
+<symbol>XCNOMEM</symbol>
+(out of memory).
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To get the data associated with a resource ID and type, use
+<function>XFindContext</function>.
+<indexterm significance="preferred"><primary>XFindContext</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xfindcontext'>
+<funcprototype>
+ <funcdef>int <function>XFindContext</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XID<parameter> rid</parameter></paramdef>
+ <paramdef>XContext<parameter> context</parameter></paramdef>
+ <paramdef>XPointer<parameter> *data_return</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rid</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource ID with which the data is associated.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>context</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the context type to which the data belongs.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>data_return</emphasis>
+ </term>
+ <listitem>
+ <para>
+Returns the data.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+Because it is a return value,
+the data is a pointer.
+The
+<function>XFindContext</function>
+function returns a nonzero error code if an error has occurred
+and zero otherwise.
+Possible errors are
+<symbol>XCNOENT</symbol>
+(context-not-found).
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To delete an entry for a given resource ID and type, use
+<function>XDeleteContext</function>.
+<indexterm significance="preferred"><primary>XDeleteContext</primary></indexterm>
+<!-- .sM -->
+<funcsynopsis id='xdeletecontext'>
+<funcprototype>
+ <funcdef>int <function>XDeleteContext</function></funcdef>
+ <paramdef>Display<parameter> *display</parameter></paramdef>
+ <paramdef>XID<parameter> rid</parameter></paramdef>
+ <paramdef>XContext<parameter> context</parameter></paramdef>
+</funcprototype>
+</funcsynopsis>
+<!-- .FN -->
+<variablelist>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>display</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the connection to the X server.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>rid</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the resource ID with which the data is associated.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>
+ <emphasis remap='I'>context</emphasis>
+ </term>
+ <listitem>
+ <para>
+Specifies the context type to which the data belongs.
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</para>
+<para>
+<!-- .LP -->
+<!-- .eM -->
+The
+<function>XDeleteContext</function>
+function deletes the entry for the given resource ID
+and type from the data structure.
+This function returns the same error codes that
+<function>XFindContext</function>
+returns if called with the same arguments.
+<function>XDeleteContext</function>
+does not free the data whose address was saved.
+</para>
+<para>
+<!-- .LP -->
+<!-- .sp -->
+To create a unique context type that may be used in subsequent calls to
+<function>XSaveContext</function>
+and
+<function>XFindContext</function>,
+use
+<function>XUniqueContext</function>.
+</para>
+<para>XContext XuniqueContext()</para>
+
+</sect1>
+</chapter>
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-30 13:59:23 +0000