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-<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V3.1//EN" [
-<!ENTITY version SYSTEM "version.sgml">
-<!ENTITY confdir SYSTEM "confdir.sgml">
-]>
-<!--
- Copyright © 2003 Keith Packard
-
- Permission to use, copy, modify, distribute, and sell this software and its
- documentation for any purpose is hereby granted without fee, provided that
- the above copyright notice appear in all copies and that both that
- copyright notice and this permission notice appear in supporting
- documentation, and that the name of Keith Packard not be used in
- advertising or publicity pertaining to distribution of the software without
- specific, written prior permission. Keith Packard makes no
- representations about the suitability of this software for any purpose. It
- is provided "as is" without express or implied warranty.
-
- THE AUTHOR(S) DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
- INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
- EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY SPECIAL, INDIRECT OR
- CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
- DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
- TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
- PERFORMANCE OF THIS SOFTWARE.
--->
-<refentry>
-<refmeta>
- <refentrytitle>fonts-conf</refentrytitle>
- <manvolnum>5</manvolnum>
-</refmeta>
-<refnamediv>
- <refname>fonts.conf</refname>
- <refpurpose>Font configuration files</refpurpose>
-</refnamediv>
-<refsynopsisdiv>
-<synopsis>
- &confdir;/fonts.conf
- &confdir;/fonts.dtd
- &confdir;/conf.d
- ~/.fonts.conf.d
- ~/.fonts.conf
-</synopsis>
-</refsynopsisdiv>
-<refsect1><title>Description</title>
- <para>
-Fontconfig is a library designed to provide system-wide font configuration,
-customization and application access.
- </para>
-</refsect1>
-<refsect1><title>Functional Overview</title>
- <para>
-Fontconfig contains two essential modules, the configuration module which
-builds an internal configuration from XML files and the matching module
-which accepts font patterns and returns the nearest matching font.
- </para>
- <refsect2><title>Font Configuration</title>
- <para>
-The configuration module consists of the FcConfig datatype, libexpat and
-FcConfigParse which walks over an XML tree and amends a configuration with
-data found within. From an external perspective, configuration of the
-library consists of generating a valid XML tree and feeding that to
-FcConfigParse. The only other mechanism provided to applications for
-changing the running configuration is to add fonts and directories to the
-list of application-provided font files.
- </para><para>
-The intent is to make font configurations relatively static, and shared by
-as many applications as possible. It is hoped that this will lead to more
-stable font selection when passing names from one application to another.
-XML was chosen as a configuration file format because it provides a format
-which is easy for external agents to edit while retaining the correct
-structure and syntax.
- </para><para>
-Font configuration is separate from font matching; applications needing to
-do their own matching can access the available fonts from the library and
-perform private matching. The intent is to permit applications to pick and
-choose appropriate functionality from the library instead of forcing them to
-choose between this library and a private configuration mechanism. The hope
-is that this will ensure that configuration of fonts for all applications
-can be centralized in one place. Centralizing font configuration will
-simplify and regularize font installation and customization.
- </para>
- </refsect2>
- <refsect2>
- <title>Font Properties</title>
- <para>
-While font patterns may contain essentially any properties, there are some
-well known properties with associated types. Fontconfig uses some of these
-properties for font matching and font completion. Others are provided as a
-convenience for the applications' rendering mechanism.
- </para>
- <programlisting>
- Property Type Description
- --------------------------------------------------------------
- family String Font family names
- familylang String Languages corresponding to each family
- style String Font style. Overrides weight and slant
- stylelang String Languages corresponding to each style
- fullname String Font full names (often includes style)
- fullnamelang String Languages corresponding to each fullname
- slant Int Italic, oblique or roman
- weight Int Light, medium, demibold, bold or black
- size Double Point size
- width Int Condensed, normal or expanded
- aspect Double Stretches glyphs horizontally before hinting
- pixelsize Double Pixel size
- spacing Int Proportional, dual-width, monospace or charcell
- foundry String Font foundry name
- antialias Bool Whether glyphs can be antialiased
- hinting Bool Whether the rasterizer should use hinting
- hintstyle Int Automatic hinting style
- verticallayout Bool Use vertical layout
- autohint Bool Use autohinter instead of normal hinter
- globaladvance Bool Use font global advance data
- file String The filename holding the font
- index Int The index of the font within the file
- ftface FT_Face Use the specified FreeType face object
- rasterizer String Which rasterizer is in use
- outline Bool Whether the glyphs are outlines
- scalable Bool Whether glyphs can be scaled
- scale Double Scale factor for point->pixel conversions
- dpi Double Target dots per inch
- rgba Int unknown, rgb, bgr, vrgb, vbgr,
- none - subpixel geometry
- lcdfilter Int Type of LCD filter
- minspace Bool Eliminate leading from line spacing
- charset CharSet Unicode chars encoded by the font
- lang String List of RFC-3066-style languages this
- font supports
- fontversion Int Version number of the font
- capability String List of layout capabilities in the font
- embolden Bool Rasterizer should synthetically embolden the font
- </programlisting>
- </refsect2>
- <refsect2>
- <title>Font Matching</title>
- <para>
-Fontconfig performs matching by measuring the distance from a provided
-pattern to all of the available fonts in the system. The closest matching
-font is selected. This ensures that a font will always be returned, but
-doesn't ensure that it is anything like the requested pattern.
- </para><para>
-Font matching starts with an application constructed pattern. The desired
-attributes of the resulting font are collected together in a pattern. Each
-property of the pattern can contain one or more values; these are listed in
-priority order; matches earlier in the list are considered "closer" than
-matches later in the list.
- </para><para>
-The initial pattern is modified by applying the list of editing instructions
-specific to patterns found in the configuration; each consists of a match
-predicate and a set of editing operations. They are executed in the order
-they appeared in the configuration. Each match causes the associated
-sequence of editing operations to be applied.
- </para><para>
-After the pattern has been edited, a sequence of default substitutions are
-performed to canonicalize the set of available properties; this avoids the
-need for the lower layers to constantly provide default values for various
-font properties during rendering.
- </para><para>
-The canonical font pattern is finally matched against all available fonts.
-The distance from the pattern to the font is measured for each of several
-properties: foundry, charset, family, lang, spacing, pixelsize, style,
-slant, weight, antialias, rasterizer and outline. This list is in priority
-order -- results of comparing earlier elements of this list weigh more
-heavily than later elements.
- </para><para>
-There is one special case to this rule; family names are split into two
-bindings; strong and weak. Strong family names are given greater precedence
-in the match than lang elements while weak family names are given lower
-precedence than lang elements. This permits the document language to drive
-font selection when any document specified font is unavailable.
- </para><para>
-The pattern representing that font is augmented to include any properties
-found in the pattern but not found in the font itself; this permits the
-application to pass rendering instructions or any other data through the
-matching system. Finally, the list of editing instructions specific to
-fonts found in the configuration are applied to the pattern. This modified
-pattern is returned to the application.
- </para><para>
-The return value contains sufficient information to locate and rasterize the
-font, including the file name, pixel size and other rendering data. As
-none of the information involved pertains to the FreeType library,
-applications are free to use any rasterization engine or even to take
-the identified font file and access it directly.
- </para><para>
-The match/edit sequences in the configuration are performed in two passes
-because there are essentially two different operations necessary -- the
-first is to modify how fonts are selected; aliasing families and adding
-suitable defaults. The second is to modify how the selected fonts are
-rasterized. Those must apply to the selected font, not the original pattern
-as false matches will often occur.
- </para>
- </refsect2>
- <refsect2><title>Font Names</title>
- <para>
-Fontconfig provides a textual representation for patterns that the library
-can both accept and generate. The representation is in three parts, first a
-list of family names, second a list of point sizes and finally a list of
-additional properties:
- </para>
- <programlisting>
- &lt;families&gt;-&lt;point sizes&gt;:&lt;name1&gt;=&lt;values1&gt;:&lt;name2&gt;=&lt;values2&gt;...
- </programlisting>
- <para>
-Values in a list are separated with commas. The name needn't include either
-families or point sizes; they can be elided. In addition, there are
-symbolic constants that simultaneously indicate both a name and a value.
-Here are some examples:
- </para>
- <programlisting>
- Name Meaning
- ----------------------------------------------------------
- Times-12 12 point Times Roman
- Times-12:bold 12 point Times Bold
- Courier:italic Courier Italic in the default size
- Monospace:matrix=1 .1 0 1 The users preferred monospace font
- with artificial obliquing
- </programlisting>
- <para>
-The '\', '-', ':' and ',' characters in family names must be preceeded by a
-'\' character to avoid having them misinterpreted. Similarly, values
-containing '\', '=', '_', ':' and ',' must also have them preceeded by a
-'\' character. The '\' characters are stripped out of the family name and
-values as the font name is read.
- </para>
- </refsect2>
-</refsect1>
-<refsect1><title>Debugging Applications</title>
- <para>
-To help diagnose font and applications problems, fontconfig is built with a
-large amount of internal debugging left enabled. It is controlled by means
-of the FC_DEBUG environment variable. The value of this variable is
-interpreted as a number, and each bit within that value controls different
-debugging messages.
- </para>
- <programlisting>
- Name Value Meaning
- ---------------------------------------------------------
- MATCH 1 Brief information about font matching
- MATCHV 2 Extensive font matching information
- EDIT 4 Monitor match/test/edit execution
- FONTSET 8 Track loading of font information at startup
- CACHE 16 Watch cache files being written
- CACHEV 32 Extensive cache file writing information
- PARSE 64 (no longer in use)
- SCAN 128 Watch font files being scanned to build caches
- SCANV 256 Verbose font file scanning information
- MEMORY 512 Monitor fontconfig memory usage
- CONFIG 1024 Monitor which config files are loaded
- LANGSET 2048 Dump char sets used to construct lang values
- OBJTYPES 4096 Display message when value typechecks fail
- </programlisting>
- <para>
-Add the value of the desired debug levels together and assign that (in
-base 10) to the FC_DEBUG environment variable before running the
-application. Output from these statements is sent to stdout.
- </para>
-</refsect1>
-<refsect1><title>Lang Tags</title>
- <para>
-Each font in the database contains a list of languages it supports. This is
-computed by comparing the Unicode coverage of the font with the orthography
-of each language. Languages are tagged using an RFC-3066 compatible naming
-and occur in two parts -- the ISO 639 language tag followed a hyphen and then
-by the ISO 3166 country code. The hyphen and country code may be elided.
- </para><para>
-Fontconfig has orthographies for several languages built into the library.
-No provision has been made for adding new ones aside from rebuilding the
-library. It currently supports 122 of the 139 languages named in ISO 639-1,
-141 of the languages with two-letter codes from ISO 639-2 and another 30
-languages with only three-letter codes. Languages with both two and three
-letter codes are provided with only the two letter code.
- </para><para>
-For languages used in multiple territories with radically different
-character sets, fontconfig includes per-territory orthographies. This
-includes Azerbaijani, Kurdish, Pashto, Tigrinya and Chinese.
- </para>
-</refsect1>
-<refsect1><title>Configuration File Format</title>
- <para>
-Configuration files for fontconfig are stored in XML format; this
-format makes external configuration tools easier to write and ensures that
-they will generate syntactically correct configuration files. As XML
-files are plain text, they can also be manipulated by the expert user using
-a text editor.
- </para><para>
-The fontconfig document type definition resides in the external entity
-"fonts.dtd"; this is normally stored in the default font configuration
-directory (&confdir;). Each configuration file should contain the
-following structure:
- <programlisting>
- &lt;?xml version="1.0"?&gt;
- &lt;!DOCTYPE fontconfig SYSTEM "fonts.dtd"&gt;
- &lt;fontconfig&gt;
- ...
- &lt;/fontconfig&gt;
- </programlisting>
- </para>
-<refsect2><title><literal>&lt;fontconfig&gt;</literal></title><para>
-This is the top level element for a font configuration and can contain
-<literal>&lt;dir&gt;</literal>, <literal>&lt;cache&gt;</literal>, <literal>&lt;include&gt;</literal>, <literal>&lt;match&gt;</literal> and <literal>&lt;alias&gt;</literal> elements in any order.
- </para></refsect2>
- <refsect2><title><literal>&lt;dir&gt;</literal></title><para>
-This element contains a directory name which will be scanned for font files
-to include in the set of available fonts.
- </para></refsect2>
- <refsect2><title><literal>&lt;cache&gt;</literal></title><para>
-This element contains a file name for the per-user cache of font
-information. If it starts with '~', it refers to a file in the users
-home directory. This file is used to hold information about fonts that
-isn't present in the per-directory cache files. It is automatically
-maintained by the fontconfig library. The default for this file
-is ``~/.fonts.cache-<literal>&lt;version&gt;</literal>'', where <literal>&lt;version&gt;</literal> is the font configuration
-file version number (currently 2).
- </para></refsect2>
- <refsect2><title><literal>&lt;include ignore_missing="no"&gt;</literal></title><para>
-This element contains the name of an additional configuration file or
-directory. If a directory, every file within that directory starting with an
-ASCII digit (U+0030 - U+0039) and ending with the string ``.conf'' will be processed in sorted order. When
-the XML datatype is traversed by FcConfigParse, the contents of the file(s)
-will also be incorporated into the configuration by passing the filename(s) to
-FcConfigLoadAndParse. If 'ignore_missing' is set to "yes" instead of the
-default "no", a missing file or directory will elicit no warning message from
-the library.
- </para></refsect2>
- <refsect2><title><literal>&lt;config&gt;</literal></title><para>
-This element provides a place to consolidate additional configuration
-information. <literal>&lt;config&gt;</literal> can contain <literal>&lt;blank&gt;</literal> and <literal>&lt;rescan&gt;</literal> elements in any
-order.
- </para></refsect2>
- <refsect2><title><literal>&lt;blank&gt;</literal></title><para>
-Fonts often include "broken" glyphs which appear in the encoding but are
-drawn as blanks on the screen. Within the <literal>&lt;blank&gt;</literal> element, place each
-Unicode characters which is supposed to be blank in an <literal>&lt;int&gt;</literal> element.
-Characters outside of this set which are drawn as blank will be elided from
-the set of characters supported by the font.
- </para></refsect2>
- <refsect2><title><literal>&lt;rescan&gt;</literal></title><para>
-The <literal>&lt;rescan&gt;</literal> element holds an <literal>&lt;int&gt;</literal> element which indicates the default
-interval between automatic checks for font configuration changes.
-Fontconfig will validate all of the configuration files and directories and
-automatically rebuild the internal datastructures when this interval passes.
- </para></refsect2>
- <refsect2><title><literal>&lt;selectfont&gt;</literal></title><para>
-This element is used to black/white list fonts from being listed or matched
-against. It holds acceptfont and rejectfont elements.
- </para></refsect2>
- <refsect2><title><literal>&lt;acceptfont&gt;</literal></title><para>
-Fonts matched by an acceptfont element are "whitelisted"; such fonts are
-explicitly included in the set of fonts used to resolve list and match
-requests; including them in this list protects them from being "blacklisted"
-by a rejectfont element. Acceptfont elements include glob and pattern
-elements which are used to match fonts.
- </para></refsect2>
- <refsect2><title><literal>&lt;rejectfont&gt;</literal></title><para>
-Fonts matched by an rejectfont element are "blacklisted"; such fonts are
-excluded from the set of fonts used to resolve list and match requests as if
-they didn't exist in the system. Rejectfont elements include glob and
-pattern elements which are used to match fonts.
- </para></refsect2>
- <refsect2><title><literal>&lt;glob&gt;</literal></title><para>
-Glob elements hold shell-style filename matching patterns (including ? and
-*) which match fonts based on their complete pathnames. This can be used to
-exclude a set of directories (/usr/share/fonts/uglyfont*), or particular
-font file types (*.pcf.gz), but the latter mechanism relies rather heavily
-on filenaming conventions which can't be relied upon. Note that globs
-only apply to directories, not to individual fonts.
- </para></refsect2>
- <refsect2><title><literal>&lt;pattern&gt;</literal></title><para>
-Pattern elements perform list-style matching on incoming fonts; that is,
-they hold a list of elements and associated values. If all of those
-elements have a matching value, then the pattern matches the font. This can
-be used to select fonts based on attributes of the font (scalable, bold,
-etc), which is a more reliable mechanism than using file extensions.
-Pattern elements include patelt elements.
- </para></refsect2>
- <refsect2><title><literal>&lt;patelt name="property"&gt;</literal></title><para>
-Patelt elements hold a single pattern element and list of values. They must
-have a 'name' attribute which indicates the pattern element name. Patelt
-elements include int, double, string, matrix, bool, charset and const
-elements.
- </para></refsect2>
- <refsect2><title><literal>&lt;match target="pattern"&gt;</literal></title><para>
-This element holds first a (possibly empty) list of <literal>&lt;test&gt;</literal> elements and then
-a (possibly empty) list of <literal>&lt;edit&gt;</literal> elements. Patterns which match all of the
-tests are subjected to all the edits. If 'target' is set to "font" instead
-of the default "pattern", then this element applies to the font name
-resulting from a match rather than a font pattern to be matched. If 'target'
-is set to "scan", then this element applies when the font is scanned to
-build the fontconfig database.
- </para></refsect2>
- <refsect2><title><literal>&lt;test qual="any" name="property" target="default" compare="eq"&gt;</literal></title><para>
-This element contains a single value which is compared with the target
-('pattern', 'font', 'scan' or 'default') property "property" (substitute any of the property names seen
-above). 'compare' can be one of "eq", "not_eq", "less", "less_eq", "more", or
-"more_eq". 'qual' may either be the default, "any", in which case the match
-succeeds if any value associated with the property matches the test value, or
-"all", in which case all of the values associated with the property must
-match the test value. When used in a &lt;match target="font"&gt; element,
-the target= attribute in the &lt;test&gt; element selects between matching
-the original pattern or the font. "default" selects whichever target the
-outer &lt;match&gt; element has selected.
- </para></refsect2>
- <refsect2><title><literal>&lt;edit name="property" mode="assign" binding="weak"&gt;</literal></title><para>
-This element contains a list of expression elements (any of the value or
-operator elements). The expression elements are evaluated at run-time and
-modify the property "property". The modification depends on whether
-"property" was matched by one of the associated <literal>&lt;test&gt;</literal> elements, if so, the
-modification may affect the first matched value. Any values inserted into
-the property are given the indicated binding ("strong", "weak" or "same")
-with "same" binding using the value from the matched pattern element.
-'mode' is one of:
- <programlisting>
- Mode With Match Without Match
- ---------------------------------------------------------------------
- "assign" Replace matching value Replace all values
- "assign_replace" Replace all values Replace all values
- "prepend" Insert before matching Insert at head of list
- "prepend_first" Insert at head of list Insert at head of list
- "append" Append after matching Append at end of list
- "append_last" Append at end of list Append at end of list
- </programlisting>
- </para></refsect2>
- <refsect2><title><literal>&lt;int&gt;</literal>, <literal>&lt;double&gt;</literal>, <literal>&lt;string&gt;</literal>, <literal>&lt;bool&gt;</literal></title><para>
-These elements hold a single value of the indicated type. <literal>&lt;bool&gt;</literal>
-elements hold either true or false. An important limitation exists in
-the parsing of floating point numbers -- fontconfig requires that
-the mantissa start with a digit, not a decimal point, so insert a leading
-zero for purely fractional values (e.g. use 0.5 instead of .5 and -0.5
-instead of -.5).
- </para></refsect2>
- <refsect2><title><literal>&lt;matrix&gt;</literal></title><para>
-This element holds the four <literal>&lt;double&gt;</literal> elements of an affine
-transformation.
- </para></refsect2>
- <refsect2><title><literal>&lt;name&gt;</literal></title><para>
-Holds a property name. Evaluates to the first value from the property of
-the font, not the pattern.
- </para></refsect2>
- <refsect2><title><literal>&lt;const&gt;</literal></title><para>
-Holds the name of a constant; these are always integers and serve as
-symbolic names for common font values:
- <programlisting>
- Constant Property Value
- -------------------------------------
- thin weight 0
- extralight weight 40
- ultralight weight 40
- light weight 50
- book weight 75
- regular weight 80
- normal weight 80
- medium weight 100
- demibold weight 180
- semibold weight 180
- bold weight 200
- extrabold weight 205
- black weight 210
- heavy weight 210
- roman slant 0
- italic slant 100
- oblique slant 110
- ultracondensed width 50
- extracondensed width 63
- condensed width 75
- semicondensed width 87
- normal width 100
- semiexpanded width 113
- expanded width 125
- extraexpanded width 150
- ultraexpanded width 200
- proportional spacing 0
- dual spacing 90
- mono spacing 100
- charcell spacing 110
- unknown rgba 0
- rgb rgba 1
- bgr rgba 2
- vrgb rgba 3
- vbgr rgba 4
- none rgba 5
- lcdnone lcdfilter 0
- lcddefault lcdfilter 1
- lcdlight lcdfilter 2
- lcdlegacy lcdfilter 3
- hintnone hintstyle 0
- hintslight hintstyle 1
- hintmedium hintstyle 2
- hintfull hintstyle 3
- </programlisting>
- </para>
- </refsect2>
- <refsect2>
- <title><literal>&lt;or&gt;</literal>, <literal>&lt;and&gt;</literal>, <literal>&lt;plus&gt;</literal>, <literal>&lt;minus&gt;</literal>, <literal>&lt;times&gt;</literal>, <literal>&lt;divide&gt;</literal></title>
- <para>
-These elements perform the specified operation on a list of expression
-elements. <literal>&lt;or&gt;</literal> and <literal>&lt;and&gt;</literal> are boolean, not bitwise.
- </para>
- </refsect2>
- <refsect2>
- <title><literal>&lt;eq&gt;</literal>, <literal>&lt;not_eq&gt;</literal>, <literal>&lt;less&gt;</literal>, <literal>&lt;less_eq&gt;</literal>, <literal>&lt;more&gt;</literal>, <literal>&lt;more_eq&gt;</literal></title>
- <para>
-These elements compare two values, producing a boolean result.
- </para></refsect2>
- <refsect2><title><literal>&lt;not&gt;</literal></title><para>
-Inverts the boolean sense of its one expression element
- </para></refsect2>
- <refsect2><title><literal>&lt;if&gt;</literal></title><para>
-This element takes three expression elements; if the value of the first is
-true, it produces the value of the second, otherwise it produces the value
-of the third.
- </para></refsect2>
- <refsect2><title><literal>&lt;alias&gt;</literal></title><para>
-Alias elements provide a shorthand notation for the set of common match
-operations needed to substitute one font family for another. They contain a
-<literal>&lt;family&gt;</literal> element followed by optional <literal>&lt;prefer&gt;</literal>, <literal>&lt;accept&gt;</literal> and <literal>&lt;default&gt;</literal>
-elements. Fonts matching the <literal>&lt;family&gt;</literal> element are edited to prepend the
-list of <literal>&lt;prefer&gt;</literal>ed families before the matching <literal>&lt;family&gt;</literal>, append the
-<literal>&lt;accept&gt;</literal>able families after the matching <literal>&lt;family&gt;</literal> and append the <literal>&lt;default&gt;</literal>
-families to the end of the family list.
- </para></refsect2>
- <refsect2><title><literal>&lt;family&gt;</literal></title><para>
-Holds a single font family name
- </para></refsect2>
- <refsect2><title><literal>&lt;prefer&gt;</literal>, <literal>&lt;accept&gt;</literal>, <literal>&lt;default&gt;</literal></title><para>
-These hold a list of <literal>&lt;family&gt;</literal> elements to be used by the <literal>&lt;alias&gt;</literal> element.
- </para></refsect2>
-</refsect1>
-<refsect1><title>EXAMPLE CONFIGURATION FILE</title>
- <refsect2><title>System configuration file</title>
- <para>
-This is an example of a system-wide configuration file
- </para>
- <programlisting>
-&lt;?xml version="1.0"?&gt;
-&lt;!DOCTYPE fontconfig SYSTEM "fonts.dtd"&gt;
-&lt;!-- &confdir;/fonts.conf file to configure system font access --&gt;
-&lt;fontconfig&gt;
-&lt;!--
- Find fonts in these directories
---&gt;
-&lt;dir&gt;/usr/share/fonts&lt;/dir&gt;
-&lt;dir&gt;/usr/X11R6/lib/X11/fonts&lt;/dir&gt;
-
-&lt;!--
- Accept deprecated 'mono' alias, replacing it with 'monospace'
---&gt;
-&lt;match target="pattern"&gt;
- &lt;test qual="any" name="family"&gt;&lt;string&gt;mono&lt;/string&gt;&lt;/test&gt;
- &lt;edit name="family" mode="assign"&gt;&lt;string&gt;monospace&lt;/string&gt;&lt;/edit&gt;
-&lt;/match&gt;
-
-&lt;!--
- Names not including any well known alias are given 'sans'
---&gt;
-&lt;match target="pattern"&gt;
- &lt;test qual="all" name="family" mode="not_eq"&gt;sans&lt;/test&gt;
- &lt;test qual="all" name="family" mode="not_eq"&gt;serif&lt;/test&gt;
- &lt;test qual="all" name="family" mode="not_eq"&gt;monospace&lt;/test&gt;
- &lt;edit name="family" mode="append_last"&gt;&lt;string&gt;sans&lt;/string&gt;&lt;/edit&gt;
-&lt;/match&gt;
-
-&lt;!--
- Load per-user customization file, but don't complain
- if it doesn't exist
---&gt;
-&lt;include ignore_missing="yes"&gt;~/.fonts.conf&lt;/include&gt;
-
-&lt;!--
- Load local customization files, but don't complain
- if there aren't any
---&gt;
-&lt;include ignore_missing="yes"&gt;conf.d&lt;/include&gt;
-&lt;include ignore_missing="yes"&gt;local.conf&lt;/include&gt;
-
-&lt;!--
- Alias well known font names to available TrueType fonts.
- These substitute TrueType faces for similar Type1
- faces to improve screen appearance.
---&gt;
-&lt;alias&gt;
- &lt;family&gt;Times&lt;/family&gt;
- &lt;prefer&gt;&lt;family&gt;Times New Roman&lt;/family&gt;&lt;/prefer&gt;
- &lt;default&gt;&lt;family&gt;serif&lt;/family&gt;&lt;/default&gt;
-&lt;/alias&gt;
-&lt;alias&gt;
- &lt;family&gt;Helvetica&lt;/family&gt;
- &lt;prefer&gt;&lt;family&gt;Arial&lt;/family&gt;&lt;/prefer&gt;
- &lt;default&gt;&lt;family&gt;sans&lt;/family&gt;&lt;/default&gt;
-&lt;/alias&gt;
-&lt;alias&gt;
- &lt;family&gt;Courier&lt;/family&gt;
- &lt;prefer&gt;&lt;family&gt;Courier New&lt;/family&gt;&lt;/prefer&gt;
- &lt;default&gt;&lt;family&gt;monospace&lt;/family&gt;&lt;/default&gt;
-&lt;/alias&gt;
-
-&lt;!--
- Provide required aliases for standard names
- Do these after the users configuration file so that
- any aliases there are used preferentially
---&gt;
-&lt;alias&gt;
- &lt;family&gt;serif&lt;/family&gt;
- &lt;prefer&gt;&lt;family&gt;Times New Roman&lt;/family&gt;&lt;/prefer&gt;
-&lt;/alias&gt;
-&lt;alias&gt;
- &lt;family&gt;sans&lt;/family&gt;
- &lt;prefer&gt;&lt;family&gt;Arial&lt;/family&gt;&lt;/prefer&gt;
-&lt;/alias&gt;
-&lt;alias&gt;
- &lt;family&gt;monospace&lt;/family&gt;
- &lt;prefer&gt;&lt;family&gt;Andale Mono&lt;/family&gt;&lt;/prefer&gt;
-&lt;/alias&gt;
-&lt;/fontconfig&gt;
- </programlisting>
- </refsect2>
- <refsect2><title>User configuration file</title>
- <para>
-This is an example of a per-user configuration file that lives in
-~/.fonts.conf
- </para>
- <programlisting>
-&lt;?xml version="1.0"?&gt;
-&lt;!DOCTYPE fontconfig SYSTEM "fonts.dtd"&gt;
-&lt;!-- ~/.fonts.conf for per-user font configuration --&gt;
-&lt;fontconfig&gt;
-
-&lt;!--
- Private font directory
---&gt;
-&lt;dir&gt;~/.fonts&lt;/dir&gt;
-
-&lt;!--
- use rgb sub-pixel ordering to improve glyph appearance on
- LCD screens. Changes affecting rendering, but not matching
- should always use target="font".
---&gt;
-&lt;match target="font"&gt;
- &lt;edit name="rgba" mode="assign"&gt;&lt;const&gt;rgb&lt;/const&gt;&lt;/edit&gt;
-&lt;/match&gt;
-&lt;/fontconfig&gt;
- </programlisting>
- </refsect2>
-</refsect1>
-<refsect1><title>Files</title>
- <para>
-<emphasis>fonts.conf</emphasis>
-contains configuration information for the fontconfig library
-consisting of directories to look at for font information as well as
-instructions on editing program specified font patterns before attempting to
-match the available fonts. It is in xml format.
- </para>
- <para>
-<emphasis>conf.d</emphasis>
-is the conventional name for a directory of additional configuration files
-managed by external applications or the local administrator. The
-filenames starting with decimal digits are sorted in lexicographic order
-and used as additional configuration files. All of these files are in xml
-format. The master fonts.conf file references this directory in an
-&lt;include&gt; directive.
- </para>
- <para>
-<emphasis>fonts.dtd</emphasis>
-is a DTD that describes the format of the configuration files.
- </para>
- <para>
-<emphasis>~/.fonts.conf.d</emphasis>
-is the conventional name for a per-user directory of (typically
-auto-generated) configuration files, although the
-actual location is specified in the global fonts.conf file.
- </para>
- <para>
-<emphasis>~/.fonts.conf</emphasis>
-is the conventional location for per-user font configuration, although the
-actual location is specified in the global fonts.conf file.
- </para>
- <para>
-<emphasis> ~/.fonts.cache-*</emphasis>
-is the conventional repository of font information that isn't found in the
-per-directory caches. This file is automatically maintained by fontconfig.
- </para>
-</refsect1>
-<refsect1><title>See Also</title>
- <para>
-fc-cat(1), fc-cache(1), fc-list(1), fc-match(1), fc-query(1)
- </para>
-</refsect1>
-<refsect1><title>Version</title>
- <para>
-Fontconfig version &version;
- </para>
-</refsect1>
-</refentry>
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V3.1//EN" [
+<!ENTITY version SYSTEM "version.sgml">
+<!ENTITY confdir SYSTEM "confdir.sgml">
+]>
+<!--
+ Copyright © 2003 Keith Packard
+
+ Permission to use, copy, modify, distribute, and sell this software and its
+ documentation for any purpose is hereby granted without fee, provided that
+ the above copyright notice appear in all copies and that both that
+ copyright notice and this permission notice appear in supporting
+ documentation, and that the name of the author(s) not be used in
+ advertising or publicity pertaining to distribution of the software without
+ specific, written prior permission. The authors make no
+ representations about the suitability of this software for any purpose. It
+ is provided "as is" without express or implied warranty.
+
+ THE AUTHOR(S) DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ PERFORMANCE OF THIS SOFTWARE.
+-->
+<refentry>
+<refmeta>
+ <refentrytitle>fonts-conf</refentrytitle>
+ <manvolnum>5</manvolnum>
+</refmeta>
+<refnamediv>
+ <refname>fonts.conf</refname>
+ <refpurpose>Font configuration files</refpurpose>
+</refnamediv>
+<refsynopsisdiv>
+<synopsis>
+ &confdir;/fonts.conf
+ &confdir;/fonts.dtd
+ &confdir;/conf.d
+ ~/.fonts.conf.d
+ ~/.fonts.conf
+</synopsis>
+</refsynopsisdiv>
+<refsect1><title>Description</title>
+ <para>
+Fontconfig is a library designed to provide system-wide font configuration,
+customization and application access.
+ </para>
+</refsect1>
+<refsect1><title>Functional Overview</title>
+ <para>
+Fontconfig contains two essential modules, the configuration module which
+builds an internal configuration from XML files and the matching module
+which accepts font patterns and returns the nearest matching font.
+ </para>
+ <refsect2><title>Font Configuration</title>
+ <para>
+The configuration module consists of the FcConfig datatype, libexpat and
+FcConfigParse which walks over an XML tree and amends a configuration with
+data found within. From an external perspective, configuration of the
+library consists of generating a valid XML tree and feeding that to
+FcConfigParse. The only other mechanism provided to applications for
+changing the running configuration is to add fonts and directories to the
+list of application-provided font files.
+ </para><para>
+The intent is to make font configurations relatively static, and shared by
+as many applications as possible. It is hoped that this will lead to more
+stable font selection when passing names from one application to another.
+XML was chosen as a configuration file format because it provides a format
+which is easy for external agents to edit while retaining the correct
+structure and syntax.
+ </para><para>
+Font configuration is separate from font matching; applications needing to
+do their own matching can access the available fonts from the library and
+perform private matching. The intent is to permit applications to pick and
+choose appropriate functionality from the library instead of forcing them to
+choose between this library and a private configuration mechanism. The hope
+is that this will ensure that configuration of fonts for all applications
+can be centralized in one place. Centralizing font configuration will
+simplify and regularize font installation and customization.
+ </para>
+ </refsect2>
+ <refsect2>
+ <title>Font Properties</title>
+ <para>
+While font patterns may contain essentially any properties, there are some
+well known properties with associated types. Fontconfig uses some of these
+properties for font matching and font completion. Others are provided as a
+convenience for the applications' rendering mechanism.
+ </para>
+ <programlisting>
+ Property Type Description
+ --------------------------------------------------------------
+ family String Font family names
+ familylang String Languages corresponding to each family
+ style String Font style. Overrides weight and slant
+ stylelang String Languages corresponding to each style
+ fullname String Font full names (often includes style)
+ fullnamelang String Languages corresponding to each fullname
+ slant Int Italic, oblique or roman
+ weight Int Light, medium, demibold, bold or black
+ size Double Point size
+ width Int Condensed, normal or expanded
+ aspect Double Stretches glyphs horizontally before hinting
+ pixelsize Double Pixel size
+ spacing Int Proportional, dual-width, monospace or charcell
+ foundry String Font foundry name
+ antialias Bool Whether glyphs can be antialiased
+ hinting Bool Whether the rasterizer should use hinting
+ hintstyle Int Automatic hinting style
+ verticallayout Bool Use vertical layout
+ autohint Bool Use autohinter instead of normal hinter
+ globaladvance Bool Use font global advance data
+ file String The filename holding the font
+ index Int The index of the font within the file
+ ftface FT_Face Use the specified FreeType face object
+ rasterizer String Which rasterizer is in use
+ outline Bool Whether the glyphs are outlines
+ scalable Bool Whether glyphs can be scaled
+ scale Double Scale factor for point->pixel conversions
+ dpi Double Target dots per inch
+ rgba Int unknown, rgb, bgr, vrgb, vbgr,
+ none - subpixel geometry
+ lcdfilter Int Type of LCD filter
+ minspace Bool Eliminate leading from line spacing
+ charset CharSet Unicode chars encoded by the font
+ lang String List of RFC-3066-style languages this
+ font supports
+ fontversion Int Version number of the font
+ capability String List of layout capabilities in the font
+ embolden Bool Rasterizer should synthetically embolden the font
+ </programlisting>
+ </refsect2>
+ <refsect2>
+ <title>Font Matching</title>
+ <para>
+Fontconfig performs matching by measuring the distance from a provided
+pattern to all of the available fonts in the system. The closest matching
+font is selected. This ensures that a font will always be returned, but
+doesn't ensure that it is anything like the requested pattern.
+ </para><para>
+Font matching starts with an application constructed pattern. The desired
+attributes of the resulting font are collected together in a pattern. Each
+property of the pattern can contain one or more values; these are listed in
+priority order; matches earlier in the list are considered "closer" than
+matches later in the list.
+ </para><para>
+The initial pattern is modified by applying the list of editing instructions
+specific to patterns found in the configuration; each consists of a match
+predicate and a set of editing operations. They are executed in the order
+they appeared in the configuration. Each match causes the associated
+sequence of editing operations to be applied.
+ </para><para>
+After the pattern has been edited, a sequence of default substitutions are
+performed to canonicalize the set of available properties; this avoids the
+need for the lower layers to constantly provide default values for various
+font properties during rendering.
+ </para><para>
+The canonical font pattern is finally matched against all available fonts.
+The distance from the pattern to the font is measured for each of several
+properties: foundry, charset, family, lang, spacing, pixelsize, style,
+slant, weight, antialias, rasterizer and outline. This list is in priority
+order -- results of comparing earlier elements of this list weigh more
+heavily than later elements.
+ </para><para>
+There is one special case to this rule; family names are split into two
+bindings; strong and weak. Strong family names are given greater precedence
+in the match than lang elements while weak family names are given lower
+precedence than lang elements. This permits the document language to drive
+font selection when any document specified font is unavailable.
+ </para><para>
+The pattern representing that font is augmented to include any properties
+found in the pattern but not found in the font itself; this permits the
+application to pass rendering instructions or any other data through the
+matching system. Finally, the list of editing instructions specific to
+fonts found in the configuration are applied to the pattern. This modified
+pattern is returned to the application.
+ </para><para>
+The return value contains sufficient information to locate and rasterize the
+font, including the file name, pixel size and other rendering data. As
+none of the information involved pertains to the FreeType library,
+applications are free to use any rasterization engine or even to take
+the identified font file and access it directly.
+ </para><para>
+The match/edit sequences in the configuration are performed in two passes
+because there are essentially two different operations necessary -- the
+first is to modify how fonts are selected; aliasing families and adding
+suitable defaults. The second is to modify how the selected fonts are
+rasterized. Those must apply to the selected font, not the original pattern
+as false matches will often occur.
+ </para>
+ </refsect2>
+ <refsect2><title>Font Names</title>
+ <para>
+Fontconfig provides a textual representation for patterns that the library
+can both accept and generate. The representation is in three parts, first a
+list of family names, second a list of point sizes and finally a list of
+additional properties:
+ </para>
+ <programlisting>
+ &lt;families&gt;-&lt;point sizes&gt;:&lt;name1&gt;=&lt;values1&gt;:&lt;name2&gt;=&lt;values2&gt;...
+ </programlisting>
+ <para>
+Values in a list are separated with commas. The name needn't include either
+families or point sizes; they can be elided. In addition, there are
+symbolic constants that simultaneously indicate both a name and a value.
+Here are some examples:
+ </para>
+ <programlisting>
+ Name Meaning
+ ----------------------------------------------------------
+ Times-12 12 point Times Roman
+ Times-12:bold 12 point Times Bold
+ Courier:italic Courier Italic in the default size
+ Monospace:matrix=1 .1 0 1 The users preferred monospace font
+ with artificial obliquing
+ </programlisting>
+ <para>
+The '\', '-', ':' and ',' characters in family names must be preceded by a
+'\' character to avoid having them misinterpreted. Similarly, values
+containing '\', '=', '_', ':' and ',' must also have them preceded by a
+'\' character. The '\' characters are stripped out of the family name and
+values as the font name is read.
+ </para>
+ </refsect2>
+</refsect1>
+<refsect1><title>Debugging Applications</title>
+ <para>
+To help diagnose font and applications problems, fontconfig is built with a
+large amount of internal debugging left enabled. It is controlled by means
+of the FC_DEBUG environment variable. The value of this variable is
+interpreted as a number, and each bit within that value controls different
+debugging messages.
+ </para>
+ <programlisting>
+ Name Value Meaning
+ ---------------------------------------------------------
+ MATCH 1 Brief information about font matching
+ MATCHV 2 Extensive font matching information
+ EDIT 4 Monitor match/test/edit execution
+ FONTSET 8 Track loading of font information at startup
+ CACHE 16 Watch cache files being written
+ CACHEV 32 Extensive cache file writing information
+ PARSE 64 (no longer in use)
+ SCAN 128 Watch font files being scanned to build caches
+ SCANV 256 Verbose font file scanning information
+ MEMORY 512 Monitor fontconfig memory usage
+ CONFIG 1024 Monitor which config files are loaded
+ LANGSET 2048 Dump char sets used to construct lang values
+ OBJTYPES 4096 Display message when value typechecks fail
+ </programlisting>
+ <para>
+Add the value of the desired debug levels together and assign that (in
+base 10) to the FC_DEBUG environment variable before running the
+application. Output from these statements is sent to stdout.
+ </para>
+</refsect1>
+<refsect1><title>Lang Tags</title>
+ <para>
+Each font in the database contains a list of languages it supports. This is
+computed by comparing the Unicode coverage of the font with the orthography
+of each language. Languages are tagged using an RFC-3066 compatible naming
+and occur in two parts -- the ISO 639 language tag followed a hyphen and then
+by the ISO 3166 country code. The hyphen and country code may be elided.
+ </para><para>
+Fontconfig has orthographies for several languages built into the library.
+No provision has been made for adding new ones aside from rebuilding the
+library. It currently supports 122 of the 139 languages named in ISO 639-1,
+141 of the languages with two-letter codes from ISO 639-2 and another 30
+languages with only three-letter codes. Languages with both two and three
+letter codes are provided with only the two letter code.
+ </para><para>
+For languages used in multiple territories with radically different
+character sets, fontconfig includes per-territory orthographies. This
+includes Azerbaijani, Kurdish, Pashto, Tigrinya and Chinese.
+ </para>
+</refsect1>
+<refsect1><title>Configuration File Format</title>
+ <para>
+Configuration files for fontconfig are stored in XML format; this
+format makes external configuration tools easier to write and ensures that
+they will generate syntactically correct configuration files. As XML
+files are plain text, they can also be manipulated by the expert user using
+a text editor.
+ </para><para>
+The fontconfig document type definition resides in the external entity
+"fonts.dtd"; this is normally stored in the default font configuration
+directory (&confdir;). Each configuration file should contain the
+following structure:
+ <programlisting>
+ &lt;?xml version="1.0"?&gt;
+ &lt;!DOCTYPE fontconfig SYSTEM "fonts.dtd"&gt;
+ &lt;fontconfig&gt;
+ ...
+ &lt;/fontconfig&gt;
+ </programlisting>
+ </para>
+<refsect2><title><literal>&lt;fontconfig&gt;</literal></title><para>
+This is the top level element for a font configuration and can contain
+<literal>&lt;dir&gt;</literal>, <literal>&lt;cache&gt;</literal>, <literal>&lt;include&gt;</literal>, <literal>&lt;match&gt;</literal> and <literal>&lt;alias&gt;</literal> elements in any order.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;dir&gt;</literal></title><para>
+This element contains a directory name which will be scanned for font files
+to include in the set of available fonts.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;cache&gt;</literal></title><para>
+This element contains a file name for the per-user cache of font
+information. If it starts with '~', it refers to a file in the users
+home directory. This file is used to hold information about fonts that
+isn't present in the per-directory cache files. It is automatically
+maintained by the fontconfig library. The default for this file
+is ``~/.fonts.cache-<literal>&lt;version&gt;</literal>'', where <literal>&lt;version&gt;</literal> is the font configuration
+file version number (currently 2).
+ </para></refsect2>
+ <refsect2><title><literal>&lt;include ignore_missing="no"&gt;</literal></title><para>
+This element contains the name of an additional configuration file or
+directory. If a directory, every file within that directory starting with an
+ASCII digit (U+0030 - U+0039) and ending with the string ``.conf'' will be processed in sorted order. When
+the XML datatype is traversed by FcConfigParse, the contents of the file(s)
+will also be incorporated into the configuration by passing the filename(s) to
+FcConfigLoadAndParse. If 'ignore_missing' is set to "yes" instead of the
+default "no", a missing file or directory will elicit no warning message from
+the library.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;config&gt;</literal></title><para>
+This element provides a place to consolidate additional configuration
+information. <literal>&lt;config&gt;</literal> can contain <literal>&lt;blank&gt;</literal> and <literal>&lt;rescan&gt;</literal> elements in any
+order.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;blank&gt;</literal></title><para>
+Fonts often include "broken" glyphs which appear in the encoding but are
+drawn as blanks on the screen. Within the <literal>&lt;blank&gt;</literal> element, place each
+Unicode characters which is supposed to be blank in an <literal>&lt;int&gt;</literal> element.
+Characters outside of this set which are drawn as blank will be elided from
+the set of characters supported by the font.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;rescan&gt;</literal></title><para>
+The <literal>&lt;rescan&gt;</literal> element holds an <literal>&lt;int&gt;</literal> element which indicates the default
+interval between automatic checks for font configuration changes.
+Fontconfig will validate all of the configuration files and directories and
+automatically rebuild the internal datastructures when this interval passes.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;selectfont&gt;</literal></title><para>
+This element is used to black/white list fonts from being listed or matched
+against. It holds acceptfont and rejectfont elements.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;acceptfont&gt;</literal></title><para>
+Fonts matched by an acceptfont element are "whitelisted"; such fonts are
+explicitly included in the set of fonts used to resolve list and match
+requests; including them in this list protects them from being "blacklisted"
+by a rejectfont element. Acceptfont elements include glob and pattern
+elements which are used to match fonts.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;rejectfont&gt;</literal></title><para>
+Fonts matched by an rejectfont element are "blacklisted"; such fonts are
+excluded from the set of fonts used to resolve list and match requests as if
+they didn't exist in the system. Rejectfont elements include glob and
+pattern elements which are used to match fonts.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;glob&gt;</literal></title><para>
+Glob elements hold shell-style filename matching patterns (including ? and
+*) which match fonts based on their complete pathnames. This can be used to
+exclude a set of directories (/usr/share/fonts/uglyfont*), or particular
+font file types (*.pcf.gz), but the latter mechanism relies rather heavily
+on filenaming conventions which can't be relied upon. Note that globs
+only apply to directories, not to individual fonts.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;pattern&gt;</literal></title><para>
+Pattern elements perform list-style matching on incoming fonts; that is,
+they hold a list of elements and associated values. If all of those
+elements have a matching value, then the pattern matches the font. This can
+be used to select fonts based on attributes of the font (scalable, bold,
+etc), which is a more reliable mechanism than using file extensions.
+Pattern elements include patelt elements.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;patelt name="property"&gt;</literal></title><para>
+Patelt elements hold a single pattern element and list of values. They must
+have a 'name' attribute which indicates the pattern element name. Patelt
+elements include int, double, string, matrix, bool, charset and const
+elements.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;match target="pattern"&gt;</literal></title><para>
+This element holds first a (possibly empty) list of <literal>&lt;test&gt;</literal> elements and then
+a (possibly empty) list of <literal>&lt;edit&gt;</literal> elements. Patterns which match all of the
+tests are subjected to all the edits. If 'target' is set to "font" instead
+of the default "pattern", then this element applies to the font name
+resulting from a match rather than a font pattern to be matched. If 'target'
+is set to "scan", then this element applies when the font is scanned to
+build the fontconfig database.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;test qual="any" name="property" target="default" compare="eq"&gt;</literal></title><para>
+This element contains a single value which is compared with the target
+('pattern', 'font', 'scan' or 'default') property "property" (substitute any of the property names seen
+above). 'compare' can be one of "eq", "not_eq", "less", "less_eq", "more", or
+"more_eq". 'qual' may either be the default, "any", in which case the match
+succeeds if any value associated with the property matches the test value, or
+"all", in which case all of the values associated with the property must
+match the test value. When used in a &lt;match target="font"&gt; element,
+the target= attribute in the &lt;test&gt; element selects between matching
+the original pattern or the font. "default" selects whichever target the
+outer &lt;match&gt; element has selected.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;edit name="property" mode="assign" binding="weak"&gt;</literal></title><para>
+This element contains a list of expression elements (any of the value or
+operator elements). The expression elements are evaluated at run-time and
+modify the property "property". The modification depends on whether
+"property" was matched by one of the associated <literal>&lt;test&gt;</literal> elements, if so, the
+modification may affect the first matched value. Any values inserted into
+the property are given the indicated binding ("strong", "weak" or "same")
+with "same" binding using the value from the matched pattern element.
+'mode' is one of:
+ <programlisting>
+ Mode With Match Without Match
+ ---------------------------------------------------------------------
+ "assign" Replace matching value Replace all values
+ "assign_replace" Replace all values Replace all values
+ "prepend" Insert before matching Insert at head of list
+ "prepend_first" Insert at head of list Insert at head of list
+ "append" Append after matching Append at end of list
+ "append_last" Append at end of list Append at end of list
+ </programlisting>
+ </para></refsect2>
+ <refsect2><title><literal>&lt;int&gt;</literal>, <literal>&lt;double&gt;</literal>, <literal>&lt;string&gt;</literal>, <literal>&lt;bool&gt;</literal></title><para>
+These elements hold a single value of the indicated type. <literal>&lt;bool&gt;</literal>
+elements hold either true or false. An important limitation exists in
+the parsing of floating point numbers -- fontconfig requires that
+the mantissa start with a digit, not a decimal point, so insert a leading
+zero for purely fractional values (e.g. use 0.5 instead of .5 and -0.5
+instead of -.5).
+ </para></refsect2>
+ <refsect2><title><literal>&lt;matrix&gt;</literal></title><para>
+This element holds the four <literal>&lt;double&gt;</literal> elements of an affine
+transformation.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;range&gt;</literal></title><para>
+This element holds the two <literal>&lt;int&gt;</literal> elements of a range
+representation.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;charset&gt;</literal></title><para>
+This element holds at least one <literal>&lt;int&gt;</literal> element of
+an Unicode code point or more.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;langset&gt;</literal></title><para>
+This element holds at least one <literal>&lt;string&gt;</literal> element of
+a RFC-3066-style languages or more.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;name&gt;</literal></title><para>
+Holds a property name. Evaluates to the first value from the property of
+the font, not the pattern.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;const&gt;</literal></title><para>
+Holds the name of a constant; these are always integers and serve as
+symbolic names for common font values:
+ <programlisting>
+ Constant Property Value
+ -------------------------------------
+ thin weight 0
+ extralight weight 40
+ ultralight weight 40
+ light weight 50
+ book weight 75
+ regular weight 80
+ normal weight 80
+ medium weight 100
+ demibold weight 180
+ semibold weight 180
+ bold weight 200
+ extrabold weight 205
+ black weight 210
+ heavy weight 210
+ roman slant 0
+ italic slant 100
+ oblique slant 110
+ ultracondensed width 50
+ extracondensed width 63
+ condensed width 75
+ semicondensed width 87
+ normal width 100
+ semiexpanded width 113
+ expanded width 125
+ extraexpanded width 150
+ ultraexpanded width 200
+ proportional spacing 0
+ dual spacing 90
+ mono spacing 100
+ charcell spacing 110
+ unknown rgba 0
+ rgb rgba 1
+ bgr rgba 2
+ vrgb rgba 3
+ vbgr rgba 4
+ none rgba 5
+ lcdnone lcdfilter 0
+ lcddefault lcdfilter 1
+ lcdlight lcdfilter 2
+ lcdlegacy lcdfilter 3
+ hintnone hintstyle 0
+ hintslight hintstyle 1
+ hintmedium hintstyle 2
+ hintfull hintstyle 3
+ </programlisting>
+ </para>
+ </refsect2>
+ <refsect2>
+ <title><literal>&lt;or&gt;</literal>, <literal>&lt;and&gt;</literal>, <literal>&lt;plus&gt;</literal>, <literal>&lt;minus&gt;</literal>, <literal>&lt;times&gt;</literal>, <literal>&lt;divide&gt;</literal></title>
+ <para>
+These elements perform the specified operation on a list of expression
+elements. <literal>&lt;or&gt;</literal> and <literal>&lt;and&gt;</literal> are boolean, not bitwise.
+ </para>
+ </refsect2>
+ <refsect2>
+ <title><literal>&lt;eq&gt;</literal>, <literal>&lt;not_eq&gt;</literal>, <literal>&lt;less&gt;</literal>, <literal>&lt;less_eq&gt;</literal>, <literal>&lt;more&gt;</literal>, <literal>&lt;more_eq&gt;</literal></title>
+ <para>
+These elements compare two values, producing a boolean result.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;not&gt;</literal></title><para>
+Inverts the boolean sense of its one expression element
+ </para></refsect2>
+ <refsect2><title><literal>&lt;if&gt;</literal></title><para>
+This element takes three expression elements; if the value of the first is
+true, it produces the value of the second, otherwise it produces the value
+of the third.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;alias&gt;</literal></title><para>
+Alias elements provide a shorthand notation for the set of common match
+operations needed to substitute one font family for another. They contain a
+<literal>&lt;family&gt;</literal> element followed by optional <literal>&lt;prefer&gt;</literal>, <literal>&lt;accept&gt;</literal> and <literal>&lt;default&gt;</literal>
+elements. Fonts matching the <literal>&lt;family&gt;</literal> element are edited to prepend the
+list of <literal>&lt;prefer&gt;</literal>ed families before the matching <literal>&lt;family&gt;</literal>, append the
+<literal>&lt;accept&gt;</literal>able families after the matching <literal>&lt;family&gt;</literal> and append the <literal>&lt;default&gt;</literal>
+families to the end of the family list.
+ </para></refsect2>
+ <refsect2><title><literal>&lt;family&gt;</literal></title><para>
+Holds a single font family name
+ </para></refsect2>
+ <refsect2><title><literal>&lt;prefer&gt;</literal>, <literal>&lt;accept&gt;</literal>, <literal>&lt;default&gt;</literal></title><para>
+These hold a list of <literal>&lt;family&gt;</literal> elements to be used by the <literal>&lt;alias&gt;</literal> element.
+ </para></refsect2>
+</refsect1>
+<refsect1><title>EXAMPLE CONFIGURATION FILE</title>
+ <refsect2><title>System configuration file</title>
+ <para>
+This is an example of a system-wide configuration file
+ </para>
+ <programlisting>
+&lt;?xml version="1.0"?&gt;
+&lt;!DOCTYPE fontconfig SYSTEM "fonts.dtd"&gt;
+&lt;!-- &confdir;/fonts.conf file to configure system font access --&gt;
+&lt;fontconfig&gt;
+&lt;!--
+ Find fonts in these directories
+--&gt;
+&lt;dir&gt;/usr/share/fonts&lt;/dir&gt;
+&lt;dir&gt;/usr/X11R6/lib/X11/fonts&lt;/dir&gt;
+
+&lt;!--
+ Accept deprecated 'mono' alias, replacing it with 'monospace'
+--&gt;
+&lt;match target="pattern"&gt;
+ &lt;test qual="any" name="family"&gt;&lt;string&gt;mono&lt;/string&gt;&lt;/test&gt;
+ &lt;edit name="family" mode="assign"&gt;&lt;string&gt;monospace&lt;/string&gt;&lt;/edit&gt;
+&lt;/match&gt;
+
+&lt;!--
+ Names not including any well known alias are given 'sans'
+--&gt;
+&lt;match target="pattern"&gt;
+ &lt;test qual="all" name="family" mode="not_eq"&gt;sans&lt;/test&gt;
+ &lt;test qual="all" name="family" mode="not_eq"&gt;serif&lt;/test&gt;
+ &lt;test qual="all" name="family" mode="not_eq"&gt;monospace&lt;/test&gt;
+ &lt;edit name="family" mode="append_last"&gt;&lt;string&gt;sans&lt;/string&gt;&lt;/edit&gt;
+&lt;/match&gt;
+
+&lt;!--
+ Load per-user customization file, but don't complain
+ if it doesn't exist
+--&gt;
+&lt;include ignore_missing="yes"&gt;~/.fonts.conf&lt;/include&gt;
+
+&lt;!--
+ Load local customization files, but don't complain
+ if there aren't any
+--&gt;
+&lt;include ignore_missing="yes"&gt;conf.d&lt;/include&gt;
+&lt;include ignore_missing="yes"&gt;local.conf&lt;/include&gt;
+
+&lt;!--
+ Alias well known font names to available TrueType fonts.
+ These substitute TrueType faces for similar Type1
+ faces to improve screen appearance.
+--&gt;
+&lt;alias&gt;
+ &lt;family&gt;Times&lt;/family&gt;
+ &lt;prefer&gt;&lt;family&gt;Times New Roman&lt;/family&gt;&lt;/prefer&gt;
+ &lt;default&gt;&lt;family&gt;serif&lt;/family&gt;&lt;/default&gt;
+&lt;/alias&gt;
+&lt;alias&gt;
+ &lt;family&gt;Helvetica&lt;/family&gt;
+ &lt;prefer&gt;&lt;family&gt;Arial&lt;/family&gt;&lt;/prefer&gt;
+ &lt;default&gt;&lt;family&gt;sans&lt;/family&gt;&lt;/default&gt;
+&lt;/alias&gt;
+&lt;alias&gt;
+ &lt;family&gt;Courier&lt;/family&gt;
+ &lt;prefer&gt;&lt;family&gt;Courier New&lt;/family&gt;&lt;/prefer&gt;
+ &lt;default&gt;&lt;family&gt;monospace&lt;/family&gt;&lt;/default&gt;
+&lt;/alias&gt;
+
+&lt;!--
+ Provide required aliases for standard names
+ Do these after the users configuration file so that
+ any aliases there are used preferentially
+--&gt;
+&lt;alias&gt;
+ &lt;family&gt;serif&lt;/family&gt;
+ &lt;prefer&gt;&lt;family&gt;Times New Roman&lt;/family&gt;&lt;/prefer&gt;
+&lt;/alias&gt;
+&lt;alias&gt;
+ &lt;family&gt;sans&lt;/family&gt;
+ &lt;prefer&gt;&lt;family&gt;Arial&lt;/family&gt;&lt;/prefer&gt;
+&lt;/alias&gt;
+&lt;alias&gt;
+ &lt;family&gt;monospace&lt;/family&gt;
+ &lt;prefer&gt;&lt;family&gt;Andale Mono&lt;/family&gt;&lt;/prefer&gt;
+&lt;/alias&gt;
+&lt;/fontconfig&gt;
+ </programlisting>
+ </refsect2>
+ <refsect2><title>User configuration file</title>
+ <para>
+This is an example of a per-user configuration file that lives in
+~/.fonts.conf
+ </para>
+ <programlisting>
+&lt;?xml version="1.0"?&gt;
+&lt;!DOCTYPE fontconfig SYSTEM "fonts.dtd"&gt;
+&lt;!-- ~/.fonts.conf for per-user font configuration --&gt;
+&lt;fontconfig&gt;
+
+&lt;!--
+ Private font directory
+--&gt;
+&lt;dir&gt;~/.fonts&lt;/dir&gt;
+
+&lt;!--
+ use rgb sub-pixel ordering to improve glyph appearance on
+ LCD screens. Changes affecting rendering, but not matching
+ should always use target="font".
+--&gt;
+&lt;match target="font"&gt;
+ &lt;edit name="rgba" mode="assign"&gt;&lt;const&gt;rgb&lt;/const&gt;&lt;/edit&gt;
+&lt;/match&gt;
+&lt;/fontconfig&gt;
+ </programlisting>
+ </refsect2>
+</refsect1>
+<refsect1><title>Files</title>
+ <para>
+<emphasis>fonts.conf</emphasis>
+contains configuration information for the fontconfig library
+consisting of directories to look at for font information as well as
+instructions on editing program specified font patterns before attempting to
+match the available fonts. It is in XML format.
+ </para>
+ <para>
+<emphasis>conf.d</emphasis>
+is the conventional name for a directory of additional configuration files
+managed by external applications or the local administrator. The
+filenames starting with decimal digits are sorted in lexicographic order
+and used as additional configuration files. All of these files are in XML
+format. The master fonts.conf file references this directory in an
+&lt;include&gt; directive.
+ </para>
+ <para>
+<emphasis>fonts.dtd</emphasis>
+is a DTD that describes the format of the configuration files.
+ </para>
+ <para>
+<emphasis>~/.fonts.conf.d</emphasis>
+is the conventional name for a per-user directory of (typically
+auto-generated) configuration files, although the
+actual location is specified in the global fonts.conf file.
+ </para>
+ <para>
+<emphasis>~/.fonts.conf</emphasis>
+is the conventional location for per-user font configuration, although the
+actual location is specified in the global fonts.conf file.
+ </para>
+ <para>
+<emphasis> ~/.fonts.cache-*</emphasis>
+is the conventional repository of font information that isn't found in the
+per-directory caches. This file is automatically maintained by fontconfig.
+ </para>
+</refsect1>
+<refsect1><title>See Also</title>
+ <para>
+fc-cat(1), fc-cache(1), fc-list(1), fc-match(1), fc-query(1)
+ </para>
+</refsect1>
+<refsect1><title>Version</title>
+ <para>
+Fontconfig version &version;
+ </para>
+</refsect1>
+</refentry>