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diff --git a/pthreads/manual/pthread_attr_init.html b/pthreads/manual/pthread_attr_init.html new file mode 100644 index 000000000..fa5ab5811 --- /dev/null +++ b/pthreads/manual/pthread_attr_init.html @@ -0,0 +1,280 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> +<HTML> +<HEAD> + <META HTTP-EQUIV="CONTENT-TYPE" CONTENT="text/html; charset=utf-8"> + <TITLE>PTHREAD_ATTR_INIT(3) manual page</TITLE> + <META NAME="GENERATOR" CONTENT="OpenOffice.org 1.1.3 (Linux)"> + <META NAME="CREATED" CONTENT="20050504;10092900"> + <META NAME="CHANGED" CONTENT="20050505;16540200"> + <!-- manual page source format generated by PolyglotMan v3.2, --> + <!-- available at http://polyglotman.sourceforge.net/ --> +</HEAD> +<BODY LANG="en-GB" BGCOLOR="#ffffff" DIR="LTR"> +<H4>POSIX Threads for Windows – REFERENCE - <A HREF="http://sources.redhat.com/pthreads-win32">Pthreads-w32</A></H4> +<P><A HREF="index.html">Reference Index</A></P> +<P><A HREF="#toc">Table of Contents</A></P> +<H2><A HREF="#toc0" NAME="sect0">Name</A></H2> +<P>pthread_attr_init, pthread_attr_destroy, +pthread_attr_setdetachstate, pthread_attr_getdetachstate, +pthread_attr_setschedparam, pthread_attr_getschedparam, +pthread_attr_setschedpolicy, pthread_attr_getschedpolicy, +pthread_attr_setinheritsched, pthread_attr_getinheritsched, +pthread_attr_setscope, pthread_attr_getscope - thread creation +attributes +</P> +<H2><A HREF="#toc1" NAME="sect1">Synopsis</A></H2> +<P><B>#include <pthread.h></B> +</P> +<P><B>int pthread_attr_init(pthread_attr_t *</B><I>attr</I><B>);</B> +</P> +<P><B>int pthread_attr_destroy(pthread_attr_t *</B><I>attr</I><B>);</B> +</P> +<P><B>int pthread_attr_setdetachstate(pthread_attr_t *</B><I>attr</I><B>, +int </B><I>detachstate</I><B>);</B> +</P> +<P><B>int pthread_attr_getdetachstate(const pthread_attr_t *</B><I>attr</I><B>, +int *</B><I>detachstate</I><B>);</B> +</P> +<P><B>int pthread_attr_setschedpolicy(pthread_attr_t *</B><I>attr</I><B>, +int </B><I>policy</I><B>);</B> +</P> +<P><B>int pthread_attr_getschedpolicy(const pthread_attr_t *</B><I>attr</I><B>, +int *</B><I>policy</I><B>);</B> +</P> +<P><B>int pthread_attr_setschedparam(pthread_attr_t *</B><I>attr</I><B>, +const struct sched_param *</B><I>param</I><B>);</B> +</P> +<P><B>int pthread_attr_getschedparam(const pthread_attr_t *</B><I>attr</I><B>, +struct sched_param *</B><I>param</I><B>);</B> +</P> +<P><B>int pthread_attr_setinheritsched(pthread_attr_t *</B><I>attr</I><B>, +int </B><I>inherit</I><B>);</B> +</P> +<P><B>int pthread_attr_getinheritsched(const pthread_attr_t *</B><I>attr</I><B>, +int *</B><I>inherit</I><B>);</B> +</P> +<P><B>int pthread_attr_setscope(pthread_attr_t *</B><I>attr</I><B>, +int </B><I>scope</I><B>);</B> +</P> +<P><B>int pthread_attr_getscope(const pthread_attr_t *</B><I>attr</I><B>, +int *</B><I>scope</I><B>);</B> +</P> +<H2><A HREF="#toc2" NAME="sect2">Description</A></H2> +<P>Setting attributes for threads is achieved by filling a thread +attribute object <I>attr</I> of type <B>pthread_attr_t</B>, then +passing it as second argument to <A HREF="pthread_create.html"><B>pthread_create</B>(3)</A> +. Passing <B>NULL</B> is equivalent to passing a thread attribute +object with all attributes set to their default values. +</P> +<P><B>pthread_attr_init</B> initializes the thread attribute object +<I>attr</I> and fills it with default values for the attributes. (The +default values are listed below for each attribute.) +</P> +<P>Each attribute <I>attrname</I> (see below for a list of all +attributes) can be individually set using the function +<B>pthread_attr_set</B><I>attrname</I> and retrieved using the +function <B>pthread_attr_get</B><I>attrname.</I> +</P> +<P><B>pthread_attr_destroy</B> destroys a thread attribute object, +which must not then be reused until it is reinitialized. +</P> +<P>Attribute objects are consulted only when creating a new thread. +The same attribute object can be used for creating several threads. +Modifying an attribute object after a call to <B>pthread_create</B> +does not change the attributes of the thread previously created. +</P> +<P>The following thread attributes are supported: +</P> +<H3><A HREF="#toc3" NAME="sect3">detachstate</A></H3> +<P>Control whether the thread is created in the joinable state (value +<B>PTHREAD_CREATE_JOINABLE</B>) or in the detached state ( +<B>PTHREAD_CREATE_DETACHED</B>). +</P> +<P>Default value: <B>PTHREAD_CREATE_JOINABLE</B>. +</P> +<P>In the joinable state, another thread can synchronize on the +thread termination and recover its termination code using +<A HREF="pthread_join.html"><B>pthread_join</B>(3)</A> . When a +joinable thread terminates, some of the thread resources are kept +allocated, and released only when another thread performs +<A HREF="pthread_join.html"><B>pthread_join</B>(3)</A> on that +thread. +</P> +<P>In the detached state, the thread's resources are released +immediately when it terminates. <A HREF="pthread_join.html"><B>pthread_join</B>(3)</A> +cannot be used to synchronize on the thread termination. +</P> +<P>A thread created in the joinable state can later be put in the +detached thread using <A HREF="pthread_detach.html"><B>pthread_detach</B>(3)</A> +. +</P> +<H3><A HREF="#toc4" NAME="sect4">schedpolicy</A></H3> +<P>Select the scheduling policy for the thread: one of <B>SCHED_OTHER</B> +(regular, non-real-time scheduling), <B>SCHED_RR</B> (real-time, +round-robin) or <B>SCHED_FIFO</B> (real-time, first-in first-out). +</P> +<P><B>Pthreads-w32</B> only supports <B>SCHED_OTHER</B> - attempting +to set one of the other policies will return an error ENOTSUP.</P> +<P>Default value: <B>SCHED_OTHER</B>. +</P> +<P><B>Pthreads-w32</B> only supports <B>SCHED_OTHER</B> - attempting +to set one of the other policies will return an error ENOTSUP.</P> +<P>The scheduling policy of a thread can be changed after creation +with <A HREF="pthread_setschedparam.html"><B>pthread_setschedparam</B>(3)</A> +. +</P> +<H3><A HREF="#toc5" NAME="sect5">schedparam</A></H3> +<P>Contain the scheduling parameters (essentially, the scheduling +priority) for the thread.</P> +<P><B>Pthreads-w32</B> supports the priority levels defined by the +Windows system it is running on. Under Windows, thread priorities are +relative to the process priority class, which must be set via the +Windows W32 API.</P> +<P>Default value: priority is 0 (Win32 level <B>THREAD_PRIORITY_NORMAL</B>). +</P> +<P>The scheduling priority of a thread can be changed after creation +with <A HREF="pthread_setschedparam.html"><B>pthread_setschedparam</B>(3)</A> +. +</P> +<H3><A HREF="#toc6" NAME="sect6">inheritsched</A></H3> +<P>Indicate whether the scheduling policy and scheduling parameters +for the newly created thread are determined by the values of the +<I>schedpolicy</I> and <I>schedparam</I> attributes (value +<B>PTHREAD_EXPLICIT_SCHED</B>) or are inherited from the parent +thread (value <B>PTHREAD_INHERIT_SCHED</B>). +</P> +<P>Default value: <B>PTHREAD_EXPLICIT_SCHED</B>. +</P> +<H3><A HREF="#toc7" NAME="sect7">scope</A></H3> +<P>Define the scheduling contention scope for the created thread. The +only value supported in the <B>Pthreads-w32</B> implementation is +<B>PTHREAD_SCOPE_SYSTEM</B>, meaning that the threads contend for CPU +time with all processes running on the machine. The other value +specified by the standard, <B>PTHREAD_SCOPE_PROCESS</B>, means that +scheduling contention occurs only between the threads of the running +process.</P> +<P><B>Pthreads-w32</B> only supports <B>PTHREAD_SCOPE_SYSTEM</B>.</P> +<P>Default value: <B>PTHREAD_SCOPE_SYSTEM</B>. +</P> +<H2><A HREF="#toc8" NAME="sect8">Return Value</A></H2> +<P>All functions return 0 on success and a non-zero error code on +error. On success, the <B>pthread_attr_get</B><I>attrname</I> +functions also store the current value of the attribute <I>attrname</I> +in the location pointed to by their second argument. +</P> +<H2><A HREF="#toc9" NAME="sect9">Errors</A></H2> +<P>The <B>pthread_attr_setdetachstate</B> function returns the +following error codes on error: +</P> +<DL> + <DL> + <DT STYLE="margin-right: 1cm; margin-bottom: 0.5cm"><B>EINVAL</B> + </DT><DD STYLE="margin-right: 1cm; margin-bottom: 0.5cm"> + the specified <I>detachstate</I> is not one of + <B>PTHREAD_CREATE_JOINABLE</B> or <B>PTHREAD_CREATE_DETACHED</B>. + </DD></DL> +</DL> +<P> +The <B>pthread_attr_setschedparam</B> function returns the following +error codes on error: +</P> +<DL> + <DL> + <DT STYLE="margin-right: 1cm; margin-bottom: 0.5cm"><B>EINVAL</B> + </DT><DD STYLE="margin-right: 1cm; margin-bottom: 0.5cm"> + the priority specified in <I>param</I> is outside the range of + allowed priorities for the scheduling policy currently in <I>attr</I> + (1 to 99 for <B>SCHED_FIFO</B> and <B>SCHED_RR</B>; 0 for + <B>SCHED_OTHER</B>). + </DD></DL> +</DL> +<P> +The <B>pthread_attr_setschedpolicy</B> function returns the following +error codes on error: +</P> +<DL> + <DL> + <DT STYLE="margin-right: 1cm; margin-bottom: 0.5cm"><B>EINVAL</B> + </DT><DD STYLE="margin-right: 1cm; margin-bottom: 0.5cm"> + the specified <I>policy</I> is not one of <B>SCHED_OTHER</B>, + <B>SCHED_FIFO</B>, or <B>SCHED_RR</B>. + </DD><DT STYLE="margin-right: 1cm; margin-bottom: 0.5cm"> + <B>ENOTSUP</B> + </DT><DD STYLE="margin-right: 1cm; margin-bottom: 0.5cm"> + <I>policy</I> is not <B>SCHED_OTHER</B>, the only value supported + by <B>Pthreads-w32</B>.</DD></DL> +</DL> +<P> +The <B>pthread_attr_setinheritsched</B> function returns the +following error codes on error: +</P> +<DL> + <DL> + <DT STYLE="margin-right: 1cm; margin-bottom: 0.5cm"><B>EINVAL</B> + </DT><DD STYLE="margin-right: 1cm; margin-bottom: 0.5cm"> + the specified <I>inherit</I> is not one of <B>PTHREAD_INHERIT_SCHED</B> + or <B>PTHREAD_EXPLICIT_SCHED</B>. + </DD></DL> +</DL> +<P> +The <B>pthread_attr_setscope</B> function returns the following error +codes on error: +</P> +<DL> + <DL> + <DT STYLE="margin-right: 1cm; margin-bottom: 0.5cm"><B>EINVAL</B> + </DT><DD STYLE="margin-right: 1cm; margin-bottom: 0.5cm"> + the specified <I>scope</I> is not one of <B>PTHREAD_SCOPE_SYSTEM</B> + or <B>PTHREAD_SCOPE_PROCESS</B>. + </DD><DT STYLE="margin-right: 1cm; margin-bottom: 0.5cm"> + <B>ENOTSUP</B> + </DT><DD STYLE="margin-right: 1cm; margin-bottom: 0.5cm"> + the specified <I>scope</I> is <B>PTHREAD_SCOPE_PROCESS</B> (not + supported by <B>Pthreads-w32</B>). + </DD></DL> +</DL> +<H2> +<A HREF="#toc10" NAME="sect10">Author</A></H2> +<P>Xavier Leroy <Xavier.Leroy@inria.fr> +</P> +<P>Modified by Ross Johnson for use with <A HREF="http://sources.redhat.com/pthreads-win32">Pthreads-w32</A>.</P> +<H2><A HREF="#toc11" NAME="sect11">See Also</A></H2> +<P><A HREF="pthread_create.html"><B>pthread_create</B>(3)</A> , +<A HREF="pthread_join.html"><B>pthread_join</B>(3)</A> , +<A HREF="pthread_detach.html"><B>pthread_detach</B>(3)</A> , +<A HREF="pthread_setschedparam.html"><B>pthread_setschedparam</B>(3)</A> +. +</P> +<HR> +<P><A NAME="toc"></A><B>Table of Contents</B></P> +<UL> + <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect0" NAME="toc0">Name</A> + </P> + <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect1" NAME="toc1">Synopsis</A> + </P> + <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect2" NAME="toc2">Description</A> + </P> + <UL> + <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect3" NAME="toc3">detachstate</A> + </P> + <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect4" NAME="toc4">schedpolicy</A> + </P> + <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect5" NAME="toc5">schedparam</A> + </P> + <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect6" NAME="toc6">inheritsched</A> + </P> + <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect7" NAME="toc7">scope</A> + </P> + </UL> + <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect8" NAME="toc8">Return + Value</A> + </P> + <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect9" NAME="toc9">Errors</A> + </P> + <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect10" NAME="toc10">Author</A> + </P> + <LI><P><A HREF="#sect11" NAME="toc11">See Also</A> + </P> +</UL> +</BODY> +</HTML> |