<!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_MUTEXATTR_GETPSHARED"(P) manual page</TITLE> <META NAME="GENERATOR" CONTENT="OpenOffice.org 1.1.3 (Linux)"> <META NAME="CREATED" CONTENT="20050504;23480600"> <META NAME="CHANGED" CONTENT="20050505;18381800"> <!-- 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_mutexattr_getpshared, pthread_mutexattr_setpshared - get and set the process-shared attribute </P> <H2><A HREF="#toc1" NAME="sect1">Synopsis</A></H2> <P><B>#include <pthread.h> </B> </P> <P><B>int pthread_mutexattr_getpshared(const pthread_mutexattr_t * restrict</B> <I>attr</I><B>, int *restrict</B> <I>pshared</I><B>); <BR>int pthread_mutexattr_setpshared(pthread_mutexattr_t *</B><I>attr</I><B>, int</B> <I>pshared</I><B>); </B> </P> <H2><A HREF="#toc2" NAME="sect2">Description</A></H2> <P>The <B>pthread_mutexattr_getpshared</B> function shall obtain the value of the <I>process-shared</I> attribute from the attributes object referenced by <I>attr</I>. The <B>pthread_mutexattr_setpshared</B> function shall set the <I>process-shared</I> attribute in an initialized attributes object referenced by <I>attr</I>. </P> <P>The <I>process-shared</I> attribute is set to <B>PTHREAD_PROCESS_SHARED</B> to permit a mutex to be operated upon by any thread that has access to the memory where the mutex is allocated, even if the mutex is allocated in memory that is shared by multiple processes. If the <I>process-shared</I> attribute is <B>PTHREAD_PROCESS_PRIVATE</B>, the mutex shall only be operated upon by threads created within the same process as the thread that initialized the mutex; if threads of differing processes attempt to operate on such a mutex, the behavior is undefined. The default value of the attribute shall be <B>PTHREAD_PROCESS_PRIVATE</B>. </P> <P><B>Pthreads-w32</B> defines <B>_POSIX_THREAD_PROCESS_SHARED</B> in pthread.h as -1 to indicate that these routines are implemented but the process shared option is not supported.</P> <H2><A HREF="#toc3" NAME="sect3">Return Value</A></H2> <P>Upon successful completion, <B>pthread_mutexattr_setpshared</B> shall return zero; otherwise, an error number shall be returned to indicate the error. </P> <P>Upon successful completion, <B>pthread_mutexattr_getpshared</B> shall return zero and store the value of the <I>process-shared</I> attribute of <I>attr</I> into the object referenced by the <I>pshared</I> parameter. Otherwise, an error number shall be returned to indicate the error. </P> <H2><A HREF="#toc4" NAME="sect4">Errors</A></H2> <P>The <B>pthread_mutexattr_getpshared</B> and <B>pthread_mutexattr_setpshared</B> functions may fail if: </P> <DL> <DT><B>EINVAL</B> </DT><DD STYLE="margin-bottom: 0.5cm"> The value specified by <I>attr</I> is invalid. </DD></DL> <P> The <B>pthread_mutexattr_setpshared</B> function may fail if: </P> <DL> <DT><B>EINVAL</B> </DT><DD STYLE="margin-bottom: 0.5cm"> The new value specified for the attribute is outside the range of legal values for that attribute. </DD><DT> <B>ENOTSUP</B> </DT><DD STYLE="margin-bottom: 0.5cm"> The new value specified for the attribute is PTHREAD_PROCESS_SHARED. </DD></DL> <P> These functions shall not return an error code of [EINTR]. </P> <P><I>The following sections are informative.</I> </P> <H2><A HREF="#toc5" NAME="sect5">Examples</A></H2> <P>None. </P> <H2><A HREF="#toc6" NAME="sect6">Application Usage</A></H2> <P>None. </P> <H2><A HREF="#toc7" NAME="sect7">Rationale</A></H2> <P>None. </P> <H2><A HREF="#toc8" NAME="sect8">Future Directions</A></H2> <P>None. </P> <H2><A HREF="#toc9" NAME="sect9">See Also</A></H2> <P><A HREF="pthread_cond_init.html"><B>pthread_cond_destroy</B>(3)</A> <B>,</B> <A HREF="pthread_create.html"><B>pthread_create</B>(3)</A> <B>,</B> <A HREF="pthread_mutex_init.html"><B>pthread_mutex_destroy</B>(3)</A> <B>,</B> <A HREF="pthread_mutexattr_init.html"><B>pthread_mutexattr_destroy</B>(3)</A> <B>,</B> the Base Definitions volume of IEEE Std 1003.1-2001, <I><pthread.h></I> </P> <H2><A HREF="#toc10" NAME="sect10">Copyright</A></H2> <P>Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at <A HREF="http://www.opengroup.org/unix/online.html">http://www.opengroup.org/unix/online.html</A> . </P> <P>Modified by Ross Johnson for use with <A HREF="http://sources.redhat.com/pthreads-win32">Pthreads-w32</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> <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect3" NAME="toc3">Return Value</A> </P> <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect4" NAME="toc4">Errors</A> </P> <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect5" NAME="toc5">Examples</A> </P> <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect6" NAME="toc6">Application Usage</A> </P> <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect7" NAME="toc7">Rationale</A> </P> <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect8" NAME="toc8">Future Directions</A> </P> <LI><P STYLE="margin-bottom: 0cm"><A HREF="#sect9" NAME="toc9">See Also</A> </P> <LI><P><A HREF="#sect10" NAME="toc10">Copyright</A> </P> </UL> </BODY> </HTML>