<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
	<META HTTP-EQUIV="CONTENT-TYPE" CONTENT="text/html; charset=utf-8">
	<TITLE>&quot;PTHREAD_RWLOCKATTR_DESTROY&quot;(P) manual page</TITLE>
	<META NAME="GENERATOR" CONTENT="OpenOffice.org 1.1.3  (Linux)">
	<META NAME="CREATED" CONTENT="20050505;504000">
	<META NAME="CHANGED" CONTENT="20050505;18474200">
	<!-- 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_rwlockattr_destroy, pthread_rwlockattr_init - destroy and
initialize the read-write lock attributes object 
</P>
<H2><A HREF="#toc1" NAME="sect1">Synopsis</A></H2>
<P><B>#include &lt;pthread.h&gt; </B>
</P>
<P><B>int pthread_rwlockattr_destroy(pthread_rwlockattr_t <I>*</I></B><I>attr</I><B>);
<BR>int pthread_rwlockattr_init(pthread_rwlockattr_t <I>*</I></B><I>attr</I><B>);
</B>
</P>
<H2><A HREF="#toc2" NAME="sect2">Description</A></H2>
<P>The <B>pthread_rwlockattr_destroy</B> function shall destroy a
read-write lock attributes object. A destroyed <I>attr</I> attributes
object can be reinitialized using <B>pthread_rwlockattr_init</B> ;
the results of otherwise referencing the object after it has been
destroyed are undefined. An implementation may cause
<B>pthread_rwlockattr_destroy</B> to set the object referenced by
<I>attr</I> to an invalid value. 
</P>
<P>The <B>pthread_rwlockattr_init</B> function shall initialize a
read-write lock attributes object <I>attr</I> with the default value
for all of the attributes defined by the implementation. 
</P>
<P>Results are undefined if <B>pthread_rwlockattr_init</B> is called
specifying an already initialized <I>attr</I> attributes object. 
</P>
<P>After a read-write lock attributes object has been used to
initialize one or more read-write locks, any function affecting the
attributes object (including destruction) shall not affect any
previously initialized read-write locks. 
</P>
<P><B>Pthreads-w32</B> defines <B>_POSIX_READER_WRITER_LOCKS</B> in
pthread.h as 200112L to indicate that the reader/writer routines are
implemented and may be used.</P>
<H2><A HREF="#toc3" NAME="sect3">Return Value</A></H2>
<P>If successful, the <B>pthread_rwlockattr_destroy</B> and
<B>pthread_rwlockattr_init</B> functions shall return zero;
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_rwlockattr_destroy</B> function 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_rwlockattr_init</B> function shall fail if: 
</P>
<DL>
	<DT><B>ENOMEM</B> 
	</DT><DD STYLE="margin-bottom: 0.5cm">
	Insufficient memory exists to initialize the read-write lock
	attributes object. 
	</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_rwlock_init.html"><B>pthread_rwlock_destroy</B>(3)</A>
<B>,</B> <A HREF="pthread_rwlockattr_setpshared.html"><B>pthread_rwlockattr_getpshared</B>(3)</A>
<B>,</B> <A HREF="pthread_rwlockattr_setpshared.html"><B>pthread_rwlockattr_setpshared</B>(3)</A>
<B>,</B> the Base Definitions volume of IEEE&nbsp;Std&nbsp;1003.1-2001,
<I>&lt;pthread.h&gt;</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>