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diff --git a/pthreads/manual/pthread_spin_lock.html b/pthreads/manual/pthread_spin_lock.html new file mode 100644 index 000000000..dd180ae6a --- /dev/null +++ b/pthreads/manual/pthread_spin_lock.html @@ -0,0 +1,141 @@ +<!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_SPIN_LOCK"(P) manual page</TITLE> + <META NAME="GENERATOR" CONTENT="OpenOffice.org 1.1.3 (Linux)"> + <META NAME="CREATED" CONTENT="20050505;12202300"> + <META NAME="CHANGED" CONTENT="20050505;19302300"> + <!-- 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_spin_lock, pthread_spin_trylock - lock a spin lock object +(<B>ADVANCED REALTIME THREADS</B>) +</P> +<H2><A HREF="#toc1" NAME="sect1">Synopsis</A></H2> +<P><B>#include <pthread.h> </B> +</P> +<P><B>int pthread_spin_lock(pthread_spinlock_t *</B><I>lock</I><B>); +<BR>int pthread_spin_trylock(pthread_spinlock_t *</B><I>lock</I><B>); +</B> +</P> +<H2><A HREF="#toc2" NAME="sect2">Description</A></H2> +<P>The <B>pthread_spin_lock</B> function shall lock the spin lock +referenced by <I>lock</I>. The calling thread shall acquire the lock +if it is not held by another thread. Otherwise, the thread shall spin +(that is, shall not return from the <B>pthread_spin_lock</B> call) +until the lock becomes available. The results are undefined if the +calling thread holds the lock at the time the call is made.</P> +<P><B>Pthreads-w32</B> supports single and multiple processor systems +as well as process CPU affinity masking by checking the mask when the +spin lock is initialized. If the process is using only a single +processor at the time <A HREF="pthread_spin_init.html"><B>pthread_spin_init</B>(3)</A> +is called then the spin lock is initialized as a PTHREAD_MUTEX_NORMAL +mutex object. A thread that calls <B>pthread_spin_lock</B> will block +rather than spin in this case. If the process CPU affinity mask is +altered after the spin lock has been initialised, the spin lock is +not modified, and may no longer be optimal for the number of CPUs +available.</P> +<P>The <B>pthread_spin_trylock</B> function shall lock the spin lock +referenced by <I>lock</I> if it is not held by any thread. Otherwise, +the function shall fail. +</P> +<P>The results are undefined if any of these functions is called with +an uninitialized spin lock. +</P> +<H2><A HREF="#toc3" NAME="sect3">Return Value</A></H2> +<P>Upon successful completion, these 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>These functions may fail if: +</P> +<DL> + <DT><B>EINVAL</B> + </DT><DD STYLE="margin-bottom: 0.5cm"> + The value specified by <I>lock</I> does not refer to an initialized + spin lock object. + </DD></DL> +<P> +The <B>pthread_spin_trylock</B> function shall fail if: +</P> +<DL> + <DT><B>EBUSY</B> + </DT><DD STYLE="margin-bottom: 0.5cm"> + A thread currently holds the lock. + </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>Applications using this function may be subject to priority +inversion, as discussed in the Base Definitions volume of +IEEE Std 1003.1-2001, Section 3.285, Priority Inversion. +</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_spin_init.html"><B>pthread_spin_destroy</B>(3)</A> +<B>,</B> <A HREF="pthread_spin_unlock.html"><B>pthread_spin_unlock</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> |