1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>atomic_dec_and_mutex_lock</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="Unreliable Guide To Locking"><link rel="up" href="apiref-mutex.html" title="Chapter&#160;11.&#160;Mutex API reference"><link rel="prev" href="API-mutex-trylock.html" title="mutex_trylock"><link rel="next" href="apiref-futex.html" title="Chapter&#160;12.&#160;Futex API reference"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span class="phrase">atomic_dec_and_mutex_lock</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-mutex-trylock.html">Prev</a>&#160;</td><th width="60%" align="center">Chapter&#160;11.&#160;Mutex API reference</th><td width="20%" align="right">&#160;<a accesskey="n" href="apiref-futex.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-atomic-dec-and-mutex-lock"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>atomic_dec_and_mutex_lock &#8212; 
2     return holding mutex if we dec to 0
3 </p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">atomic_dec_and_mutex_lock </b>(</code></td><td>atomic_t * <var class="pdparam">cnt</var>, </td></tr><tr><td>&#160;</td><td>struct mutex * <var class="pdparam">lock</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1124770300"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>cnt</code></em></span></dt><dd><p>
4     the atomic which we are to dec
5    </p></dd><dt><span class="term"><em class="parameter"><code>lock</code></em></span></dt><dd><p>
6     the mutex to return holding if we dec to 0
7    </p></dd></dl></div></div><div class="refsect1"><a name="idp1124772892"></a><h2>Description</h2><p>
8   return true and hold lock if we dec to 0, return false otherwise
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