1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>wait_event_freezable</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="Linux Device Drivers"><link rel="up" href="ch01s04.html" title="Wait queues and Wake events"><link rel="prev" href="API-wait-event.html" title="wait_event"><link rel="next" href="API-wait-event-timeout.html" title="wait_event_timeout"></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">wait_event_freezable</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-wait-event.html">Prev</a>&#160;</td><th width="60%" align="center">Wait queues and Wake events</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-wait-event-timeout.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-wait-event-freezable"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>wait_event_freezable &#8212; 
2     sleep (or freeze) until a condition gets true
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"> <b class="fsfunc">wait_event_freezable </b>(</code></td><td> <var class="pdparam">wq</var>, </td></tr><tr><td>&#160;</td><td> <var class="pdparam">condition</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1107128028"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>wq</code></em></span></dt><dd><p>
4     the waitqueue to wait on
5    </p></dd><dt><span class="term"><em class="parameter"><code>condition</code></em></span></dt><dd><p>
6     a C expression for the event to wait for
7    </p></dd></dl></div></div><div class="refsect1"><a name="idp1107130604"></a><h2>Description</h2><p>
8   The process is put to sleep (TASK_INTERRUPTIBLE -- so as not to contribute
9   to system load) until the <em class="parameter"><code>condition</code></em> evaluates to true. The
10   <em class="parameter"><code>condition</code></em> is checked each time the waitqueue <em class="parameter"><code>wq</code></em> is woken up.
11   </p><p>
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13   <code class="function">wake_up</code> has to be called after changing any variable that could
14   change the result of the wait condition.
15</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="API-wait-event.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="ch01s04.html">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-wait-event-timeout.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">wait_event</span>&#160;</td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top">&#160;<span class="phrase">wait_event_timeout</span></td></tr></table></div></body></html>
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