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<h1>Module <a href="type_Condition.html">Condition</a></h1>
<pre><span id="MODULECondition"><span class="keyword">module</span> Condition</span>: <code class="code"><span class="keyword">sig</span></code> <a href="Condition.html">..</a> <code class="code"><span class="keyword">end</span></code></pre><div class="info module top">
<div class="info-desc">
<p>Condition variables to synchronize between threads.</p>
<p>Condition variables are used when one thread wants to wait until another
thread has finished doing something: the former thread 'waits' on the
condition variable, the latter thread 'signals' the condition when it
is done. Condition variables should always be protected by a mutex.
The typical use is (if <code class="code"><span class="constructor">D</span></code> is a shared data structure, <code class="code">m</code> its mutex,
and <code class="code">c</code> is a condition variable):</p>
<pre class="codepre"><code class="code"> <span class="constructor">Mutex</span>.lock m;
<span class="keyword">while</span> <span class="comment">(* some predicate P over D is not satisfied *)</span> <span class="keyword">do</span>
<span class="constructor">Condition</span>.wait c m
<span class="keyword">done</span>;
<span class="comment">(* Modify D *)</span>
<span class="keyword">if</span> <span class="comment">(* the predicate P over D is now satisfied *)</span> <span class="keyword">then</span> <span class="constructor">Condition</span>.signal c;
<span class="constructor">Mutex</span>.unlock m
</code></pre></div>
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<pre><span id="TYPEt"><span class="keyword">type</span> <code class="type"></code>t</span> </pre>
<div class="info ">
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<p>The type of condition variables.</p>
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<pre><span id="VALcreate"><span class="keyword">val</span> create</span> : <code class="type">unit -> <a href="Condition.html#TYPEt">t</a></code></pre><div class="info ">
<div class="info-desc">
<p>Return a new condition variable.</p>
</div>
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<pre><span id="VALwait"><span class="keyword">val</span> wait</span> : <code class="type"><a href="Condition.html#TYPEt">t</a> -> <a href="Mutex.html#TYPEt">Mutex.t</a> -> unit</code></pre><div class="info ">
<div class="info-desc">
<p><code class="code">wait c m</code> atomically unlocks the mutex <code class="code">m</code> and suspends the
calling process on the condition variable <code class="code">c</code>. The process will
restart after the condition variable <code class="code">c</code> has been signalled.
The mutex <code class="code">m</code> is locked again before <code class="code">wait</code> returns.</p>
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<pre><span id="VALsignal"><span class="keyword">val</span> signal</span> : <code class="type"><a href="Condition.html#TYPEt">t</a> -> unit</code></pre><div class="info ">
<div class="info-desc">
<p><code class="code">signal c</code> restarts one of the processes waiting on the
condition variable <code class="code">c</code>.</p>
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<pre><span id="VALbroadcast"><span class="keyword">val</span> broadcast</span> : <code class="type"><a href="Condition.html#TYPEt">t</a> -> unit</code></pre><div class="info ">
<div class="info-desc">
<p><code class="code">broadcast c</code> restarts all processes waiting on the
condition variable <code class="code">c</code>.</p>
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