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<li ><a href="#method-c-new">::new</a>
<li ><a href="#method-i-broadcast">#broadcast</a>
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<li ><a href="#method-i-wait">#wait</a>
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<h1 id="class-ConditionVariable" class="class">
class ConditionVariable
</h1>
<section class="description">
<p><a href="ConditionVariable.html"><code>ConditionVariable</code></a> objects augment class <a href="Mutex.html"><code>Mutex</code></a>. Using condition variables, it is possible to suspend while in the middle of a critical section until a resource becomes available.</p>
<p>Example:</p>
<pre class="ruby"><span class="ruby-identifier">mutex</span> = <span class="ruby-constant">Mutex</span>.<span class="ruby-identifier">new</span>
<span class="ruby-identifier">resource</span> = <span class="ruby-constant">ConditionVariable</span>.<span class="ruby-identifier">new</span>
<span class="ruby-identifier">a</span> = <span class="ruby-constant">Thread</span>.<span class="ruby-identifier">new</span> {
<span class="ruby-identifier">mutex</span>.<span class="ruby-identifier">synchronize</span> {
<span class="ruby-comment"># Thread 'a' now needs the resource</span>
<span class="ruby-identifier">resource</span>.<span class="ruby-identifier">wait</span>(<span class="ruby-identifier">mutex</span>)
<span class="ruby-comment"># 'a' can now have the resource</span>
}
}
<span class="ruby-identifier">b</span> = <span class="ruby-constant">Thread</span>.<span class="ruby-identifier">new</span> {
<span class="ruby-identifier">mutex</span>.<span class="ruby-identifier">synchronize</span> {
<span class="ruby-comment"># Thread 'b' has finished using the resource</span>
<span class="ruby-identifier">resource</span>.<span class="ruby-identifier">signal</span>
}
}
</pre>
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<h3>Public Class Methods</h3>
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<div id="method-c-new" class="method-detail ">
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<span class="method-name">new</span><span
class="method-args">()</span>
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<p>Creates a new condition variable instance.</p>
<div class="method-source-code" id="new-source">
<pre>static VALUE
rb_condvar_initialize(VALUE self)
{
struct rb_condvar *cv = condvar_ptr(self);
list_head_init(&cv->waitq);
return self;
}</pre>
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<h3>Public Instance Methods</h3>
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<div id="method-i-broadcast" class="method-detail ">
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<span class="method-name">broadcast</span><span
class="method-args">()</span>
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<p>Wakes up all threads waiting for this lock.</p>
<div class="method-source-code" id="broadcast-source">
<pre>static VALUE
rb_condvar_broadcast(VALUE self)
{
struct rb_condvar *cv = condvar_ptr(self);
wakeup_all(&cv->waitq);
return self;
}</pre>
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<span class="method-name">signal</span><span
class="method-args">()</span>
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<p>Wakes up the first thread in line waiting for this lock.</p>
<div class="method-source-code" id="signal-source">
<pre>static VALUE
rb_condvar_signal(VALUE self)
{
struct rb_condvar *cv = condvar_ptr(self);
wakeup_one(&cv->waitq);
return self;
}</pre>
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<div id="method-i-wait" class="method-detail ">
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<span class="method-callseq">
wait(mutex, timeout=nil)
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<div class="method-description">
<p>Releases the lock held in <code>mutex</code> and waits; reacquires the lock on wakeup.</p>
<p>If <code>timeout</code> is given, this method returns after <code>timeout</code> seconds passed, even if no other thread doesn't signal.</p>
<div class="method-source-code" id="wait-source">
<pre>static VALUE
rb_condvar_wait(int argc, VALUE *argv, VALUE self)
{
struct rb_condvar *cv = condvar_ptr(self);
struct sleep_call args;
struct sync_waiter w;
rb_scan_args(argc, argv, "11", &args.mutex, &args.timeout);
w.th = GET_THREAD();
list_add_tail(&cv->waitq, &w.node);
rb_ensure(do_sleep, (VALUE)&args, delete_from_waitq, (VALUE)&w);
return self;
}</pre>
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