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<h3 class="section">12.4 Semaphores</h3>
<p>described here should be considered
experimental, subject to API changes without notice.
<p><a name="Structure-sb_002dthread_003asemaphore"></a>
<div class="defun">
— Structure: <b>sb-thread:semaphore</b><var><a name="index-sb_002dthread_003asemaphore-479"></a></var><br>
<blockquote><p><a name="index-sb_002dthread_003asemaphore-480"></a>Class precedence list: <code>semaphore, structure-object, t</code>
<p>Semaphore type. The fact that a <code>semaphore</code> is a <code>structure-object</code>
should be considered an implementation detail, and may change in the
future.
</p></blockquote></div>
<p><a name="Function-sb_002dthread_003amake_002dsemaphore"></a>
<div class="defun">
— Function: <b>sb-thread:make-semaphore</b><var> &key name count<a name="index-sb_002dthread_003amake_002dsemaphore-481"></a></var><br>
<blockquote><p><a name="index-sb_002dthread_003amake_002dsemaphore-482"></a>Create a semaphore with the supplied <code>count</code> and <code>name</code>.
</p></blockquote></div>
<p><a name="Function-sb_002dthread_003asemaphore_002dcount"></a>
<div class="defun">
— Function: <b>sb-thread:semaphore-count</b><var> instance<a name="index-sb_002dthread_003asemaphore_002dcount-483"></a></var><br>
<blockquote><p><a name="index-sb_002dthread_003asemaphore_002dcount-484"></a>Returns the current count of the semaphore <code>instance</code>.
</p></blockquote></div>
<p><a name="Function-sb_002dthread_003asemaphore_002dname"></a>
<div class="defun">
— Function: <b>sb-thread:semaphore-name</b><var> instance<a name="index-sb_002dthread_003asemaphore_002dname-485"></a></var><br>
<blockquote><p><a name="index-sb_002dthread_003asemaphore_002dname-486"></a>Name of a <code>queue</code>. Can be assingned to using <code>setf</code>. Queue names
can be arbitrary printable objects, and need not be unique.
</p></blockquote></div>
<p><a name="Function-sb_002dthread_003asignal_002dsemaphore"></a>
<div class="defun">
— Function: <b>sb-thread:signal-semaphore</b><var> semaphore &optional n<a name="index-sb_002dthread_003asignal_002dsemaphore-487"></a></var><br>
<blockquote><p><a name="index-sb_002dthread_003asignal_002dsemaphore-488"></a>Increment the count of <code>semaphore</code> by <code>n</code>. If there are threads waiting
on this semaphore, then <code>n</code> of them is woken up.
</p></blockquote></div>
<p><a name="Function-sb_002dthread_003await_002don_002dsemaphore"></a>
<div class="defun">
— Function: <b>sb-thread:wait-on-semaphore</b><var> semaphore<a name="index-sb_002dthread_003await_002don_002dsemaphore-489"></a></var><br>
<blockquote><p><a name="index-sb_002dthread_003await_002don_002dsemaphore-490"></a>Decrement the count of <code>semaphore</code> if the count would not be
negative. Else blocks until the semaphore can be decremented.
</p></blockquote></div>
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distrib
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Mandriva
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2010.0
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i586
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media
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contrib-release
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by-pkgid
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723830890bac44da3d113209b14e090b
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files
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593
