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<TITLE>C API Reference -- Ns_WaitForSemaphore</TITLE>
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<a name="214172">
</a><h3>Ns_WaitForSemaphore</h3>
<a name="133581">
</a><h4>Overview</h4>
Wait for a semaphore count to be greater than zero.
<a name="133582">
</a><a name="133583">
</a><h4>Syntax</h4>
<pre> <a name="69900"></a>int Ns_WaitForSemaphore(
<a name="69901"></a>Ns_Semaphore * sema
<a name="69902"></a>);
</pre><p><a name="134955">
</a><h4>Description</h4>
<p><a name="214115">
</a>If the semaphore count is greater than zero, decrement it and continue. Otherwise, block until this is possible.</p>
<p><a name="781284">
</a>Ns_SemaWait is the preferred function for waiting for a semaphore.</p>
<a name="214116">
</a><h4>Examples</h4>
<pre> <a name="214124"></a>static Ns_Semaphore sem;
<a name="214126"></a>
<a name="214127"></a>void<br>
Init(void)
<a name="214128"></a>{
<a name="214129"></a> Ns_InitializeSemaphore(&sem, 0);
<a name="214130"></a>}
<a name="214131"></a>
<a name="214132"></a>void
<a name="214149"></a>Waiter(void)
<a name="214150"></a>{
<a name="214151"></a> Ns_WaitForSemaphore(&sem);
<a name="214136"></a> ... access resource ...
<a name="214137"></a>}
<a name="214138"></a>
<a name="214139"></a>void
<a name="214140"></a>Releaser(void)
<a name="214141"></a>{
<a name="214142"></a> Ns_ReleaseSemaphore(&sem, 1);
<a name="214143"></a>}
<a name="214144"></a>
</pre><p>
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