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<title>pthread_rwlock_destroy()--Destroy Read/Write Lock</title>
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<h2>pthread_rwlock_destroy()--Destroy Read/Write Lock</h2>
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&nbsp;&nbsp;Syntax:
<pre> #include &lt;pthread.h&gt;
int pthread_rwlock_destroy(pthread_rwlock_t *rwlock); </pre>
&nbsp;&nbsp;Service Program Name: QP0WPTHR<br>
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&nbsp;&nbsp;Default Public Authority: *USE <br>
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&nbsp;&nbsp;Threadsafe: Yes<br>
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&nbsp;&nbsp;Signal Safe: Yes<br>
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<p>The <strong>pthread_rwlock_destroy</strong>() function destroys the named read/write lock. The destroyed read/write lock can no longer be used.</p>
<p>If <strong>pthread_rwlock_destroy</strong>() is called on a read/write lock on a mutex that is locked by another thread for either reading or writing, the request fails with an <strong>EBUSY</strong> error.</p>
<p>If <strong>pthread_rwlock_destroy</strong>() is used by a thread when it owns the read/write lock, and other threads are waiting for the read/write lock to become available (with calls to <strong>pthread_rwlock_rdlock</strong>(), <strong>pthread_rwlock_wrlock</strong>(), <strong>pthread_rwlock_timedrdlock_np</strong>() or <strong>pthread_rwlock_timedwrlock_np</strong>() APIs), the read/write lock is destroyed safely, and the waiting threads wake up with the <strong>EDESTROYED</strong> error. Threads calling <strong>pthread_rwlock_tryrdlock</strong>() or <strong>pthread_rwlock_trywrlock</strong>() return with either the <strong>EBUSY</strong> or <strong>EINVAL</strong> error, depending on when they called those functions.</p>
<p>Once a read/write lock is created, it cannot be validly copied or moved to a new location.</p>
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<h3>Authorities and Locks</h3>
<p>None.</p>
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<h3>Parameters</h3>
<dl>
<dt><strong>rwlock</strong></dt>
<dd>(Input) Address of the read/write lock to be destroyed</dd>
</dl>
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<h3>Return Value</h3>
<dl>
<dt><strong>0</strong></dt>
<dd><strong>pthread_rwlock_destroy</strong>() was successful.</dd>
<dt><strong>value</strong></dt>
<dd><strong>pthread_rwlock_destroy</strong>() was not successful. <em>value</em> is set to indicate the error condition.</dd>
</dl>
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<h3>Error Conditions</h3>
<p>If <strong>pthread_rwlock_destroy</strong>() was not successful, the error condition returned usually indicates one of the following errors. Under some conditions, the value returned could indicate an error other than those listed here.</p>
<dl>
<dt><em>[EINVAL]</em></dt>
<dd><p>The value specified for the argument is not correct.</p></dd>
</dl>
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<h3>Related Information</h3>
<ul>
<li>The &lt;<strong>pthread.h</strong>> header file. See <a href="rzah4hed.htm">Header files for Pthread functions</a>.<br><br></li>
<li><a href="users_86.htm">pthread_rwlock_init()</a>--Initialize Read/Write Lock</li>
</ul>
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<h3>Example</h3>
<p>See <a href="../apiref/aboutapis.htm#codedisclaimer">Code disclaimer information</a>
for information pertaining to code examples.</p>
<p>See the <a href="users_86.htm#372485"><strong>pthread_rwlock_init</strong>() example</a>.</p>
<hr>
API introduced: V4R3
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