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<a href="#typedef-members">Typedefs</a> |
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<div class="title">Condition Variable Routines<div class="ingroups"><a class="el" href="group___a_p_r.html">Apache Portability Runtime library</a></div></div> </div>
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Typedefs</h2></td></tr>
<tr class="memitem:gae8f918d38bf1c58bc09670eee456ae5e"><td class="memItemLeft" align="right" valign="top">typedef struct <a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a></td></tr>
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Functions</h2></td></tr>
<tr class="memitem:gab39e8b722d46d23466e9e346ada85a7f"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__apr__thread__cond.html#gab39e8b722d46d23466e9e346ada85a7f">apr_thread_cond_create</a> (<a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> **cond, <a class="el" href="group__apr__pools.html#gaf137f28edcf9a086cd6bc36c20d7cdfb">apr_pool_t</a> *pool)</td></tr>
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<tr class="memitem:ga789719a5f02bdab8b8abbc8bddd0406b"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__apr__thread__cond.html#ga789719a5f02bdab8b8abbc8bddd0406b">apr_thread_cond_wait</a> (<a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> *cond, <a class="el" href="group__apr__thread__mutex.html#ga95712060ba3a192036416e1ccef1db75">apr_thread_mutex_t</a> *mutex)</td></tr>
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<tr class="memitem:gadf7ad6c2731bc6128f969d3efc7ff5eb"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__apr__thread__cond.html#gadf7ad6c2731bc6128f969d3efc7ff5eb">apr_thread_cond_signal</a> (<a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> *cond)</td></tr>
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<tr class="memitem:gafbbedd2a07629fe3186343035ae83152"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__apr__thread__cond.html#gafbbedd2a07629fe3186343035ae83152">apr_thread_cond_broadcast</a> (<a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> *cond)</td></tr>
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<tr class="memitem:gafc2d7f2907eb12e5543c971a4c0140ee"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__apr__pools.html#gaf137f28edcf9a086cd6bc36c20d7cdfb">apr_pool_t</a> * </td><td class="memItemRight" valign="bottom"><a class="el" href="group__apr__thread__cond.html#gafc2d7f2907eb12e5543c971a4c0140ee">apr_thread_cond_pool_get</a> (const <a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> *thethread_cond)</td></tr>
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<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<h2 class="groupheader">Typedef Documentation</h2>
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<h2 class="memtitle"><span class="permalink"><a href="#gae8f918d38bf1c58bc09670eee456ae5e">◆ </a></span>apr_thread_cond_t</h2>
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<td class="memname">typedef struct <a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> <a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a></td>
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<p>Opaque structure for thread condition variables </p>
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<h2 class="groupheader">Function Documentation</h2>
<a id="gafbbedd2a07629fe3186343035ae83152"></a>
<h2 class="memtitle"><span class="permalink"><a href="#gafbbedd2a07629fe3186343035ae83152">◆ </a></span>apr_thread_cond_broadcast()</h2>
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<td class="memname"><a class="el" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a> apr_thread_cond_broadcast </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> * </td>
<td class="paramname"><em>cond</em></td><td>)</td>
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<p>Signals all threads blocking on the given condition variable. Each thread that was signaled is then scheduled to wake up and acquire the associated mutex. This will happen in a serialized manner. </p><dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">cond</td><td>the condition variable on which to produce the broadcast. </td></tr>
</table>
</dd>
</dl>
<dl class="section remark"><dt>Remarks</dt><dd>If no threads are waiting on the condition variable, nothing happens. </dd></dl>
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<h2 class="memtitle"><span class="permalink"><a href="#gab39e8b722d46d23466e9e346ada85a7f">◆ </a></span>apr_thread_cond_create()</h2>
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<td class="memname"><a class="el" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a> apr_thread_cond_create </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> ** </td>
<td class="paramname"><em>cond</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group__apr__pools.html#gaf137f28edcf9a086cd6bc36c20d7cdfb">apr_pool_t</a> * </td>
<td class="paramname"><em>pool</em> </td>
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<p>Note: destroying a condition variable (or likewise, destroying or clearing the pool from which a condition variable was allocated) if any threads are blocked waiting on it gives undefined results. Create and initialize a condition variable that can be used to signal and schedule threads in a single process. </p><dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">cond</td><td>the memory address where the newly created condition variable will be stored. </td></tr>
<tr><td class="paramname">pool</td><td>the pool from which to allocate the condition. </td></tr>
</table>
</dd>
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<a id="ga049e646e23c670f3a79fe25401b9c1b0"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ga049e646e23c670f3a79fe25401b9c1b0">◆ </a></span>apr_thread_cond_destroy()</h2>
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<td class="memname"><a class="el" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a> apr_thread_cond_destroy </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> * </td>
<td class="paramname"><em>cond</em></td><td>)</td>
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<p>Destroy the condition variable and free the associated memory. </p><dl class="params"><dt>Parameters</dt><dd>
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<tr><td class="paramname">cond</td><td>the condition variable to destroy. </td></tr>
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</dd>
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<h2 class="memtitle"><span class="permalink"><a href="#gafc2d7f2907eb12e5543c971a4c0140ee">◆ </a></span>apr_thread_cond_pool_get()</h2>
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<td class="memname"><a class="el" href="group__apr__pools.html#gaf137f28edcf9a086cd6bc36c20d7cdfb">apr_pool_t</a>* apr_thread_cond_pool_get </td>
<td>(</td>
<td class="paramtype">const <a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> * </td>
<td class="paramname"><em>thethread_cond</em></td><td>)</td>
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<p>Get the pool used by this thread_cond. </p><dl class="section return"><dt>Returns</dt><dd>apr_pool_t the pool </dd></dl>
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<h2 class="memtitle"><span class="permalink"><a href="#gadf7ad6c2731bc6128f969d3efc7ff5eb">◆ </a></span>apr_thread_cond_signal()</h2>
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<td class="memname"><a class="el" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a> apr_thread_cond_signal </td>
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<td class="paramtype"><a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> * </td>
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<p>Signals a single thread, if one exists, that is blocking on the given condition variable. That thread is then scheduled to wake up and acquire the associated mutex. Although it is not required, if predictable scheduling is desired, that mutex must be locked while calling this function. </p><dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">cond</td><td>the condition variable on which to produce the signal. </td></tr>
</table>
</dd>
</dl>
<dl class="section remark"><dt>Remarks</dt><dd>If no threads are waiting on the condition variable, nothing happens. </dd></dl>
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<h2 class="memtitle"><span class="permalink"><a href="#ga67f2feecb7fa1929cc9b354dafd00306">◆ </a></span>apr_thread_cond_timedwait()</h2>
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<td class="memname"><a class="el" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a> apr_thread_cond_timedwait </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> * </td>
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<td class="paramkey"></td>
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<td class="paramtype"><a class="el" href="group__apr__thread__mutex.html#ga95712060ba3a192036416e1ccef1db75">apr_thread_mutex_t</a> * </td>
<td class="paramname"><em>mutex</em>, </td>
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<td class="paramtype"><a class="el" href="group__apr__time.html#gaae2129185a395cc393f76fabf4f43e47">apr_interval_time_t</a> </td>
<td class="paramname"><em>timeout</em> </td>
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<p>Put the active calling thread to sleep until signaled to wake up or the timeout is reached. Each condition variable must be associated with a mutex, and that mutex must be locked before calling this function, or the behavior will be undefined. As the calling thread is put to sleep, the given mutex will be simultaneously released; and as this thread wakes up the lock is again simultaneously acquired. </p><dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">cond</td><td>the condition variable on which to block. </td></tr>
<tr><td class="paramname">mutex</td><td>the mutex that must be locked upon entering this function, is released while the thread is asleep, and is again acquired before returning from this function. </td></tr>
<tr><td class="paramname">timeout</td><td>The amount of time in microseconds to wait. This is a maximum, not a minimum. If the condition is signaled, we will wake up before this time, otherwise the error APR_TIMEUP is returned. </td></tr>
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</dd>
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<h2 class="memtitle"><span class="permalink"><a href="#ga789719a5f02bdab8b8abbc8bddd0406b">◆ </a></span>apr_thread_cond_wait()</h2>
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<td class="memname"><a class="el" href="group__apr__errno.html#gaf76ee4543247e9fb3f3546203e590a6c">apr_status_t</a> apr_thread_cond_wait </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__apr__thread__cond.html#gae8f918d38bf1c58bc09670eee456ae5e">apr_thread_cond_t</a> * </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group__apr__thread__mutex.html#ga95712060ba3a192036416e1ccef1db75">apr_thread_mutex_t</a> * </td>
<td class="paramname"><em>mutex</em> </td>
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<p>Put the active calling thread to sleep until signaled to wake up. Each condition variable must be associated with a mutex, and that mutex must be locked before calling this function, or the behavior will be undefined. As the calling thread is put to sleep, the given mutex will be simultaneously released; and as this thread wakes up the lock is again simultaneously acquired. </p><dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">cond</td><td>the condition variable on which to block. </td></tr>
<tr><td class="paramname">mutex</td><td>the mutex that must be locked upon entering this function, is released while the thread is asleep, and is again acquired before returning from this function. </td></tr>
</table>
</dd>
</dl>
<dl class="section remark"><dt>Remarks</dt><dd>Spurious wakeups may occur. Before and after every call to wait on a condition variable, the caller should test whether the condition is already met. </dd></dl>
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