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<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>pthread_condattr_destroy(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>pthread_condattr_destroy(&nbsp;)</strong> - destroy a condition attributes object (POSIX)</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int pthread_condattr_destroy
    (
    pthread_condattr_t * pAttr /* condition variable attributes */
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine destroys the condition attribute object <i>pAttr</i>. It must
not be reused until it is reinitialized.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
Always returns zero.
<p>
</blockquote><h4>ERRNOS</h4><blockquote><p>
None.
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./pthreadLib.html#top">pthreadLib</a></b>, <b><a href="./pthreadLib.html#pthread_cond_init">pthread_cond_init</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_condattr_init">pthread_condattr_init</a>(&nbsp;)</b>

<hr>
<a name="pthread_cond_init"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>pthread_cond_init(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>pthread_cond_init(&nbsp;)</strong> - initialize condition variable (POSIX)</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int pthread_cond_init
    (
    pthread_cond_t *     pCond, /* condition variable */
    pthread_condattr_t * pAttr  /* condition variable attributes */
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
<p>
This function initializes a condition variable. A condition variable
is a synchronization device that allows threads to block until some
predicate on shared data is satisfied. The basic operations on conditions
are to signal the condition (when the predicate becomes true), and wait
for the condition, blocking the thread until another thread signals the
condition.
<p>
A condition variable must always be associated with a mutex to avoid a
race condition between the wait and signal operations.
<p>
If <i>pAttr</i> is NULL then the default attributes are used as specified by
POSIX; if <i>pAttr</i> is non-NULL then it is assumed to point to a condition
attributes object initialized by <b><a href="./pthreadLib.html#pthread_condattr_init">pthread_condattr_init</a>(&nbsp;)</b>, and those are
the attributes used to create the condition variable.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
On success zero; on failure a non-zero error code.
<p>
</blockquote><h4>ERRNOS</h4><blockquote><p>
<b>EINVAL</b>, <b>EBUSY</b>
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./pthreadLib.html#top">pthreadLib</a></b>, <b><a href="./pthreadLib.html#pthread_condattr_init">pthread_condattr_init</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_condattr_destroy">pthread_condattr_destroy</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_broadcast">pthread_cond_broadcast</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_destroy">pthread_cond_destroy</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_signal">pthread_cond_signal</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_timedwait">pthread_cond_timedwait</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_wait">pthread_cond_wait</a>(&nbsp;)</b>

<hr>
<a name="pthread_cond_destroy"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>pthread_cond_destroy(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>pthread_cond_destroy(&nbsp;)</strong> - destroy a condition variable (POSIX)</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int pthread_cond_destroy
    (
    pthread_cond_t * pCond    /* condition variable */
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine destroys the condition variable pointed to by <i>pCond</i>. No
threads can be waiting on the condition variable when this function is
called. If there are threads waiting on the condition variable, then
<b><a href="./pthreadLib.html#pthread_cond_destroy">pthread_cond_destroy</a>(&nbsp;)</b> returns <b>EBUSY</b>.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
On success zero; on failure a non-zero error code.
<p>
</blockquote><h4>ERRNOS</h4><blockquote><p>
<b>EINVAL</b>, <b>EBUSY</b>
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./pthreadLib.html#top">pthreadLib</a></b>, <b><a href="./pthreadLib.html#pthread_condattr_init">pthread_condattr_init</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_condattr_destroy">pthread_condattr_destroy</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_broadcast">pthread_cond_broadcast</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_init">pthread_cond_init</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_signal">pthread_cond_signal</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_timedwait">pthread_cond_timedwait</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_wait">pthread_cond_wait</a>(&nbsp;)</b>

<hr>
<a name="pthread_cond_signal"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>pthread_cond_signal(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>pthread_cond_signal(&nbsp;)</strong> - unblock a thread waiting on a condition (POSIX)</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int pthread_cond_signal
    (
    pthread_cond_t * pCond
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine unblocks one thread waiting on the specified condition
variable <i>pCond</i>. If no threads are waiting on the condition variable then
this routine does nothing; if more than one thread is waiting, then one will
be released, but it is not specified which one.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
On success zero; on failure a non-zero error code.
<p>
</blockquote><h4>ERRNOS</h4><blockquote><p>
<b>EINVAL</b>
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./pthreadLib.html#top">pthreadLib</a></b>, <b><a href="./pthreadLib.html#pthread_condattr_init">pthread_condattr_init</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_condattr_destroy">pthread_condattr_destroy</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_broadcast">pthread_cond_broadcast</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_destroy">pthread_cond_destroy</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_init">pthread_cond_init</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_timedwait">pthread_cond_timedwait</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_wait">pthread_cond_wait</a>(&nbsp;)</b>

<hr>
<a name="pthread_cond_broadcast"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>pthread_cond_broadcast(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>pthread_cond_broadcast(&nbsp;)</strong> - unblock all threads waiting on a condition (POSIX)</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int pthread_cond_broadcast
    (
    pthread_cond_t * pCond
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This function unblocks all threads blocked on the condition variable
<i>pCond</i>. Nothing happens if no threads are waiting on the specified condition
variable.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
On success zero; on failure a non-zero error code.
<p>
</blockquote><h4>ERRNOS</h4><blockquote><p>
<b>EINVAL</b>
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./pthreadLib.html#top">pthreadLib</a></b>, <b><a href="./pthreadLib.html#pthread_condattr_init">pthread_condattr_init</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_condattr_destroy">pthread_condattr_destroy</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_destroy">pthread_cond_destroy</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_init">pthread_cond_init</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_signal">pthread_cond_signal</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_timedwait">pthread_cond_timedwait</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_wait">pthread_cond_wait</a>(&nbsp;)</b>

<hr>
<a name="pthread_cond_wait"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>pthread_cond_wait(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>pthread_cond_wait(&nbsp;)</strong> - wait for a condition variable (POSIX)</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int pthread_cond_wait
    (
    pthread_cond_t *  pCond,  /* condition variable */
    pthread_mutex_t * pMutex  /* POSIX mutex */
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This function atomically releases the mutex <i>pMutex</i> and waits for the
condition variable <i>pCond</i> to be signalled by another thread. The mutex
must be locked by the calling thread when <b><a href="./pthreadLib.html#pthread_cond_wait">pthread_cond_wait</a>(&nbsp;)</b> is called; if
it is not then this function returns an error (<b>EINVAL</b>).
<p>
Before returning to the calling thread, <b><a href="./pthreadLib.html#pthread_cond_wait">pthread_cond_wait</a>(&nbsp;)</b> re-acquires the
mutex.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
On success zero; on failure a non-zero error code.
<p>
</blockquote><h4>ERRNOS</h4><blockquote><p>
<b>EINVAL</b>
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./pthreadLib.html#top">pthreadLib</a></b>, <b><a href="./pthreadLib.html#pthread_condattr_init">pthread_condattr_init</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_condattr_destroy">pthread_condattr_destroy</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_broadcast">pthread_cond_broadcast</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_destroy">pthread_cond_destroy</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_init">pthread_cond_init</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_signal">pthread_cond_signal</a>(&nbsp;)</b>,  
<b><a href="./pthreadLib.html#pthread_cond_timedwait">pthread_cond_timedwait</a>(&nbsp;)</b>

<hr>
<a name="pthread_cond_timedwait"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>pthread_cond_timedwait(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>pthread_cond_timedwait(&nbsp;)</strong> - wait for a condition variable with a timeout (POSIX)</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int pthread_cond_timedwait
    (
    pthread_cond_t *        pCond,   /* condition variable */
    pthread_mutex_t *       pMutex,  /* POSIX mutex */
    const struct timespec * pAbstime /* timeout time */
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This function atomically releases the mutex <i>pMutex</i> and waits for another
thread to signal the condition variable <i>pCond</i>. As with <b><a href="./pthreadLib.html#pthread_cond_wait">pthread_cond_wait</a>(&nbsp;)</b>,
the mutex must be locked by the calling thread when <b><a href="./pthreadLib.html#pthread_cond_timedwait">pthread_cond_timedwait</a>(&nbsp;)</b>
is called.
<p>
If the condition variable