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git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@754 42af7a65-404d-4744-a932-0658087f49c3
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@ -4697,7 +4697,10 @@ returned to indicate the error:
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A thread attempting to unlock an unlocked mutex will return with an error.</li>
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<li><code>PTHREAD_MUTEX_DEFAULT</code>. The default mutex type (PTHREAD_MUTEX_NORMAL).</li>
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</ul>
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In NuttX, PTHREAD_MUTEX_NORMAL is not implemented. PTHREAD_MUTEX_ERRORCHECK is the <i>normal</i> behavior.</li>
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<p>
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In NuttX, <code>PTHREAD_MUTEX_NORMAL</code> is not implemented. Rather, the behavior described
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for <code>PTHREAD_MUTEX_ERRORCHECK</code> is the <i>normal</i> behavior.
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</p>
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</ul>
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<p>
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<b>Returned Values:</b>
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@ -4786,22 +4789,57 @@ interface of the same name.
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</pre>
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<p>
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<b>Description:</b>
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The mutex object referenced by mutex is locked by calling <code>pthread_mutex_lock()</code>.
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If the mutex is already locked, the calling thread blocks until the mutex
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becomes available. This operation returns with the mutex object referenced
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by mutex in the locked state with the calling thread as its owner.
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</p>
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<p>
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If the mutex type is <code>PTHREAD_MUTEX_NORMAL</code>, deadlock detection is not provided.
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Attempting to relock the mutex causes deadlock. If a thread attempts to unlock
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a mutex that it has not locked or a mutex which is unlocked, undefined behavior
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results.
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</p>
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<p>
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In NuttX, <code>PTHREAD_MUTEX_NORMAL</code> is not implemented. Rather, the behavior described
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for <code>PTHREAD_MUTEX_ERRORCHECK</code> is the <i>normal</i> behavior.
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</p>
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<p>
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If the mutex type is <code>PTHREAD_MUTEX_ERRORCHECK</code>, then error checking is provided.
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If a thread attempts to relock a mutex that it has already locked, an error
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will be returned. If a thread attempts to unlock a mutex that it has not
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locked or a mutex which is unlocked, an error will be returned.
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</p>
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<p>
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If the mutex type is <code>PTHREAD_MUTEX_RECURSIVE</code>, then the mutex maintains the concept
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of a lock count. When a thread successfully acquires a mutex for the first time,
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the lock count is set to one. Every time a thread relocks this mutex, the lock count
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is incremented by one. Each time the thread unlocks the mutex, the lock count is
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decremented by one. When the lock count reaches zero, the mutex becomes available
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for other threads to acquire. If a thread attempts to unlock a mutex that it has
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not locked or a mutex which is unlocked, an error will be returned.
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</p>
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<p>
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If a signal is delivered to a thread waiting for a mutex, upon return from
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the signal handler the thread resumes waiting for the mutex as if it was
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not interrupted.
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</p>
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<p>
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<b>Input Parameters:</b>
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<p>
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<ul>
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<li><code>To be provided</code>.</li>
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<li><code>mutex</code>. A reference to the mutex to be locked.</li>
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</ul>
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<p>
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<b>Returned Values:</b>
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<p>
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If successful, the <I>pthread_mutex_lock()</I> function will return
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zero (<I>OK</I>). Otherwise, an error number will be
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returned to indicate the error:
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If successful, the <I>pthread_mutex_lock()</I> function will return zero (<I>OK</I>).
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Otherwise, an error number will be returned to indicate the error:
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<p>
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<ul>
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<li><code>To be provided</code>. </li>
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</ul>
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<p>Note that this function will never return the error EINTR.</p>
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<b>Assumptions/Limitations:</b>
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<p>
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<b>POSIX Compatibility:</b> Comparable to the POSIX
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@ -4817,22 +4855,31 @@ interface of the same name.
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</pre>
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<p>
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<b>Description:</b>
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The function pthread_mutex_trylock() is identical to <a href="#pthreadmutexlock"><code>pthread_mutex_lock()</code></a>
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except that if the mutex object referenced by mutex is currently locked
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(by any thread, including the current thread), the call returns immediately
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with the errno <code>EBUSY</code>.
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<p>
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If a signal is delivered to a thread waiting for a mutex, upon return from
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the signal handler the thread resumes waiting for the mutex as if it was
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not interrupted.
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</p>
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<p>
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<b>Input Parameters:</b>
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<p>
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<ul>
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<li><code>To be provided</code>.</li>
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<li><code>mutex</code>. A reference to the mutex to be locked.</li>
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</ul>
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<p>
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<b>Returned Values:</b>
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<p>
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If successful, the <I>pthread_mutex_trylock()</I> function will return
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zero (<I>OK</I>). Otherwise, an error number will be
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returned to indicate the error:
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If successful, the <I>pthread_mutex_trylock()</I> function will return zero (<I>OK</I>).
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Otherwise, an error number will be returned to indicate the error:
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<p>
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<ul>
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<li><code>To be provided</code>. </li>
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</ul>
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<p>Note that this function will never return the error EINTR.</p>
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<b>Assumptions/Limitations:</b>
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<p>
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<b>POSIX Compatibility:</b> Comparable to the POSIX
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@ -4849,6 +4896,20 @@ interface of the same name.
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<p>
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<b>Description:</b>
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<p>
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The <code>pthread_mutex_unlock()</code> function releases the mutex object referenced
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by mutex. The manner in which a mutex is released is dependent upon the
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mutex's type attribute. If there are threads blocked on the mutex object
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referenced by mutex when <code>pthread_mutex_unlock()</code> is called, resulting in
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the mutex becoming available, the scheduling policy is used to determine
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which thread shall acquire the mutex. (In the case of <code>PTHREAD_MUTEX_RECURSIVE</code>
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mutexes, the mutex becomes available when the count reaches zero and the
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calling thread no longer has any locks on this mutex).
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</p>
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<p>
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If a signal is delivered to a thread waiting for a mutex, upon return from
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the signal handler the thread resumes waiting for the mutex as if it was
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not interrupted.
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</p>
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<b>Input Parameters:</b>
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<p>
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<ul>
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@ -4864,6 +4925,7 @@ returned to indicate the error:
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<ul>
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<li><code>To be provided</code>. </li>
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</ul>
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<p>Note that this function will never return the error EINTR.</p>
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<b>Assumptions/Limitations:</b>
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<p>
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<b>POSIX Compatibility:</b> Comparable to the POSIX
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