Add xSemaphoreCreateBinary() so vSemaphoreCreate() can be deprecated.
This commit is contained in:
Richard Barry
parent
ca2191c6ee
commit
dcf261a3e6
@ -1,5 +1,5 @@
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/*
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FreeRTOS V7.5.3 - Copyright (C) 2013 Real Time Engineers Ltd.
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FreeRTOS V7.5.3 - Copyright (C) 2013 Real Time Engineers Ltd.
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All rights reserved
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VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
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@ -83,6 +83,13 @@ typedef xQueueHandle xSemaphoreHandle;
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* semphr. h
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* <pre>vSemaphoreCreateBinary( xSemaphoreHandle xSemaphore )</pre>
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*
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* This old vSemaphoreCreateBinary() macro is now deprecated in favour of the
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* xSemaphoreCreateBinary() function. Note that binary semaphores created using
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* the vSemaphoreCreateBinary() macro are created in a state such that the
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* first call to 'take' the semaphore would pass, whereas binary semaphores
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* created using xSemaphoreCreateBinary() are created in a state such that the
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* the semaphore must first be 'given' before it can be 'taken'.
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*
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* <i>Macro</i> that implements a semaphore by using the existing queue mechanism.
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* The queue length is 1 as this is a binary semaphore. The data size is 0
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* as we don't want to actually store any data - we just want to know if the
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@ -99,7 +106,7 @@ typedef xQueueHandle xSemaphoreHandle;
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*
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* Example usage:
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<pre>
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xSemaphoreHandle xSemaphore;
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xSemaphoreHandle xSemaphore = NULL;
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void vATask( void * pvParameters )
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{
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@ -110,7 +117,7 @@ typedef xQueueHandle xSemaphoreHandle;
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if( xSemaphore != NULL )
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{
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// The semaphore was created successfully.
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// The semaphore can now be used.
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// The semaphore can now be used.
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}
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}
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</pre>
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@ -122,15 +129,62 @@ typedef xQueueHandle xSemaphoreHandle;
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( xSemaphore ) = xQueueGenericCreate( ( unsigned portBASE_TYPE ) 1, semSEMAPHORE_QUEUE_ITEM_LENGTH, queueQUEUE_TYPE_BINARY_SEMAPHORE ); \
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if( ( xSemaphore ) != NULL ) \
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{ \
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( void ) xSemaphoreGive( ( xSemaphore ) ); \
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( void ) xSemaphoreGive( ( xSemaphore ) ); \
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} \
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}
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/**
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* semphr. h
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* <pre>xSemaphoreTake(
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* xSemaphoreHandle xSemaphore,
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* portTickType xBlockTime
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* <pre>xSemaphoreHandle xSemaphoreCreateBinary( void )</pre>
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*
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* The old vSemaphoreCreateBinary() macro is now deprecated in favour of this
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* xSemaphoreCreateBinary() function. Note that binary semaphores created using
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* the vSemaphoreCreateBinary() macro are created in a state such that the
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* first call to 'take' the semaphore would pass, whereas binary semaphores
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* created using xSemaphoreCreateBinary() are created in a state such that the
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* the semaphore must first be 'given' before it can be 'taken'.
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*
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* Function that creates a semaphore by using the existing queue mechanism.
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* The queue length is 1 as this is a binary semaphore. The data size is 0
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* as nothing is actually stored - all that is important is whether the queue is
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* empty or full (the binary semaphore is available or not).
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*
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* This type of semaphore can be used for pure synchronisation between tasks or
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* between an interrupt and a task. The semaphore need not be given back once
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* obtained, so one task/interrupt can continuously 'give' the semaphore while
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* another continuously 'takes' the semaphore. For this reason this type of
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* semaphore does not use a priority inheritance mechanism. For an alternative
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* that does use priority inheritance see xSemaphoreCreateMutex().
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*
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* @return Handle to the created semaphore.
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*
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* Example usage:
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<pre>
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xSemaphoreHandle xSemaphore = NULL;
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void vATask( void * pvParameters )
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{
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// Semaphore cannot be used before a call to vSemaphoreCreateBinary ().
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// This is a macro so pass the variable in directly.
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xSemaphore = xSemaphoreCreateBinary();
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if( xSemaphore != NULL )
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{
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// The semaphore was created successfully.
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// The semaphore can now be used.
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}
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}
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</pre>
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* \defgroup vSemaphoreCreateBinary vSemaphoreCreateBinary
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* \ingroup Semaphores
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*/
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#define xSemaphoreCreateBinary() xQueueGenericCreate( ( unsigned portBASE_TYPE ) 1, semSEMAPHORE_QUEUE_ITEM_LENGTH, queueQUEUE_TYPE_BINARY_SEMAPHORE )
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/**
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* semphr. h
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* <pre>xSemaphoreTake(
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* xSemaphoreHandle xSemaphore,
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* portTickType xBlockTime
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* )</pre>
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*
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* <i>Macro</i> to obtain a semaphore. The semaphore must have previously been
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@ -168,7 +222,7 @@ typedef xQueueHandle xSemaphoreHandle;
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if( xSemaphore != NULL )
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{
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// See if we can obtain the semaphore. If the semaphore is not available
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// wait 10 ticks to see if it becomes free.
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// wait 10 ticks to see if it becomes free.
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if( xSemaphoreTake( xSemaphore, ( portTickType ) 10 ) == pdTRUE )
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{
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// We were able to obtain the semaphore and can now access the
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@ -176,7 +230,7 @@ typedef xQueueHandle xSemaphoreHandle;
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// ...
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// We have finished accessing the shared resource. Release the
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// We have finished accessing the shared resource. Release the
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// semaphore.
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xSemaphoreGive( xSemaphore );
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}
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@ -195,24 +249,24 @@ typedef xQueueHandle xSemaphoreHandle;
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/**
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* semphr. h
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* xSemaphoreTakeRecursive(
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* xSemaphoreHandle xMutex,
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* portTickType xBlockTime
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* xSemaphoreTakeRecursive(
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* xSemaphoreHandle xMutex,
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* portTickType xBlockTime
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* )
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*
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* <i>Macro</i> to recursively obtain, or 'take', a mutex type semaphore.
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* The mutex must have previously been created using a call to
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* <i>Macro</i> to recursively obtain, or 'take', a mutex type semaphore.
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* The mutex must have previously been created using a call to
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* xSemaphoreCreateRecursiveMutex();
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*
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*
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* configUSE_RECURSIVE_MUTEXES must be set to 1 in FreeRTOSConfig.h for this
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* macro to be available.
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*
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*
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* This macro must not be used on mutexes created using xSemaphoreCreateMutex().
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*
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* A mutex used recursively can be 'taken' repeatedly by the owner. The mutex
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* doesn't become available again until the owner has called
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* xSemaphoreGiveRecursive() for each successful 'take' request. For example,
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* if a task successfully 'takes' the same mutex 5 times then the mutex will
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* A mutex used recursively can be 'taken' repeatedly by the owner. The mutex
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* doesn't become available again until the owner has called
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* xSemaphoreGiveRecursive() for each successful 'take' request. For example,
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* if a task successfully 'takes' the same mutex 5 times then the mutex will
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* not be available to any other task until it has also 'given' the mutex back
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* exactly five times.
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*
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@ -223,7 +277,7 @@ typedef xQueueHandle xSemaphoreHandle;
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* available. The macro portTICK_RATE_MS can be used to convert this to a
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* real time. A block time of zero can be used to poll the semaphore. If
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* the task already owns the semaphore then xSemaphoreTakeRecursive() will
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* return immediately no matter what the value of xBlockTime.
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* return immediately no matter what the value of xBlockTime.
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*
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* @return pdTRUE if the semaphore was obtained. pdFALSE if xBlockTime
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* expired without the semaphore becoming available.
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@ -247,14 +301,14 @@ typedef xQueueHandle xSemaphoreHandle;
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if( xMutex != NULL )
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{
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// See if we can obtain the mutex. If the mutex is not available
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// wait 10 ticks to see if it becomes free.
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// wait 10 ticks to see if it becomes free.
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if( xSemaphoreTakeRecursive( xSemaphore, ( portTickType ) 10 ) == pdTRUE )
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{
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// We were able to obtain the mutex and can now access the
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// shared resource.
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// ...
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// For some reason due to the nature of the code further calls to
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// For some reason due to the nature of the code further calls to
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// xSemaphoreTakeRecursive() are made on the same mutex. In real
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// code these would not be just sequential calls as this would make
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// no sense. Instead the calls are likely to be buried inside
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@ -262,7 +316,7 @@ typedef xQueueHandle xSemaphoreHandle;
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xSemaphoreTakeRecursive( xMutex, ( portTickType ) 10 );
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xSemaphoreTakeRecursive( xMutex, ( portTickType ) 10 );
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// The mutex has now been 'taken' three times, so will not be
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// The mutex has now been 'taken' three times, so will not be
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// available to another task until it has also been given back
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// three times. Again it is unlikely that real code would have
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// these calls sequentially, but instead buried in a more complex
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@ -287,15 +341,15 @@ typedef xQueueHandle xSemaphoreHandle;
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#define xSemaphoreTakeRecursive( xMutex, xBlockTime ) xQueueTakeMutexRecursive( ( xMutex ), ( xBlockTime ) )
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/*
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/*
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* xSemaphoreAltTake() is an alternative version of xSemaphoreTake().
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*
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* The source code that implements the alternative (Alt) API is much
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* simpler because it executes everything from within a critical section.
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* This is the approach taken by many other RTOSes, but FreeRTOS.org has the
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* preferred fully featured API too. The fully featured API has more
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* complex code that takes longer to execute, but makes much less use of
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* critical sections. Therefore the alternative API sacrifices interrupt
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* The source code that implements the alternative (Alt) API is much
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* simpler because it executes everything from within a critical section.
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* This is the approach taken by many other RTOSes, but FreeRTOS.org has the
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* preferred fully featured API too. The fully featured API has more
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* complex code that takes longer to execute, but makes much less use of
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* critical sections. Therefore the alternative API sacrifices interrupt
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* responsiveness to gain execution speed, whereas the fully featured API
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* sacrifices execution speed to ensure better interrupt responsiveness.
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*/
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@ -312,7 +366,7 @@ typedef xQueueHandle xSemaphoreHandle;
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* This macro must not be used from an ISR. See xSemaphoreGiveFromISR () for
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* an alternative which can be used from an ISR.
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*
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* This macro must also not be used on semaphores created using
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* This macro must also not be used on semaphores created using
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* xSemaphoreCreateRecursiveMutex().
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*
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* @param xSemaphore A handle to the semaphore being released. This is the
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@ -320,7 +374,7 @@ typedef xQueueHandle xSemaphoreHandle;
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*
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* @return pdTRUE if the semaphore was released. pdFALSE if an error occurred.
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* Semaphores are implemented using queues. An error can occur if there is
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* no space on the queue to post a message - indicating that the
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* no space on the queue to post a message - indicating that the
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* semaphore was not first obtained correctly.
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*
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* Example usage:
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@ -369,18 +423,18 @@ typedef xQueueHandle xSemaphoreHandle;
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* <pre>xSemaphoreGiveRecursive( xSemaphoreHandle xMutex )</pre>
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*
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* <i>Macro</i> to recursively release, or 'give', a mutex type semaphore.
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* The mutex must have previously been created using a call to
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* The mutex must have previously been created using a call to
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* xSemaphoreCreateRecursiveMutex();
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*
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*
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* configUSE_RECURSIVE_MUTEXES must be set to 1 in FreeRTOSConfig.h for this
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* macro to be available.
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*
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* This macro must not be used on mutexes created using xSemaphoreCreateMutex().
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*
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* A mutex used recursively can be 'taken' repeatedly by the owner. The mutex
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* doesn't become available again until the owner has called
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* xSemaphoreGiveRecursive() for each successful 'take' request. For example,
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* if a task successfully 'takes' the same mutex 5 times then the mutex will
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*
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* A mutex used recursively can be 'taken' repeatedly by the owner. The mutex
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* doesn't become available again until the owner has called
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* xSemaphoreGiveRecursive() for each successful 'take' request. For example,
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* if a task successfully 'takes' the same mutex 5 times then the mutex will
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* not be available to any other task until it has also 'given' the mutex back
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* exactly five times.
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*
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@ -408,14 +462,14 @@ typedef xQueueHandle xSemaphoreHandle;
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if( xMutex != NULL )
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{
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// See if we can obtain the mutex. If the mutex is not available
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// wait 10 ticks to see if it becomes free.
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// wait 10 ticks to see if it becomes free.
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if( xSemaphoreTakeRecursive( xMutex, ( portTickType ) 10 ) == pdTRUE )
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{
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// We were able to obtain the mutex and can now access the
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// shared resource.
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// ...
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// For some reason due to the nature of the code further calls to
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// For some reason due to the nature of the code further calls to
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// xSemaphoreTakeRecursive() are made on the same mutex. In real
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// code these would not be just sequential calls as this would make
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// no sense. Instead the calls are likely to be buried inside
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@ -423,7 +477,7 @@ typedef xQueueHandle xSemaphoreHandle;
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xSemaphoreTakeRecursive( xMutex, ( portTickType ) 10 );
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xSemaphoreTakeRecursive( xMutex, ( portTickType ) 10 );
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// The mutex has now been 'taken' three times, so will not be
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// The mutex has now been 'taken' three times, so will not be
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// available to another task until it has also been given back
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// three times. Again it is unlikely that real code would have
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// these calls sequentially, it would be more likely that the calls
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@ -448,15 +502,15 @@ typedef xQueueHandle xSemaphoreHandle;
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*/
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#define xSemaphoreGiveRecursive( xMutex ) xQueueGiveMutexRecursive( ( xMutex ) )
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/*
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/*
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* xSemaphoreAltGive() is an alternative version of xSemaphoreGive().
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*
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* The source code that implements the alternative (Alt) API is much
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* simpler because it executes everything from within a critical section.
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* This is the approach taken by many other RTOSes, but FreeRTOS.org has the
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* preferred fully featured API too. The fully featured API has more
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* complex code that takes longer to execute, but makes much less use of
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* critical sections. Therefore the alternative API sacrifices interrupt
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* The source code that implements the alternative (Alt) API is much
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* simpler because it executes everything from within a critical section.
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* This is the approach taken by many other RTOSes, but FreeRTOS.org has the
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* preferred fully featured API too. The fully featured API has more
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* complex code that takes longer to execute, but makes much less use of
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* critical sections. Therefore the alternative API sacrifices interrupt
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* responsiveness to gain execution speed, whereas the fully featured API
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* sacrifices execution speed to ensure better interrupt responsiveness.
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*/
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@ -465,8 +519,8 @@ typedef xQueueHandle xSemaphoreHandle;
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/**
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* semphr. h
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* <pre>
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xSemaphoreGiveFromISR(
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xSemaphoreHandle xSemaphore,
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xSemaphoreGiveFromISR(
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xSemaphoreHandle xSemaphore,
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signed portBASE_TYPE *pxHigherPriorityTaskWoken
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)</pre>
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*
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@ -500,7 +554,7 @@ typedef xQueueHandle xSemaphoreHandle;
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{
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for( ;; )
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{
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// We want this task to run every 10 ticks of a timer. The semaphore
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// We want this task to run every 10 ticks of a timer. The semaphore
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// was created before this task was started.
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// Block waiting for the semaphore to become available.
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@ -511,7 +565,7 @@ typedef xQueueHandle xSemaphoreHandle;
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// ...
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// We have finished our task. Return to the top of the loop where
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// we will block on the semaphore until it is time to execute
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// we will block on the semaphore until it is time to execute
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// again. Note when using the semaphore for synchronisation with an
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// ISR in this manner there is no need to 'give' the semaphore back.
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}
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@ -556,13 +610,13 @@ typedef xQueueHandle xSemaphoreHandle;
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/**
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* semphr. h
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* <pre>
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xSemaphoreTakeFromISR(
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xSemaphoreHandle xSemaphore,
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xSemaphoreTakeFromISR(
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xSemaphoreHandle xSemaphore,
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signed portBASE_TYPE *pxHigherPriorityTaskWoken
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)</pre>
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*
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* <i>Macro</i> to take a semaphore from an ISR. The semaphore must have
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* previously been created with a call to vSemaphoreCreateBinary() or
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* <i>Macro</i> to take a semaphore from an ISR. The semaphore must have
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* previously been created with a call to vSemaphoreCreateBinary() or
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* xSemaphoreCreateCounting().
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*
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* Mutex type semaphores (those created using a call to xSemaphoreCreateMutex())
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@ -582,7 +636,7 @@ typedef xQueueHandle xSemaphoreHandle;
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* running task. If xSemaphoreTakeFromISR() sets this value to pdTRUE then
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* a context switch should be requested before the interrupt is exited.
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*
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* @return pdTRUE if the semaphore was successfully taken, otherwise
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* @return pdTRUE if the semaphore was successfully taken, otherwise
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* pdFALSE
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*/
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#define xSemaphoreTakeFromISR( xSemaphore, pxHigherPriorityTaskWoken ) xQueueReceiveFromISR( ( xQueueHandle ) ( xSemaphore ), NULL, ( pxHigherPriorityTaskWoken ) )
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@ -591,25 +645,25 @@ typedef xQueueHandle xSemaphoreHandle;
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* semphr. h
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* <pre>xSemaphoreHandle xSemaphoreCreateMutex( void )</pre>
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*
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* <i>Macro</i> that implements a mutex semaphore by using the existing queue
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* <i>Macro</i> that implements a mutex semaphore by using the existing queue
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* mechanism.
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*
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* Mutexes created using this macro can be accessed using the xSemaphoreTake()
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* and xSemaphoreGive() macros. The xSemaphoreTakeRecursive() and
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* and xSemaphoreGive() macros. The xSemaphoreTakeRecursive() and
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* xSemaphoreGiveRecursive() macros should not be used.
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*
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* This type of semaphore uses a priority inheritance mechanism so a task
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* 'taking' a semaphore MUST ALWAYS 'give' the semaphore back once the
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* semaphore it is no longer required.
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*
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* Mutex type semaphores cannot be used from within interrupt service routines.
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* This type of semaphore uses a priority inheritance mechanism so a task
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* 'taking' a semaphore MUST ALWAYS 'give' the semaphore back once the
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* semaphore it is no longer required.
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*
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* See vSemaphoreCreateBinary() for an alternative implementation that can be
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* used for pure synchronisation (where one task or interrupt always 'gives' the
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* semaphore and another always 'takes' the semaphore) and from within interrupt
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* Mutex type semaphores cannot be used from within interrupt service routines.
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*
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* See vSemaphoreCreateBinary() for an alternative implementation that can be
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* used for pure synchronisation (where one task or interrupt always 'gives' the
|
||||
* semaphore and another always 'takes' the semaphore) and from within interrupt
|
||||
* service routines.
|
||||
*
|
||||
* @return xSemaphore Handle to the created mutex semaphore. Should be of type
|
||||
* @return xSemaphore Handle to the created mutex semaphore. Should be of type
|
||||
* xSemaphoreHandle.
|
||||
*
|
||||
* Example usage:
|
||||
@ -625,7 +679,7 @@ typedef xQueueHandle xSemaphoreHandle;
|
||||
if( xSemaphore != NULL )
|
||||
{
|
||||
// The semaphore was created successfully.
|
||||
// The semaphore can now be used.
|
||||
// The semaphore can now be used.
|
||||
}
|
||||
}
|
||||
</pre>
|
||||
@ -639,32 +693,32 @@ typedef xQueueHandle xSemaphoreHandle;
|
||||
* semphr. h
|
||||
* <pre>xSemaphoreHandle xSemaphoreCreateRecursiveMutex( void )</pre>
|
||||
*
|
||||
* <i>Macro</i> that implements a recursive mutex by using the existing queue
|
||||
* <i>Macro</i> that implements a recursive mutex by using the existing queue
|
||||
* mechanism.
|
||||
*
|
||||
* Mutexes created using this macro can be accessed using the
|
||||
* xSemaphoreTakeRecursive() and xSemaphoreGiveRecursive() macros. The
|
||||
* Mutexes created using this macro can be accessed using the
|
||||
* xSemaphoreTakeRecursive() and xSemaphoreGiveRecursive() macros. The
|
||||
* xSemaphoreTake() and xSemaphoreGive() macros should not be used.
|
||||
*
|
||||
* A mutex used recursively can be 'taken' repeatedly by the owner. The mutex
|
||||
* doesn't become available again until the owner has called
|
||||
* xSemaphoreGiveRecursive() for each successful 'take' request. For example,
|
||||
* if a task successfully 'takes' the same mutex 5 times then the mutex will
|
||||
* A mutex used recursively can be 'taken' repeatedly by the owner. The mutex
|
||||
* doesn't become available again until the owner has called
|
||||
* xSemaphoreGiveRecursive() for each successful 'take' request. For example,
|
||||
* if a task successfully 'takes' the same mutex 5 times then the mutex will
|
||||
* not be available to any other task until it has also 'given' the mutex back
|
||||
* exactly five times.
|
||||
*
|
||||
* This type of semaphore uses a priority inheritance mechanism so a task
|
||||
* 'taking' a semaphore MUST ALWAYS 'give' the semaphore back once the
|
||||
* semaphore it is no longer required.
|
||||
*
|
||||
* Mutex type semaphores cannot be used from within interrupt service routines.
|
||||
* This type of semaphore uses a priority inheritance mechanism so a task
|
||||
* 'taking' a semaphore MUST ALWAYS 'give' the semaphore back once the
|
||||
* semaphore it is no longer required.
|
||||
*
|
||||
* See vSemaphoreCreateBinary() for an alternative implementation that can be
|
||||
* used for pure synchronisation (where one task or interrupt always 'gives' the
|
||||
* semaphore and another always 'takes' the semaphore) and from within interrupt
|
||||
* Mutex type semaphores cannot be used from within interrupt service routines.
|
||||
*
|
||||
* See vSemaphoreCreateBinary() for an alternative implementation that can be
|
||||
* used for pure synchronisation (where one task or interrupt always 'gives' the
|
||||
* semaphore and another always 'takes' the semaphore) and from within interrupt
|
||||
* service routines.
|
||||
*
|
||||
* @return xSemaphore Handle to the created mutex semaphore. Should be of type
|
||||
* @return xSemaphore Handle to the created mutex semaphore. Should be of type
|
||||
* xSemaphoreHandle.
|
||||
*
|
||||
* Example usage:
|
||||
@ -680,7 +734,7 @@ typedef xQueueHandle xSemaphoreHandle;
|
||||
if( xSemaphore != NULL )
|
||||
{
|
||||
// The semaphore was created successfully.
|
||||
// The semaphore can now be used.
|
||||
// The semaphore can now be used.
|
||||
}
|
||||
}
|
||||
</pre>
|
||||
@ -693,32 +747,32 @@ typedef xQueueHandle xSemaphoreHandle;
|
||||
* semphr. h
|
||||
* <pre>xSemaphoreHandle xSemaphoreCreateCounting( unsigned portBASE_TYPE uxMaxCount, unsigned portBASE_TYPE uxInitialCount )</pre>
|
||||
*
|
||||
* <i>Macro</i> that creates a counting semaphore by using the existing
|
||||
* queue mechanism.
|
||||
* <i>Macro</i> that creates a counting semaphore by using the existing
|
||||
* queue mechanism.
|
||||
*
|
||||
* Counting semaphores are typically used for two things:
|
||||
*
|
||||
* 1) Counting events.
|
||||
* 1) Counting events.
|
||||
*
|
||||
* In this usage scenario an event handler will 'give' a semaphore each time
|
||||
* an event occurs (incrementing the semaphore count value), and a handler
|
||||
* task will 'take' a semaphore each time it processes an event
|
||||
* (decrementing the semaphore count value). The count value is therefore
|
||||
* the difference between the number of events that have occurred and the
|
||||
* number that have been processed. In this case it is desirable for the
|
||||
* an event occurs (incrementing the semaphore count value), and a handler
|
||||
* task will 'take' a semaphore each time it processes an event
|
||||
* (decrementing the semaphore count value). The count value is therefore
|
||||
* the difference between the number of events that have occurred and the
|
||||
* number that have been processed. In this case it is desirable for the
|
||||
* initial count value to be zero.
|
||||
*
|
||||
* 2) Resource management.
|
||||
*
|
||||
* In this usage scenario the count value indicates the number of resources
|
||||
* available. To obtain control of a resource a task must first obtain a
|
||||
* available. To obtain control of a resource a task must first obtain a
|
||||
* semaphore - decrementing the semaphore count value. When the count value
|
||||
* reaches zero there are no free resources. When a task finishes with the
|
||||
* resource it 'gives' the semaphore back - incrementing the semaphore count
|
||||
* value. In this case it is desirable for the initial count value to be
|
||||
* equal to the maximum count value, indicating that all resources are free.
|
||||
*
|
||||
* @param uxMaxCount The maximum count value that can be reached. When the
|
||||
* @param uxMaxCount The maximum count value that can be reached. When the
|
||||
* semaphore reaches this value it can no longer be 'given'.
|
||||
*
|
||||
* @param uxInitialCount The count value assigned to the semaphore when it is
|
||||
@ -726,7 +780,7 @@ typedef xQueueHandle xSemaphoreHandle;
|
||||
*
|
||||
* @return Handle to the created semaphore. Null if the semaphore could not be
|
||||
* created.
|
||||
*
|
||||
*
|
||||
* Example usage:
|
||||
<pre>
|
||||
xSemaphoreHandle xSemaphore;
|
||||
@ -743,7 +797,7 @@ typedef xQueueHandle xSemaphoreHandle;
|
||||
if( xSemaphore != NULL )
|
||||
{
|
||||
// The semaphore was created successfully.
|
||||
// The semaphore can now be used.
|
||||
// The semaphore can now be used.
|
||||
}
|
||||
}
|
||||
</pre>
|
||||
@ -774,7 +828,7 @@ typedef xQueueHandle xSemaphoreHandle;
|
||||
* If xMutex is not a mutex type semaphore, or the mutex is available (not held
|
||||
* by a task), return NULL.
|
||||
*
|
||||
* Note: This Is is a good way of determining if the calling task is the mutex
|
||||
* Note: This Is is a good way of determining if the calling task is the mutex
|
||||
* holder, but not a good way of determining the identity of the mutex holder as
|
||||
* the holder may change between the function exiting and the returned value
|
||||
* being tested.
|
||||
|
||||
Reference in New Issue
Block a user