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Semaphore interface addition

Posted by Bill Howell on October 22, 2010
I'm using FreeRTOS V6.0.5, and have noticed that in the semphr.h interfaces that the interface to delete a semaphore is missing.

I realize that underneath it all it's simply a specialization of a queue (as is evidenced by the other macros in semphr.h), and that vQueueDelete works just fine on them. I simply think that for completeness that the following should be added to the interface file:

#define vSemaphoreDelete( xSemaphore ) vQueueDelete( xSemaphore )


RE: Semaphore interface addition

Posted by Richard on October 22, 2010
That is a good idea, and to be honest I didn't realise this was missing. I would be grateful if you could open a Feature Request tracker item for this so it doesn't get lost.

There are dangers associated with deleting both queues and semaphores when tasks are in their blocked lists. Hopefully this is an obvious point, and easy to ensure the lists are empty prior to the queue/semaphore being deleted.


RE: Semaphore interface addition

Posted by Bill Howell on October 25, 2010
Opened a Feature Request to add this interface.

I ran across the need for this interface while creating a set of test cases to compare performance and size differences against other RTOS's.
There are separate pre-test setup and post-test teardown of resources functions to keep the creation/destruction sequencing straight.
I'd have preferred to do all this in C++ with proper RAII usage inside classes, but am constrained to 64kbytes, so no C++ this time!

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