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Poll binary mutex

Posted by Jonas Poulsen on November 5, 2010
The documentation says that is possible to poll the state of a semaphore: "A block time of zero can be used to poll the semaphore" in the xSemaphoreTake section.
I have a hard time making this work.
Polling a semaphore should not change it in any way, or am I confused by the idea of "polling" and "peeking"?

I can see in semphr.h that the xSemaphore cannot set the "just peeking" boolean to true.

#define xSemaphoreTake( xSemaphore, xBlockTime ) xQueueGenericReceive( ( xQueueHandle ) xSemaphore, NULL, xBlockTime, pdFALSE )

Please enlighten me...

BR,
Jonas, DK

RE: Poll binary mutex

Posted by Dave on November 5, 2010
Polling the semaphore will change its state if the semaphore is available, yes you are confused between polling and peeking.

RE: Poll binary mutex

Posted by Jonas Poulsen on November 5, 2010
Thank you for a quick reply :-)
BR, Jonas


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