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How to 'reset' counting semaphore?

Posted by npkz on March 7, 2017

Hello people,

is there any way to set inital count of counting semaphore after the semaphore is created? If I create semaphore like this xSemaphore = xSemaphoreCreateCounting( 10, 0 ), after some time I would like to put semaphore current value to 0 again.

I was thinking to go with for loop uxSemaphoreGetCount times, and do xSemaphoreTake in each iteration, but this function (...GetCount) is not present in v8.2.3 that I am using right now.


How to 'reset' counting semaphore?

Posted by richarddamon on March 7, 2017

You could do xSemaphoreTake() with a timeout of 0 until it fails.

How to 'reset' counting semaphore?

Posted by npkz on March 7, 2017

That's nice idea. Thanks!

How to 'reset' counting semaphore?

Posted by rtel on March 7, 2017

You can probably use xQueueReset() too - you might have to cast the semaphore handle to a queue handle when passing in the parameter to avoid compiler warnings.

How to 'reset' counting semaphore?

Posted by npkz on March 8, 2017

Yes, xQueueReset() works as well. Cast doesn't seem to be needed.

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