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How to peek a mutex?

Posted by nachus001 on April 30, 2010
Hi all:

I have a FreeRTOS system compiled and working, but now arised the need to know (from a control task)
if a mutex is free or taken without taking it, this is I need to "peek" the mutex, as when peeking a queue.
Is this possible?

Thanks in advance

RE: How to peek a mutex?

Posted by Richard Damon on April 30, 2010
One way to do this is a take with a 0 tick timeout, and if successful immediately give it back.

RE: How to peek a mutex?

Posted by Richard on April 30, 2010
Semaphores and queues use the same data structures. I have not actually tried, but think you could probably pass a semaphore handle into xQueuePeek() successfully. Give it a test to see.


RE: How to peek a mutex?

Posted by nachus001 on May 3, 2010
Yeiiii!! it worked!
You must provide that...

if(xQueuePeek((xQueueHandle)THE_mutex,(void *)NULL,(portTickType)NULL) != pdTRUE)

// the mutex is taken

// the mutex is free


Thank you

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