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emptying a queue

Posted by Alessandro de Manzano on March 11, 2010

I'm still newbie with FreeRTOS, so I hope my questions are not (much) stupid..

How can I empty a queue ?

Sometimes I have the need to just ignore every data which could be in a queue until that moment (think about a keyboard buffer, for example)
Currently I do a simple loop of xQueueReceive until it gets data (and ignore it), but I guess I could do something more efficient..

Thanks in advance,


A. de Manzano

RE: emptying a queue

Posted by Richard on March 11, 2010
The loop is probably the best thing. You could delete then re-create the queue (I have not done that in a long time!) provided the items it holds are not dynamically allocated. If they were dynamically allocated then you would loose references to items that were queued and therefore leak memory.


RE: emptying a queue

Posted by Alessandro de Manzano on March 13, 2010
Currently my data is not dynamically allocated, it's simple value data (like serial I/O, etc.), so I could do that, but IMHO the less memory is allocated/freeed, the best ;)
Just for curiosity, why there is not a xQueueEmpty() method (atomic action) ? Just because it's not so often needed ?
Thanks for answer!

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