Task states and Application Tag

jegy wrote on Sunday, August 05, 2012:


I know that this question has been around before in this forum, but not led to a general solution, only some specialized partiel solutions.

For syncronizing tasks, I need an utility function, which returns the actual state for the specified xHandle. I mean one of the states READY, RESUMED, RUNNING and BLOCKED.

Other people are recommended to implement their own special version, and I could do something similar.

But I find it is a waste of develop time, code size and execution time that such a general function is not a generel part of the FreeRTOS.

I can solve my problem with a work around, using the application tag functions, but this is really a waste to do parallel monitoring of the state of each task when the information already exist and can be accessed in a general way.

By the way, it would be nice to know if the application tag is initialized by the xTaskCreate(), eeg. to the value NULL?

Thanks for an exellent OS.

Best regards

rtel wrote on Sunday, August 05, 2012:

Normally tasks synchronise with each other using things like semaphores, and don’t need to know their state, so I’m not sure what it is you are trying to achieve.  Could you describe what it is you are wanting to do, maybe there is an alternative.

It would be simple enough to add in an API function that returned the state of a task.  If you really need this, please add it to the feature request tracker (in Sourceforge).

To answer your second question - look at the function prvInitialiseTCBVariables() in tasks.c.  pxTaskTag is initialised to NULL.  No TCB variables are left uninitialised.