xQueueGenericReceive pvBuffer is const?
Posted by Phil
on April 9, 2008
I'm using FreeRTOS for a new, ARM-based project. As part of the initial stages I've been putting together a shim to allow PC-based code development to the FreeRTOS API, using wrappers around pthreads library calls for the task/queue implementation.
One of several potential issue I've found is that the output pvBuffer parameter passed to xQueueGenericReceive() is, it would appear, incorrectly declared as a const pointer to const data. In the API documentation, xQueueReceive()/xQueuePeek() take a void* (although it should probably be a const pointer to non-const data).
As a result, the implementation of xQueueGenericReceive() has to do some casts in the memcpy() call. Am I correct in assuming this is by oversight rather than design?
RE: xQueueGenericReceive pvBuffer is const?
Posted by Richard
on April 9, 2008
It is a legacy thing of trying to compile with many different compilers while simultaneously attempting to get lint to shut up. It is basically nonsense and was removed from the SafeRTOS code. It is my intention to remove it from the FreeRTOS.org code too but it has not caught up quite yet.
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