I am using the Arm7-port with a lpc2290 uC from NXP.
I coded a message-passing framework with allocated buffers which adresses are passed with the message-queuing mechanism. But when i am calling the QueueSendFromISR during an interrupt, may be from an receive buffer indication of an uart-driver, i am not able do detect whether the buffer was sent or not because the QueueSendFromISR does not provide an error when the queue is full and the message was not sent during the ISR routine. But i dont’t free the buffer after that error my memory will get a leakage.
actually i use the uxQueueMessagesWaiting function to get the catually queued members and to compare it with the max number, but if you mean that i must not use this mechanism i will check your proposed way