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If the task receiving the message is waiting for a message to arrive, it will be made ready-to-run. If the receiving task has a higher priority than the task sending the message, the higher-priority task resumes, and the task sending the message is suspended; that is, a context switch occurs. A message can be posted as first-in first-out (FIFO), or last-in-first-out (LIFO), depending on the value specified in the opt argument. In either case, scheduling occurs unless opt is set to OS_OPT_POST_NO_SCHED.
Arguments
p_tcb
is a pointer to the TCB of the task. Note that it is possible to post a message to the calling task (i.e., self) by specifying a NULL pointer, or the address of its TCB.
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If the task’s message queue is full and cannot accept more messages.
Returned Value
None
Notes/Warnings
None