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is a pointer to a variable that will contain an error code returned by this function.
OS_ERR_NONE
if If no tasks were waiting on the queue. In this case, the return value is also 0.
OS_ERR_MSG_POOL_EMPTY
if If there are no more OS_MSG structures to use to store the message.
OS_ERR_OBJ_PTR_NULL
if If OS_CFG_ARG_CHK_EN is set to 1 in os_cfg.h: if p_q is a NULL pointer.
OS_ERR_OBJ_TYPE
if If OS_CFG_OBJ_TYPE_CHK_EN is set to 1 in os_cfg.h: if p_q is not pointing to a message queue.
OS_ERR_Q_MAX
if If the queue is full and therefore cannot accept more messages.
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