rcv_mbx
ER rcv_mbx (ID mbxid, T_MSG **ppk_msg);
typedef struct t_msg_pri { struct t_msg msgque; /*Reserved for future use*/ PRI msgpri; /*Message priority*/ } T_MSG_PRI; |
This service call receives a message from the mailbox specified by parameter mbxid, and stores its start address in the area specified by parameter ppk_msg.
If no message could be received from the target mailbox (no messages were queued to the wait queue) when this service call is issued, this service call does not receive messages but queues the invoking task to the target mailbox wait queue and moves it from the RUNNING state to the WAITING state (message reception wait state).
The receiving WAITING state for a mailbox is cancelled in the following cases, and then moved to the READY state.
Note 1 Invoking tasks are queued to the target mailbox wait queue in the order defined during configuration (FIFO order or priority order).
Note 2 If the receiving WAITING state for a mailbox is forcibly released by issuing rel_wai or irel_wai, the contents of the area specified by parameter ppk_msg will be undefined.