ref_mbx

iref_mbx

Outline

Reference mailbox state.

C format

 ER      ref_mbx (ID mbxid, T_RMBX *pk_rmbx);

 ER      iref_mbx (ID mbxid, T_RMBX *pk_rmbx);

Parameter(s)

I/O	Parameter	Description
I	ID mbxid;	ID number of the mailbox to be referenced.
O	T_RMBX *pk_rmbx;	Pointer to the packet returning the mailbox state.

[Mailbox state packet: T_RMBX]

typedef struct t_rmbx { ID wtskid; /*Existence of waiting task*/ T_MSG *pk_msg; /*Existence of waiting message*/ ATR mbxatr; /*Attribute*/ } T_RMBX;

Explanation

Stores mailbox state packet (ID number of the task at the head of the wait queue, start address of the message packet at the head of the wait queue) of the mailbox specified by parameter mbxid in the area specified by parameter pk_rmbx.

Note For details about the mailbox state packet, refer to "15.2.7 Mailbox state packet".

Return value

Macro	Value	Description
E_OK	0	Normal completion.
E_ID	-18	Invalid ID number. - mbxid < 0x0 - mbxid > Maximum ID number
E_CTX	-25	Context error. - This service call was issued in the CPU locked state.
E_NOEXS	-42	Non-existent object. - Specified mailbox is not registered.