ref_mtx

Outline

Reference mutex state.

C format

 ER      ref_mtx (ID mtxid, T_RMTX *pk_rmtx);

Parameter(s)

I/O	Parameter	Description
I	ID mtxid;	ID number of the mutex.
O	T_RMTX *pk_rmtx;	Pointer to the packet returning the mutex state.

[Mutex state packet: T_RMTX]

typedef struct t_rmtx { ID htskid; /*Existence of locked mutex*/ ID wtskid; /*Existence of waiting task*/ } T_RMTX;

Explanation

This service call stores the detailed information of the mutex specified by parameter mtxid (existence of locked mutexes, waiting tasks, etc.) into the area specified by parameter pk_rmtx.

- htskid
Stores whether a task that is locking a mutex exists.

TSK_NONE: No applicable task

Value: ID number of the task locking the mutex

- wtskid
Stores whether a task is queued to the mutex wait queue.

TSK_NONE: No applicable task

Value: ID number of the task at the head of the wait queue

Return value

Macro	Value	Description
E_OK	0	Normal completion.
E_PAR	-17	parameter error. - pk_rmtx == NULL
E_ID	-18	Invalid ID number. - mtxid < 0 - mtxid > VTMAX_MTX
E_CTX	-25	Context error. - This service call was issued from a non-task. - This service call was issued in the CPU locked state. - This service call was issued in the status "PSW.IPL > kernel interrupt mask level".
E_MACV	-26	Memory access violation. - The operand-write access to the area indicated by pk_rmtx has not been permitted to the invoking task
E_NOEXS	-42	Non-existent object. - The mutex specified by mtxid does not exist.