IBM SC33-1683-02 - Manual (Page 345)

RESPONSE and REASON values for WAIT_MVS:
RESPONSE REASON
OK None
EXCEPTION None
DISASTER None
INVALID None
KERNERROR None
PURGED TASK_CANCELLED
TIMED_OUT
Notes:
1. For more detail, refer to the explanation of RESPONSE and REASON in
“General form of an XPI call” on page 286.
2. ‘TIMED_OUT’ is returned if the INTERVAL expires, or if a deadlock time-out
interval expires.
3. ‘TASK_CANCELLED’ means that the task has been canceled by operator action
or by an application command.
The CHANGE_PRIORITY call
CHANGE_PRIORITY allows the issuing task to change its own priority. It cannot be
used to change the priority of another task. This command causes the issuing task
to release control, and so provide other tasks with the opportunity to run.
CHANGE_PRIORITY
DFHDSATX [CALL,]
[CLEAR,]
[IN,
FUNCTION(CHANGE_PRIORITY),
PRIORITY(name1 | (Rn) | decimalint | literalconst),]
[OUT,
[OLD_PRIORITY(name1 | (Rn)),]
RESPONSE(name1 | *),
REASON(name1 | *)]
OLD_PRIORITY(name1 | (Rn))
returns the previous priority of the issuing task.
name1
The name of a 1-byte field where the task’s previous priority is stored
(Rn) A register in which the low-order byte receives the previous priority
value and the other bytes are set to zero.
PRIORITY(name1 | (Rn) | decimalint | literalconst)
specifies the new priority to be assigned to the issuing task.
name1
The name of a 1-byte field, with a value in the range 0 through 255.
(Rn) A register with the low-order byte containing the new priority value.
decimalint
A decimal integer not exceeding 255 in value. Neither an expression
nor hexadecimal notation is allowed.
dispatcher functions
Chapter 3. The user exit programming interface (XPI) 313