The dequeue function, Response and reason values for enqueue, Response and reason values for dequeue – IBM SC33-1683-02 User Manual

Page 351

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However, as no recovery services are provided for abending global user exits,
CICS ensures that any outstanding XPI enqueues are dequeued automatically
when the dispatcher task terminates. Note that if the dispatcher task is running
a CICS transaction, the dispatcher task terminates when the CICS transaction
terminates (whether normally or abnormally).

Normally enqueues are owned by the requesting transaction, which contains
units of work (UOWs), and these are used to anchor the enqueue control
blocks. The XPI, however, does not require a transaction environment, and
global user exits may be invoked under dispatcher tasks which have no
transactions or UOWs.

PURGEABLE(YES|NO)

specifies whether a purge (or timeout) request against the task is to be honored
if the requesting dispatcher task has to wait for the enqueue.

WAIT(YES|NO)

specifies whether the dispatcher task is to wait if the resource is currently
enqueued to another dispatcher task.

RESPONSE and REASON values for ENQUEUE

RESPONSE

REASON

OK

None

EXCEPTION

ENQUEUE_BUSY
ENQUEUE_LOCKED
ENQUEUE_DISABLED
LIMIT_EXCEEDED
SYSENQ_FAILURE

PURGED

TASK_CANCELLED
TIMED_OUT

The DEQUEUE function

The DEQUEUE function is provided on the DFHNQEDX macro call. It releases a
resource previously enqueued by an ENQUEUE function call.

DEQUEUE

DFHNQEDX [CALL,]

[CLEAR,

[IN,

FUNCTION(DEQUEUE),

{ENQUEUE_TOKEN,|

ENQUEUE_NAME1(address,length)[ENQUEUE_NAME2(address,length)],}

[OUT,

RESPONSE (name1 | *),

REASON(name1 | *)]

The ENQUEUE_TOKEN, ENQUEUE_NAME1, and ENQUEUE_NAME2 parameters
are the same as in the ENQUEUE function call.

RESPONSE and REASON values for DEQUEUE

RESPONSE

REASON

OK

None

EXCEPTION

ENQUEUE_NOT_OWNED
ENQUEUE_LOCKED

enqueue domain functions

Chapter 3. The user exit programming interface (XPI)

319

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