Exit program limitations

If your task-related user exit program is invoked at end-of-task, you must understand possible limitations on exit program activity at task-detach.

  • Do not update any CICS® resources at all during a task-detach exit call, because the CICS syncpoint manager is not invoked again for that task. All resources except task-storage have been released by end-of-task.
    Note: Transactions with resource security or command security defined might not run successfully after the terminal has been released. See Resource and command check cross-reference to determine which resources and commands are subject to security checking. Failure to observe these limitations can result in an ABEND AEY7 - NOTAUTH condition arising.
  • It is possible to schedule a new CICS task from your exit program using the EXEC CICS START command and to pass data to a new task. However, the EXEC CICS START command uses a temporary storage queue to pass data to the new transaction. If this queue is defined as recoverable, it is locked to the detaching task. It is never unlocked, because when the task-detach exit call is made, the resources of the detaching task have already been freed. Use of the PROTECT option causes a different problem: the new task can not be scheduled until the next sync point of the detaching task, but no sync point occurs.
  • Do not access remote resources using a task-related user exit program. If you do, you must understand the circumstances in which the function shipping conversation can be terminated.