Disposition controlled by DISP parameter

The system processes a data set after its use depending on how the step terminates:

Normal termination disposition: To delete, keep, pass, catalog, or uncatalog the data set when the step terminates normally, code:

   //ddname  DD  DISP=(,DELETE),...
   //ddname  DD  DISP=(,KEEP),...
   //ddname  DD  DISP=(,CATLG),...
   //ddname  DD  DISP=(,UNCATLG),...
   //ddname  DD  DISP=(,PASS),...

Abnormal termination or conditional disposition: To delete, keep, catalog, or uncatalog the data set if the step terminates abnormally, code:

   //ddname  DD  DISP=(,,DELETE),...
   //ddname  DD  DISP=(,,KEEP),...
   //ddname  DD  DISP=(,,CATLG),...
   //ddname  DD  DISP=(,,UNCATLG),...

You should consider coding an abnormal termination disposition every time you create or use a data set. This disposition can be used to keep data sets after a program fails, when they might be needed to determine the cause of the failure. This disposition can also be used to delete data sets in case of program failure, thereby restoring the system environment to what it was before the error. Then the failing job can be rerun without an intervening clean-up job.

Effect of abnormal termination during execution

When a step abnormally terminates but is not automatically restarted, its data sets are disposed of as specified by the abnormal termination disposition. If an abnormal termination disposition is not specified, the normal termination disposition is processed.

Effect of abnormal termination during allocation

If a job step fails during step allocation, the system disposes of the data sets as follows:

Deletes a data set being created in the step.
Keeps a data set that existed before the step.

Effect when no abnormal termination disposition is coded

If a DD statement in an abnormally terminating step requests a data set that was cataloged or kept in an earlier step and if the statement does not specify an abnormal termination disposition, the system uses the disposition specified in the earlier step.

Effect of device type on disposition

The system handles disposition differently for data sets on direct access and on tape. A direct access volume contains a volume table of contents (VTOC). A VTOC describes the non-VSAM data sets and available space on the volume.