DD DISP Parameter
The DISP parameter specifies how a dataset is to be handled in the job or job step. DISP parameter also tells the system what to do with the dataset after the job step execution.
DISP stands for DISPOSITION and is an optional parameter.
Syntax -
DISP=(status
[,normal-termination-action]
[,abnormal-termination-action])status -
STATUS is used to specify the state of the dataset. The status parameter valid values are -
| Status | Description |
|---|---|
| NEW | Specifies that a new dataset is to be created. If the dataset already exists, an error will occur. The default value if the status is ignored. |
| SHR | Specifies the dataset already exists before the step and used only for reading. Other jobs can share the dataset and use the dataset parallelly. |
| OLD | Specifies the dataset already exists and used with exclusive control on the dataset. If the dataset not exists, steps execution fails. The step takes exclusive (unshared) control of the dataset and other datasets can't use the dataset parallelly. |
| MOD | Specifies the dataset already exists before and used to append the data to the dataset. If it does not exist, a new dataset gets created. The records are to be added to the end of the dataset. The dataset should be sequential. |
Normal-termination-action -
It specifies the system what action needs to be taken on the dataset when the job step completed successfully. Below actions are valid on the dataset when the job step execution is successful -
| Status | Description |
|---|---|
| KEEP | Specifies the dataset is to be retained if step execution is successful. KEEP will not modify any memory allocations done earlier. |
| CATLG | Specifies the dataset is to be cataloged if it is not already cataloged. |
| UNCATLG | Specifies the dataset is to be uncataloged if step execution is successful. UNCATLG does not delete the data from the uncataloged dataset. UNCATLG performs below two tasks -
|
| PASS | Specifies the dataset should pass and used in the further steps. |
| DELETE | Specifies the dataset is to be deleted if step execution is successful. If the EXPDT and RETPD are set for the dataset, the datasets will be kept and DISP parameter ignored. |
Abnormal-termination-action -
It tells the system what action needs to be performed on the dataset when the step execution is unsuccessful (terminates abnormally).
Below actions are valid on the dataset when the job step execution is unsuccessful -
| Status | Description |
|---|---|
| KEEP | Specifies the dataset is to be retained on the volumne if step execution is unsuccessful. KEEP will not modify any memory allocations done earlier. |
| CATLG | Specifies the dataset is to be cataloged if it is not already cataloged. |
| UNCATLG | Specifies the dataset is to be uncataloged if step execution is unsuccessful. UNCATLG does not delete the data from the uncataloged dataset. |
| DELETE | Specifies the dataset is to be deleted if step execution is unsuccessful. If the EXPDT and RETPD are set for the dataset, the datasets will be kept and DISP parameter ignored. |
Default and overrides -
- If the status is ignored, the default is NEW.
- If the normal-termination-action is ignored, the default is DELETE for a NEW dataset and KEEP for an existing dataset. i.e., DISP=(NEW,DELETE,) for new and DISP=(OLD,KEEP,) for existing datasets.
- If the abnormal-termination-action is ignored and the normal-termination-action is coded as PASS, the default is DELETE for a NEW dataset and KEEP for an existing dataset. i.e., DISP=(NEW,PASS,DELETE) for new and DISP=(OLD,KEEP,KEEEP) for existing datasets.
- If the DISP parameter is ignored, the default is a NEW dataset with a disposition of DELETE for normal and abnormal termination dispositions. i.e., DISP=(NEW,DELETE,DELETE).
Examples -
Scenario - Create new PS file.
//STEP10 EXEC PGM=IEFBR14
//DD1 DD DSN=MATEPK.IEFBR14.PSFILE,
// DISP=(NEW,CATLG,DELETE),
// SPACE=(TRK,(3,2),RLSE),
// UNIT=SYSDA,VOLUME=SER=DEVHD4,
// DCB=(DSORG=PS,RECFM=FB,LRECL=80,BLKSIZE=800)The statements request the system to CATLOG the new dataset if the step terminates normally and DELETE the dataset if the step terminates abnormally.