- No device or external storage space is to be allocated to the data set.
- No disposition processing is to be performed on the data set.
- For BSAM and QSAM, no input or output operations are to be performed on the data set.
One use of the DUMMY parameter is in testing a program. When testing is finished and you want input or output operations performed on the data set, replace the DD DUMMY statement with a DD statement that fully defines the data set.
Nullify the DUMMY parameter by coding:
//DS1 DD DUMMY,DSNAME=A,DISP=OLD
//JS EXEC PROC=PROC1 //PS.DS1 DD DSNAME=A