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About usModule 4: JCL DD Statement
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SPECIAL DD PARAMETER/STATEMENTS
DUMMY Parameter
As a name suggest DUMMY parameter is used to allow program to be executed without actually having files to be present. Sometime we need to perform testing of program, without using actual datasets. In such situation we can use DUMMY or DSN=NULLFILE. DUMMY parameter causes operating system to simulate the existence of file, without actually being there.
Syntax 1:-
//ddname DD DUMMY
Syntax 2:-
//ddname DD DSN=NULLFILE
Example:-
//DEPTJOB JOB A123,’STEVE’
//STEP1 EXEC PGM=PROG1
//DATA1 DD DSN=DEPT1.EMP1.DATA1,
// DISP=SHR
//DATA2 DD DSN=DUMMY