JCL REFERBACK | Mainframestechhelp
The referback (backward reference) is used to get the information from the previous steps to the current step. This process reduces redundant coding and syntax errors. "*" is used as a referback operator.
Syntax -
*.ddname
*.stepname.ddname
*.proc-name.ddname
*.proc-name.stepname.ddname| *.ddname | Refers the ddname from previous step. | 
| *.stepname.ddname | Refers the ddname from step stepname. | 
| *.proc-name.ddname | Refers the ddname from PROC proc-name. | 
| *.proc-name.stepname.ddname | Refers the ddname from step stepname in PROC proc-name. | 
Examples -
Scenario - Using the DCB of INPUT ddname in the same step.
//STEP02   EXEC PGM=PROG
//INPUT    DD DSN=MTH.INPUT.FILE2,DISP=SHR
//OUTPUT   DD DSN=MTH.OUTPUT.FILE,
//            DISP=(NEW,CATLG,DELETE),
//            SPACE=(CYL,(10,10),RLSE),
//            DCB=*.INPUTIn the above example, MTH.OUTPUT.FILE created with the same DCB as the MTH.INPUT.FILE2.
