GOBACK

GOBACK Example

Program Communication Tutorial   

Scenario - Usage of the GOBACK in SUBPROG.

MAINPROG -

----+----1----+----2----+----3----+----4----+----5----+
       IDENTIFICATION DIVISION.
       PROGRAM-ID. MAINPROG.
       AUTHOR. MTH.

       DATA DIVISION.
       WORKING-STORAGE SECTION.
       01 WS-VAR.
          05 WS-INP1      PIC 9(02) VALUE 47. *> Input1
          05 WS-INP2      PIC 9(02) VALUE 25. *> Input2
          05 WS-RESULT    PIC 9(04).          *> Result Variable
		  05 WS-SUBPROG   PIC X908) VALUE 'SUBPROG'.

	   PROCEDURE DIVISION. 

	  * Calling subprogram staically with two inputs 
      * and receiving the result from SUBPROG
           CALL WS-SUBPROG USING WS-INP1, WS-INP2, WS-RESULT.

           DISPLAY "INPUTS:  " WS-INP1 ", " WS-INP2.
           DISPLAY "RESULTS: " WS-RESULT.

           STOP RUN.

SUBPROG -

----+----1----+----2----+----3----+----4----+----5----+
       IDENTIFICATION DIVISION.
       PROGRAM-ID. SUBPROG.
       AUTHOR. MTH.

       DATA DIVISION.
       LINKAGE SECTION.
       01 LK-INP1      PIC 9(02).  *> To receive input1 from MAINPROG
       01 LK-INP2      PIC 9(02).  *> To receive input2 from MAINPROG
       01 LK-RESULT    PIC 9(04).  *> To send result to MAINPROG

	  *Receiving data from main program CALL statement
       PROCEDURE DIVISION USING LK-INP1, LK-INP2, LK-RESULT. 

           COMPUTE LK-RESULT = LK-INP1 * LK-INP2.
           GOBACK.

JCL -

//MATEPKRJ JOB MSGLEVEL=(1,1),NOTIFY=&SYSUID     
//***********************************************
//*  RUN A COBOL PROGRAM 
//***********************************************
//STEP01  EXEC PGM=MAINPROG
//STEPLIB  DD  DSN=MATEPK.COBOL.LOADLIB,DISP=SHR 
//SYSOUT   DD  SYSOUT=*

Output -

INPUTS:  47, 25
RESULTS:  1175

Explaining Example -

In the above example:

  • MAINPROG is the main program, and SUBPROG is the subprogram.
  • MAINPROG is coded with STOP RUN which returns the control to the system where the control is received.
  • SUBPROG is coded with GOBACK that needs to return the control to the main program from where the control received.
  • WS-INP1 and WS-INP2 are the inputs passed from MAINPROG to the SUBPROG. SUBPROG receives the data into LK-INP1, LK-INP2 from MAINPROG, multiplies those values, and places the result into LK-RESULT.
  • SUBPROG returns the output in LK-RESULT, and MAINPROG displays the result received from SUBPROG.