IBM Mainframe Forum

by **michelmadhan** » Thu Apr 07, 2011 10:01 pm

I have 10 steps in a Job.If one step is bypassed then what about the remaining steps, these are executed or not.
For example 4th step is bypassed by writting the true condition on that step. Then what about the execution of the
remaining steps, they are executed or not.
If you take another example this time the 4th step in the job is abended. Then what about the execution of the
remaining steps, they are executed or not.
I want to know about the execution flow of the above two situations.

by **MrSpock** » Thu Apr 07, 2011 10:17 pm

Job steps execute, in order, from top to bottom. What happens in one step does not matter to any other step, other than the instance of a JCL error causing the entire job to be flushed. Now, if you use COND= or IF/THEN/ELSE statements to control the flow of the job steps, then yes, it does matter according to the rules as YOU wrote them.

by **steve-myers** » Fri Apr 08, 2011 12:36 am

MrSpock wrote:Job steps execute, in order, from top to bottom. What happens in one step does not matter to any other step, other than the instance of a JCL error causing the entire job to be flushed. Now, if you use COND= or IF/THEN/ELSE statements to control the flow of the job steps, then yes, it does matter according to the rules as YOU wrote them.

Not necessarily. Consider this -

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//S01 EXEC PGM=RETCODE,PARM=0
//S02 EXEC PGM=RETCODE,PARM=0
//S03 EXEC PGM=RETCODE,PARM=4
// IF RC = 0 THEN
//S04 EXEC PGM=RETCODE,PARM=0
//ADD DD DISP=(,PASS),UNIT=SYSDA,SPACE=(TRK,1)
// ELSE
//S04 EXEC PGM=RETCODE,PARM=0
// ENDIF
//S05 EXEC PGM=RETCODE,PARM=0
//ADD DD DISP=(OLD,PASS),DSN=*.S04.ADD
//S06 EXEC PGM=RETCODE,PARM=0
//S07 EXEC PGM=RETCODE,PARM=0
//S08 EXEC PGM=RETCODE,PARM=0
//S09 EXEC PGM=RETCODE,PARM=0
//S10 EXEC PGM=RETCODE,PARM=0

The RETCODE program translates the PARM data to binary and returns with the value as its return code. In other words, it's just a fancy version of the IEFBR14 utility program

There are two versions of step S04. One version executes and creates a dataset. The second version executes but does not create a dataset. Step S05 uses the dataset created by the first version of step S04. This job skips the first version of step S04 because the highest return code for the job was not 0, so the dataset is not created, so step S05 cannot execute, and it causes the job to fail.

by **NicC** » Fri Apr 08, 2011 10:33 am

But that is just bad design of the procedure. It is the same as coding a logic error in a program. Rubbish gives rubbish. If S05 was dependent on the dataset from S04 (the first one and I am not sure if you are allowed 2 steps with the same name even if they are in different sections of IF-THEN-ELSE) then S05 should have been coded within the THEN

by **Anuj Dhawan** » Tue Apr 12, 2011 10:41 pm

michelmadhan wrote:I have 10 steps in a Job.If one step is bypassed then what about the remaining steps, these are executed or not.
For example 4th step is bypassed by writting the true condition on that step. Then what about the execution of the
remaining steps, they are executed or not.
If you take another example this time the 4th step in the job is abended. Then what about the execution of the
remaining steps, they are executed or not.
I want to know about the execution flow of the above two situations.

By "true-condition", if you mean that the RC=0 for this step then subsequent job will get executed UNLESS you've coded some COND or IF/THEN/ELSE on them (which you've mentioned actually and I''l take the benefit of doubt).

In second case, when a Job abends, system will check for the COND=ONLY, if coded on some step, yes - execute that, otherwise Job will be just flushed out of the queue.

by **Anuj Dhawan** » Tue Apr 12, 2011 10:58 pm

And I too agree with MrSpcok and NicC!

by **Akatsukami** » Tue Apr 12, 2011 11:21 pm

NicC wrote:I am not sure if you are allowed 2 steps with the same name even if they are in different sections of IF-THEN-ELSE

I tried it and it is permitted. I agree that it's bad design, though.

by **Robert Sample** » Tue Apr 12, 2011 11:37 pm

From the JCL Reference manual:

16.1.2 Name Field

A stepname is optional, but is needed for the following. When a stepname is needed, it must be unique within the job, including stepnames in any procedures called by the job. If stepnames are not unique within the job, results might be unpredictable; but in most cases, references to non-unique stepnames will resolve to the first occurrence of that stepname.

Referring to the step in later job control statements.

Overriding parameters on an EXEC statement or DD statement in a cataloged or in-stream procedure step.

Adding DD statements to a cataloged or in-stream procedure step. However, a stepname is not required when adding to the first step in a procedure.

Performing a step or checkpoint restart at or in the step.

Identifying a step in a cataloged or in-stream procedure.

by **Anuj Dhawan** » Wed Apr 13, 2011 1:08 pm

Yes, using same name for multple-steps is permitted

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000007 //STEP001 EXEC PGM=SORT
000008 //SORTIN DD *
000009 AAABBB 100
000010 CCCDDD 100
000011 222555 200
000012 //SORTOUT DD SYSOUT=*
000013 //SYSIN DD *
000014 OPTION COPY
000015 INREC FIELDS=(4,3,1,3,7,73)
000016 //SYSOUT DD SYSOUT=*
000017 //*
000018 //STEP001 EXEC PGM=SORT
000019 //SORTIN DD *
000020 AAABBB 100
000021 CCCDDD 100

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Display Filter View Print Options Help
-------------------------------------------------------------------------------
SDSF JOB DATA SET DISPLAY - JOB QANUJ (JOB16077) DATA SET DISPLAYED
COMMAND INPUT ===> SCROLL ===> CSR
NP DDNAME StepName ProcStep DSID Owner C Dest Rec-Cnt Page
JESMSGLG JES2 2 ANUJ 0 LOCAL 24
JESJCL JES2 3 ANUJ 0 LOCAL 19
JESYSMSG JES2 4 ANUJ 0 LOCAL 53
SORTOUT STEP001 105 ANUJ 0 LOCAL 3
SYSOUT STEP001 106 ANUJ 0 LOCAL 22
SORTOUT STEP001 107 ANUJ 0 LOCAL 3
SYSOUT STEP001 108 ANUJ 0 LOCAL 22

This was a simple case. However, in more practical conditions - I vaguely recall, restart was a nightmare at one of the shops -- and this is one of the points from manuals oo, Robert has pointed to.

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