|
Control Job Processing (IF THEN ELSE) in JCL
There are two ways to control job processing in JCL, One way is by
coding COND parameter either on JOB or on EXEC, Second way is ,
using IF condition.
In previous chapters, we have discussed about COND parameter on both
JOB as well as EXEC.
Now let us discuss about IF condition in JCL
Using IF construct is more powerful than COND.
- The COND parameter on the first step of a job is ignored
However,the IF construct is tested
- We can code symbolic parameters in the IF conditions
- We can code many types of relational-expressions in IF condition
Syntax of IF
//name IF < condition > THEN
.
.
//name1 ELSE
.
.
// ENDIF
The condition (ralational expression) consists of:
Comparison operators
Logical operators
Not (�) operators
Relational expression keywords.
Example JCL
//EXAMPLE JOB
//S1 EXEC MYPROC1
//COND01 IF RC = 0 THEN
//C01OK EXEC MYPROC2
//CONDE ELSE
//C01ELS EXEC MYPROC3
// ENDIF
//* copyright www.mainframegurukul.com
EXPLANATION
In above example, S1 is first job step
In 3 rd line, we check the Recturn code of S1 step
if return code is zero then C01OK step will execute
else step C01ELS will going to execute
A Keyword List
Keyword |
Purpose |
ABEND |
Tests for an abnormal end of a program |
�ABEND |
Tests that an abnormal end of a program did not occur |
ABENDCC |
Examines an ABEND condition code |
RC |
Examines a return code |
RUN |
Tests if a job step executed |
�RUN |
Tests if a job step did not execute |
All the keywords can include a stepname and procstepname to refine
the test to a specific job step.
The format is stepname.procstepname.keyword.
RC - checks a return code.
EXAMPLE JCLs
IF RC = 0 THEN
IF STEP1.RC < 12 THEN
If you not given the stepname, then the highest return code from all
job steps is taken for checking.
ABENDCC - Checks an ABEND condition code
Using ABENDCC we can check System/User completion codes
EXAMPLE
IF ABENDCC = S0C7 THEN
Suppose you want to check error code of particular step,
give stepnname.ABENDCC, If you not given the stepname,
most recent ABEND code that occured is taken for checking
ABEND - checks for an abnormal end of a program
EXAMPLE JCL
IF ABEND THEN
IF STEP4.PROCAS01.ABEND = TRUE THEN
If you not given any stepname, all steps prior to this
condition will be checked
RUN - to check whether a job step executed or not
EXAMPLE JCL
Suppose there is a job which contains STEP2, STEP3,STEP4
I have an if condition for STEP2 and STEP3, if condition
is true then STEP2 will be executed, If condition is false
then STEP3 will be executed
I want to execute STEP4 if STEP2 executes,
we can code in the following way
//CHE01 IF STEP2.RUN THEN
//STEP4 EXEC MYPROC1
// ENDIF
//** copyright www.mainframegurukul.com
|
Either the THEN clause or ELSE clause must contain at least one EXEC statement. |
|
|
You can nest another IF construct after the THEN clause or the ELSE clause.
You can nest IF/THEN/ELSE/ENDIF statement constructs up to 15 levels of nesting. |
|
NEXT CHAPTER TOPIC : Restarting and checkpoint in jcl
|
|