Job Cards for Started Tasks
Some time around MVS/ESA V5.1, IBM introduced job card support for
started tasks. To use this feature, the started task JCL must reside
in a dataset specified in either the IEFJOBS or IEFPDSI DD statements
of the master scheduler JCL (MSTJCLxx PARMLIB member). Refer to "MVS
Initialization and Tuning Reference" for some suggestions on how to set
For the purpose of the following examples, I will presume that
a separate IEFJOBS dataset has been allocated.
Adding Accounting Information
A typical member in IEFJOBS could look like this:
//JES2 JOB (8022,BX00) **** JOB CARD SUPPORT
//IEFPROC EXEC JES2
The JCL for JES2 will be picked up from the IEFPDSI concatenation. The
resulting started task JCL could look something like:
//JES2 JOB (8022,BX00),
//IEFPROC EXEC JES2
At this point, we have added some accounting information to the started task.
Now, you are able to add other features to the started task JCL. For instance,
say you wished to change the output characteristics for the started task.
You could do something like this:
//INIT JOB (8024,BX00) **** JOB CARD SUPPORT
//DFLT OUTPUT JESDS=ALL,CLASS=Z
//IEFPROC EXEC INIT
So this started task can have a different sysout class than others.
Another new capability is getting the started task JCL from somewhere else:
//TAPEINI JOB (8100,BX01) **** JOB CARD SUPPORT
//STCJCL JCLLIB ORDER=(TAPELIB.STCJCL)
//TPINIT EXEC TAPEINI
The JCL for TAPEINI will be picked up from TAPELIB.STCJCL.
If you specify the PARM option on the MVS START command; for example,
the specified PARM value will not be used if you are using job cards.
An alternative method of accomplishing the same result, is to set up a
symbolic parameter PRM in the PROC for JES2 which will be substituted
into the PARM value of the EXEC statement and use the command
instead. Your JES2 PROC (in IEFPDSI) would look like:
//JES2 PROC PRM='WARM,NOREQ'
//IEFPROC EXEC PGM=HASJES20,PARM='&PRM',
..... etc ....
If a job card member is not present in the IEFJOBS dataset, then the
started task JCL will be built and work as before.
I have only scratched the surface on this subject. Refer to the chapter
on "Started Tasks" in "MVS JCL Reference" for more information.
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