You can't, but there are some things that you can do on the fly. You can allocate and free datasets dynamcally with SVC 99, either directly or using one of the IBM provided front ends. e.g., ALLOC, BPXWDYN.
You can do a RDJFCB, modify, e.g., the member name, the file sequence number, then OPEN TYPE=J. You can write a program to call another program with modified parameters. -- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 עַם יִשְׂרָאֵל חַי נֵ֣צַח יִשְׂרָאֵ֔ל לֹ֥א יְשַׁקֵּ֖ר ________________________________________ From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> on behalf of Steff Gladstone <000005c5038228fa-dmarc-requ...@listserv.ua.edu> Sent: Sunday, November 10, 2024 3:51 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Modifying JCL on the fly Caution: This email did not originate from George Mason’s mail system. Do not click links or open attachments unless you recognize the sender and know the content is safe. What is the best way of modifying JCL after the job has been submitted, in order to conditionally add another DDNAME to a JOB STEP? Or perhaps adding parameters to the PARM string on the EXEC statement. We were thinking of using the IEFUSI exit point, allocating a file dynamically before the main program of the job-step is attached. I gather there are also JES2 exits (are they simple exits or the more flexible exit points?) that are appropriate to the task and would be interested to hear advice from other system programmers. Two other questions: are these exits specified in the PARMLIB or via some other mechanism? And what happens if the exit fails in some way? What action does the system take? Thanks in advance, Steff Gladstone ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
