Having fairly recently developed such a subsystem I can confirm that the General Purpose Subsystem Access Method (I believe that's what the acronym stands for, our systems in Dallas are down today so I can't check directly) is a decent introduction, although it glosses over a lot of issues which need to be resolved for a practical stable application, if you're doing something non-trivial. Also the iefssi, iefssvt, iefssvti descriptions in Using The Subsystem Interface and Auth Assembler Reference are required reading.
As far as accessing DD parameters is concerned we needed to scan the text in the C/I exit and look up the RB chain in Group Allocation to find the Dynalloc SVC parameters in order to get all we needed. So there's some quite interesting work involved. -----Ursprüngliche Nachricht----- Von: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] Im Auftrag von Anthony Fletcher Gesendet: Sonntag, 15. Juli 2012 02:35 An: IBM-MAIN@LISTSERV.UA.EDU Betreff: JCL DD SUBSYS - how to write the SUBSYS Has anyone found where there is documentation on how to code a SUBSYSTEM that could be the target of a JCL DD SUBSYS=(xyz,abc) statement? I am looking for information on how to code the subsystem itself and how to pick up the DD information and the PARM passed to the subsystem. ---------------------------------------------------------------------- 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
