IBM provides some significant help on their COBOL Migration portal here: https://www.ibm.com/docs/en/cobol-zos/6.4?topic=SS6SG3_6.4.0/migration-portal.html
Tom Ross has given SHARE presentations on migration to V5 and then to V6, if you have a SHARE membership check the 2016 and 2017 proceedings archives. He probably also presented them at more recent SHARE conferences as well. FWIW, we are running V6.1 (+ back-ported updates) and have many existing V3.x programs and subroutines working fine without any changes. The rubber hits the road when you need to re-compile an older module to add new function or repair a defect. That's when you need to be aware of what changed and how it might affect your program. Watch out particularly for changes in the way DISPLAY NUMERIC's are handled, that is one of the places our teams have found tacit assumptions that are no longer necessarily true in the V5/6 compiler output code. E.G., in V3/V4 compiled code, a DISPLAY NUMERIC field that contains all SPACES at runtime will successfully compare to the ZEROES literal but will NOT compare successfully to ZEROES in V5/6 compiled code because the hardware instructions output from the compiler for the compare operation have changed. I can't answer authoritatively about CICS V5.6, but since V3/V4 compiled code runs without issue in batch I would tend to assume it will continue to run fine in CICS too, at least for the foreseeable future. IBM's decades of adherence to backward compatibility is a pretty good track record to depend on, but if you have CICS-specific questions I suggest asking again over on CICS-L. HTH Peter -----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Paul Gorlinsky Sent: Thursday, October 6, 2022 12:12 PM To: [email protected] Subject: COBOL V3.2 to COBOL V6.3 conversion effort and Any z/OS or LE limits I have a customer that is still using COBOL V3.2 on z/OS 1.13, 2.2 and 2.4 with CICS V5.3, IMS 15.2 and DB2 V12. Are there any major issues taking them to V6 COBOL ... Are there limits on LE interface with COBOL V3 going forward .. Are there limits on CICS V5.6 interface with COBOL V3 Thanks in advance ... Paul -- This message and any attachments are intended only for the use of the addressee and may contain information that is privileged and confidential. If the reader of the message is not the intended recipient or an authorized representative of the intended recipient, you are hereby notified that any dissemination of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail and delete the message and any attachments from your system. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
