Periodic mandatory recompiles would have saved us a lot of grief. Take companies that lost their source code - please!
-- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> on behalf of Charles Mills <charl...@mcn.org> Sent: Monday, December 16, 2019 3:56 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Backward compat--how far? I would guess most basic applications and simple system utilities from OS/360 will run unchanged, even in load module form. If you have an IEBCOPY dump on a medium you can read I would guess you could restore it and run it under z/OS V2R4. That's pretty new source code you show. <g> I don't think of RMODE/AMODE as old stuff, but I guess it is all relative. Certainly the code you post below (if completed) would assemble, link and run without error. It *is* quite an achievement. I am personally perhaps counter-usual-wisdom in that I wonder if the 100% slavish compatibility was an over-learning of the lessons of Future System on IBM's part. I wonder if the guaranteed compatibility has given customers permission to ignore the platform in their management thought process. "It will always work whether we invest in it or not." https://secure-web.cisco.com/1-ry1Bem8_GwQbwjDvmxdKfzaws5AK2bfg-MQGwsTBWMdb_GCI6wgaa_gt5rVwB4oXRp-2G-YT8XTwe1HGBJEAdta9HfgrvN0Ov7Jf0drFlXESQi41lUx-_MBAb2K8QRdoAoM042lxkn_qTzuLLChYGsdhs32fhnGOSMjiz1hKql4-HAsV6d_mmQhY7Q7zoe6FFFB3NSntf8v6W7XnwLz3G00diC2VwVm-oN9XEXhXhx3ICB4If5rlEJP8bASvBcHyyopNgKf-_7SAQ8UoijzmCndhNObLCIy5-fQMwLQCqioa9puVto2Ao8LHJIvJbmR0b2F8S5OqSVB2ulIG2o7cLiHiB3vkWYOowVT3vrKsjgBAJOeEogzyK0FemJCz9PQ_Vu7a5rzogcYOQqjqMLUuND8qidaRwsxg8IMStI850u4Q6c3VfwIMRcgKnvROf5x/https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FIBM_Future_Systems_project if you don't know what I am referring to, especially the last paragraph under Project End. Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Rupert Reynolds Sent: Monday, December 16, 2019 12:48 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Backward compat--how far? Another question, purely out of interest: Can the old MVS/SP code still run unchanged? I reminisced with a friend about the day he whinged about a 64k code segment size on Intel micros and I out-whinged him with a 4k code CSECT :-) Can a modern z/OS installation still assemble, link and run the old stuff, such as the typical local utilities we all saw: MYPROG CSECT MYPROG RMODE ANY MYPROG AMODE 24 STM 14,12,12(13) USING ... If so, that's quite an achievement, both in the changes and the flexibility of the original design! ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN pa ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN