paulgboul...@aim.com (Paul Gilmartin) writes: > I've long wondered, if sequence numbers are so valuable, why > haven't they spread outside the progeny of unit record systems?
cms multi-level source update infrastructure relied on sequence numbers ... started out with cp67/cms and the cms "update" command which applied a single update file ... used control commands that inserted, replaced, deleted based on sequence numbers of the source file ... output file typically treated as temporary for compile/assemble. at the univ., I was making so many cp67/cms source changes that I created a pre-processor for update ... that added extra field to the insert&replace control statements (aka "$") that would generate sequence numbers of the new lines (otherwise they had to be manually entered/typed). later in early 70s ... there was large "exec" wrapper that supported multiple updates in specified sequence. there was a joint development effort with endicott that added 370 virtual machine simulation to cp67 (that ran on 360/67) ... including new instructions and virtual memory support that had several differences from 360/67. There was "base" set of local enhancements to cp67 ... referred to as the "L" updates ... then could apply the "H" updates to provide option for 370 virtual machines (in addition to 360 virtual machines), and then could apply the "I" updates which modified cp67 to run on 370 machine (rather than 360/67). "cp67i" was running regularly in 370 virtual machine for a year before the first 370 engineering machine with virtual memory hardware support was operational (a 370/145 in endicott) ... in fact, booting "cp67i" on the engineering machine was part of early validation test for the hardware. turns out boot failed ... because of "errors" in the hardware implementation (cp67i was quickly patched to correspond with incorrect hardware ... and then booted succesfully). By the time of vm370/cms, the multi-level update conventions ... and incorporated into CMS update command (eliminating need for the exec wapper) and various editors. Editors were also modified to have option to generate edit session saved changes as an incremental update file (as opposed to replacing the original file with the changes). There is folklore about HASP/JES2 group had moved to cms source development process ... which resulted in various kinds of problems for exporting into standard POK product release environment. In the mid-80s, Melinda had requested anybody with a copy of the original cp67/cms multi-level update implementation. It turns out that I had complete set on archived tapes in the Almaden datacenter tape library. Her request was timely since a couple months later the Almaden datacenter had an operations problem with mounting random tapes as scratch (destroying large number of tapes, including ones with my archived info from the 70s ... in some cases multiple tapes with replicated copies ... including those with large amount of cp67/cms files). old email exchange with Melinda http://www.garlic.com/~lynn/2006w.html#email850906 http://www.garlic.com/~lynn/2006w.html#email850906b http://www.garlic.com/~lynn/2006w.html#email850908 Melinda's home page has moved: http://web.me.com/melinda.varian/Site/Melinda_Varians_Home_Page.html I had done kindle conversion of her history ... which she now has up: http://web.me.com/melinda.varian/Site/Melinda_Varians_Home_Page_files/neuvm.azw cms update command reference: http://publib.boulder.ibm.com/infocenter/zos/v1r10/topic/com.ibm.zos.r10.asmk200/ap5cms8.htm xedit cms command reference (including mention of update option support) http://publib.boulder.ibm.com/infocenter/zvm/v5r4/topic/com.ibm.zvm.v54.dmsb6/xco.htm note that univ source update uses "down-dates" ... i.e. the "current" source file includes all changes ... but there are history files that allows changes to be "regressed" to earlier versions. the cms "up-dates" process would freeze the original source (for some period of time) and have sequence of incremental source updates that would be applied in sequence to arrive at most up-to-date file to be compiled/assembled. -- virtualization experience starting Jan1968, online at home since Mar1970 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
