I have a few more additions: 1. These Japanese operating systems are probably worth mentioning:
Hitachi VOS3 Fujitsu MSP Fujitsu XSP VOS3 and MSP are proven forks of IBM MVS/XA (at least, and likely also MVS/ESA). XSP might be a fork of DOS/VSE. (I'm less familiar with that one.) If you want to hang your hat on supported compatibility with real world IBM machines then VOS3 probably wins. As I recall, VOS3 officially runs on z800 and z890 machines, at least. Hitachi built the z800 in a collaboration with IBM, and also for its own domestic sales in Japan, so that one is not a great surprise. To my knowledge, Fujitsu is still nominally in the mainframe business in Japan, and their machines are basically ESA/390 machines. Both MSP and XSP remain ESA (31-bit), as far as I know. Hitachi's Japanese domestic market machines are ESA/390 machines with very modest, non-z/Architecture 64-bit extensions that VOS3 only lightly exploits. Speaking of related machines, did RCA's operating systems like VMOS and TSOS ever run on IBM System/360 machines? 2. TCSC's EDOS/VS and EDOS/VSE were interesting forks of DOS/VS Release 34. EDOS/VS and EDOS/VSE were compatible with machines that did not have virtual storage support, including System/360 machines. That's why they enjoyed some popularity. NCSC produced a UNIX subsystem for EDOS called PWS, inspired by Coherent UNIX. I'm not sure if NCSC ever made PWS available for IBM DOS/VSE and its successors. 3. I don't think anybody mentioned IBM's OS/44 and PS/44 yet. Those were operating systems for the System/360 Model 44, a scientific market machine. 4. I don't think anybody mentioned VM/IX and IX/370 yet, from Interactive Systems Corporation (ISC). Those were different than AIX/370 and AIX/ESA, based on Locus Computing's work. Bell Labs had a UNIX operating system for System/370 even before ISC's products, but I don't know much about that. MVS OpenEdition was the successor to these efforts, although with yet another, different, much better technology base. MVS OpenEdition begat z/OS UNIX System Services. 5. Boston University's VPS/VM traced its roots to McGill University's RACS (later RAX, then MUSIC/SP) operating system. As far as I know VPS/VM always ran under IBM's VM, but perhaps that wasn't required. VPS/VM and MUSIC/SP are thus "cousins," one could argue. 6. TELPAR dates to the early 1970s, but I don't know much about it. I think it's available in open source (PL/360) form, though. Has anybody tried compiling and running it? 7. VP/CSS, developed by National CSS, was an evolution of CP/CMS. VP/CSS had some efficiency advantages back in the 1970s. 8. Some people might classify Jan Jaeger's ZZSA as an operating system, a very basic one. 9. Did the UCSD p-System ever end up on System/370 or System/390 machines? It ended up on almost every other processor. -------------------------------------------------------------------------------------------------------- Timothy Sipples IT Architect Executive, Industry Solutions, IBM z Systems, AP/GCG/MEA E-Mail: [email protected] ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
