I can offer at least one perspective on Multics, although from a limited viewpoint.
I was an Explorer Scout at post 414, sponsored by Honeywell, in Phoenix, from about 1972 onwards. This was a "high tech" special interest Post, and our interest was computers - no surprise.
Weekly meetings included time using Teletypes (and later nicer terminals) to connect to a GCOS system in Phoenix. Programming in Basic, FORTRAN, COBOL and other arcane languages ensued. As did "an incident". Pretty minor, but yeah, some high school kids "popped" (for some value of "popped") the local GCOS system and got access to some files they shouldn't have. I'm not sure if this was dumpster diving, or a real bug, or just exploiting some employee carelessly setting file permissions to "read and write for the entire system". I strongly suspect the latter.
As a result, all our GCOS accounts were cancelled and we were moved to System M, one of the primary development systems for Multics. As was new and not all common at the time, the entire source code for the entire system was available online - and not just because this was a dev system, this was the norm for all Multics owners. In this way, Multics followed the UNIX model, or maybe they came from a common theme.
The Post took to PL/1 in a big way and delivered some interesting changes to (mostly) the games on the system - vbg (Video BackGammon), chess, yet another space wars clone, and a huge expanded ADVENTURE. There was also some interesting new programming, including finding a way to exploit IPC channels, and another way to crash the front end processor, that led to some emergency bugfixes being rolled out (I later learned) overnight to the Pentagon and "the Fort" customers.
Speaking of which, there was a bit of a kerfluffle when someone who shall remain nameless, innocently asked "I identified all the Multics systems in the site documents, except System N. Where is System N?" in a public forum on System M. I was warned Never To Speak of System "N" Ever Again Or Else.
Over the next 10 years, a lot of my technical life was around Multic. As a Boy Scout, and eventually as a student intern at Honeywell. Throughout college all my engineering programming was done on Multics, mostly in pl1, instead of fortran. As an intern I worked on projects across the GCOS (GCOS-8), Multics and even a little CP-6 spaces. I got to see and hear how different parts of the company saw the GCOS vs Multics conflict, admittedly filtered through the eyes of a still naive intern. Here are some recollections and talking points.
- Multics hardware is too expensive!
- GCOS 8 HW, which would have run Multics, GCOS classic and the someday GCOS 8 was even more expensive)
- Multics HW was expensive because they built and burned-in an entire GCOS system, and then partially took it apart, re-wired the CPU boards and other parts, and then put it back together!A Multics CPU had some boards in common with a GCOS CPU, some were modified boards, and some were completely separate, if I recall correctly. Wirewrap CPU boards in addition to the wirewrapped backplane, which was also (I think) a built-and-then-rewired GCOS backplane.
- Our customers want more batch and less timesharing! - Multics doesn't have a real batch mode!
- which could have easily been addressed with a "dusty deck translator" from GCOS JCL to Multics "absentee" scripts.
- Timesharing is a fad and too expensive - look at how few people our GCOS customers put on TSS!
- yeah, because GCOS TSS was an afterthought - a big pasted-on batch job that remained primitive compared to Multics and other competitors - looking at you TOPS-20, which was also up and coming
- Our profit margins on GCOS SW and HW are better - so we should sell more GCOS!
- Spending money on Multics will take away resources from our bread and butter GCOS, which is where we make money!
- No one cares about PL/1 - all our customers want COBOL and FORTRAN
- which Multics had, and a better COBOL compiler than GCOS - I learned COBOL68 and COBOL74 on both - and along the way found a bug that would crash THE ENTIRE GCOS OPERATING SYSTEM (not just the compiler!) if you mis-spelled "ENVIRONMENT DIVISION" in a COBOL74 program.
- GCOS (formerly GECOS, thankyouverymuch) is the real legacy of GE, not that research project from MIT!!! - Multics is a toy we were paid to make, that will never make a dime!
- There was some rivalry between Phoenix and Billerica(?) that was mostly kept away from "the kids", so we didn't see that in detail but it was there.
- This rivalry seemed to be (in retrospect) two orgs fighting over ever-scarcer resources as the mini/super-mini revolution came on strong. A Multics CPU was pretty much a synchronous 1 MIP machine (per CPU). Of course you could have up to 8(?) CPUs and the I/O bandwidth was light years ahead of the super-minis, but DEC said that the VaX-11/780 was a "1 MIP machine" and it was cheaper than a mainframe, so there!!
Anything else would probably be off topic for TUHS, but with the inter-twined DNA of Multics and UNIX, perhaps this is actually on-topic?
I would point out that I don't think Multics was a victim of UNIX adoption, as that (from my dim recollection) took place years after Multics dev had been mostly capped.
After Multics, my first UNIX system was PWB on a PDP-11. It was quite the change, but led to the rest of my career - BSD, KSOS, SysV, IRIX, Ultrix, SunOS, Solaris, UNICOS, others and eventually Linux.
You never forget your first :-)
Regards,
--tep