[Animats]

I spent seven years doing maintenance programming for EXEC 8, the operating system kernel for the UNIVAC 1108. It was first demoed in 1967, and was way ahead of its time. By about 1972, it was running reasonably well. This OS had threads, symmetrical multiprocessing, and async I/O. Written entirely in assembler, it was not fun to work on. When it crashed, a dump was taken to drum, and the dump was then printed, producing a stack of paper about two inches thick, mostly just pages of octal numbers. Analysis involves pencils and colored highlighters, tracking pointers through memory.

Here's the manual.[1]

Amazingly, the descendant of EXEC 8, OS/2200, is still a maintained product, over half a century later.[2] There's even a roadmap out to 2033.

[1] https://archive.org/details/bitsavers_univac1100tiveReferenc...

[2] https://en.wikipedia.org/wiki/OS_2200

[rbanffy]

I was curious about what OS/2200 was in the Unisys lineup. It didn’t fit with MCP and what I understood about it. At some point you could download en emulator that ran on Windows.

It seemed even more user-hostile than MCP.