Derleth
September 25, 2004, 1:37am
1
The source code for the seminal CTSS operating system has been released by its owners. This is this thread’s jumping-off point, in addition to being a damned interesting development for those of you who are as into retrocomputing as I am.
What was CTSS compatible with? It was one of the first time-sharing systems, after all , so it wouldn’t have had much to be compatible with. It takes two to tango, and I want to know what the other system was.
(It’s too bad Supnik’s simh package doesn’t include an emulator capable of running this software. But, again, that’s neither here nor there. I presume they’re working on it.)
This page says
CTSS was “compatible” in the sense that FMS [Fortran Monitor System] could be run in B-core as a “background” user, nearly as efficiently as on a bare machine. Background could access some tape units and had a full 32K core image. This feature allowed the Computation Center to make the transition from batch to timesharing gradually, and to retain the ability to run “dusty decks” and software from other institutions.
Thus, it seems like CTSS wasn’t compatible with another timesharing system but with the previous batch system that was used on the 7094.
Derleth
September 25, 2004, 12:57pm
3
Thank you. That’s very interesting.
mks57
September 25, 2004, 1:38pm
4
CTSS was followed by ITS, the Incompatible Timesharing System. I don’t know if it was incompatible with anything in particular, or just a jab at CTSS.