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Source Code for CTSS released

Posted by CmdrTaco on from the but-what-will-run-it dept.

Mainframes ROCK! writes "The source code for the Compatible Time-Sharing System, CTSS, has been released, and the here is the source code. CTSS was one of the first time-sharing operating systems and a direct ancestor of Linux. Developed at MIT in the 1960's on a specially modified IBM 7094 system.; it was developed at Project MAC at MIT. CTSS was first published, as well as operated in a time-sharing environment, in 1961; in addition, it was the system with the first computerized text formatting utility, and one of the very first to have inter-user electronic mail."

5 of 177 comments (clear)

  1. Re:direct ancestor? by motyl · · Score: 3, Interesting

    That only means that many people now call any UNIX system "Linux". In the popular culture, there is no UNIX. They just call it all "Linux".

    Lets see when people will call any Operating System "Linux"? Any guesses?

  2. History of CTSS by Sounder40 · · Score: 4, Interesting
    I have a copy of the paper Melinda Varian did on the history of IBM's operating system called VM/370, VM/SP, VM/ESA and now zVM. I'd call it VM, but that's become a rather generic term. It includes a section on the history of CTSS, and it's very, very interesting. In fact, I would say that this was one of the most influential papers I ever read. Well worth the read.

    I hope Melinda doesn't hunt me down and kill me for causing a /. storm on her web site, but the paper is available at http://pucc.princeton.edu/~melinda/.

    Enjoy.

    --
    A clever person solves a problem, A wise person avoids it. -Einstein
  3. Hmmm by jd · · Score: 3, Interesting
    I know there are patches out there that'll turn Linux into VMS (the FreeVMS project). Linux also supports translations of system calls via the binary compatibility code. Hmmm. It might very well be possible to produce a layer that'll make Linux run CTSS code.


    Fom there, Linux supports user-level kernels, so it would be possible to boot CTSS inside of Linux running as CTSS. Thus completing one of the challanges.


    I'm scared.

    --
    It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
  4. Re:Heritage by laird · · Score: 5, Interesting

    Having worked with people who used Multics (I'm not quite that old, myself) I'd have to disagree. UNIX isn't a "better" OS than MULTICS -- in fact, it was intentionally designed to be a "worse" OS (in being far less sophisticated, and providing far less functionality), but had the pragmatic advantage of running on more widely available, less expensive hardware.

    The shame is that the tradeoffs that made UNIX a success in the 70's are probably not valid any more, and modern operating systems and programming models are still (IMO) largely trapped by design decisions made by UNIX. For example, the artificial separation between how you access RAM and disk costs developers untold amounts of wasted effort. And the idea that you don't have to turn a computer off while adding or removing CPU's, RAM, disks, controllers, etc., is still quite uncommon. And the way all linking was dynamic is way better than the mess we have to deal with now. And it had a very nice multi-processor architecture, where all CPU's had access to all RAM, and through that to all secondary storage, etc.

    Of course, some of these ideas have reemerged in high-end computing (the multicians, see http://www.multicians.org) are still all hard at work making things better. :-) But it's hard to correct for fundamental mistakes (e.g. having to flatten data out into files to make it persistent) without forcing all software to be rewritten. As far as I know, the closest OS to this clean model was NewtonOS...

    --
    Enable 3D printed prosthetics!
  5. Re:CTSS-ITS by Slashamatic · · Score: 4, Interesting
    Not quite right. VMS was a descendent of RSX-11M/M+, which in turn had very little to do with RSX-11D/IAS which bosted some really ugly code. DOS-11 was also known as DOS/BATCH had some bits from RSX-11D/IAS but was really its own very primitive thing. At the time, DOS/BATCH was seen if anything to have some relation to the IBM 1130/1800 operating system which the PDP was taking over from.

    TOPS-20 was somewhat of a rewrite if TOPS-10.

    RT-11 doesn't really relate to RSX. The source code was quite different. However there were some similiarities with one of the command line interpreters (DCL) and some utilities like PIP. It should be noted that PIP (Peripheral Interchange Program) had been knocking around for a long time and then something like it ended up in CP/M.

    I wouldn't really call CP/M a clone of RT, many of the system services and concepts behind them were very different. RT-11 was designed as a lab operating system and had a foregroun/background mechanism built-in, which was less of a hack than CPM's TSRs. The PDP-11 had a very advanced instruction architecture at the time and many concepts did not translate to the 8088.