Talk:Compatible Time-Sharing System

From Wikipedia, the free encyclopedia
Jump to: navigation, search
WikiProject Computing / Software (Rated Start-class, Low-importance)
WikiProject icon This article is within the scope of WikiProject Computing, a collaborative effort to improve the coverage of computers, computing, and information technology on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.
Start-Class article Start  This article has been rated as Start-Class on the project's quality scale.
 Low  This article has been rated as Low-importance on the project's importance scale.
Taskforce icon
This article is supported by WikiProject Software.
Note icon
An image has been requested for this article. Please remove the needs-image parameter once the image is added.

Page name[edit]

I thought about moving this to "Compaitble Time-Sharing System", and turning this into a disambig page, but I don't have the energy; the Cray system is so rare, and the MIT system so historic, I'm not sure it's the right move anyway. Noel 19:16, 3 Sep 2003 (UTC)

The system is best known by its abbreviation. I think having a disambiguation page where 99% of all people will go one way is pretty lame, so I think the current setup is the right way to go.
By the way, what was CTSS compatible with? I never could figure that out. [Ans: FMS; see article.]

CTSS Source code[edit]

Paul Pierce's CTSS source archive is at

There you can find a 5MB ZIP of the CTSS listing tape, with everything. Supervisor, commands, salvager, etc. This is a wonderful resource. You'll have to know a little FAP and MAD to understand it. There are even a few programs in AED-0, an Algol variant.

Rob Storey has been posting in alt.folklore.computers about the 7094 emulator he's writing. It has progressed to the point where it can run IBSYS and FORTRAN IV. Some folks suggested that he try CTSS next. Sounds like a great project.

[from alt.folklore.computers]

Cambridge Time Sharing System[edit]

I removed the reference to an IBM "Cambridge Time Sharing System". I don't think there was such a thing. This may have been a conflation of "Cambridge Monitor System" and "TSS" which of course had nothing to do with each other. I also changed the reference from Project MAC to the Comp Center. Trevor Hanson 03:33, 9 December 2006 (UTC)


The statement that users could only use 27K and the "monitor" took 5K is incorrect. It may have been true for FMS but it does not apply to CTSS commands, which could use all 32K. (Just because it is written in a book doesn't make it true. I was there, I remember.) What is the protocol for fixing errors like this so that some weenie doesn't unfix it? Thvv 02:47, 6 March 2007 (UTC)

The key first step is what you did: Discuss it here, and include whatever specifics you can track down. Then fix the article as well as possible. If possible, try to find some kind of documentary evidence, e.g. an old reference manual, and cite it in the text, or at least (if it's something that might be disputed) include a footnote. Your note might be something like this: <ref>CTSS commands could use all 32K. A citation is sought to document this; please see the discussion page.</ref>. Provide your best available information. With luck, somebody else will be able to provide a source. As you know, the intent of Wikipedia to include verifiable information; firsthand knowledge, even if accurate and interesting, does not strictly speaking belong here (otherwise there is no way to weed out false or misremembered firsthand claims). On the other hand, and particularly with technical subjects, most Wikians would prefer to get the facts straight first, and then assemble the citations to back them up. By all means, don't leave known falsehoods in place. At the very least discuss them, and challenge them with a {{fact}} tag. If a citation is wrong, and we know this does happen, then challenge the source on the discussion page. Even the weenies here are generally well-intentioned, and don't want falsehoods to persist. I hope this is helpful input. Trevor Hanson 19:03, 6 March 2007 (UTC)

Influence on Unix[edit]

Dennis Richie, in his paper The UNIX Time-sharing System - A Retrospective (published in the first BSTJ 'Unix' volume) says that "a good case can be made that [Unix] is in essence a modern implementation of MIT's CTSS system. This claim is intended as a compliment to both UNIX and CTSS. Today, more than fifteen years after CTSS was born, few of the interactive systems we know of are superior to it in ease of use; many are inferior in basic design." Ironically, people often speak of Unix as 'a descendant of Multics', and there are some aspects of Unix that are clearly copied from Multics (e.g. the hierarchical file system), but I see the truth to DMR's observation (fundamentally, it is more like CTSS than Multics - no single-level-memory, no dynamic linking, etc, etc - all key concepts in Multics). This seems like something worth adding to the article, but I'm too lazy - I leave it for someone else! Noel (talk) 04:25, 6 February 2012 (UTC)