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MIT Releases the Source of MULTICS, Father of UNIX

Posted by Zonk on from the linux's-dad's-dad dept.

mlauzon writes "Extraordinary news for computer scientists and the Open Source community was announced over the weekend, as the source code of the MULTICS operating system (Multiplexed Information and Computing Service), the father of UNIX and all modern OSes, has finally been opened. Multics was an extremely influential early time-sharing operating system and introduced a large number of new concepts, including dynamic linking and a hierarchical file system. It was extremely powerful, and UNIX can in fact be considered to be a 'simplified' successor to MULTICS. The last running Multics installation was shut down on October 31, 2000. From now on, MULTICS can be downloaded from an official MIT site (it's the complete MR12.5 source dumped at CGI in Calgary in 2000, including the PL/1 compiler). Unfortunately you can't install this on any PC, as MULTICS requires dedicated hardware, and there's no operational computer system today that could run this OS. Nevertheless the software should be considered to be an outstanding source for computer research and scientists. It is not yet known if it will be possible to emulate the required hardware to run the OS."

9 of 276 comments (clear)

  1. Emulating the Hardware by Unoti · · Score: 4, Insightful
    It is not yet known if it will be possible to emulate the required hardware to run the OS.

    Surely it's possible, it just may not be much fun or very practical. Unless perhaps that old hardware has some black boxes that talk to spirits or do other magic things.

    1. Re:Emulating the Hardware by Cheesey · · Score: 5, Insightful

      It is not yet known if it will be possible to emulate the required hardware to run the OS.

      Run away! They're using reverse psychology!

      "Let's tell the nerds that they can't run MULTICS on simulated hardware, and see how long it takes them to do it!"

      --
      >north
      You're an immobile computer, remember?
  2. Re:Too Complicated to Run? by mikael · · Score: 4, Insightful

    It seems something to do with the way they implemented dynamic linking. Each executable/data page could be shared between multiple processes, with each process having a different set of permissions on that page. On current systems, the permission codes would be associated with that executable/data page, not the process itself.

    Multics - Novel Ideas

    --
    Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
  3. The real legacy of Multics by spaceyhackerlady · · Score: 5, Insightful

    Which is precisely why Unix matters and MULTICS doesn't. The simplifications in Unix are its most important contribution to the art of OS design. For example, we now take it for granted that the OS should implement a disk file as a simple byte stream, with bigger structures, such as records or indexes, being implemented on the application level. But when Unix appeared, that idea was novel and controversial.

    The fact is, Unix was a fresh start, and a damned important one. Unix's creators' biggest accomplishment was clearing out all the feature crud and creating a simple model that has influenced computer science on many levels.

    MULTICS, by contrast, was doomed by its own complexity. The fact that Unix was created from the ashes of Bell Labs' participation in the MULTICS project is just a historical accident.

    I beg to differ.

    At the time of Multics people were just figuring out what a computer should do in an interactive time-sharing environment. People had lots of ideas, and since Multics was, fundamentally, a research OS, they threw them in. Only with experience could they decide which were the good ideas and which were the bad ones. They couldn't know, in advance, which were the winners. They had to try them and see. That is the legacy of Multics.

    ...laura

  4. From the supernatural hardware dept. by hoggoth · · Score: 5, Insightful

    > It is not yet known if it will be possible to emulate the required hardware to run the OS.

    Turing disagrees.

    --
    - For the complete works of Shakespeare: cat /dev/random (may take some time)
  5. Re:Too Complicated to Run? by PitaBred · · Score: 4, Insightful

    But what does the compiler run on? It's still a bootstrapping problem unless the PL1 compiler runs on an available architecture.

    --
    My blog. Good stuff (when I remember to update it). Read it.
  6. Mass commenting by Z-MaxX · · Score: 4, Insightful

    That block comment appears in virtually every source file. It appears to have been added just for this release.

    --
    Dr Superlove 300ml. I use my powers for awesome
  7. Re:Too Complicated to Run? by Zeinfeld · · Score: 5, Insightful
    It seems something to do with the way they implemented dynamic linking. Each executable/data page could be shared between multiple processes, with each process having a different set of permissions on that page. On current systems, the permission codes would be associated with that executable/data page, not the process itself.

    Its not an issue, modern hardware is so much faster than the hardware of the MULTICS era an interpreter can emulate the processor and the memory management in one go.

    A bigger issue would probably be the 36 bit word but even that is just an efficiency issue. Memory is cheap and MULTICS era machines did not have many Mb.

    The bigger question is why go to the trouble. The answer is prior art. MULTICS has been mined as prior art in patent disputes for decades. If its in MULTICS its out of patent.

    --
    Looking for an Information Security student project suggestion?
    Try http://dotcrimeManifesto.com/
  8. A good source of Prior Art by AppleTwoGuru · · Score: 5, Insightful

    Since MULTICS is the father of ALL modern OSes (which would include that trash heap, Windblows) it should provide a multitude of algorithms and processes that people are now trying to Patent and pass off as an Original Invention. This is a very good piece of history. Some people would rather you forget where you came from so they can take advantage of you in the marketplace.