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Open Source Red Hat Software

The Mysterious History of the MIT License (opensource.com) 40

Red Hat technology evangelist Gordon Haff explains why it's hard to say exactly when the MIT license created. Citing input from both Jim Gettys (author of the original X Window System) and Keith Packard (a senior member on the X Windows team), he writes that "The best single answer is probably 1987. But the complete story is more complicated and even a little mysterious."

An anonymous reader quotes his article at OpenSource.com, which begins with the X Window System at MIT's "Project Athena" (first launched in 1983): X was originally under a proprietary license but, according to Packard, what we would now call an open source license was added to X version 6 in 1985... According to Gettys, "Distributing X under license became enough of a pain that I argued we should just give it away." However, it turned out that just placing it into the public domain wasn't an option. "IBM would not touch public domain code (anything without a specific license). We went to the MIT lawyers to craft text to explicitly make it available for any purpose. I think Jerry Saltzer probably did the text with them. I remember approving of the result," Gettys added.

There's some ambiguity about when exactly the early license language stabilized; as Gettys writes, "we weren't very consistent on wording." However, the license that Packard indicates was added to X Version 6 in 1985 appears to have persisted through X Version 11, Release 5. A later version of the license language seems to have been introduced in X Version 11, Release 6 in 1994... But the story doesn't end there. If you look at the license used for X11 and the approved MIT License at the Open Source Initiative (OSI), they're not the same. Similar in spirit, but significantly different in the words used.

The "modern" MIT License is the same as the license used for the Expat XML parser library beginning in about 1998. The MIT License using this text was part of the first group of licenses approved by the OSI in 1999. What's peculiar is that, although the OSI described it as "The MIT license (sometimes called called [sic] the 'X Consortium license')," it is not in fact the same as the X Consortium License. How and why this shift happened -- and even if it happened by accident -- is unknown. But it's clear that by 1999, the approved version of the MIT License, as documented by the OSI, used language different from the X Consortium License.

He points out that to this day, this is why "some, including the Free Software Foundation," avoid the term "MIT License" altogether -- "given that it can refer to several related, but different, licenses."
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The Mysterious History of the MIT License

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  • by xxxJonBoyxxx ( 565205 ) on Saturday April 27, 2019 @11:53PM (#58503740)
    >> Haff explains why it's hard to say exactly when the MIT license created.

    The word you were looking for was "was". Please quit shitposting Slashdot from the barstools, folks.
  • by tepples ( 727027 ) <.tepples. .at. .gmail.com.> on Saturday April 27, 2019 @11:54PM (#58503744) Homepage Journal

    The license of Expat, referred to by OSI as the "MIT License" [opensource.org], is the same as the license of X Window System [x.org] with two changes: replacement of "X Consortium" with the more generic "authors", and the removal of a disclaimer of implied trademark license. I've tended to refer to the OSI approved version of this license as "MIT License (Expat variant)". This combines a name recognizable to those familiar with free software licenses in general with a disambiguator that satisfies pedants.

    Speaking of pedants and X: I also use "X11/Linux" to refer to a family of free desktop operating system distributions, in which X is an arguably more salient component than the GNU C library and Coreutils [installgentoo.com], to distinguish them from distributions of a certain smartphone-focused Linux GUI environment.

    • Speaking of pedants and X: I also use "X11/Linux" to refer to a family of free desktop operating system distributions, in which X is an arguably more salient component than the GNU C library and Coreutils

      There's two problems with that. One, the heart and soul of Unix are the kernel and libc. We could argue about which was which for a while if you wanted, but let's skip that. C is central to Unix, and libc is central to C. All those X11 programs are linked to libc, but not all the libc programs are linked to X11. I don't bother calling it anything/Linux, and usually prefer to name distributions, or to say something like "desktop Linux" in the general case.

      The second problem is that they might use Wayland...

      • Take a moment to learn about uclibc and newlib then get back to us.
        • Take a moment to learn about uclibc and newlib then get back to us.

          I'm already well aware of those things. That there are other C libraries doesn't change the fact that the C library is a significant part of what makes the system. Do you have a point?

      • C is central to Unix, and libc is central to C. All those X11 programs are linked to libc

        The Alpine Linux distribution uses musl libc instead of glibc (the GNU implementation of libc). It also uses BusyBox instead of Bash and GNU Coreutils.

        or to say something like "desktop Linux" in the general case.

        "Desktop Linux" without further clarification leaves the door wide open for pedants to pretend that Chrome OS on a Chromebox is a good substitute for X11/Linux.

  • Look at the MIT PC/IP distribution somewhere between 1982 and 1985. I do not know when the X Window System was first distributed, but PC/IP might have been earlier. Unfortunately, I no longer have it on a medium that I have a reader for.
  • by Anonymous Coward

    A later version of the license language seems to have been introduced in X Version 11, Release 6 in 1994...

    Seems to have been? What kind of vague hand wavy crap is that? It unambiguously was changed for X11R6, as can be easily seen by looking at the README.TXT files in the respective source tar files.
    Nobody should be surprised by this really. X11R6 was the first release by the newly independent X Consortium, Inc., after it was booted out of MIT in late 1993. Tightening up the license was deliberate. (Ask me how I know. :-))

  • The summary says that IBM won't use public domain software, but it doesn't say why. Why? I could picture that IBM doesn't want to use something if they're uncertain about the license, but slapping a license on something does not solve that problem.
  • It is mysterious indeed.Well said!!?

We are each entitled to our own opinion, but no one is entitled to his own facts. -- Patrick Moynihan

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