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Caldera releases original unices under BSD license

Posted by Nik on Wed Jan 23, 2002 08:46 PM
from the born-free dept.
q[alex] writes "Caldera International has done a very good thing. They have released the "Ancient" Unices they inherited when they purchased SCO under a "BSD-style" license. The license is available here, instructions on finding the source are here. Caldera (and before that SCO) had required people to obtain a free (as in beer) but somewhat restrictive license in order to get these old sources. The new BSD-style licensing only applies to the 16-bit PDI-11 versions and some of the early 32-bit releases (excluding System III and System V), but it's still very cool."
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  • Yes! (Score:5, Funny)

    by tanuki_x (450933) on Wednesday January 23 2002, @08:56PM (#2891831) Homepage
    Now we can see how these "unix" thingies work and write one that works on PCs!
    • ...depends if you actually think one of those "unix thingies" belongs on a desktop computer. *Places can of worms on table for someone else to open*
      • depends if you actually think one of those "unix thingies" belongs on a desktop computer

        Well, Microsoft is reimplementing VMS and calling it 'Userfriendly', so it's not like they have any room to bitch.

    • Now we can see how these "unix" thingies work

      The whole point is that eunuchs' thingies don't work.

      *whispering*

      Oh, uhh, I mean... never mind.
  • Great! (Score:5, Insightful)

    by twilight30 (84644) on Wednesday January 23 2002, @08:56PM (#2891832) Homepage
    Never would have thought Caldera would have done something as community-oriented as this, given their history of late.

    However, a big thank-you from this Slashdot reader for their act. I appreciate it, and I know I'm not alone...

  • Why is this cool? (Score:4, Insightful)

    by SpookComix (113948) <<moc.liamg> <ta> <ximockoops>> on Wednesday January 23 2002, @08:57PM (#2891836) Homepage Journal
    The new BSD-style licensing only applies to the 16-bit PDI-11 versions and some of the early 32-bit releases (excluding System III and System V), but it's still very cool.

    I don't mean to sound like a stick in the mud here, but why exactly is this cool? This source code was obviously available before, for people who actually needed it. Why, then, is the simple fact that anyone can get to it now a "cool" thing?

    Will this spawn development of breakthrough products? Will this help administrators of these old system finally take control of their network?

    Or is this just another geek trophy to have, print, wave around over coffee, and ultimately collect dust on shelves full of other useless time-wasting trinkets?

    --SC

    • Historical purposes. Developmental and teaching purposes, more importantly.

      • I agree ... the historical value is great. I personally have in my possession PDP-11 V7 sources (with my marked-up changes to the terminal driver to change from Multics-style line editing to DEC-style editing) but have no legal right to distribute them.

        People will probably bitch that the sources have no *future value* and they'll be right. But ... who cares? History is, well, history.
    • by Stan Chesnutt (2253) on Wednesday January 23 2002, @09:00PM (#2891855) Homepage
      It is great to have this available for study. And, this might inspire a whole new generation of PDP-11 emulators so you can sit down and actually run the original bits (emulation of an ASR-33 not considered mandatory).

      Computer Science would also be served well if the original Multics sources/binaries were released. Although it would be much harder to write a Honeywell emulator!
      • by Anonymous Coward on Wednesday January 23 2002, @10:26PM (#2892225)
        Of course, in order to partially emulate an ASR-33, you could perhaps connect an IBM selectric up to your computer while running a looped recording of gunfight and an idling 58 chevy with one blown piston. For the final touch, you could replace the room's light switch with a dimmer switch and wiggle it back and forth whenever you are printing something out.
      • This is a tiny fragment of Multics Source [multicians.org]

        It's only 20 years old, surely we can find more of it?
    • "Will this spawn development of breakthrough products? Will this help administrators of these old system finally take control of their network?"

      Yes and yes. Now developers can do just about anything with the code, and the being able to do so will allow for bettered versions of the original code to replace some of the still antiquated code out there with newer, better versions, as well as improving interoperability with those ancient programs and newer stuff.
    • Or is this just another geek trophy to have, print, wave around over coffee, and ultimately collect dust on shelves full of other useless time-wasting trinkets?


      Yes. Sometimes isn't that what makes life worth living? Not the huge major successes, but just something that temporarily brings a smile to your lips and exclamation to your voice? The things that may not shake the world, but are still cool in their own way?
    • by Dr. Tom (23206) <tomh@nih.gov> on Wednesday January 23 2002, @11:51PM (#2892634) Homepage
      This is why it's cool:

      [~/new/usr/src/games]% gcc -O2 -o wump wump.c
      (syntax errors like =|, =&, and the rand() API changed)
      [~/new/usr/src/games]% gcc -O2 -o wump wump.c
      [~/new/usr/src/games]% wump
      Instructions? (y-n) n
      You are in room 8
      I smell a wumpus
      There are tunnels to 10 6 18
      Move or shoot (m-s) m
      which room? 10
      You are in room 10
      I smell a wumpus
      There are tunnels to 19 8 1
      Move or shoot (m-s) s
      Give list of rooms terminated by 0
      8 6 0
      You slew the wumpus
      Another game? (y-n)
  • Plaintext license (Score:4, Informative)

    by jensend (71114) on Wednesday January 23 2002, @08:59PM (#2891851)
    Here's the text of the license before it gets slashdotted or for those who don't want to bother with PDF:

    January 23, 2002
    Dear UNIX enthusiasts,
    Caldera International, Inc. hereby grants a fee free license that includes the rights use, modify and distribute this named source code, including creating derived binary products created from the source code. The source code for which Caldera
    International, Inc. grants rights are limited to the following UNIX Operating Systems that operate on the 16-Bit PDP-11 CPU and early versions of the 32-Bit UNIX Operating System, with specific exclusion of UNIX System III and UNIX System V and successor operating systems: 32-bit 32V UNIX
    16 bit UNIX Versions 1, 2, 3, 4, 5, 6, 7

    Caldera International, Inc. makes no guarantees or commitments that any source code is available from Caldera International, Inc.
    The following copyright notice applies to the source code files for which this license is granted.
    Copyright(C) Caldera International Inc. 2001-2002. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
    following conditions are met: Redistributions of source code and documentation must retain the above copyright notice, this list of conditions and the
    following disclaimer. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
    All advertising materials mentioning features or use of this software must display the following acknowledgement: This product includes software developed or owned by Caldera International, Inc.
    Neither the name of Caldera International, Inc. nor the names of other contributors may be used to endorse or promote products derived from this software without specific prior written permission.
    USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE FOR
    ANY DIRECT, INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
    OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    Very truly yours,
    /signed/ Bill Broderick
    Bill Broderick
    Director, Licensing Services

    * UNIX is a registered trademark of The Open Group in the US and other countries.
  • by buckrogers (136562) on Wednesday January 23 2002, @09:02PM (#2891865) Homepage
    to play around with the old Lions' Commentary on UNIX 6th Edition with source code by John Lions.

    It is amazing how much you can learn from this old stuff. And now we can discuss, modify, and share the code with each other.

    This is really great! Thanks Caldera!
    • Absolutely. Someone's already put a link to Amazon for the book, so go check it out. It's amazing how damned interesting it is to read it, to see how things like task switching and process creation are actually done. (Keep in mind I came into Unix as a hobby, so I haven't taken any of this in CS courses.)

      Someone was asking up above what the point was. Aside from learning from reading yet more code, this is as close as we can get to original Unix. If I was given the chance to check out the original manuscript for, say, the Revelation of St. John (I'm atheist, but religion fascinates me), I'd jump at the chance to see what changes have been made between the original and what we've got now. You'd learn an awful lot about how things have changed -- not just the book itself but everything else. I think that would apply with Unix just as much.

      Couple things: buckrogers, I downloaded the source for the PDP-11 version a year or so ago. The original tarball has been lost in the mists of hd upgrades, but I do remember not being able to correlate Lions' code sections with the source I downloaded. Has your experience been any different?

      And another thing: I'm sure I went picked up the code -- just the code -- for the PDP-11 version, way back when. Now, though, I can't seem to find it on their site. I thought I checked through the directories pretty thoroughly -- can anyone tell me where it is, or provide a link to their own copy?

      Now, of course, I've got to check out the PDP-11 simulator [freshports.org]. (I'm sure I heard about one that was written in Java, but when I did a search on Google [google.com] it seemed like every damn CS student in the world has built one as a class project...someone else'll have to provide the link.)

      • by Anonymous Coward on Wednesday January 23 2002, @10:49PM (#2892298)
        Try compiling:

        ftp://minnie.tuhs.org/pub/PDP-11/Sims/Supnik_2.3 /s ources/sim_2.3d

        build the pdp11 emulator.

        download an image of the v5 root partition and save the contents below to a file named v5init:

        set cpu 18b
        att rk0 v5root
        boot rk

        from the shell, type "pdp11 v5init". at the boot prompt, type "unix".

        Voila. Remember that "cd" doesn't work, but "chdir" does. The only thing coming close to a backspace key is the # key.
  • by Anonymous Coward on Wednesday January 23 2002, @09:03PM (#2891867)

    I think it's wonderful that Caldera decided, pretty much without even being directly asked, to free the sources to historical Unix.

    It's noteworthy that they decided to do this just a few days after, finally, the successful end of Perry Metzger's long campaign to free the historical Unix *documentation* (perhaps more useful, these days). It sure seems to me that once they seriously considered Perry's request they must have realized the PR benefits they could reap by freeing the source code, too.

    Thanks, Caldera -- and if you too are grateful to Caldera, you should probably be grateful to Perry as well.
  • by Waffle Iron (339739) on Wednesday January 23 2002, @09:04PM (#2891873)
    The good news is you can't have a VM flamewar running on a machine that lacks virtual memory.

    The bad news is: 'TECO' r00ls; 'ed' suX0rs.

    • The bad news is: 'TECO' r00ls; 'ed' suX0rs.

      Foreshadowing Emacs vs. vi? The first version of Emacs was a set of TECO macros [geek-girl.com]. Vi was originally just a visual interface to ex, which was an extended version of ed.

    • Pardon me, but as an old PDP-11 hacker (one who played with Unix in 1974) that dear old machine was perfectly capable of supporting virtual memory.

      As was the PDP-8 (with custom hardware, as built by a local company based on a design suggested by Richie Lary and fleshed-out by me).

      Virtual memory was actually old-hat by then in the mainframe world. I don't argue for chops on those grounds, but these early VM efforts on *minicomputers* were significant.

      Mostly because we were poor, of course :)
  • Original UNIX Source (Score:3, Informative)

    by rusti999 (167057) on Wednesday January 23 2002, @09:05PM (#2891877)
    Wanna see the original UNIX source? Check this book [amazon.com].
  • The source code is actually engraved in stone and the kernel is a small rock.
  • by elbuddha (148737) on Wednesday January 23 2002, @09:25PM (#2891970)


    Their "BSD-style" license is actually the old-style BSD license, which includes the particularly onerous Advertising Clause:
    All advertising materials mentioning features or use of this software must display the following acknowledgement: This product includes software developed or owned by Caldera International, Inc.

    What most people think of now as the BSD license does not contain such a clause, and has not for quite some time.
    • And giving credit where credit's due is a bad thing why, exactly? One of the key motivations for doing Open Source/Free software is the kudos you get, so I really have no problem with authors requiring that licensees not pass the work off as their own.
      • > And giving credit where credit's due is a bad
        > thing why, exactly?

        The problem is the "all advertizing material". Imagine everybody had such clauses in their license. A TV spot for Redhat Linux would be pretty long.

        Disclaimer: IANAL. Simply my understanding of the matter.
    • which includes the particularly onerous Advertising Clause:

      Why, exactly, is this onerous? You should expect to get code that you can basically do anything you want with it and being required to acknowledge the people who gave it to you is too much? I bet you never wrote thank-you notes to your grandparents for your presents, either.

      The current BSD license may not contain this, and there's nothing wrong with that either -- but I don't understand how this is unreasonable.

      I wish M$ was required to print an acknowledgement on every Windows box that mentions that their TCP stack is derived from BSD instead of putting on like they're the only company that's every produced useful software.
      • The Windows TCP stack isn't derived from BSD. A very long time ago they licensed a TCP stack from a company that based their product on the BSD TCP stack. But that was close to a decade ago, the licensing agreement is over, Microsoft implemented their own stack from scratch, and the TCP stack in Windows has no code in common with the BSD TCP stack.
      • Why, exactly, is [the old BSD ad clause] onerous?

        It effectively prohibits you from advertising your product in limited-space media such as a small print ad or the radio, as the acknowledgements required by each author's ad clause would fill up the allotted space or time for the ad.

        You should expect to get code that you can basically do anything you want with it and being required to acknowledge the people who gave it to you is too much?

        The copyright notice does this just fine, thank you very much. "Redistributions ... must retain the above copyright notice, this list of conditions and the following disclaimer."

      • by bugg (65930) on Wednesday January 23 2002, @09:48PM (#2892087) Homepage
        Both you and the other poster in response to the parent are quite mistaken about what the advertising clause means.

        Copyright reproduction clauses exist in *every* version of the BSD license. The license & copyright must be reproduced with the product regardless of the advertising clause. What the advertising clause does is require that in any advertisement for the product, that credit is given. This can be interpreted to apply to things like newspaper ads, where at the bottom they'd have to say "contains code copyright regents of the university of california" or in a radio ad, where they'd have to have one of the voices giving credit... this makes per-word advertising impossible.

        Copyright reproduction clauses are good, advertising clauses are bad. There are webpages out there that can cover the issue in more detail than what I just described.

      • It gives credit to the creator of the software while maintaining the software's [freedom].

        No, the copyright notice does that just fine, thank you very much. From a typical new-BSD license:

        Copyright © 2002 Pinocchio Poppins. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:


        Redistributions of source code and documentation must retain the above copyright notice, this list of conditions and the following disclaimer.

        Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

        GPL'd software doesn't contain an advertising clause, and yet Linus Torvalds still manages to get his name in the copyright notice of every copy of Linux® software out there.

  • I applaud the good folks at Caldera for taking this course of action. This will benefit many people:

    • Folks who continue to use these unices will now have more control over their system.
    • Free operating systems may benefit from the knowledge and experience present in the original unices.
    • Just about anybody who wishes to study and expand the system will now have the ability to do so.

    This is also a good marketing move by Caldera. Hey, what have they got to lose by this? I think they have only to gain.

    xxxxxx O xxxxxx H xxxxxx xxxxxx W xxxxxx E xxxxxx L xxxxxx L xxxxxx

  • by CDWert (450988) on Wednesday January 23 2002, @10:05PM (#2892151) Homepage
    People are scoffing, but oh what a kludge, caldera only did it for the publicity, who cares.

    There is some GOOD code in there, some is crap just like all projects.

    There are/were some code segments that were optimized VERY well, and hy dont laugh I remerber USING a pdp-11.

    Point is the horsepower ot these machines sucked by modern standards, things we take for granted were MAJOR tasks, some of those routines were refined over a lifecycle longer than BSD and Linux combined.

    My dad, a coder starting in the 60 tought me in about 1979, when he handed over his collection of computer mags, Byte and the lot, you can NEVER , EVER have too much source code, good or bad.

    Im could care less what Caldera's motives are theyre a dead fish. When was the last time YOU installed that distro ? BUT they should be congratulated, I agree they should open up the other sources as well, but who am I to ask, hey while youre at it all people reading this post should give me all their old ????, see dosent fly. Its theirs , they bought it, and paid for it, sorta.

    Im gonna grab it asap, there about 4 things I hate in the 2.4.18/2.5 series kernel, BSD IMHO dosent have the solution in theirs either, I keep looking , Im at a mental roadblock so to say(nothing new there) if these sources even point me in the right direction to solve one of those problems I will be etternally greatful
    • by Animats (122034) on Thursday January 24 2002, @01:43AM (#2893015) Homepage
      There is some GOOD code in there, some is crap just like all projects.

      Very true. Two real howlers in PDP-11 UNIX:

      • Dumb scheduler. Three compute-bound processes near the head of the process table would starve out all other processes.
      • Really dumb malloc. O(N^2) speed. It's Knuth's fault. When he discusses memory allocation in the original edition of Fundamental Algorithms, he gives a bad algorithm, says it's bad, and leaves the good one as an exercise for the student. UNIX used the dumb one, right out of the book down to the variable names.
  • BSD code (Score:2, Informative)

    If you want to have access to the Ancient BSD source codes, have a look at CSRG Archive CD-ROMs [mckusick.com].

    I wonder if there are archives of mailing-lists also, since you can't use code without comments :-)
  • # fgrep Vote *.c
    // Vote Adams in '96!

  • by Jester99 (23135) on Wednesday January 23 2002, @10:33PM (#2892253) Homepage
    is really amazing.

    If you ignore the instructions for copying the system from magtape to disk (!), everything else looks very similar to the install notes for most modern unices today....

    They tell you to 'cat' files to the printer, 'tar' together items for backup storage, 'sync' before you turn the machine off, and remember to check 'df' regularly to make sure your users don't fill up the disk, and clean out the /tmp directory periodically.

    Reading documentation written 30 years ago which almost hasn't changed at all is really a beautiful thing. (Well, some things have changed. During bootup, the 'mem' line reports user-available memory in bytes. :)

    Hats off to the developers of a system which is so flexible that hasn't really needed interface changing at all to adapt to 30 years of great changes in computer design and usage!
    • everything else looks very similar to the install notes for most modern unices today...

      You say this like its a good thing? As a technical person I'm ok with it, but I (along with a lot of others) definatley see room for improvement in the areas you mentioned. If the interface has changed as little as you say then I think we've got a lot of work ahead of us if we ever want to be a suitable OS for grandma (say what you will, but I believe there are many people who do want this to happen).

  • SCO charged $100 for this shit. And they had some bullshit license and all of that.

    Now if Caldera open sources UnixWare, I'd be more surprised. That could be really useful. Although I'm not holding my breath.

    Anyway, it's cool of Caldera to do this, albeit I doubt it will mean much in the long run...
  • Maybe you thought this was going to be a funny post. It is not. My claim: it is *wonderful* fun to play with early unices on their original machines. If this news story interests you, you should get yourself a PDP-11 or a VAX.

    You can still find PDP-11s and VAXen if you look hard enough -- sometimes with little or no impact on your wallet. After one year of searching, I possess five 11s and three VAXen, and I've even had to pass on some acquisition opportunities. Plus, while some 11s are serious big iron, some are almost as small as an average PC. More recent VAXen actually do come in average-PC form factors.

    There are also several large and very competent Internet communities centered around these machines. They're not that hard to locate. Join one of these, and you've got nearly instant help with getting yourself set up and running. Need tapes? Need that paper tape controller board? No problem. The only catch, of course, is that you'll have to do the same one day for all the future vintage hardware fans that are just now being born (as in babies, children, offspring).

    So go grab yourself a PDP-11/73 and a VT220 and throw 2.11BSD on it. You'll enjoy every minute of it.
    • And to my dismay it doesn't include Xenix. Would have been nice to finally have an open source Microsoft product

      That's almost certainly why Xenix isn't in there. In the last days of SCO, they wanted to release the Xenix source code, but were held up in negotiations with Microsoft in trying to get the rights released.

      This is very cool indeed. These early UNIXes weren't at all feature-rich, compared to what we have now, but they were compact. Tight. Elegant. Worthy of inspection and study. And more accessible for that purpose because 5000 lines of code is more browsable than 500000. (Pulled both of those numbers out of goatse-guy's orifice.)

      • This may be a good time to post this Unix history timeline [wanadoo.fr]. Linux was inspired by Minix and written from scratch using no original AT&T Unix or BSD source code. Just about every "Unix" out there has something left in the source code from AT&T or BSD (sometimes with copyright notices too). Also, Unix is a trademark of The Open Group who acquired it from AT&T. You have to pay them to call your OS "Unix". Notice how the BSDs don't formally call themselves Unix?
    • so in other words.. useless..


      Not necessarily. The license on 32V also covers the encumbered 4.x BSD releases, for instance. aka the dawn of modern UNIX. And this is mainly for educational purposes, as the source has (as noted) already been available under a restrictive but free (cost) license for some time.

      seriously, in this day and age, how can the System V source NOT be released!


      Caldera still sells a product (UnixWare) based on System V. "How, in this day and age, can the Windows 95 source not be released?" Caldera makes money selling proprietary software. Its that simple.
    • SCO Open Server is 10x worse then Unixware. Don't even get me started :).

      A few notes:

      * No ELF shared libraries (COFF)
      * No loadable kernel modules (manually re-link the kernel for every new driver).
      * No kmalloc function for many kernel buffers; if you over-run a buffer you have to change the kernel header files, re-link and pray you don't over-run them again.
      * Many functions that should be in shared libraries are hacked to hell; for instance some NFS functions for "ls" are in ls itself rather then libc. GNU ls does not work with NFS directories on Open Server because of this.
      * They just implemented a dhcp client in Open Server about a year ago.

      [Necessary MS jibe] But hey, what can you expect from somthing that used to be a Microsoft product [Xenix].

      From what I could tell most of the SCO messiness came from a hacked merger of System V and System III into Open Server 5. What kills me about OpenServer is that it is STILL heavily used by the telco industry. A former company that I worked with looked at Linux but stuck with SCO Open Server because of "support" concerns.

      To the point:

      I'm just waiting for Caldera to Open-Source Open Server so that the whole computing industry can get a good laugh and Computer Science departments can gain a valuable teching tool as to what *NOT* to do in your OS :).

      I hate to say it, but I would prefer to be an MSCE then to ever touch Open Server again. Open Server is a complete shame to the name UNIX.

      I invite any Open Server fans out there to put in thier arguments for it -- I would love to hear anything that anyone has positive to say about it. Moreover, if anyone has a UNIX derivative that is *worse* then Open Server and is still sold today I would also love to hear about it. Frankly I don't think that's possible.
      • by Ethanol (176321) on Thursday January 24 2002, @01:52AM (#2893033)
        First off--you're dissing an operating system released by one company in 1993, because a different company has released the source to a different OS, which was written by still a third company, decades before the one you're complaining about. How, exactly, is this even remotely on-topic?

        That said, even though it isn't on-topic, I'd like to respond, for personal reasons: I'm one of the half-dozen engineers responsible for maintaining SCO OpenServer. (In point of fact, I'm the one responsible for that DHCP client you mentioned. BTW, if you think it's easy to maintain an entire OS distribution with a team that small, try it sometime.)

        I could post voluminous defenses of why OSr5 is the way it is, but won't bother. I'll just say this: Some of your complaints are quite valid. (Others aren't--where in the world did you get the idea we don't have ELF libraries?) But it can essentially all be chalked up to the fact that we're talking about a legacy OS from 1993 which is neither intended to be, nor sold as, a state-of-the-art kernel in 2002. (For that, you want OpenUNIX 8.)

        OSr5 is successful in the marketplace because it does what a lot of people need, does it well, does it extremely reliably, and does it in essentially the same way that it's done it for a decade (modulo those changes necessary to ensure that it runs well and takes advantage of the most current hardware)--which means no surprises for resellers and vertical-app vendors. There are fancier kernels nowadays, but nothing else on the market is as stable a platform, and for all its admitted outness-of-date, I'm very proud of it.

        To bring this back within hailing distance of the topic: I fervently hope that one day OSr5 will be open source too. I don't really expect it, unfortunately; not all of the code belongs to Caldera. Bits of the XENIX-compatibility code, as you noted, are licensed from Microsoft, and what are they odds they'd ever agree to open-source anything? But it would be very satisfying.
    • MOSIX [mosix.org] is clustering software that has run with Bell UNIX, BSD, and Linux, and originally ran on PDP/11's.