6 ms·

Xinu Is Not Unix

45 points by colinprince 7y ago

airocker 7y ago
Took this epic course. Getting virtual memory to work on x86 is still one of the most satisfying projects ever done! Thanks Dr Comer and everyone.
- bionsystem 7y ago
  How does it compare to os161 as a teaching OS ? What I really like about it is how fast it builds and runs and how comprehensive the course is with a decent amount of assignments.
  - airocker 7y ago
    I never did CS161. They look similar from the course page.
Koshkin 7y ago
Very little info on the website and Wikipedia about this OS.
- airocker 7y ago
  You could find more in the book. The OS was done mostly for teaching purposes. You could write the building blocks of the OS: virtual memory, context switch etc in an easier environment than Linux/UNIX.
tuckerpo 7y ago
Huh - my old RTOS professor from undergrad contributed a lot to Xinu and used to shill it to us in class. Didn't think I'd ever see it again.
- pg_is_a_butt 7y ago
  We focused on it in undergrad too. If I remember right the entire kernel was like 8 pages in the textbook, including commentary.
- airocker 7y ago
  I took another class from a professor who had never written an OS. It was decent but Xinu was much better.
- baylessj 7y ago
  Agreed, I was an EE at Purdue but still familiar with Xinu from CS clubs. Didn't expect to see it on HN, but a fun throwback!
dwheeler 7y ago
I'm sorry, but I don't see why anyone should waste a moment with a proprietary operating system with such limited use. If you need a simple educational operating system with a book, Minux is available and open source software. If you need a fully capable operating system kernel, Linux is available and is open source. There are also many other open source software systems, including the *BSDs, Zephyr, and so on. It takes time to learn the details of an operating system. I read parts of those books years ago, but I wouldn't waste any of my time with them today. Better to learn details of something you can use, or at least something you are legally allowed to change and share. If it is open source software, and my comments don't apply, but then they should make that much clearer on their front page.
- felipelemos 7y ago
  $ tar xzvf Xinu-code-Galileo.tar.gz $ cd Xinu-code-Galileo/ $ cat COPYRIGHT <<<begin COPYRIGHT>>> Portions of this software are covered by the following copyright: Copyright (c) 2012, 2015 Douglas E. Comer and CRC Press, Inc. All rights reserved. Redistribution and use in source and binary forms are permitted provided that this notice is preserved and that due credit is given to the copyright holders. The names of the copyright holders may not be used to endorse or promote products derived from this software without specific prior written permission. This software is provided `as is'' without express or implied warranty. The author assumes no liability for damages incidental or consequential, nor is the software warranted for correctness or suitability for any purpose. Portions of this software are documented in the book: Operating System Design -- The Xinu Approach, CRC Press, Boca Raton, FL, Linksys version 2012, Second Edition 2015. This software may not be sold or published in printed form without written permission from the copyright holders. <<<<end COPYRIGHT>>>
  - naniwaduni 7y ago
    It never ceases to astound me how many minor variants on 3-clause BSD retain clause 4 (the endorsement clause), despite not carrying the historical baggage of clause 3 (the advertising clause). It made sense for 4-clause BSD (and its unbulleted predecessor) as a qualifier on clause 3: although advertising materials must contain the acknowledgement, it should not be presented such that could be misconstrued as an endorsement. Even when striking clause 3, clause 4 remained inoffensive enough to not warrant making more than the minimal change. But for new work without that history, it's a total non sequitur.
austinl 7y ago
I took the course at Purdue that built on Xinu (CS 354, Operating Systems) — Xinu is really just used for teaching purposes. Doug Comer (the creator of Xinu) was my favorite professor — it was inspiring to hear from someone who was pretty close to the development of the Internet and TCP/IP in the 70s (https://en.wikipedia.org/wiki/Douglas_Comer https://en.wikipedia.org/wiki/Douglas_Comer).
DonHopkins 7y ago
Not to be confused with the Berkeley software company "Mt Xinu". (The operating system's name is a recursive acronym, while the company's name is a backwards spelling.) "We know UNIX TM backwards and forwards." -Mt Xinu https://en.wikipedia.org/wiki/MtXinu https://en.wikipedia.org/wiki/MtXinu Famous for the great posters they handed out at Usenix: "4.2 > V" BSD -vs- System V, X-Wing / Death Star Poster https://raw.githubusercontent.com/ashaferian/Drive/master/Mt.Xinu%20BSD%20Poster.png https://raw.githubusercontent.com/ashaferian/Drive/master/Mt... https://www.ericconrad.com/2008/12/ https://www.ericconrad.com/2008/12/ I love all the old telephone equipment in the explosion!

45 points by colinprince 7y ago

Took this epic course. Getting virtual memory to work on x86 is still one of the most satisfying projects ever done! Thanks Dr Comer and everyone.

bionsystem 7y ago
How does it compare to os161 as a teaching OS ? What I really like about it is how fast it builds and runs and how comprehensive the course is with a decent amount of assignments.
- airocker 7y ago
  I never did CS161. They look similar from the course page.

Koshkin 7y ago

Very little info on the website and Wikipedia about this OS.

airocker 7y ago
You could find more in the book. The OS was done mostly for teaching purposes. You could write the building blocks of the OS: virtual memory, context switch etc in an easier environment than Linux/UNIX.

tuckerpo 7y ago

Huh - my old RTOS professor from undergrad contributed a lot to Xinu and used to shill it to us in class. Didn't think I'd ever see it again.

pg_is_a_butt 7y ago
We focused on it in undergrad too. If I remember right the entire kernel was like 8 pages in the textbook, including commentary.
airocker 7y ago
I took another class from a professor who had never written an OS. It was decent but Xinu was much better.
baylessj 7y ago
Agreed, I was an EE at Purdue but still familiar with Xinu from CS clubs. Didn't expect to see it on HN, but a fun throwback!

dwheeler 7y ago

I'm sorry, but I don't see why anyone should waste a moment with a proprietary operating system with such limited use. If you need a simple educational operating system with a book, Minux is available and open source software. If you need a fully capable operating system kernel, Linux is available and is open source. There are also many other open source software systems, including the *BSDs, Zephyr, and so on. It takes time to learn the details of an operating system. I read parts of those books years ago, but I wouldn't waste any of my time with them today. Better to learn details of something you can use, or at least something you are legally allowed to change and share. If it is open source software, and my comments don't apply, but then they should make that much clearer on their front page.

felipelemos 7y ago
$ tar xzvf Xinu-code-Galileo.tar.gz $ cd Xinu-code-Galileo/ $ cat COPYRIGHT <<<begin COPYRIGHT>>> Portions of this software are covered by the following copyright: Copyright (c) 2012, 2015 Douglas E. Comer and CRC Press, Inc. All rights reserved. Redistribution and use in source and binary forms are permitted provided that this notice is preserved and that due credit is given to the copyright holders. The names of the copyright holders may not be used to endorse or promote products derived from this software without specific prior written permission. This software is provided `as is'' without express or implied warranty. The author assumes no liability for damages incidental or consequential, nor is the software warranted for correctness or suitability for any purpose. Portions of this software are documented in the book: Operating System Design -- The Xinu Approach, CRC Press, Boca Raton, FL, Linksys version 2012, Second Edition 2015. This software may not be sold or published in printed form without written permission from the copyright holders. <<<<end COPYRIGHT>>>
- naniwaduni 7y ago
  It never ceases to astound me how many minor variants on 3-clause BSD retain clause 4 (the endorsement clause), despite not carrying the historical baggage of clause 3 (the advertising clause). It made sense for 4-clause BSD (and its unbulleted predecessor) as a qualifier on clause 3: although advertising materials must contain the acknowledgement, it should not be presented such that could be misconstrued as an endorsement. Even when striking clause 3, clause 4 remained inoffensive enough to not warrant making more than the minimal change. But for new work without that history, it's a total non sequitur.

austinl 7y ago

I took the course at Purdue that built on Xinu (CS 354, Operating Systems) — Xinu is really just used for teaching purposes. Doug Comer (the creator of Xinu) was my favorite professor — it was inspiring to hear from someone who was pretty close to the development of the Internet and TCP/IP in the 70s (https://en.wikipedia.org/wiki/Douglas_Comer https://en.wikipedia.org/wiki/Douglas_Comer).

DonHopkins 7y ago

Not to be confused with the Berkeley software company "Mt Xinu". (The operating system's name is a recursive acronym, while the company's name is a backwards spelling.) "We know UNIX TM backwards and forwards." -Mt Xinu https://en.wikipedia.org/wiki/MtXinu https://en.wikipedia.org/wiki/MtXinu Famous for the great posters they handed out at Usenix: "4.2 > V" BSD -vs- System V, X-Wing / Death Star Poster https://raw.githubusercontent.com/ashaferian/Drive/master/Mt.Xinu%20BSD%20Poster.png https://raw.githubusercontent.com/ashaferian/Drive/master/Mt... https://www.ericconrad.com/2008/12/ https://www.ericconrad.com/2008/12/ I love all the old telephone equipment in the explosion!