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What do you think of Linux?
I would like to take this opportunity to thank Linus for producing it. Before there was Linux there was MINIX, which had a 40,000-person newsgroup, most of whom were sending me email every day. I was going crazy with the endless stream of new features people were sending me. I kept refusing them all because I wanted to keep MINIX small enough for my students to understand in one semester. My consistent refusal to add all these new features is what inspired Linus to write Linux. Both of us are now happy with the results. The only person who is perhaps not so happy is Bill Gates. I think this is a good thing.

Tanenbaums Amoeba is way ahead of the game then.

I guess the Vrije Universiteit Amsterdam is not doing so bad then. We have the MultiVLA (Dutch) project for visualisation of molecules etc. It involves 6 beamers and a big empty wall. (think DVD! ;) Students of the new interdisciplinary course Medical Natural Sciences get to use this stuff.

• Structure and Interpretation of Computer Programs
• Common Lisp HyperSpec
• Common Lisp the Language, 2. ed
• Common Lisp - A gentle Introduction to symbolic computation
• The Scheme Programming language, 2. ed
• Reflections on trusting trust
• Lisp: Good News, Bad News. How to Win Big
• John McCarthy's homepage
• Dennis Ritchie's homepage
• Various classic papers it's a shame ACM never bothered to continue adding to
• Another list of classic papers (this time related mostly to programming language design)
• GTK-Gnome Application Development (not a classic, though, as the field is too young)
• KDE 2.0 Development (not a classic though, as the field is too young)
• Eric Weissteins Mathworld
• Compilers and compiler generators - an introduction with C++ (although I'm not too sure if it deserves being called a classic...)
• Parsing techniques - A practical guide
• Art of assembly language programming (never was a dead tree, but good anyway)
• Paul Carters 386 assembly book (same comment as above)
• An Introduction to Scheme and its Implementation (see comment above)
• How to design programs - An introduction to programming and computing (not a classic, yet!)
• The Gutenberg archives contains much non-copyrighted classic fiction in ASCII format
• Sacred texts has copies of or links to many religious text for various major (or minor) religions

Also, it wasn't a mailing list, it was the comp.os.minix newsgroup. (I was a frequent Minix contributor from around 1988 until mid-1990. I lost access to Usenet before Linus showed up.)

I've heard that the best openings to play against computers are the ones that are positional in nature instead of tactical. That is, computers are clumsy when it comes to general assessments of the board, whereas they are better at direct attack and defense. So human chess adepts generally avoid these tactical situations. Additionally, when chess adepts play computers, they tend to deviate from well-known or standard opening lines to get the computer "out of book" as soon as possible.

I wonder, though, if there are any particular opening strategies when computers play each other, as opposed to human v computer? It seems to me that chess programs with good opening books would almost never fall into well-documented opening traps like the one that claimed Kasparov in his losing match against Deeper Blue. Do computers stick to the tried and true main lines when playing against each other, or would employing opening "novelties" work well?

GNU was never really finished -- if the HURD kernel is ever final, it will be the last piece. But when you clone a highly modular system like Unix, you end up with a lot of bits and pieces that are useful as separate products. So GNU's libraries, utilities, and (most of all) compilers developed a life all their own. Personally, I've never been impressed with the quality of GNU software, but it does have functionality that closed-source venders always seem to overlook. So GNU products are almost ubiquitous in the Unix world, and have a fair following on other platforms.

So time passes. It's 1991. People are still waiting for an alternative to paying fees to whoever owns Unix. (It changed hands several times.) One cheap alternative is minix a sort of toy Unix that sells for $100. But a certain Finnish grad student can't even afford even that much. He decides to write his own Unix kernel. He gives away copies to a few friends. Who give it to a few friends... All of a suddent, lots of people are using this kernel to run all the GNU software. Which means there's now a free alternative to Unix! Project GNU has succeeded! It's just not complete.

And since the final piece of the puzzle is a non-GNU program, that program ends up being the name for the whole conglomeration! Much to the disgust of Stallman. Maybe he's just testy because Torvalds doesn't like EMACS.

This isn't a troll, I'm just trying to get a handle on why exactly the HURD exists.

1) Is it because its all GPL?

2) Is it because its a microkernel?

3) Maybe a new, improved microkernel? Not MACH.

4) Security?

5) Performance? Yea right.

6) Ease of use? Isn't that up to KDE and GNOME?

7) Translators, Namespace unification, RPC? Been there, done that.

So, exactly why does HURD exist? What does it bring to the table that hasn't been seen dozens of times before? (Besides allowing non-root users to mount partitions!)

This isn't a troll, I'm just trying to get a handle on why exactly the HURD exists.

1) Is it because its all GPL?

2) Is it because its a microkernel?

3) Maybe a new, improved microkernel? Not MACH.

4) Security?

5) Performance? Yea right.

6) Ease of use? Isn't that up to KDE and GNOME?

7) Translators, Namespace unification, RPC? Been there, done that.

So, exactly why does HURD exist? What does it bring to the table that hasn't been seen dozens of times before? (Besides allowing non-root users to mount partitions!)

Here are just a few of the tools that are considered traditionally in UNIX/Linux/BSD territory that are available for Win32. In all actuality, there's enough out there to get as much of Linux running on Win32 as Win32 running under WINE.
XFree86: http://sources.redhat.com/cygwin/xfree/
KDE: http://kde-cygwin.sourceforge.net/
GTK/PHP/Libglade: http://gtk.php.net/download.php

Apache: http://www.apache.org
PHP: http://www.php.net
PHPTriad: http://www.phpgeek.com
Perl: http://www.activestate.com
Ruby: http://www.pragmaticprogrammer.com/ruby/downloads/ ruby-install.html
Python: http://www.python.org/download/download_windows.ht ml
TCL/TK: http://www.pconline.com/%7Eerc/tclwin.htm

MySQL: http://www.mysql.com
MySQL ODBC: http://www.mysql.com/downloads/api-myodbc.html
PostgreSQL: Included in cygwin (only works on NT)

ATT's U/WIN* Unix for Windows: http://www.research.att.com/sw/tools/uwin/
Cygwin: http://sourceware.cygnus.com/cygwin/
DJGPP: http://www.delorie.com/djgpp/
Native UNIX command-line binaries: http://www.wzw.tu-muenchen.de/~syring/win32/UnxUti ls.html

vi: http://www.cs.vu.nl/~tmgil/vi.html
Emacs: http://www.cs.washington.edu/homes/voelker/ntemacs .html
OpenOffice: http://www.openoffice.org

Mozilla: http://www.mozilla.org
GIMP: http://user.sgic.fi/~tml/gimp/win32/

List of GNU software for Windows: http://www.gnusoftware.com/
And so on . . .

There's a list over at DMOZ.org of a lot of this.

OS research has been pursueing these goals for years. There's nothing there that's really very interesting or new. It sounds like they've just browsed the web for a little while and summarized what the various projects are striving for.

One project that's come pretty far is Mosix (I think they're planning to integrate bits into Linux 2.5, but I'm not sure). Then of course there's Plan 9 and Inferno from the fine folks who brought you Unix. And lets not forget Tanenbaum's Amoeba.

Even if this guy should beat the computer, that should not lead anyone to having illusions about the future. Eventually, computer chess superiority will be a fact. Even though the program running on Deep Blue could beat Kasparov, that day is not today. The very fact that we are unsure whether Validimir Kramnik or the computer will win clearly proves this.

One reason that computers inevitably will beat us humans is that each year, computers get exponentially faster, which means the chess programs can search linearly deeper in the game search tree. It's simply a matter of waiting untill they are unbeatable.

However, that wait might be very long, but to top things over, algorithms are improving too. Some have thought in the past that our game-tree search algorithms were pretty close to optimal, but for example some of Aske Plaat's research clearly shows that this is far from the case, and that the old predictions about optimal performance was based on too simple and fundamentally unsound principles. Substantial improvements can be made. (not that I have anything to do with him. I don't know him and live in another country)

Even more important is the fact that we need not search the full search tree (indeed Deep Blue did not, using instead something called singular extensions). Rather, if we can make a heuristic that tells us which parts of the search tree are "interesting" we can skip the rest and only concentrate on those areas. In this way, computer chess is becoming a little more like human chess (though not much). The point is, as those "this part of the tree is interesting" heuristics get better, so will computer chess programs get better.

In short, the future of computer chess is bright, and we might have only seen the tip of the iceberg. Human superiority or even something resembling it simply will not last. Chess will neither be the first nor the last game where computers will always beat a human.

I'd watch just to find out.

Amoeba which is now freely available for anybody to use.

If you guys are interested in solvable games, then you should have a look at this thesis It describes games such as go-moku , connect four, othello and checkers. I think that they use partly brute force and partly clever analysis of the games.

Hey! Don't complain! You've never tried Minix on an old Mac. Now that was bad! A/UX was a godsend to the Mac compared to Minix.

With XP being somewhat controversial it was a good topic for me to write a paper about it. The paper was submitted to pass a software engineering course at my college.

In the paper I tried answering where XP is all about, if it's new and if it's useful.
If you have a minute, check it out and I would really be appreciative of receiving comments.

The problem is not whether machines can think, but whether men do
BF Skinner

very friendly way of specifying firewall rules, regardless of what the underpinnings are (ipchains, iptables)

If anything, the comment could have been re-phrased better as Linus+Minix+(gnu tools)=Linux, but (apologies to Andy Tannebaum) I don't believe Linus ever used any of the minix source on his development path, since he says just that in the initial announcement of his plans.

aem

If anything, the comment could have been re-phrased better as Linus+Minix+(gnu tools)=Linux, but (apologies to Andy Tannebaum) I don't believe Linus ever used any of the minix source on his development path, since he says just that in the initial announcement of his plans.

aem

If anything, the comment could have been re-phrased better as Linus+Minix+(gnu tools)=Linux, but (apologies to Andy Tannebaum) I don't believe Linus ever used any of the minix source on his development path, since he says just that in the initial announcement of his plans.

aem

At doc.ic.ac.uk, the second year students get a lab exercise to modify Minix (which is, of course, a microkernel design). Last year it was adding a new kernel task for debugging and a user process which sends messages to this task to step through programs and set breakpoints. The number of layers a system call goes through is rather scary. Still, it's no worse than on Linux or any other complex OS, just more explicit.

There's a really nice Operating System textbook written by Andrew Tannenbaum that is written around an OS kernel that's form fitted for student use.

You may want to look at Structured Computer Organization from Andrew S. Tanenbaum (Creator of MINIX). It covers the changes of programming languages, instruction set, computer architecture, milestones in development of digital computers (Vaccuum Tubes to Transistors to VLSI), Moore's Law, Pentium , UltraSPARC, picoJava, storage, RAM, .... to how to design your own CPU.

You may find it too advance to under the whole designing CPU chapters, but it sure gives you a general idea of the history of computer in its introduction chapters.

You can also try the Computer History Association of California, and the Computer Industry History page from Electronic Software Publishing Corp.

Others have mentioned MkLinux, which is a version of Linux which runs on top of the Mach microkernel. By modern standards, Mach isn't so "micro". On my Hurd partition, the gnumach executable weighs in at 726kb compressed, and about 1.6Mb uncompressed. Compare with ntoskrnl.exe, which is 907kb on NT 4.0 enterprise server. Both of these are comparable with the size of an average linux or BSD monolithic kernel, which sit around the megabyte mark uncompressed.

The QNX kernel, on the other hand, is something like 8kb in size, which fits in the cache of a 486. Even the BeOS kernel is only something like 78kb compressed. Not that size is the only concern (so my wife keeps telling me), but in general, the less code that runs in the kernel, the easier it is to say something about how secure it is. Also the easier it is to change things while the system is running.

I hate to sound like Andrew Tanenbaum, but MkLinux and the Hurd are now obsolete too. Mach belongs to the old school of microkernels which were popular 10-15 years ago, but with the benefit of hindsight, we know better. Nowadays, for example, we know that you don't even need to do VM swapping inside the kernel.

There are some projects of note which may result in a product which is cleaner and better designed than Linux. Here are some suggestions:

• chaos, which has a very clean, pragmatic design without sacrificing its microkernel philosophy
• VSTa, which is loosely based on Plan9 and QNX
• There's one out there somewhere which is an Open Source re-implementation of L4. Can anyone provide a link?
• Or you could always roll your own...

Amoeba is freely available with an Xfree86-style license. It looks like a very nice system and you can read more from the source

• Mach was the "granddaddy" of distributed OS work, with most of the recent efforts going into GNU Hurd.
• There's Mosix that builds a NOW atop Linux
• The MIT Parallel and Distributed OS Group should be mentioned; efforts include the Exokernel
• Plan 9 has an interesting model for splitting work across "compute servers" and "file servers" and "display servers."
• Distributed Operating Systems lists lots of them...
• Sun's Spring was the basis for much of what is in CORBA;
• Sprite provided a Unix-like distributed OS that provided much of what is being used now to build journalling filesystems
• Amoeba was Tanembaum's successor to Minix; note that Python was one of the side-effects of the Amoeba project...

Each has some somewhat different insights to bring to the table; there is no unambiguous way of saying "this is all vastly superior."

You might want to check out "Distributed Operating Systems: Concepts and Design" by Pradeep Sinha.

It talks about Amoeba, the V-System (I couldn't find a good web page), and Chorus.

It's a textbook so it also has a lot of theory about general distributed OS's.

• Amoeba, one of the first, most mature, and most well-known distributed OS projects.
  
  
• Guide, a distributed "operating environment" that runs on top of *NIX.
  
  
• Plan 9, from Lucent, has some distributed components
  
  

I agree. Software has much changed ; scripting languages and Java, are a clean proof. They even brought some of older language research into commonly used systems.
The extension of Pike's question would be now "is current language research relevant?", but I'm not a language researcher, so I suspect I'll have to wait 10 years to see novelties appearing (or not).

I also imagine that a paper describing how to scale Gnutella to the point where it would still be useful with two orders of magnitude more users would also be "research material."

Probably. Probably such a paper had already been written long ago :-) A recent candidate might be in Globe

There is a very interesting FAQ written by Andrew Tanenbaum on Tanenbaum's site. Amongst other answers and questions, I found this ones:

What do you think of Linux?
I have never used it. People tell me that if you like lots of bells and whistles, it is a nice system. I would like to take this opportunity to thank Linus for producing it. Before there was Linux there was MINIX, which had a 40,000-person newsgroup, most of whom were sending me email every day. I was going crazy with the endless stream of new features people were sending me. I kept refusing them all because I wanted to keep MINIX small enough for my students to understand in one semester. My consistent refusal to add all these new features is what inspired Linus to write Linux. Both of us are now happy with the results. The only person who is perhaps not so happy is Bill Gates.

What's wrong with LaTeX?
Nothing, but real authors use troff.

What do you think of MS-DOS?
It is better than Windows. At least it has a command line interface, albeit a pretty feeble one.

Ehm... I guess Tanenbaum likes simplicity a bit too much. I mean, he is convinced that a GUI can not make any improvement at all. For example, I use Lyx for making my thesis and I am convinced it is able to produce real quality material. Yes, it's a graphical WYSIWYM frontend to LaTeX. How can anyone be convinced Lyx isn't good because of that?

If you think Plan 9 is "odd", check out Amoeba, from the father of MINIX. Amoeba is a "true" distributed operating system, much more so than Plan 9. (Also, the source to Amoeba is freely available, whereas you have to pay 250 bucks to get the source to Plan 9.)

There have been various attempts at distributed operating systems in the past; some, such as amoeba and plan 9 are actually usable, to a certain point. Unix is here to stay--it's not going to disappear until someone maxes the next "big step" in computing, and maybe not even then. There are a number of projects out there that are quite interesting. On the one hand, you have OSes like QNX which were designed to be entirely distributable (for lack of a better word) from the ground up. One of K&R (I can't remember which one) once said that one of the places where unix failed to take the "everything is a file" concept to its logical conclusion was networking. (In plan9, pretty much everything, including networked stuff is a file). I don't think that distributed OSes will kill unix, but that unix will eventually become a distributed OS. For example, GNU/HURD (which is getting along very nicely BTW), while not an attempt at a distributed OS, is designed in such a way that it will be easy to transform into a distributed system.

I'm upgrading my A3000 to potato this weekend, whoohoo! For more info on these UNIX's, check out:

• MINIX Information Sheet (the Amiga disk images are here).
• Installing Debian GNU/Linux 2.1 For Motorola 680x0
• NetBSD/amiga news
• OpenBSD/amiga info

I'm upgrading my A3000 to potato this weekend, whoohoo! For more info on these UNIX's, check out:

• MINIX Information Sheet (the Amiga disk images are here).
• Installing Debian GNU/Linux 2.1 For Motorola 680x0
• NetBSD/amiga news
• OpenBSD/amiga info

Why would anyone use vi instead of xedit (or another easy to use editor)? We're just editing text files after all --so why *not* use something easy to use and just ditch vi?

vi is default visual editor under Unix, and is therefore shipped with all recent version of Unix. (Recent being defined as post 1984 or so.) This means that whenever you run across a machine that is running a Unix of some sort, you will know that you have a powerful editor at your finger tips. Why else? vi is a powerful editor. Also, once you know vi, you can edit files really quickly, as it is extremely economical with the keystrokes. Due to its different modes for inserting and issuing commands, it is much faster than most non-mode based editors. It is also a very small editor. (The version on my machine is 200k) Also, it can do almost anything, as long as you know how to get it to do what you want.

Is Inferno just a Java type thing, or is it possible to boot inferno - no other OS involved?

What about plan-9, or amoeba - can someone clarify?

(well i know amoeba is independent - hey look at that, Tanenbaum opened up the license on Amoeba, now it is free to more than Big Universities. X-Free style license.
http://www.cs.vu.nl/~ast/ )

Is Inferno just a Java type thing, or is it possible to boot inferno - no other OS involved?

What about plan-9, or amoeba - can someone?

(well i know amoeba is independent - hey look at that Tanenbaum opened up the license on Amoeba, now it is free to more than Big Universities
http://www.cs.vu.nl/~ast/

Hmmm. I sent private email to Sengan about the domain name squabble. I did not expect to have my name broadcast so prominently, when I post followup comments to slashdot, I just call myself trb. I am not the Minix guy, and neither of our names is spelled Tannebaum. I'm Andrew Tannenbaum, I've been hacking UNIX for over 20 years, I was more active on the net/usenet before it got so crowded. The Minix guy is Andrew S. Tanenbaum. We both worked at Bell Labs at the same time around 1980, and the mailroom found it somewhat confusing. If want to be ambiguous in a different way, call me trb.