[kalonji]

hello all. i'm not much of a computer expert like the majority of the people on this board.

with that said, i'd like for someone to explain to me what the heck a UNIX based OS does. i myself have only been a mac user for half a year, but even after the first 30 minutes of
using os x, i realized that macs are vastly superior to pcs in every way. the OS was the beacon of light that opened my eyes.

can someone give me a rundown of why and how a UNIX based os is so good?

what was os9 and previous apple os's based on?

what about microsoft? particularly longhorn? is that going to be a unix based os?

is linux another testament to the benefits of a unix os?

and throw in any other tidbits of computer enlightenment my way.

i tried looking for an online faq but i couldn't find a definitive faq based on what i was looking for.

gratzias

[Maflynn]

I'll throw my two cents in.
Unix is an operating system developed by AT&T (bell labs) at some point they gave (sold?) the rights away one of which was berkerly univ. They developed their flavor and called it BSD. System V is a AT&T flavor that Sun uses.

Unix is a mature os that has been around quite a while which means its pretty stable has strong networking and mutliprocessing capabilities .

OS9 and previousversions were an Apple development.

Longhorn is just the next iteration of windows which does not ahve any unix code its basis is Windows NT.

Mike

[kalonji]

thanks. so i assume unix is an operating system that's similar to MS DOS? nothing but text and lines?

so mac osx is in effect unix with a gui slapped on top of it?

[kman42]

Originally posted by kalonji:
thanks. so i assume unix is an operating system that's similar to MS DOS? nothing but text and lines?

so mac osx is in effect unix with a gui slapped on top of it?

Sort of. There is a 'text and line' way to interact with the OS, called the command line interface or CLI. The real OS is actually deeper down and the same is true for Windows, Linux and every other OS. The thing you interact with isn't REALLY the OS, but an interface, be it graphical or text based, which then does the interacting with the OS. It's just that for many years, the CLI was the only way to interact with UNIX and it is still an extremely powerful way, so the popular impression is that it is a 'text and line' based OS. In fact, there are many graphical interfaces to UNIX, most using the X Windowing system (or X11), which is also available for OSX (BTW, this gives us access to thousands of very powerful UNIX apps).

Windows also has a CLI, it's just not as robust as most flavors of UNIX shells (a shell is another name for the CLI).

It's not really fair to say that OSX is just a graphical interface slapped on top of UNIX. It's true that the underpinnings of OSX are based in UNIX, but the interface is certainly not slapped on. Apple doesn't very often slap on anything. It is actually one of the most elegant user interfaces (if not the most elegant) out there and from the looks of Panther it will be even more so.

If you are really interested in learning more about the CLI (and it is worth while if you are interested), try osqfaq . Look at the FAQ and the tutorials on the left hand side. That will get you started.

kman

[depolitic]

Strictly speaking UNIX or Unix is not an operating system. It is rather a concept of what an operating system is and how it should work. UNIX comes in assorted flavors, of which OS X is just such a UNIX flavor. Other UNIX operating systems of fame are Sun Solaries, HP UX, and FreeBSD, Apples UNIX is called Darwin. and is related to FreeBSD UNIX, which is one of the oldest and most stable form of UNIX.

UNIX was originally created in 1970 at Bell Labs (I think), and was rewritten in the C programming language in 1971. The programming language C was largely developed for writing the UNIX OS. Most UNIX can trace their heritage to that original UNIX flavor from Bell Labs.

Linux is NOT a UNIX operating system, it is what is termed UNIX like. It was created by Linus Thorwalsin (I am sure that is not spelled correctly) in 1990 while Linux was at University in Norway (I think). Linux is able of running most of if not all UNIX applications, however the way Linux functions internally is different from most UNIX OS flavors. However most people tend to think of Linux and UNIX as begin one and the same.

Microsoft and its OS current and future has nothing to do with UNIX. Microsoft uses its own proprietary NT OS. Windows 2000, Windows XP, and Longhorn, are all NT based.

In most peoples opinions NT is the poor, very poor distant cousin to UNIX. Microsoft will never adopt UNIX at the core at its OS because UNIX by nature if mostly nowadays open sourced and if not it is not the workings of UNIX is well understood. This is something Microsoft will never be able to live with, as it loved closed proprietary systems. Microsoft has in the past plaid with UNIX, I believe about 20 years ago MS tried to get a version of UNIX to run, but it was a huge disaster.

What makes UNIX what it is. That I can not say with confidence however most UNIX's have these points in common:

1- Multi user
2- Multitasking
3- easily ported to other Hardware configurations
4- True Protected memory
5- Most software that will run on UNIX flavor (a) will run on UNIX flavors (b-c-d) etc. With little modifications.
6- Permission Read-Write-Execute

As for Apples OS 9, that is just ancient history, it was like a family member that we loved dearly but had grown to old, and suffered to much of the afflictions of age, that most were glad to see it pass into history. OS 9 was Apples own proprietary OS but which lacked all the hallmarks of a modern OS. OS 9 has no relation to OS X (A UNIX flavor), Apple just used the naming convention going, but neither OS's have anything in common beyond sharing similar names.

[rantweasel]

Originally posted by kalonji:
can someone give me a rundown of why and how a UNIX based os is so good?

Operating systems are like shoes - what fits you might not fit me, what works for running track might not work for tap dancing, etc. A UNIX basis for an OS is not a guarantee that it will be perfect, or that it will do what you want, or be the right tool for the job. Having said that, I find OS X, Solaris, and OpenBSD to be the right toolbox for me. The quickie reasons:

• simplicity - once you learn the concepts, unix is fairly simple and elegant - everything is a file, most things can be done using a combination of small, single purpose tools, etc
• maturity - with over 30 years to rework and rethink the basic approach, modern unixes are fairly well planned and most of the awkwardness has been smoothed out
• flexibility - you can use one tool to do lots of things, and you can use lots of different tools to do the same task
• stability - the flexibility and the maturity lend themselves to an OS that's fairly hard to knock over

Now, there are other approached that work better for some things, or are better planned, but those are just things I find work for me.

For a fairly comprehensive history of UNIX and related operating systems, see this chart. There are two basic schools of unix-y OS - Sys V-ish, and BSD-ish, depending on which of the two the OS is more influenced by. OS X is a BSD-based system (via FreeBSD), whereas A/UX was a more Sys V-ish system.

Unix based OSes can have any sort of interface, such as Aqua, Sun's CDE, the X11 window system, etc.

what was os9 and previous apple os's based on?

OS 9 was based on OS 8, which was based on System 7, etc, all the way back to the 128k Mac running System 1. It was conceptually based on work done at Xerox PARC, but it was written by Apple.

is linux another testament to the benefits of a unix os?

Linux is a from-scratch effort to write a unix-like OS. Compare it to Solaris, Sys V, or one of the BSDs and judge it for yourself.

mathias

[kalonji]

gratzias this is great info.

[depolitic]

UNIX consists of layers, at the core is the Kernel, the soul of UNIX, on top of the Kernel rests the Shell, This is just a simple application layer that allows you to issue commands directly into the UNIX kernel. (Look for /Applications/Utlities/Terminal) application to access the Shell in OSX. On top of the shell most UNIX's have a Window Manager, most UNIX's use XWindows or the X11 window manager, Apple however by default gives you Aqua Window Manager which is a lot more attractive then X11. But Apple also supplies you with X11 as many UNIX style application interfaces are X11 specific.

[depolitic]

I recommend - Learning the UNIX Operating System O'Reilly by Jerry Peek, Grace Todino and John Strang.

If you wish to become more comfortable with your friend UNIX.

[malvolio]

Originally posted by depolitic:
Linux is NOT a UNIX operating system, it is what is termed UNIX like. It was created by Linus Thorwalsin (I am sure that is not spelled correctly) in 1990 while Linux was at University in Norway (I think).

A small correction: Linux was written by Linus Torvalds, a Finn, while he was a 21-year-old student at Helsinki University (Helsinki is the capital of Finland).

[depolitic]

Thanks malvolio.

[kalonji]

COOL. i think i'm learning something about unix.

but about microsoft. obviously the most widely used os in the world, but we all know that it's very crappy one way or the other.

getting into the nitty gritty..what is it about microsoft that is so horrible? what is this talk about registries? and is it easier for programmers to write software for NT based os's or UNIX based os's?

thanks again

[depolitic]

the most widely used os in the world

That is a loaded statement. Windows may be most popular on the Desktop. However UNIX, and Linux, are the dominant OS's for Enterprise, Scientific, Research, Servers, Fortune 500 companies.

Windows gained its position of dominant desktop OS by intimidation, threats of violence and retributions to is friends and enemies alike. That is why Microsoft has so few true friends. Outside of the hordes of hangers on who suckle at the Microsoft teat, all hoping that they do not fall victim to the monolith.

However Windows has been more GUI focused
then UNIX and UNIX tends to have a higher learning curve. This is however lo longer true with Mac OS X with its UNIX core but with a effective Aqua GUI (Window Manager).

Developers tend to write more for Windows not because it is easer, rather many claim that it is far harder to be a Windows developer then it is to be a UNIX developer. The driving force to develop for Windows is market share, even if your application sucks, their are just so many Windows users out-there that you will still make a profit.

Microsoft has also traditionally courted developers very well. Giving them easy to use tools like Visual Studio, in combination with simple yet effective languages like VB. Microsoft is keenly aware that developers form the bases for your OS with out applications your OS will shrivel and die.

That is why Apple gives away its developer tools, which are in most peoples opinions not as good as Microsoft Visual Studio, however they are very expressive for free tools. Apple also offers a very powerful language frameworks for developers to use in the shape of Cocoa, Java, and Carbon. Apples also gives supports for C and C++ languages. that is why the number of Developers on the Macintosh has gone from something like 10 000 to over 300 000 in the space of three years, the same amount of time Apple has been promoting OS X. Which has attracted huge numbers of UNIX, Linux, Mac OS 9 developers and a fair share of Windows developers. Added to this their has been a ground swell of amateur developers on Mac OS X developing a huge array of free and shareware applications.

You must however remember that UNIX and Windows markets have traditionally been very different in their demographics. Windows is focused on Business productive and office applications. UNIX, however is more focus on Server, database and enterprise based applications.

This division of labour however is no longer so true with OS X, as it is well able to run both business productive applications and enterprise applications all from the single OS and hardware. The best of both worlds.

[Nonsuch]

Originally posted by kalonji:
getting into the nitty gritty..what is it about microsoft that is so horrible? what is this talk about registries? and is it easier for programmers to write software for NT based os's or UNIX based os's?

thanks again

I'm not a developer, but it's a slow evening and few are pitching in, so I'll have a go.

The not-too-technical definition of the Windows Registry is that it's a database component that records and manages the program files that reside on the operating system. The trouble with the Registry is that it's very prone to a) bloating, as change after change is added, and b) data corruption. This results in the characteristic gradual degradation of performance in Windows that some longtime users call "Windows flu." The simple solution to this is to wipe the OS and reinstall it, something that Windows pros were accustomed to doing religiously a few times a year.

I understand that Microsoft has gone some way to relieving the Registry's more troubling characteristics, but I can't tell you much more. We have several savvy Windows users here who could advise (and probably correct me in the process).

[The_FrO]

Ok, I have to throw my 2 cents into this topic here.

First of all, Mac OS X is *NOT* UNIX. It's based on BSD. Although BSD has the same codebase as AT&T UNIX did, they are completely different entities. At this point, MacOS X is NOT a UNIX operating system, because Apple hasn't gotten the certification from The Open Group (who owns the copyright to the UNIX name). There's actually a big legal spat about this going on right now.

The high UNIX learning curve is still there with MacOS X, it's just hidden from those who don't want to see it. You could open up Terminal (like I do every day), and still have to learn many of the same *NIX commands and programs that are on Linux or BSD machines.

yes, as of late Microsoft has been using some dirty tactics to keep market share. But in the beginning, it was their innovation that really gained them market share. the NT line of operating systems were actually quite advanced for their time, and included many basic features that were absent in most desktop OS's (good memory management, multithreading and multiprocessing, etc). Whether you want to admit it or not, Microsoft has come a long way from Windows 1.0 to XP (or even from NT 3.51 to XP).

It is true about the market share. But, honestly, it's all a matter of preference. for example, I've heard that WinSock programming is very similar to the BSD sockets that are used in most UNIX Operating Systems (I don't know winsock, but I do know BSD).

As for the business vs servers thing, traditionally the NT line of OS's has been the staple of the business desktops, while UNIX and UNIX-like OS's have been servers. This is changing, as Microsoft has been making inroads into the server market, and Linux has been making it easier to use a Unix-like desktop. the lines are blurry right now.

I disagree that Apple is positioned themselves to be an enterprise solution, nor do I think that any IT manager in their right mind would buy an Xserve for some large-scale operation. x86 PCs still have better choices for OS's (choosing Windows NT, Netware, Linux/BSD depending on need), and still have a higher price-performance ratio (for current hardware).

[DeathMan]

Originally posted by The_FrO:

First of all, Mac OS X is *NOT* UNIX.

For all intents and purposes (intensive purposes) Mac OS X is a Unix operation system. You sound like the Open Group. Unix is a generic umbrella type word now that means - Unix Based / Linux Based / BSD Based. Its all the same. Why do think there has been so much hoopla in the past about who stole code from whom?

About why MS sucks so badly? Its because they can't leave people behind. Apple leaves people behind, and doesn't shed a tear. They don't care. They are moving forward, always forward. MS has enterprise customers that they can't afford to lose through a failure to be backward compatible.

I think Windows main problem is that they have had to patch and patch and patch. They've kind of gotten around this to some degree since XP, since *old* apps sort of run in their own virtual old machine, but the backwards compatibilty has caused a lot of bloat. QDOS stands for quick and dirty operating system. It was bought by Microsoft in the olden days, and renamed MSDOS (microsoft disk operating system - creative eh?)

Anyway, up until XP most of you computer users had to be stuck with the quick and dirty operating system at the core. I am of the opinion that the MacOS was better than the QDOS based MS Systems. NT 4.0, Win2K and finally XP had the stability the MacOS lacked. Lucky for us we had OS X on the way.

So apple has chopped out a lot of the deadwood, and MS has figure a way through it, so things are a lot better than they used to be.

I can't say I care much for the Windows GUI, though. everything seems burried, and hidden. Especially network settings. Well, anything really.

things have definately gotten better on all sides. This is why competition is good.

[Phoenix1701]

Originally posted by The_FrO:
... I've heard that WinSock programming is very similar to the BSD sockets that are used in most UNIX Operating Systems ...

That might have something to do with the fact that Microsoft lifted a great deal of the BSD network stack for Windows NT 4. It seems to me like Microsoft has been engaging in FUD (fear, uncertainty, and doubt) tactics since the very beginning, so I don't know if I buy the idea of Microsoft innovation (in fact, whenever a Microsoft spokesperson uses the word "innovation" in a sentence, you can confidently expect the rest of that sentence to be completely devoid of any logic or truth. Do a google search; you'll be amused).
Anyway, it should also be noted that you can, indeed, run Linux on your XServe if, for some reason, you decide Mac OS X Server isn't what you want. About all you lose is Solaris and WinNT. The_FrO is correct, however, about the price/performance ratio at present: what you pay for in Macs is, and has always been, the better OS and the proprietary hardware.

[Sophus]

Originally posted by The_FrO:

... yes, as of late Microsoft has been using some dirty tactics to keep market share. But in the beginning, it was their innovation that really gained them market share. the NT line of operating systems were actually quite advanced for their time, and included many basic features that were absent in most desktop OS's (good memory management, multithreading and multiprocessing, etc). Whether you want to admit it or not, Microsoft has come a long way from Windows 1.0 to XP (or even from NT 3.51 to XP). ...

It is not just the fact that Microsoft was "innovative" that led to their huge market share. It is also the fact that the unix-based solutions and hardware of that time was extremely expensive and totally unavailable to ordinary users! Microsoft won their posistion by offering a (relatively speaking) cheap and easy-to-use solution for home and desktop users just when home computing took off. In those days, and to some extent still, Microsoft products are considered an inferior and cheap and somewhat primitive and flawed solution. However, with the close ties needed to accomodate all the newborn desktop users (using MS office for more than a decade now) from the server side, cheap hardware and the fact that a generation of everyday users and IT-professionals) is raised using MS windows on their home computer, Micro$oft has also positioned themeselves in the low, mid and high levels of the server market. Still unix is the real thing. The reputation of MS products in terms of reliability, flexibility and trustworthiness is tattered, and the reputation is well deserved.

I am a former IT-professional and have worked with both Unix, Linux and Windows for quite a few years. My opinion is best expressed with a saying of my brother "a million flies can't be wrong, dung tastes good!". With a shitty os at its base with nice topping to go, as does windows I presume.

Sophus

[Gee4orce]

I did hear that Windows NT - and thus Windows XP - is based on VMS. This is quite ironic because VMS was a minicomputer operating system and a competitor to Unix. It had a command line interface like Unix, but although it was easier to learn (more 'engligh like' commands), it was nowhere near as flexible. Funny, then, that we now have Unix based Macs and VMS based PCs !

[stew]

Originally posted by Sophus:
My opinion is best expressed with a saying of my brother "a million flies can't be wrong, dung tastes good!".

Acutally, dung is good food for you if you happen to be a fly.

[wadesworld]

Giving them easy to use tools like Visual Studio,

You think MS gives away MS Studio? No way. It's quite expensive.

But you're correct - the reason most people develop for Windows is marketshare. A good product will sell hundreds of thousands of more units than on the Mac.

Of course there's more competition, marketing and tech support costs are higher, etc. That's why despite the lower number of units moved, many developers who are smart about it, find there's still enough money in the Mac market to make it worthwile.

Those who aren't smart about it, fail and then blame their failure on the Mac market.

Wade

[Drizzt]

Some of you guys need to learn a bit of history about operating systems..

BSD is "based" on AT&T Unix about as much as Window's GUI is "based" on MacOS. They rewrote the hole thing up for legal reasons (and fun I guess)..

What makes an operating system a Unix is it's POSIX compilance, which makes Windows 2000 a Unix-like OS (it's POSIX-1). It doesn't have to have a shell, it doesn't have to have a GUI, it doesn't have to to look like anything else in the world at all!

MacOS X is Posix-1 also and has been verified by 'The Open Group'.. it still has ways to go though.

[Sophus]

Originally posted by stew:
Acutally, dung is good food for you if you happen to be a fly.

No doubt about that, but I am not a fly in a swarm of a million flies. I have a taste for the good quality stuff, hence OSX is my preferred OS for personal use as a near perfect marriage between unix/linux and the good qualities of a modern desktop system. I will leave windows to the flies...

Sophus

[tooki]

P.S. The Windows NT kernel (and CLI) is in fact a clone of Digital Equipment Corp.'s (now part of HP-Compaq) VAX operating system. Years ago, MS paid a big settlement over this!

tooki

[Maflynn]

You mean to tell me that Microsoft actually stole something, I'm shocked absolutly shocked



Mike

[theolein]

Wow, what fun. All of us expounding on our knowledge on what makes OSX Unix, NT VMS and Mac better than PC.

I think our friend klonji might be more than confused after a while around here

For what it's worth (and a bit of fun) I'll add my salt to the broth.

The Windows NT kernel was developed by, amongst others, members of the VAX team from Digital Research. That was the basis of the suit against Microsoft.

The Windows Registry is a much larger and much more important system database on Windows than the Netinfo database on OSX. Some of their functions are also similar, in that if Netinfo goes down, you won't be able to use much of OSX. User authentification stuff and network information is stored there in OSX, but under Windows just about everything is stored in the Registry. This means that on a modern WindowsXP machine, with a load of software, the Registry can easily become around 50MBytes or more. It stores all programme information, hardware information, security information, network information under Windows. It only got a sense of security under WindowsNT, but is still a favourite place for Virus authors to destroy or store info on their vriuses. It also tends to get corrupted over time and can quite easily get so bad that your Windows system will no longer boot. (Happened to me recently).

This is one of my favourite beefs about Windows. I don't think PC's are worse than Macs and WindowsXP is actually quite stable compared to previous incarnations of Windows. PC's and Microsoft didn't only get where they got due to cheating, stealing and bullying (although that's certainly a part of it), the fact that PC's come from a myriad of manufacturers and are therefore cheap also makes quite a difference.

[Superchicken]

haha anyone find it funny that before Jobs came back Amelio wanted to turn Apple into a high end server company selling windows NT products!? HAHAHA!

that kills me! cause after all I bet Apple would have done AWSOME selling win NT hahahaha

[himself]

I'm no computer-historian or computer science expert, but one of the many flaws i hear a lot about in the various versions of windows (besides the registry) is the "spaghetti-code," which is probably at the root of all of the Windows instabiliy/insecurity. From what I understand, the code is so mangled/tangled and poorly documented, that nobody (probably not even Microsoft) can account for the functions/effects of much of the code. Which can expalin why MS is releasing security updates/service packs so often, and why applying one patch invariably uncovers another hole someplace else in the system. Then again, maybe Mircosoft designed that way intentionally�.

[Gavin]

Here's some gory details about what's going on under the hood to make a UNIX system nifty.


Some quick history.

UNIX was designed to solve several problems with computers in large institutions like universities the military and corporations, places where you had one big computer used by lots of people at the same time. You had problems like you would come to school and find out that some idiot had erased six months worth of your project files, a badly written bit of code could crash the whole computer which meant that no one on campus could do anything until they booted the computer back up (which could take hours !), programs only ran one at a time so you had to wait til the other guy's program was done before you could go, memory was very expensive so you didn't have much ram available.

Macs and PCs had a totally different purpose. Only one person would ever need to use it at a time so their operating systems were designed for that. Also, UNIX needed more oomph than any home computer had. A PC just couldn't run UNIX, but an OS designed for a large institution would be overkill for a PC anyway so why would you want to.

Eventually the small computers became powerful enough to run UNIX and with the need for security, resource hungry apps like photoshop, office workers sharing computers, etc., people actually had a use for it.

So, was has UNIX got?

Multiple users & file security
UNIX can handle lots of users on the same box, each with ownership permissions on their files to keep other people from touching them. And extra file permissions on system files to keep the users from screwing it up.

Multi-tasking
The system can pull programs on and off the CPU in succession so that many programs can run at the same time. Add this to multiple users and I can be checking my email while you are writing a paper at the same time on the same computer.

Protected memory
This keeps the programs from stepping on each other's data. On OS 9 a program could overwrite info the system was using and could hang the computer, this can't happen with UNIX based OSX.

Virtual Memory
The system uses the disk drive as if it were extra ram. It keeps track of data that's not being used and moves it to the disk so a running program can use the ram instead. It brings the data back in when it needs it. That's called 'swapping' and when a lot of it is happening you get the beach ball.

Time & smart guys
UNIX has had decades of some very smart people from all over the world chipping in to make it better, so it tends to be fast, bug free and stable. Classic mac and windows have added their own versions of multitasking and virtual memory over the years but it really couldn't keep up.


There is a lot more about UNIX that makes it flexible and powerful. I find myself constantly impressed with how straight forward and logical it is.

[Richard Edgar]

I don't believe that UNIX was the first OS to do any of the above things. Nor is the account of how UNIX came to be one I have ever seen before (there are several, but they seem to be based around a decision that it was easier to write a new OS for a PDP-11, rather than port one particular game). As for "fast, bug free and stable" .... I would suggest having a read of bugtraq.

[fortepianissimo]

Here

"UNIX Haters Handbook"
http://research.microsoft.com/~daniel/uhh-download.html

Keep in mind it's 10-year old, and the editor now works in M$.

But still an interesting read.

[trusted_content]

Alright, some of this has already been said, but I guess I'll chip in my share.

UNIX is an operating system that was developed at AT&T Bell Labs in the 1970's to run on PDP-11 systems. It comprised a kernel, which is the core of the OS which handles interaction between applications and hardware, and a 'userland', which is the set of tools which make it useful; these include shells (command-line interfaces), system utilities, compilers, editors, etc. UNIX was written in C, as well as all of the original userland, and C is still to this day the primary language for UNIX development.

UNIX quickly became more than AT&T's operating system, though. A team at Berkeley developed something called BSD (Berkeley Standard Distribution), which was a free reimplementation of UNIX. After a series of lawsuits, the BSD codebase was completely cleaned of any AT&T code, thus making it an entirely different tree.

Something called the POSIX certification was developed, which is little more than a detailed operation of what facilities an operating system must make available; this includes specifications for networking, multitasking, signalling, etc. POSIX is the defintion most people follow when it comes to 'what is UNIX' as any system that provides a POSIX environment can easily compile the same applications and provide the same services. This is why applications can be written that are easily portable to OS X, BSD, Linux, Solaris, even Windows NT with only a few minor changes.

GNU/Linux is another independtly-developed OS which follows the POSIX certification and is thus considered by most people to be 'UNIX'. However, it isn't. The interesting part of the OS is that the kernel and userland were developed by different parties; Linux, the kernel, was initially developed by Linus Torvalds, Alan Cox, and thousands of other developers, whereas most of the userland was developed by the GNU project (stands for GNU's not UNIX).

OS X is a BSD derivative with the OpenStep frameworks lying on top (OpenStep = an objective-c API ( application programming interface ) and userland developed by NeXT which is now part of Apple ).

[Gavin]

Originally posted by Richard Edgar:
I don't believe that UNIX was the first OS to do any of the above things. Nor is the account of how UNIX came to be one I have ever seen before

I didn't mean to imply that it was first with these features. And my post was not to be taken as a 'history of unix'. I was simply trying to illustrate with broad strokes the differences in construction and purpose between UNIX OSs and those of traditional desktop PCs. Also that the basic assumptions for what a system should do and how it should behave favor the UNIX way of doing things for modern desktops, which of course is why Apple and Microsoft are both moving in this direction.

As for "tend to be fast, bug free and stable" .... I would suggest having a read of bugtraq.

Sure, but everything has bugs. Are you trying to suggest that OS9 and Win98 are more stable, faster and generally more reliable than OSX, WinXP, or Solaris? I stand by my statement.
Long term real world batle testing good.

[Richard Edgar]

Are you trying to suggest that OS9 and Win98 are more stable, faster and generally more reliable than OSX, WinXP, or Solaris?

Of course not. I believe that UNIX derivatives are probably the best OSs in mainstream use. However, I also believe that that is not a compliment to UNIX, but a comment on the state of OS design.

Long term real world batle testing good.

Some comments on that: If you read the O'Reilly book on UNIX and internet security, it comments that, until the early nineties, the phrase "secure UNIX system" was regarded as an oxymoron. Furthermore, picking through bugtraq, one sees that a rather good proportion of the security holes found (on whatever OS) are buffer overruns - and there is no excuse for that these days. This links to the point that the Internet Worm (strictly, I believe, a UNIX worm - I don't think any non-UNIX systems were affected, apart from DoS) occurred in 1987, which was quite a while after UNIX was first released (early seventies). Hence I also think that complaining about the security of NT (a perfectly valid complaint) while lauding the security of UNIX has a slight whiff of double standards.