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The platform sells well to people who want a Unix, not people who want to hack the OS.

What about people who want to hack up an OS using a Mac? (raises hand) Believe it or not, cross compiling to the x86 platform using a PPC Mac and QEMU actually works. It's actually a better development environment than Windows, because you don't have to work around Windows' lack of Unix tools.

If you're weird like me, check out the OS FAQ for information on creating your own operating system, including the building of a cross-compiler. Bonefide also has some great tutorials on getting going with your operating system construction project.

"So when did C++ start running on bare hardware? Every time I've run it, I needed an OS and a huge pile of libraries."

Well then mister.. you obviously haven't tried hard enough, it is perfectly possible to write kernel-level code in C++ as long as you implement the 'new' and 'delete' functions which are required to create and delete objects.

A reference if you need it: http://www.mega-tokyo.com/osfaq2/index.php/Doing%2 0a%20kernel%20in%20C%2B%2B

Oh my god.. dont tell me.. you have to write your own memory manager?... dumbasss, if you're writing bare-level C code you'll have already done that.

In future.. think before you type, and you'll be relieved of the pain of being publicly insulted on slashdot..

Note that, on x86, VC++ and most other PC compilers use a stack-based unwinding and handling mechanism known as SEH, common to OS/2, Windows and Windows NT and described in detail in a famous MSJ article, http://www.microsoft.com/msj/0197/Exception/Except ion.aspx. GCC and most other UNIX compilers, instead, use the same table-based mechanism that is the rule on RISC architectures on x86 too. Also note that any use of stack-based SEH may or may not be covered by USPTO patent #5,628,016, held by Borland International, Inc. SEH on RISC architectures is table-based, thus unaffected by the patent)

Indeed, good starting place is Mega Tokyo forums and specifically the Book recommendations and Quick links threads, which together contain the answer to the question..

Indeed, good starting place is Mega Tokyo forums and specifically the Book recommendations and Quick links threads, which together contain the answer to the question..

Indeed, good starting place is Mega Tokyo forums and specifically the Book recommendations and Quick links threads, which together contain the answer to the question..

I did this years ago. Had a quick boot floppy with a dumb OS that did almost nothing. But it was still cool "just for fun."

As I suggested, google is your friend.

Google gives you this first: http://mega-tokyo.com/osfaq2/.

And this might be good for FS (Fat12) http://www.free2code.net/tutorials/other/20/os1.ph p

I wondered about the future of fan-AGI, so I asked Ken Williams... Ken's Reply

If you can find a copy, "Bebop Bytes Back" (found here) is a wonderful book. Despite the childish title, the book will walk you through designing a computer, from scratch. An included CD-ROM provides you with all sorts of routers, simulators, and so forth, including a few IMSAI simulators.

Even if you don't actually build a computer, you'll feel like you've done when you make it through this book. Bebop To The Boolean Boogie and Designus Maximus Unleashed are also very good tutorials.

These books aren't going to teach you how to build with off-the-shelf components. They're going to help you understand bus-level logic and so forth.

From there, you may want to look into the How to Write Your Own Operating System page, which will help you get something running on the ahrdware you put together.

It's not how big your OS kernel is, it's what you do with it that matters ;-)

Hurd [is] now obsolete too.

This is really bad news, since it hasn't even hit a 1.0 release yet :-)
Why do you say this? not being arguementative - just interested.

I just want to highlight this link from the previous post. I hadn't seen this site before, and I really wish I had found it a year ago when I started getting into OS coding.
If you are at all interested in OS coding, check it out.

cheers,
G

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...

I'd definitely recommend checking out the OS FAQ:

Here

You can! Its called Sarien, and I'm the primary author. Its comming along slowly (myself and claudio who do most of th work are very busy), but we are getting there. (we just had announcements for Mac and Acorn ports!!)..

If you want to play old AGI games on nix boxen from sun ultra's to linux xfree etc, Check out Sarien.

www.mega-tokyo.com/sarien

Write your Own Operating System [FAQ]!