What are some resources for getting started in operating system development?

There are a lot of links after this brief overview of what is involved in writing an OS for the X86 platform.

The link that appears to be most promising (www.nondot.org/sabre/os/articles) is no longer available, so you'll need to poke through the Archive.org version to read it.

At the end of the day the bootloader takes the machine code of the kernel, puts it in memory, and jumps to it. You can put any machine code in the kernel that you want, but most C programs expect an OS so you'll need to tell your compiler that it won't have all that, or the bootloader has to create some of it.

The kernel then does all the heavy lifting, and I suspect it's the example kernel you want. But there's a long way to go between having a kernel that says, "Hello world" to having a kernel that loads a command interpretor, provides disk services, and loads and manages programs.

You might want to consider subscribing to ACM to get access to their older literature - there are lots of articles in the late 80's and early 90's in early computing magazines about how to create alternative OSs. There are likely books that are out of print from this era as well. You might be able to get the same information for free by looking up the indexes of those magazines (which are available on that site - click "index" near the magazine name) and then asking around for people with a copy.

Lastly, I know that usenet is dead (for so sayeth the prophets of internet doom) but you'll find that many of the craggy old experts from that era still live there. You should search google groups (they have dejanews's old repository) and I expect you'll find many people asking the same questions a decade or 1.5 ago that you're asking now. You may even run across Linus Torvalds' many queries for help as he was developing linux originally. If searches don't bring anything up, ask in the appropriate newsgroup (probably starts with comp.arch, but search for ones with OS in the name).

Minix is a lot smaller, and designed for learning purposes, and the book to go with it is a good one too.

Update: I guess Minix 3 is a bit of a different goal, but Minix 2 (and of course the first version) were for teaching purposes.

As someone who has written a real-time multi-tasking operating system from scratch...

keyboard debounce routine, keyboard driver, disk driver, video driver, file system, and finally a boot-loader - and that's just to launch it for the first time with nothing to do!

... I cannot emphasize enough how important it is to get familiar with the hardware! This is especially so if you really want to do it all yourself instead of just picking up a primitive system someone else has already laid out for you. For example, contact Intel and ask them for a CPU card for your type of CPU! This will lay it out for you - the "pin-outs", interrupts, opcodes, you name it!

Remember the hardware makes it all possible. Study the hardware. You won't regret it.

.

Write a microcontroller OS. I recommend an x86 based microcontroller. A modern OS is just huge. Learn the basics first.

I wish there was one place to get all of the info about developing your own OS. The closest to come to that is OS Dev Wiki and Forums. They offer a ton of good information regarding the setup, development, and device hardware information.

Also there are some great tutorials at BoneFide, I've used the getting started tutorial by Bran, and am now looking at a more recent one based on his called Roll your own toy UNIX-clone OS.

I second checking out: "Operating Systems : Design and Implementation"

And if you want to develop on Windows, check out jolson's blog post.

Edit: For development on windows using Visual Studio, check out BrokenThorn's guide or OSDev's wiki.

you also might want to take a look at SharpOS which is an operating system that they're writing in c#.

There are good resources for operating system fundamentals in books. Since there isn't much call to create new OS's from scratch you won't find a ton of hobbyist type information on the internet.

I recommend the standard text book, "Modern Operating Systems" by Tanenbaum. You may also be able to find "Operating System Elements" by Calingaert useful - it's a thin overview of a book which give a rough sketch of what an OS is from a designer's standpoint.

If you have any interest in real time systems (and you should at least understand the differences and reasons for real time OS's) then I'd also recommend "MicroC/OS-II" by Labrosse.

Edit:

Can you specify what you mean by "more technical"? These books give pseudo code implementation details, but are you looking for an example OS, or code snippets for a particular machine/language?

-Adam

Just coming from another question. I'd like to mention Pintos... I remembered my OS course with Nachos and Pintos seems to be the same kind of thing that can run on x86.

Here are some other Stack Overflow pages worth incorporating into this discussion:

Roadblocks in creating a custom operating system
Developing an operating system for the x86 architecture

Already answer, but when I took Operating Systems in college we started with an early linux kernel and added simplistic modern features (basic file systems, virtual memory, multitasking, mutexes). Good fun. You get to skip some of the REALLY crazy low level assembly only stuff for mucking w/ protected mode and page tables while still learned some of the guts.

http://kerneltrap.org/node/14002 http://kerneltrap.org/files/linux-0.01.tar.bz2

You might want to look at linuxfromscratch.

Linux From Scratch (LFS) is a project that provides you with step-by-step instructions for building your own custom Linux system, entirely from source code.