Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking us to recommend or find a tool, library or favorite off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it.
Closed 9 years ago.
Improve this question
I'm planning to write an operating system and I don't know very much about operating systems. Are there any good resources or books to read in order for me to learn? What are your recommendations?
We used Andrew Tannenbaum's Modern Operating Systems at the university I attended. I highly recommend it for it's clear explanations of the tradeoffs inherent in many of the design decisions that you'll run up against. This book is a little bit more "fair and balanced" than the Minix book.
I also recommend this book because, despite his net-famous flame war with Linus Torvalds, few of his biases come through in the book. Also, he's a pretty decent writer, and the book is actually entertaining.
Operating Systems Implementation Prentice Software
This book is written by Tanenbaum, the main guy behind Minix, which is what Linux was based on. It provides good overviews for basic OS concepts like memory management, file systems, processes, etc. The concepts in this book book are intimately tied to examples of the Minix OS, which is a good thing.
I think you should start by something like that.
Similar threads on this very site:
OS Development
Building a new operating system
How to get started in operating system development
Operating System Concepts is the book we used at University. It's quite ugly BUT the information inside are well explain (from basic memory management, to how to OS decide what to execute or how to avoid deadlock). Pretty wide.
Os dev website is rich in information if you want to start coding your own OS too,
While old, these books are very good:
Operating System Design with Xinu
http://ecx.images-amazon.com/images/I/51AVJFBS3EL._SL500_BO2,204,203,200_AA219_PIsitb-sticker-dp-arrow,TopRight,-24,-23_SH20_OU01_.jpg
Operating System Design-Internetworking With XINU, Vol. II
3: http://Operating System Design-Internetworking With XINU, Vol. II
Take a look at HelenOS, which is a from scratch microkernel based OS that aims to be a fully modern OS. Disclamer, I'm a contributor, I'm working on its shell from scratch.
HelenOS has been ported to ia32/64, SPARC, ARM and more, its very well designed and easy to read. Its still in its infancy but shows one possible design that really takes advantage of the microkernel design and solves many issues in a microkernel implementation (such as IPC).
It also includes scripts that automatically set up a proper tool chain needed for cross compiling. Its very easy to build and runs very well in most simulators (i.e. QEMU) or bare metal.
I would also study L4, Minix3 and the GNU HURD (based on Mach), the latter being an illustration of design pitfalls when trying to leverage a microkernel.
If you want to go the monolithic route, just study Linux.
I'd highly recommend taking a look at the MIT Operating Systems class. It's got lots of useful references, and a bunch of lab exercises which you can play around with (including automated grading scripts, so you don't have to be an MIT student to do them).
textbook http://ecx.images-amazon.com/images/I/411E3CQQYZL._SS500_.jpg
I used Operating Systems and Middleware: Supporting Controlled Interaction when I was in college. It is probably one of the best textbooks on the subject.
Operating Systems Design and Implementation
The design and implementation of the FreeBSD OS
Just off the top of my head.
Developing Your Own 32-Bit Operating System by Richard A. Burgess. Went into great details about boot loaders, setting up those strange memory and process management registers, etc. It was a great read back in 1996 when i thought i'd take a crack at writing a simple OS from scratch, but may be dated by now, dealing only with the first few generations of Pentium-class CPUs.
If I remember correctly, the Powerup to Bash Prompt HOWTO contained a lot of information that looked like it would be useful for this. So did older versions of the Linux From Scratch HOWTO, but in recent versions that has been removed.
You'll also find a lot of good information in Understanding the Linux Kernel.
I would recommend looking at embedded operating systems and building an embedded OS. It will deal with the core concepts without the overhead of a modern desktop CPU.
I wrote a multitasking embedded OS last spring as a final project, it's easier than you might think.
You should look into MINIX 3. This is an operating system that was written in, I believe, less than 10,000 lines. You can get a very good idea of how an OS works with the aid of one of Tanenbaum's books and understanding how MINIX 3 works. You could go straight to Linux, but I think this is a useful task and really helps you see how it really doesn't take that many lines to build a working OS.
http://www.minix3.org/
Apart from books, there are many sites that learn OS Development
BrokenThorn Entertainment is on of this website that learn OS dev from base
Related
Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking us to recommend or find a tool, library or favorite off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it.
Closed 8 years ago.
Improve this question
Recently I trying to learn Ladder Logic programming for PLCs, but I want to know if there is any IDE to create Ladder programs better that Step7 or cx-programmer? Is there any plugin for Visual Studio or Netbeans that I can use? Finally, is it better to work with PLCs under Linux or Microsoft Windows?
UPDATE 1 : After googling about this, I found out that Ladder programming is not depend on the PLC brand or its model, so I did not mentioned any brand in my question.
What is your goal? In almost all cases, your IDE is dictated by the PLC manufacturer, and your PLC brand is spec'd by the customer when they buy the machine. They spec the PLC because they need to have something that they can go online with for maintenance and troubleshooting. Since the software is proprietary and absurdly expensive, they don't want to get a new software license for every machine in the plant and have to relearn new software, while they are bleeding money of manufacturing downtime.
So if your goal is to enter the industry, you want to find out what plants in country tend to use. In North America it's usually Allen-Bradley a.k.a Rockwell Automation, which is programmed with RSLogix 5000 (edit: the recent versions of RSLogix 5000 have been rebranded as Studio 5000). In Europe, it's typically Seimens, but I have no experience with them.
PLC IDEs are almost always picked hardware first. With some obscure exceptions, you pick the hardware you want to run, and this determines the IDE. The IDEs are all proprietary and unique to each hardware platform. Rockwell Automation alone has three different IDEs to support their hardware lines, all licensed individually and very expensive.
If Omron is the most common in your area, it's a good idea to start with them. Once you get used to one type of PLC, learning more is really easy.
If you don't mind which PLC platform you're using, I really enjoyed my time with RSLogix. They have a free, training-level suite available here:
http://www.ab.com/linked/programmablecontrol/plc/micrologix/downloads.html
I prefer RSLogix 5000. It's one of the easiest to work with and has User Defined Types and Add On Instructions to help with reusability.
ABB has Control Builder (which is the product that I work on), AFAIK when somebody buys our AC800 controller they get the CB for free, at least the so called "Compact version" which is file based. The CB has ladder diagrams as well as all other 1131 languages plus some extensions like Function Diagrams.
Disclaimer Sorry if it sounded like an ad, just very passionate with what I work on.
I am primarily a high level language programmer, but have also done development on various PLC /PAC platforms, including Rockwell, Siemens, and Beckhoff.
If your goal is to merely get an introduction to ladder, nearly anything will due. You can download Beckhoffs TwinCAT software for free. It is only a 30-day license, but you can just continually reinstall every 30 days without issue. The great part of TwinCAT is that it runs on a Windows PC, so you can develop and test code directly on the PC and don't need actual Beckhoff hardware to play with. The ladder is a bit quirky, but the statement list portion is by far one of the more powerful. If you are a C-programmer you will feel very comfortable with Beckhoff, because they have duplicated a lot of C-like functions (e.g. memcpy and setcpy) into their libraries.
The Beckhoff platform is not all that widespread, but it would allow you to learn the principals of ladder and PLC/PAC programming.
I'm looking for any website(s) devoted and/or related to Operating System Development, and would love for you to kindly share any links you may have.
I have searched myself, but keep winding up at the same old sites, and am wondering if there are others that just don't get noticed by the major search engines or something.
I've put this as a community wiki, simply because I don't think it's very fair to judge an answer based on a single link.
Thank you.
I might suggest a book, rather than any website. There are a number of good ones:
Operating Systems: Design and Implementation (Tanenbaum)
Modern Operating Systems (Tanenbaum)
Operating System Concepts (Silberschatz & Galvin)
Unix Systems for Modern Architectures (Schimmel)
Once you understand the concepts, you can start to design and develop for your particular project.
How about a wiki? There's the OSDev Wiki.
I would recommend a couple of books:
Developing Your Own 32-Bit Operating System
Dissecting DOS: A Code-Level Look at the DOS Operating System
Reading these will give you an idea of how an operating system is built and the amount of work it takes to build one.
Here's one website with a tutorial walkthrough: http://www.brokenthorn.com/
(Googling 'operating system development tutorial' reveals several but most seem to be dead ends or links to Linux.)
As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance.
Closed 10 years ago.
I am toying with the idea of creating an completely new operating system and would like to hear what everyone on this forums take is on that? First is it too late are the big boys so entrenched in our lives that we will never be able to switch (wow - what a terrible thought...). But if this is not the case, what should a operating system do for you? What features are the most important? Should all the components be separate installations (in other words - should the base OS really have no user functionality and that gets added on by creating "plug-ins" kind of like a good flexible tool?)
Why do I want to do this... I am more curious about whether there is a demand and I am wondering, since the OSes we use most today (Linux, Windows, Mac OS X (Free BSD)) were actually written more than 20 years ago (and I am being generous - I mean dual and quad cores did not exist back then, buses were much slower, hardware was much more expensive, etc,...), I was just curious with the new technology if we would do anything differently?
I am anxious to read your comments.
To answer the first question: It's never too late. Especially when it comes to niche market segments and stuff like that.
Second though, before you start down the path of creating a new OS, you should understand the kind of undertaking it is: it'd be a massive project.
Is it just a normal programmer "scratch the itch" kind of project? If so, then by all means go ahead -- you might learn alot of things by doing it. But if you're doing it for the resulting product, then you shouldn't start down that path until you've looked at all the current OSes under development (there are alot more than you'd think at first) and figured out what you'd like to change in them.
Quite possibly the effort would be better spent improving/changing an existing open source system. Even for your own experimentation, it may be easier to get the results you want if you start out with something already in development.
First, a little story. In 1992, during the very first Win32 ( what would become the MS Professional Developers Conference ) conference, I had the opportunity to sit with over some lunch with one Mr. Dave Cutler ( Chief Architect of what most folks would now know as Windows NT,Windows 2000, XP, etc. ).
I was at the time working on the Multimedia group at IBM Boca Raton on what some of you might remember, OS/2. Having worked on OS/2 for several years, and recognizing "the writing on the wall" of where OSes were going, I asked him, "Dave, is Windows NT going to take us into the next century or are there other ideas on your mind ?". His answer to me was as follows:
"M...., Windows NT is the last operating system anyone will ever develop from scratch !". Then he looked over at me, took a sip of his beer, and said, "Then again, you could wake up next Saturday after a particularly good night out with your girl, and have a whole new approach for an operating system, that'll put this to shame."
Putting that conversation into context, and given the fact I'm back in college pursuing my Master's degree ( specializing in Operating Systems design ), I'd say there's TONS of room for new operating systems. The thing is to put things into perspective. What are your target goals for this operating system ? What problem space is it attempting to service ?
Putting this all into perspective will give you an indication of whether you're really setting your sights on an achievable goal.
That all being said, I second an earlier commenters note about looking into things like "Singularity" ( the focus of a talk I gave this past spring in one of my classes .... ), or if you really want to "sink your teeth into" an OS in its infancy....look at "ReactOS".
Then again, WebOSes, like gOS, and the like, are probably where we're headed over the next decade or so. Or then again, someone particularly bright could wake up after a particularly fruitful evening with their lady or guy friend, and have the "next big idea" in operating systems.
Why build the OS directly on a physical machine? You'll just be mucking around in assembly language ;). Sure, that's fun, but why not tackle an OS for a VM?
Say an OS that runs on the Java/.NET/Parrot (you name it) VM, that can easily be passed around over the net and can run a bunch of software.
What would it include?
Some way to store data (traditional FS won't cut it)
A model for processes / threads (or just hijack the stuff provided by the VM?)
Tools for interacting with these processes etc.
So, build a simple Platform that can be executed on a widely used virtual machine. Put in some cool functionality for a specific niche (cloud computing?). Go!
For more information on the micro- versus monolithic kernel, look up Linus' 'discussion' with Andrew Tanenbaum.
I would highly suggest looking at an early version on linux(0.01) to at least get your feet wet. You're going to mucking about with assembly and very obscure low-level stuff to even get started (especially getting into protected mode, multi-tasking, etc). And yes, it's probably true that the "big boys" already have the market cornered. I'm not telling you NOT to do it, but maybe doing some work on the linux kernel would be a better stepping stone.
Check out Cosmos and Singularity, these represent what I want from a futuristic operating system ;-)
Edit :
SharpOS is another managed OS effort. Suggested by yshuditelu
An OS should have no user functionality at all. User functionality should be added by separate projects, which does not at all mean that the projects should not work together!
If you are interested in user functionality maybe you should look into participating in existing Desktop Environment projects such as GNOME, KDE or something.
If you are interested in kernel-level functionality, either try hacking on a BSD derivate or on Linux, or try creating your own system -- but don't think too much about the user functionality then. Getting the core of an operating system right is hard and will take a long time -- wanting to reinvent everything does not make much sense and will get you nowhere.
You might want to join an existing OS implementation project first, or at least look at what other people have implemented.
For example AROS has been some 10 or more years in the making as a hobby OS, and is now quite usable in many ways.
Or how about something more niche? Check out Symbios, which is a fully multitasking desktop (in the style of Windows) operating system - for 4MHz Z80 CPUs (Amstrad CPC, MSX). Maybe you would want to write something like this, which is far less of a bite than a full next-generation operating system.
Bottom line...focus on your goals and even more importantly the goals of others...help to meet those needs. Never start with just technology.
I'd recommend against creating your own Operating System. (My own geeky interruption...Look into Cloud Computing and Amazon EC2)
I totally agree that it would first help by defining what your goals are. I am a big fan of User Experiences and thinking of not only your own goals but the goals of your audience/users/others. Once you have those goals, then move to the next step of how to meet it.
Now days what is an Operation System any way? kernal, Operating System, Virtual Server Instance, Linux, Windows Server, Windows Home, Ubuntu, AIX, zSeries OS/390, et al. I guess this is a good definition of OS... Wikipedia
I like Sun's slogan "the Network is the computer" also...but their company has really fallen in the past decade.
On that note of the Network is the computer... again, I highly recommend, checking out Amazon EC2 and more generally cloud computing.
I think that building a new OS from scratch to resemble the current OSes on the market is a waste of time. Instead, you should think about what Operating System will be like 10-20 years from now. My intuition is that they will be so different as to render them mostly unrecognizable by today's standards. Think of frameworks such as Facebook (gasp!) for models of how future OSes will operate.
I think you're right about our current operating systems being old. Someone said that all operating systems suck. And yes, don't we have problems with them? Call it BSOD, Sad Mac or a Kernel Panic. Our filesystems fail, there are security and reliability problems.
Microsoft pursued interesting approach with its Singularity kernel. It isolates processes in software, using a virtual machine similar to .NET, and formal verification methods. Basically all IPC seems to be formally specified and verified, even before a program is ran.
But there's another problem with it - Singularity is only a kernel. You can't run application not designed for it on it. This is a huge penalty, making eventual transition (Singularity is not public) quite hard. If you manage to produce something of similar technical advantages, but with a real transition plan (think about IPv4->IPv6 problems, or how Windows got so much market share on desktop), that could be huge!
But starting small is not a bad choice either. Linux started just like this, and there are many cases when it leads to better design. Small is beautiful. Easier to change. Easier to grow. Anyway, good luck!
checkout singularity project,
do something revolutionary
I've always wanted an operating system that was basically nothing but a fresh slate. It would have built in plugin support which allow you to build the user interface, applications, whatever you want.
This system would work much like a Lua sandbox to a game would work, minus the limitations. You could build a plugin or module system that would have access to a variety of subsystems that you would use. For example, if you were to write a web browser application, you would need to load the networking library and use that within your plugin script. Need 'security' ? Load the library.
The difference between this and Linux is that, Linux is an operating system but has a windows manager that runs over top of it. In this theoretical operating system, you would be able to implement the generic "look" and "feel" of a variety of windows within the plugin system, or could you create a custom interface.
The difference between this and Windows is that its fully customizable, and by fully I mean if you wanted to not implement any cryptography at all, you can do that, or if you wanted to customize an already existing window, you can do that. Nothing is closed to you.
In this theoretical operating system, there is an OS with a plugin system. The plugin system uses a simple and powerful language.
If you're asking what I'd like to see in an operating system, I can give you a list. I am just getting into programming so I'm not sure if any of this is possible, but I can give you my ideas.
I'd like to see a developed operating system (besides the main ones) in which it ISN'T a pain to get the wireless card to work. That is my #1 pet peeve with most of the ones I've tried out.
It would be cool to see an operating system designed by a programmer for other programmers. Have it so you can run programs for all different operating systems. I don't know if that's possible without having a copy of windows and OSX but it would be really damn cool if I could check the compatablity of programs I write with all operating systems.
You could also consider going with MINIX which is a good starting point.
To the originator of this forum, my hats off to you sir for daring to think in much bolder and idealistic terms regarding the IT industry. First and foremost, Your questions are precisely the kind you would think should engage a much broader audience given the flourishing Computer Sciences all over the globe & the openness taught to us by the Revolutionary Linux OS, which has only begun to win the hearts and minds of so many out there by way of strengthing its user-friendly interface. So kudos on pushing the envelope.
If I'm following correctly, you are supposing that given the fruits of our labor thus far, the development of further hardware & Software concoctions could or at least should be less conventional. The implication, of course, is that any new development would reach its goal faster than what is typical. The prospect, however, of an entirely new OS system #this time would be challenging - to say the least - only because there is so much friction out there already between Linux & Windows. It is really a battle between open source & the proprietary ideologies. Bart Roozendaal in a comment above proves my point nicely. Forget the idea of innovation and whatever possibilities may come from a much more contemporary based Operating System, for such things are secondary. What he is asking essentially is, are you going to be on the side of profit or no? He gives his position away easily here. As you know, Windows is notorious for its monopolistic approach regarding new markets, software, and other technology. It has maintained a deathgrip on its hegemony since its existence and sadly the windows os is racked with endless bugs & backdoors.
Again, I applaud you for your taking a road less travelled and hopefully forgeing ahead and not becoming discouraged. Personally, I'd like to see another OS out there...one much more contemporary.
Closed. This question needs to be more focused. It is not currently accepting answers.
Want to improve this question? Update the question so it focuses on one problem only by editing this post.
Closed 7 years ago.
Improve this question
I am planning to develop an operating system for the x86 architecture.
What options of programming languages do I have?
What types of compilers are there available, preferably on a Windows environment?
Are there any good sources that will help me learn more about operating system development?
Is it better to test my operating system on a Virtual Machine or on physical hardware?
Any suggestions?
For my final year project in collage I developed a small x86 OS with a virtual memory manager, a virtual file system and fully preemptive multitasking. I made it open source and the code is heavily commented, check out its source forge page at:
https://github.com/stephenfewer/NoNameOS
From my experience I can recommend the following:
You will need x86 assembly language for various parts, this in unavoidable, but can be kept to a minimum. Fairly quickly you will get running C code, which is a proven choice for OS development. Once you have some sort of memory manager available you can go into C++ if you like (you need some kind of memory manager for things like new and delete).
No matter what language you choose you will still need assembly & C to bring a system from boot where the BIOS leaves you into any useable form.
Ultimately, the primary language you choose will depend on the type of OS you want to develop.
My development environment was the Windows port of the GNU development tools DJGPP along with the NASM assembler. For my IDE I used IBM's Eclipse with the CDT plugin which provides a C/C++ development environment within Eclipse.
For testing I recommend BOCHS, an open source x86 PC emulator. It lets you boot up your OS quickly which is great for testing and can be integrated into eclipse so you can build and run your OS at the push of a button. I would also recommend using both VMWare and a physical PC occasionally as you can pick up on some subtle bugs that way.
P.S. OS development is really fun but is very intensive, mine took the best part of 12 months. My advice is to plan well and your design is key! enjoy :)
Language and compiler depend entirely on what you're attempting to accomplish. I would suggest, though, that you might be approaching the problem from too low a level.
There are materials out there on operating system fundamentals. MIT has OpenCourseware on the subject. Read through Andrew Tannenbaum's Operating Systems series, and look at things like Minix.
Get an idea for what's out there. Start tinkering with things. Borrow ideas, and see where they go. You can reinvent the wheel if you really want, but you'll learn more by building on the works of others.
It doesn't really matter, what language you choose. If the language is Turing-complete, then you can write an OS in it.
However, the expressiveness of the language will make certain kinds of designs very easy or very hard to implement. For example, the "liveliness" and dynamism of the old Smalltalk OSs depends on the fact that they are implemented in Smalltalk. You could do that in C, too, but it would probably be so hard that you wouldn't even think about it. JavaScript or Ruby OTOH would probably be a great fit.
Microsoft Research's Singularity is another example. It simply couldn't be implemented in anything other than Sing#, Spec# and C# (or similar languages), because so much of the architecture is dependent on the static type safety and static verifiability of those languages.
One thing to keep in mind: the design space for OSs implemented in C is pretty much fully explored. There's literally thousands of them. In other languages, however, you might actually discover something that nobody has discovered before! There's only about a dozen or so OSs written in Java, about half a dozen in C#, something on the order of two OSs in Haskell, only one in Python and none in Ruby or JavaScript.
Try writing an OS in Erlang or Io, and see how that influences your thinking about Operating Systems!
There is an OS course offered at the University of Maryland that utilizes GeekOS. This is a small, extensively commented OS designed for educational purposes which can be run using the Bochs or QEMU emulators.
For an example of how it is used in a course, check out a previous offering of the course at the class webpage. There, you will find assignments where you have to add different functionality to GeekOS.
Its a great way to get familiar with a small and simple OS that runs on the x86 architecture.
You might want to look up XINU. it's a tiny OS for x86 that isn't really used for anything other than to be dissected by students.
Use ANSI C, and start off with an emulator.
When you port over to a real machine, there will be some assembler code. Context switching and interrupt handling (for instance) is easier to write in assembler.
Andy Tannenbaum has written a good book on OS. Many other good ones exist.
Good luck! There is nothing quite like haveing written your own OS, however small.
Also check out the OSDev.org which have all information you need to get started.
I've done that once for a 386SX, which was on a PCI board. A good source on how to start a X86 cpu in protected mode is the source code of linux. It's just a few assembly statements. After that you can use gcc to compile your C code. The result is objectcode in ELF format. I wrote my own linker, to make a program out of the objectcode. And yes, it worked! Good luck.
Be sure to check out the answers to my question:
How to get started in operating system development
Without a doubt, I'd use Ada. It's the best general-purpose systems-programming language I have come across, bar none. One example, Ada's much better for specifying bit layout of objects in a record than C. Ada also supports overlaying records on specific memory locations. C requires you to play with pointers to acheive the same effect. That works, but is more error-prone. Ada also has language support for interrupts.
Another: Safety. Ada defaults to bound checking array assignments, but allows you to turn it off when you need it. C "defaults" to no bound checking on arrays,so you have to do it yourself manually whenever you want it. Time has shown that this is not the right default. You will forget one where it is needed. Buffer overflow exploits are the single most common security flaw used by crackers. They have whole websites explainng how to find and use them.
As for learning about doing this, the two books I'm aware of are XINU (Unix backwards, nothing to do with Scientology), and Project Oberon. The first was used in my Operating Systems graduate course, and the second was written by Nikalus Wirth, creator of Pascal.
If you are making a full OS, you will need to use a range of languages. I would expect Assembly, C and C++ at the very least.
I would use a Virtual Machine for most of the testing.
C most probably...all major OS-es have been written in C/C++ or Objective-C(Apple)
If you want write an OS then you need a couple of people. A OS can not write a single people. I think it is better to work on existing OS projects
Reactos --> C, Assembler
SharpOS --> C#
JNode --> Java
This is only a short list of OS projects. How you can see there is a project for every possible language.
Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking us to recommend or find a tool, library or favorite off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it.
Closed 8 years ago.
Improve this question
One thing I've always wanted to do is develop my very own operating system (not necessarily fancy like Linux or Windows, but better than a simple boot loader which I've already done).
I'm having a hard time finding resources/guides that take you past writing a simple "Hello World" OS.
I know lots of people will probably recommend I look at Linux or BSD; but the code base for systems like that is (presumably) so big that I wouldn't know where to start.
Any suggestions?
Update: To make it easier for people who land on this post through Google here are some OS development resources:
Writing Your Own Operating System (Thanks Adam)
Linux From Scratch (Thanks John)
SharpOS (C# Operating System) (Thanks lomaxx)
Minix3 and Minix2 (Thanks Mike)
OS Dev Wiki and Forums (Thanks Steve)
BonaFide (Thanks Steve)
Bran (Thanks Steve)
Roll your own toy UNIX-clone OS (Thanks Steve)
Broken Thorn OS Development Series
Other resources:
I found a nice resource named MikeOS, "MikeOS is a learning tool to demonstrate how simple OSes work. It uses 16-bit real mode for BIOS access, so that it doesn't need complex drivers"
Updated 11/14/08
I found some resources at Freebyte's Guide to...Free and non-free Operating Systems that links to kits such as OSKit and ExOS library. These seem super useful in getting started in OS development.
Updated 2/23/09
Ric Tokyo recommended nanoos in this question. Nanoos is an OS written in C++.
Updated 3/9/09
Dinah provided some useful Stack Overflow discussion of aspiring OS developers: Roadblocks in creating a custom operating system discusses what pitfalls you might encounter while developing an OS
and OS Development is a more general discussion.
Updated 7/9/09
LB provided a link to the Pintos Project, an education OS designed for students learning OS development.
Updated 7/27/09 (Still going strong!)
I stumbled upon an online OS course from Berkley featuring 23 lectures.
TomOS is a fork of MikeOS that includes a little memory manager and mouse support. As MikeOS, it is designed to be an educational project. It is written in NASM assembler.
Updated 8/4/09
I found the slides and other materials to go along with the online Berkeley lectures listed above.
Updated 8/23/09
All questions tagged osdev on stackoverflow
OS/161 is an academic OS written in c that runs on a simulated hardware. This OS is similar in Nachos. Thanks Novelocrat!
tangurena recommends http://en.wikipedia.org/wiki/MicroC/OS-II, an OS designed for embedded systems. There is a companion book as well.
Linux Kernel Development by Robert Love is suggested by Anders. It is a "widely acclaimed insider's look at the Linux kernel."
Updated 9/18/2009
Thanks Tim S. Van Haren for telling us about Cosmos, an OS written entirely in c#.
tgiphil tells us about Managed Operating System Alliance (MOSA) Framework, "a set of tools, specifications and source code to foster development of managed operating systems based on the Common Intermediate Language."
Update 9/24/2009
Steve found a couple resources for development on windows using Visual Studio, check out BrokenThorn's guide setup with VS 2005 or OSDev's VS Section.
Updated 9/5/2012
kerneltrap.org is no longer available. The linux kernel v0.01 is available from kernel.org
Updated 12/21/2012
A basic OS development tutorial designed to be a semester's project. It guides you through to build an OS with basic components. Very good start for beginners. Related paper. Thanks Srujan!
Updated 11/15/2013
Writing a Simple Operating System From Scratch. Thanks James Moore!
Updated 12/8/2013
How to make a computer operating system Thanks ddtoni!
Updated 3/18/2014
ToAruOS an OS built mostly from scratch, including GUI
Updated Sept 12 2016
Writing your own Toy Operating System
Updated Dec 10 2016
Writing a Simple Operating System —from Scratch (thank you #Tyler C)
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.
An excellent resource is the material of the MIT course 6.828: Operating System Engineering.
XV6 - simple Unix-like teaching OS written in ANSI C for x86
http://pdos.csail.mit.edu/6.828/2012/xv6.html
XV6 source - as a printed booklet with line numbers
http://pdos.csail.mit.edu/6.828/2012/xv6/xv6-rev7.pdf
XV6 book - explains the main ideas of os design
http://pdos.csail.mit.edu/6.828/2012/xv6/book-rev7.pdf
The material is compact: 92 pages source and 96 pages commentary.
I like it more than the Minix book! It's a true gem!
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.
I found Robert Love's Linux Kernel Development quite interesting. It tells you about how the different subsystems in the Linux kernel works in a very down-to-earth way. Since the source is available Linux is a prime candidate for something to hack on.
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
My operating systems course in undergrad had us building a number of subsystems for OS/161, a simple, BSD-like kernel that provides some of the basics while leaving the freedom to explore various design space decisions in implementing higher-level services.
Start hacking away at Minix. It's a lot smaller than Linux (obviously) and it's designed with teaching purposes in mind (some, at least). Not Minix 3 though, that's a whole different story.
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
I would like to include this repo How-to-Make-a-Computer-Operating-System by Samy Pesse. Is a work-in-progress. Very interesting.
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.
A simple and basic OS development tutorial designed to be a semester's project. It guides you through to build an OS with basic components. Very good start for beginners. Related paper is here.
One reasonably simple OS to study would be µC/OS. The book has a floppy with the source on it.
http://en.wikipedia.org/wiki/MicroC/OS-II
Check out the Managed Operating System Alliance (MOSA) Project at www.mosa-project.org. They are designing an AOT/JIT compiler and fully managed operating system in C#. Some of the developers are from the inactive SharpOS project.
I've toyed with Cosmos, which is "an operating system project implemented completely in CIL compliant languages." It's written in C#, so that was right up my alley. For someone like myself who has never attempted to build an operating system, it was actually pretty cool to be able to get a "Hello World" operating system running in no time.
Check out this site: http://osix.net/modules/article/?id=359
As mentioned above, the OSDev Wiki is (by far) the best source for OS development. For those of you who speak German, the lowlevel.eu Wiki is also great. Something relatively unknown Incitatus OS, a simple kernel with a tiny set of userspace apps. It's great to use for getting into the complicated topic of OS development.
Movitz is a Lisp environment written in Common Lisp and running "on the metal". Unfortunately, some links on the Movitz main page deny access, but you can find instructions on how to download and compile the source code from the trac page. Also, a ready image can be found on the archive of this page.
IMHO this is utmost interesting, as it brings back the Lisp machine concept on the currently available hardware. It failed commercially, but this does not prove to me that the idea was bad.
The Unix haters handbook is a fun book that semi-seriously berates the concept of Unix and its derivatives. Many sections argument about how better the Lisp machine concept was.
Here's a paper called "Writing a Simple Operating System From Scratch". It covers writing a bootloader, entering x86-32 protected mode, and writing a basic kernel in C. It seems to do a good job at explaining everything in detail.
The x86 JS simulator and ARM simulator can also be very useful to understand how different pieces hardware works and make tests without exiting your favourite browser.
Intresting Question for the programmers. See it will take long long long time to build OS like Windows or Mac but if you want build a simple ones then you can try your best
You need to focus on Assembly Language,C and C++. You should be expert in these languages.
First read a good book on how OS works[Google it], then read all the info from Wiki OS
Search in youtube "How to create your own OS in Assembly Language" watch the video, Eg. Video
Download Linux OS source code and compile it yourself and try to modify the code yourself
Now you are an experienced OS editor now download Minix and QNX and start developing with them and get their docs from here Minix Doc and QNX Doc
Now you have gained the master degree(Not completely just a little more to go) in creating OS now distribute this knownledge to your freinds and with their help try to create an OS as powerful as Mac, Linux or Windows
When you have made a basic operating system it's actually hard to continue because there isn't many ressources on making GUIs or porting libraries. But i think taking a look at ToAruOS would help a lot!
The code under the surface of that OS is so damn simple! but at the same time he has ported things like cairo, python, (not yet but soon) sdl, made share memory and he has also made his own widget toolkit. It's all written in C.
Another interesting OS would be pedigreeOS. It's made by JamesM (the man behind jamesM's kernel tutorial. While it has more features than ToaruOS it's also bigger and more confusing.
But anyway these 2 OS will help you a lot especially ToAruOS.
When I started working on my basic operating systems I needed a basic guide like Stepping stones for a basic operating system. It helped me not loose my head.
That if you want to make it from absolutely nothing (pure assembly code)