devolopin a mew lang........ 1752

On Sunday 02 July 2006 15:18, prashant stood up and spoke the following words to the mbuttes incomp.os.linux.misc...:

Well, answering that isn't as easy as you may think it is... Several of the other posters have given you links to webpages and-or books on the subject of writing operating systems, so I'm not going to dub those links here again.

However, I will emphasize that it's important to get to know the instructionset of the microprocessor platform you intend to write this new OS for. For instance, one cannot compare an Intelx86instructionset with the micro-ops of an UltraSparc, MIPS or PPC.

It's imperative that you understand the CPU you are going to program for. CPU's have an instructionset, and - as is the case on thex86platform - often a set of macros, which combine multiple instructions from this instructionset into one.

Well, microprocessors operate in a binary fashion. There are several "programming languages" available, ranging from the first generation programming in either binary or hexadecimal code to the actual first programming language for CPU's, beingbuttembler.

MS-DOS, the very first original version of Unix written by Ritchie and Thompson for the in-house PDP-7 at AT&T Bell Labs - i.e. before Unix was rewritten in C - and the earlier MacIntosh operating systems were all written in buttembler code. The advantage of buttembler code is that you can really implement shortcuts and fast, tailored code at the very low level, but the downside of it is that you'd need to write a *lot* of code, since you really have to specify everything.

That's why people developed higher programming languages such as Fortran, C, COBOL, BASIC, Pascal, etc. These languages require less instructions and can work with "larger building blocks" than buttembler code, because each "such building block" - being a procedure or function - is a kind of macro to loads of smaller instructions.

In the end however, everything has to be translated into binary code again, because that's the only thing a CPU understands. So the bottom line is: yes, you need a compiler of some sort, or at the very least an buttembler.

Well, there are plenty of simple operating systems, ranging from embedded operating systems over to CP-M or MS-DOS. There is a Free version of DOS available - i.e. FreeDOS - which you can download here...

However, this is a Free Software implementation of DOS. If you're really interested in operating system design, you would be able to learn more from studying the Linux kernel, which is freely available for download from...

... - click on the "F" next to the kernel generation you're interested in to download the full sources tarball, and then unpack this tarball using...

... from the commandline of any UNIX operating system. I'm afraid I can't give you any instructions on how to unpack it in Windows as my knowledge of Windows is mainly theoretical.

The Linux kernel is written in C, with some snippets of buttembler here and there - this is often done to make low level code faster - and is organized as a directory structure, in which you will find code for all supported hardware platforms and for all the available drivers - including sound, video, human input devices, et al - and comes with loads of documentation.

As for the choice of compilers,gccused to stand for "the GNU C compiler", but nowadays it's been re-interpreted as being "the GNU Compiler Collection", asgccsupports more than just C or C++.

Lastly, the obvious... If you want to write an operating system or an operating system kernel, you'll need something to write it *on,* i.e. a working computer. You can't just take a bare computer and start entering code into it.

Computers require an operating system to be present - even if it's only on a floppy - when they boot up, so you have to find a way to code your kernel together and to have it be loaded into the computer's memory and executed by the CPU at boot time.

Or in short: it takes a working operating system to be able to write another operating system. ;-)

I hope you won't take this to your offense, but that's not the idea of Usenet. I notice you are posting from Google Groups, and so possibly you are under the impression that Usenet is a forum that exists on Google Groups - something Google itself is partly responsible for.

However, Usenet is just another part of the Internet, and is actually even older than the Internet itself. It's a network comprised of newsservers that are all (more or less) kept in sync with eachother.

Best would be for you to use a real newsreader instead of the web-based (and broken) Google Groups interface. In GNU-Linux, you can make use ofKNode,-Pan,-tin,-slrnand a whole bunch of other newsreaders. In Windows, you can useOutlook-ExpressorThunderbird. The latter also exists for GNU-Linux and Mac OS-X.

You can subscribe to a free newsserver if your ISP doesn't offer you one, e.g. via this free news service:

You will find the details on their website.

It is not good courtesy to ask for personal e-mail advice on Usenet. The idea behind Usenet is the sharing of information, and also: multiple people know more than one, so multiple people can participate in the conversation and give you their opinion or advice.

Sharing information and knowledge are the keystones behind Free & Open Source Software. ;-)

Hope this was helpful... ;-)

-- With kind regards,

*Aragorn* (Registered GNU-Linux user #223157)