OS adventures

[TandyMan100]

Have any of you ever programmed your own Operating System? If so, could you please state:

Name of OS
Date created
system
download link (if neccessary)

Also, what is your favorite of the 'big' OSes?

 

[barythrin]

A friend and I started writing one in 2002 or so. We never got it fully completed to release it so it stayed as Acorp PoC OS (proof of concept). If we kept it obsolete it would have been easier but we had it reading fat12, fat16, and I think we were working on fat32 but what killed the proof of concept project was memory management (protected mode). It was difficult for us to wrap our heads around the memory address matrix and at that point became much more work than fun which killed the mood of the project. We got it working but it was such a PITA and we had to look at other code to figure it out which kinda sucked in my mind.

The next part was going to be other OS compatibility and internal debugging (another one of those "how the heck do we.." concepts which we had some of it working after a while) but we had it reading files off the floppy, and basically if it was written with bios interrupts it could run stuff by typing the name of the file. So we were going to start emulating some of the MSDOS interrupts, then start emulating other OSes. The point was actually to port our OS to other obsolete systems (6502, Z80, etc) but after a while became difficult and too long to really be portable.

I wrote most of my stuff in debug which had it's moments, then testing on a virtual machine was interesting but we ended up with a few bugs in the VM software and had to use a spare system or two to test it each time.

 

[docred]

I wrote some bootstrap code (x86) at one point - thats as far as I got, never got back to the project I had been playing around with learning to use a PC as an embedded controller type unit and such. Now you've made me start thinking about it again...

 

[cosam]

I've been programming a couple of operating systems (if you can even call them that) for a Z80 system I built. I say "programming" (present tense) because as with most of my projects, it's a bit of an on-and-off affair. I started about five years ago and neither are anywhere near complete! Every now and again I'll dig out the sources and start hacking again. Even if they don't amount to much, it's a great learning experience and I quite enjoy low-level coding, as opposed to writing "boring" apps and such.

As for links, you can find the more elaborate of the two, which also runs on the Sinclair Spectrum here. The other is more what you'd call a monitor for the Z80 project I mentioned (the sources are linked to from there).

 

[pontus]

Indeed we wrote a fairly functional thingy for a course in operating systems concepts.

It had a interrupt handler, multitasking, a simple terminal which could start new processes and monitor them, message passing between processes and it also sported a ridiculous memory management scheme which I've luckily forgotten.. I think we wrote part of the c-library ourselves as well. It was named TermOS and was for some MIPS machine.

 

[chuckcmagee]

No on Operating System. I did write a device driver and the interface for a 9 track tape drive. The company I worked for used my code to do all their client file backups. It used double buffering and would stream the data to the tape as fast as the tape would go.

Nobody knows COBOL anymore but I also got the boss to pay me to modify the COBOL compiler. COBOL has this statement where you can use one comannd to move tons of items. It is called "MOVE CORRESPONDING" and it matches up the item names to be moved. Comes in very handy for writing report programs where you have to move items from the disk record to the print line. I obtained the source code for the compiler from IBM on mag tape and it took me 6 months of long hard hours to get the additional functions into the compiler. IT WAS THE MOST FUN I HAVE HAD MY ENTIRE LIFE. Nothing is more fun than being paid for what you love to do. It would be 10 o'clock at night and I would be pouring over a hexidecimal memory dump, looking for problems.

Of course, the boss never did recoup my time with improved coding times. The computer industry moves so fast that the computer (IBM 1130) was very close to totally obsolete about the time I finished the compiler mods. Which is why I was able to get the source code in the first place. As we know, IBM is not known for handing out their source to viable products.

 

[barythrin]

lol great memories to read about. I was waiting and so excited to start writing drivers too but never got into it. Wrote a lot of fun code though and even the painful stuff was fun when we were over it but writing whenever we could physically hang out and then not getting it to work by the end of our free time each weekend.

Plus multiple people writing code has always been a headache for us, goals eventually change and though cool, I wanted to focus more on a base OS to run on vintage gear and write hardware diagnostics for different systems, and my friend wanted a cleaner OS to compile C and other languages on.

 

[Chuck(G)]

You need more choices for the OS poll.

I've participated in several commercial OS projects and wrote great chunks of code for them, but would in no wise state that "I wrote it all myself." Consider that an operating system includes all of the things that make the machine usable, not just an I/O handler and command processor. There are editors, compilers, system management utilities, diagnostics, communication and networking programs--all manner of things. And then the stuff has to be documented and tested if others are to use it. Programmers make miserable testers in my experience.

That's a lot to ask of one person.

 

[Ole Juul]

Yes, that was a rather limited list for computer lovers! Here's a better one
http://www.dmoz.org/Computers/Software/Operating_Systems/x86/

Those are x86 - go up one directory for much more. OK, I agree lots of those aren't all viable for everyday use, but you gotta atleast include the popular DOSes like DR and FreeDOS. Also QNX is pretty common and Minix3 is usable already. I'm sure some people here use other OSes regularly afterall, this is a computer forum. There are certainly some more older and quite viable ones and it seems to me I've heard CP/M mentioned here a couple of times. VBG

I use an MS-DOS kernel for my everyday writing, but all the DOSes seem to be mixable so you couldn't really call my system "MS-DOS" as such.

My second choice is Linux which I use for browsing and media, but for text, it's got a long way to go before it catches up with DOS.

My third choice hasn't been written yet.

 

[barythrin]

Right, I had a coworker at my last job that had a Pentium 100Mhz machine which he always kept BeOS on. It was entertaining that he'd never let it go or let anyone touch it since the helpdesk manager wanted to scrap it. Honestly, I'm not sure what else he used it for besides an mp3 player but he certainly loved it and it was a neat little OS.