Microsoft open-sourced MS-DOS 4.0.

[wx69wx2023]

Today Microsoft open-sourced MS-DOS 4.0.

You can check it out here: https://github.com/microsoft/MS-DOS

MS-DOS v1.25, v2.0, v4.0 Source Code
This repo contains the original source-code and compiled binaries for MS-DOS v1.25 and MS-DOS v2.0, plus the source-code for MS-DOS v4.00 jointly developed by IBM and Microsoft.

The MS-DOS v1.25 and v2.0 files were originally shared at the Computer History Museum on March 25th, 2014 and are being (re)published in this repo to make them easier to find, reference-to in external writing and works, and to allow exploration and experimentation for those interested in early PC Operating Systems.

[NON]

@wx69wx2023 This looks interesting, but I am unable to compile it. I agree that I am a little weak at programming, lol
They don't teach much in college these days!
Any hints? I used FASM.

[blue_devil]

Gentleman this is old news. M$ already shared MS-DOS' sources like 10 years ago:
Apparently the now make the archive.

You can read the article here:

https://computerhistory.org/blog/microsoft-ms-dos-early-source-code/

[wx69wx2023]

Originally Posted by Gregory Morse

@wx69wx2023 This looks interesting, but I am unable to compile it. I agree that I am a little weak at programming, lol
They don't teach much in college these days!
Any hints? I used FASM.

I only have mobie now, I should try to build when I am at home.
.
See the Runme.bat, it give the guide.
echo off
cls
echo **********************************************************************
echo * *
echo * MS-DOS 4.00 Build Notes *
echo * *
echo * The following steps must be taken to ensure a proper and *
echo * complete build of the MS-DOS 4.00 sources. *
echo * *
echo * 1.) Build environment setup, the setenv.bat batch file provided *
echo * will automate this process. This batch file must be modified *
echo * to reflect the individual build environment, ie the drive *
echo * volume and path. *
echo * *
echo * 2.) The nmake utility is used to build the MS-DOS 4.00 sources. *
echo * the global build is started by invoking nmake at the top- *
echo * most directory level. Individual modules are built by *
echo * changing to the particular directory and running nmake. *
echo * Useful Nmake switches: *
echo * *
echo * NMAKE -I : Ignore build errors. *
echo * NMAKE -I -X - Redirect to FILENAME : Redirects stdout-stderr *
echo * *
echo * 3.) After the build is complete the cpy.bat batch file can be *
echo * used to gather the binaries. The cpy.bat file will copy the *
echo * binaries to the directory specified on the command line. *
echo * For example: *
echo * *
echo * To use cpy.bat to copy the binaries to the bin directory on *
echo * C: drive you would use the following command: *
echo * *
echo * cpy c:\bin *
echo * *
echo * *
echo **********************************************************************
echo on


So you must run Setenv.bat first,and have installed nmake.

[wx69wx2023]

Originally Posted by blue_devil

Gentleman this is old news. M$ already shared MS-DOS' sources like 10 years ago:
Apparently the now make the archive.

You can read the article here:

https://computerhistory.org/blog/microsoft-ms-dos-early-source-code/

My dude, it is not old, the news link:
https://cloudblogs.microsoft.com/opensource/2024/04/25/open-sourcing-ms-dos-4-0/


Today MS open-sourced Dos 4.0, you can check the project v4.0 create-time on github.

Not ver 1.25/2.0

[chants]

This is a duplicate thread created 2 hours after

https://forum.exetools.com/showthread.php?p=130726#post130726

[NON]

Originally Posted by wx69wx2023

I only have mobie now, I should try to build when I am at home.
.
See the Runme.bat, it give the guide.
echo off
cls
echo **********************************************************************
echo * *
echo * MS-DOS 4.00 Build Notes *
echo * *
echo * The following steps must be taken to ensure a proper and *
echo * complete build of the MS-DOS 4.00 sources. *
echo * *
echo * 1.) Build environment setup, the setenv.bat batch file provided *
echo * will automate this process. This batch file must be modified *
echo * to reflect the individual build environment, ie the drive *
echo * volume and path. *
echo * *
echo * 2.) The nmake utility is used to build the MS-DOS 4.00 sources. *
echo * the global build is started by invoking nmake at the top- *
echo * most directory level. Individual modules are built by *
echo * changing to the particular directory and running nmake. *
echo * Useful Nmake switches: *
echo * *
echo * NMAKE -I : Ignore build errors. *
echo * NMAKE -I -X - Redirect to FILENAME : Redirects stdout-stderr *
echo * *
echo * 3.) After the build is complete the cpy.bat batch file can be *
echo * used to gather the binaries. The cpy.bat file will copy the *
echo * binaries to the directory specified on the command line. *
echo * For example: *
echo * *
echo * To use cpy.bat to copy the binaries to the bin directory on *
echo * C: drive you would use the following command: *
echo * *
echo * cpy c:\bin *
echo * *
echo * *
echo **********************************************************************
echo on


So you must run Setenv.bat first,and have installed nmake.

Thank you! I'd previously missed out so many intermediate steps. Now with the help of the info you've provided, it's compiling correctly.

[wx69wx2023]

Originally Posted by chants

This is a duplicate thread created 2 hours after

You are right, I didn’t check before posting.

[wx69wx2023]

Originally Posted by Gregory Morse

Thank you! I'd previously missed out so many intermediate steps. Now with the help of the info you've provided, it's compiling correctly.

You are welcome, my dude.

[WhoCares]

Why doesn't MS open source the other versions of MS-DOS?

[NON]

Originally Posted by WhoCares

Why doesn't MS open source the other versions of MS-DOS?

The "good" ones were the MS-DOS v3.30 and 5.0a. Even the version 6 was not so bad.
The v4.0 is the "bad" one. Much the Windows Vista, which was not well received by the community.
It's no wonder they did not want to release the source code of the "good" versions.

Unless officially released by Microsoft as open source, leaked sources cannot be used for any legit purposes.
Even the site with the leaked sources have mentioned this prominently:

I am already aware of the leaks. They are useless for me.
I need to be able to use the sources in software that I can sell!

It's true that I sell cracked software from my home. I am a hard-core pirate and I do not deny that.
But for software that I create to sell as developed software, I cannot use the code unless it is official open sourced.

[chants]

3.3 is already on the web, though likely someone here hasn't learned to search so lmgtfy:

https://linuxreviews.org/42.9_GB_Of_Microsoft_Source_Code_Leaked:_Historicans_Can_Now_Study_The_Source_Code_For_MS-Dos_3.3_To_Windows_XP

V7.1 is the good one but AFAIK the Windows 95 source never leaked with this version? XP and 2000 are too late

[Eleven]

Originally Posted by chants

3.3 is already on the web...

I remember reading through the old leaked source code years ago and checking the MS-DOS 4.0 code release I'm glad they left all the swearing in the comments and names:

invoke	path_search			; find the mother (result in execpath)
or	AX, AX				; did we find anything?
je	badcomj45			; null means no (sob)
cmp	AX, 04H 			; 04H and 08H are .exe and .com
jl	rsrch_br1			; fuckin' sixteen-bit machine ought
jmp	execute 			; to be able to handle a SIXTEEN-BIT
rsrch_br1:				; DISPLACEMENT!!

[Fyyre]

So very memory lane. DOS 3.3 was the first version I used => I also agree with the fellow above, DOS 4.0 was meh. 6.22 was my favorite.

Still waiting for that Windows 7 (even Vista!...) source code leak. That will be, a beautiful thing.

[Eleven]

I think most if not all I did on DOS was 6.22 and I have nothing but good memories of tweaking autoexec.bat and config.sys to get specific games to run, and poking around in qbasic before I knew any other languages even existed.

Funny how different it was back then, games were just coming out and not working without effort if you weren't on the latest system or whatever the most common was at the least, and a lot of people were cool with that. I was a kid and wasn't paying the bills so maybe that helped