MSDOS 6.22 not opensourced yet :(

[igor_kavinski]

But MSDOS 4.0 has been opensourced:

Microsoft Open-Sources MS-DOS 4.0 Under MIT License - Phoronix

www.phoronix.com

10 more years to wait for 6.22?

 

[VirtualLarry]

dr dos? freedos?

 

[manly]

Umm wow, this is an interesting story. I didn't know there was an MT-DOS aka European MS-DOS 4.0. It supported preemptive multitasking. 🤯

It's a separate branch from MS-DOS 4.x, which is what Microsoft found in their archives and open sourced.

The Multitasking DOS beta disks are also published, courtesy of former CTO Ray Ozzie.

MS-DOS/v4.0-ozzie at main · microsoft/MS-DOS

The original sources of MS-DOS 1.25, 2.0, and 4.0 for reference purposes - microsoft/MS-DOS

github.com

 

[igor_kavinski]

dr dos? freedos?

Never used those. I used and I guess enjoyed MSDOS 6.2 in that era on a 486 DX2-66.

 

[manly]

Of course an OS/2 guy isn't happy with Microsoft. 😛

How Not To Release Historic Source Code | OS/2 Museum

www.os2museum.com

 

[Steltek]

But MSDOS 4.0 has been opensourced:

Microsoft Open-Sources MS-DOS 4.0 Under MIT License - Phoronix

www.phoronix.com

10 more years to wait for 6.22?

I think that even as recent as 2-3 years ago, MS-DOS 6 was still being used for embedded systems. As a result, you probably won't be seeing the sources for it for awhile.

The released sources are buildable and runnable, anyway.

 

[ssokolow]

Never used those. I used and I guess enjoyed MSDOS 6.2 in that era on a 486 DX2-66.

DR-DOS is neat. It's essentially an advanced descendant of CP/M (yes, Gary Kildall and his employees showing they could leapfrog Microsoft) pretending to be MS-DOS and, later on in MS-DOS's lifespan, Microsoft actually wanted to license its superior technology but couldn't reach an agreement. (Among other things, it came with built-in competitors to famous Quarterdeck products like QEMM and DESQview.)

It later got bought by Novell, so the version contemporary to MS-DOS 6.22 was marketed as Novell DOS 7.

Another funny thing is that Novell/DR-DOS 7 was what became of the memory manager code that Apple was considering using for their secret early 90s collaboration named the Star Trek project (because "To boldly go where no Mac has gone before"). If it hadn't been cancelled, Apple would have ported Mac OS to Intel x86 in the 90s instead of PowerPC.

Here are the backs of a couple of retail boxes I picked up for my collection with the intent to play around with them on a suitably old x86-based thin client I also recently picked up. (When looking at the features being promoted, keep this timeline in mind. DR-DOS 5.0 beat MS-DOS 5.0 to market by 14 months. DR-DOS 6.0 came out only three months after MS-DOS 5.0, and 18 months before MS-DOS 6.0. Novell DOS 7 came out three months after MS-DOS 6.0.)