According to people who are way more interested in this than I am, there was a bunch of licensed software in 5 and 6.
Comment on Microsoft releases MS-DOS 4 source code on GitHub — 45 year old code now open-source
mozz@mbin.grits.dev 6 months ago
But not 5.0 yet - they still got critical proprietary stuff in EDIT and SMARTDRV.SYS that they don’t want their competitors to get a hold of.
xyzzy@lemm.ee 6 months ago
IonicFrog@lemmy.sdf.org 6 months ago
I wonder if they licensed the source of 5.0+ to someone and are still getting paid for it. If so, it’s probably something ubiquitous and critical that nobody would think of like traffic lights or water treatment plants.
CatTrickery@lemmy.blahaj.zone 6 months ago
I think that is likely since 3.3 wasn’t included either and that is one of those versions people stuck with for ages.