Reading the articles around the source release of GWBASIC I now recall that Microsoft released the source to DOS 1.25 and 2.0 under an MIT license a while back so I can get an open source DOS on my Compaq portable on a version closer to what it came with(I think it may have been 2.0) rather than FreeDOS which may have been a resource hog and even require a memory expansion. Neat.
@bsharitt I've often wondered about availability of these old operating systems.
It'd be nice to tinker with CP/M and FlexOS again.
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