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Microsoft open-sources MS-DOS 4.00, releases early beta of MS-DOS 4.0 (multitasking)
Today, in partnership with IBM and in the spirit of open innovation, we're releasing the source code to MS-DOS 4.00 under the MIT license. There's a somewhat complex and fascinating history behind the 4.0 versions of DOS, as Microsoft partnered with IBM for portions of
www.osnews.comMicrosoft open-sources MS-DOS 4.00, releases early beta of MS-DOS 4.0 (multitasking) – OSnews
@osnews DOS v4.0 was a bugger with managing memory. DOS 5 was sublime, with the ability to load device drivers (and some of DOS itself) into high memory, out the way of the precious 640k base memory.