A Minor Update: The Source Code for MS-DOS 4.01 Is Here
Microsoft released the source code for MS-DOS 4.00 a few weeks ago. Thanks to meticulous reverse engineering, we now also have the sources for 4.01.
GitHub - lotharsm/MS-DOS at dos-4.01-reconstructed
github.comThe original sources of MS-DOS 1.25, 2.0, and 4.0 for reference purposes - lotharsm/MS-DOS