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🪟 Microsoft Open Source MS DOS
On April 25, 2024, Scott Hanselman and Jeff Wilcox made a special announcement on the Microsoft Open Source Blog. Scott Hanselman is a Vice President of Developer Community, and Jeff Wilcox is the Head of Open Source Programms Office.
They write about Ray Ozzie and Mark Zbikowski. The latter one, is in fact the creator of the executable file format. If you’re unsure, you can open any EXE file on your Windows machine.
To do it, I’ve opened the Notepad2.exe with Notepad2 :) :
As you can see the first two characters in the file are MZ. Indeed these are initials of Mark Zbikowski.
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In the blog post the authors share the info that Ray Ozzie found floppy disks with MS-DOS 4.0 and they decided to open source it. If you don’t know what a floppy disk is, it’s like an old-school cloud on a spinning magnetic disk:
Such disks were used to hold data, the most popular one (on the right bottom) held 1.44 MB of goodies. For example Windows was shipped on several of these bad boys. However, the disks with MS-DOS were the older ones.
Everyone was happy with the release of the source code, because it’s an important part of software history. It didn’t go as expected however.
I was able to write the article, because people read it on Medium!
Michal Necasek is running a page called OS/2 Museum, where he covers the history of software. Of course he was more than excited to see the release made by Microsoft. Unfortunately, after the examination it occurs it may not be what it is.
First of all, he found that the files were converted to UTF-8 upon publishing, and more conversions actually caused the source code to break.
But also it seems it’s not the original IBM DOS 4.00 from June 1988, but DOS 4.01:
This further suggests that the source code in fact…
