We just open-sourced DOS 4 (and found binaries of Multitasking DOS 4) https://www.hanselman.com/blog/open-sourcing-dos-4
Open Sourcing DOS 4

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@shanselman
Imagine the possibilities.

An operating system usable by virtually every still-functioning computer in existance today, and a horde of programmers who can work in such a simplified environment that can write virtually any program for any task needed.

Who can write me a DOS 4 web server?

@starraven @shanselman Sounds like a great way to expose 40 years of vulnerabilities to the internet

@saagar @shanselman

Not necessarily. The operating system is old, but all the network software being written for it would be recent.

In any case, it still could potentially give new life to computers doing tasks for which the latest graphics card isn't necessary, and which aren't needed to be connected to the Internet.

@starraven @shanselman Yes but at some point you’d have a kernel component handing packets from the network