Considering that Windows NT has the concept of so-called ‘subsystems’ whereby you can run different systems side-by-side, starting with the POSIX subsystem and later the Windows Subsystem for Linux (WSL), it was probably only a matter of time before someone figured that doing this with Windows 9x was also completely reasonable. Ergo we now got [Hailey Somerville]’s Linux Subsystem for Windows.
To make running Linux inside Windows 9x work, it was necessary to heavily patch a Linux kernel, as normally there are no provisions for such a subsystems in Windows 9x’s kernel unlike the NT kernel. Correspondingly, the Linux kernel is based on user-mode Linux and hacked to call Windows 9x kernel APIs instead of the POSIX ones.
In order to use WSL9x you thus need to build said modified Linux kernel – currently at version 6.19 – along with a disk image containing an installed copy of Windows 9x. From there WSL9x can be loaded with the wsl command and you’re then free to cooperatively run the Win9x and Linux kernel side-by-side. This is reminiscent of Cooperative Linux (coLinux), which did something similar except with Windows NT and Linux kernels running side-by-side, and of course we have WSL2 with Windows 10+.
Thanks to [adistuder] for the tip.








