Overview
- Hailey released WSL9x on Codeberg under GPL-3, enabling Linux 6.19 to run side by side with Windows 95, 98, and ME.
- WSL9x uses three pieces to work: a patched Linux kernel, a Windows 9x VxD driver, and a small DOS client that provides a console window.
- Because both kernels run in ring 0, a crash or exploit in one can take down the other, which the developer warns can create security and stability risks.
- The driver handles system calls by catching general protection faults and treating the int 0x80 instruction as a Linux syscall, a workaround for Windows 9x’s short interrupt table.
- Building it is not plug-and-play, as it needs an i386-musl cross toolchain, Open Watcom v2, a patched kernel branch, and a Windows 9x disk image, though it can run on old 486-era hardware without virtualization as Linux plans to drop i486 support.