POSIX was implemented as a subsystem.
And it was never _fully_ implemented, as my post said. The NT kernel doesn't support certain POSIX semantics (fork).
WSL1 DOES implement fork() for WSL1 lightweight processes in the lxcore.sys driver: https://learn.microsoft.com/en-gb/archive/blogs/wsl/windows-...
Isn’t Win32 also implemented as a subsystem?
WSL1 DOES implement fork() for WSL1 lightweight processes in the lxcore.sys driver: https://learn.microsoft.com/en-gb/archive/blogs/wsl/windows-...