[radarsat1]

I like the idea of the Linux Test Project. Neat.

I'm curious, does the WSL actually use any parts of Linux under the hood, or is it just an emulation of the user space, like Cygwin?

[abrowne]

It uses a Linux-compatible kernel interface with no Linux kernel code plus Ubuntu's userland. I guess that's why they sometimes call it Bash on Windows. I'm surprised no one's proposed "Windows Subsystem for GNU".

[azinman2]

Because the main bit is translating Linux syscalls to windows. Which isn't gnu.

[cryptarch]

Isn't the main use of WSL "first-class GNU tools for Windows"?

I can't really imagine people running anything other than development tools on WSL, and most of those come from the GNU project.

[bitwize]

Nope.

It traps the software interrupt which initiates a system call under Linux and the Windows kernel takes over, emulating that system call.