How to check if a program is run in Bash on Ubuntu on Windows and not just plain Ubuntu?

Question

Pretty straightforward, the usual places to figure out the OS you\'re on seem to be identical to plain Ubuntu on Ubuntu for Windows. For example uname -a is ide

Answer 1

For WSL2, we can no longer detect through kernel version because it is running an actual Linux kernel in Hyper-V. However, it still can call explorer.exe existing in every Windows installation. So we could...

if [ -x "$(command -v explorer.exe)" ]; then
echo "We are running on WSL"
fi

This should be a more generic way to detect if the script is running on WSL.

Edit: See answers above. I forgot to count Unix-like environments like Msys2 in.