Darwin forked BSD, and BSD is a fork of the original Unix source. Linux is a fresh implementation of POSIX, and doesn't directly inherit any code from Unix. Li

Darwin forked BSD, and BSD is a fork of the original Unix source. Linux is a fresh implementation of POSIX, and doesn't directly inherit any code from Unix. Linux is as much Unix as WSL1 was Linux - i.e. not at all, just clones.