[pxc]

I use that all the time!

It's also useful if you want to find out where an executable lives when the thing on your PATH is a symlink (sometimes to another symlink, and so on). With GNU coreutils and which, you can run:

  realpath $(which python)
  realpath $(which php)

and so on, in order to start tracking down what package (if any) owns the interpreter on your PATH, or if it belongs to some other management tool, etc. This gives you slightly different information than something like `php --version`.

It's really useful on NixOS, too, since you might have multiple versions of the same package living in your /nix/store, and you want to know which one is the one you're using.