which is a Go implementation of the UNIX command of the same name.

Its main (and only) advantage over the standard command is its -l flag that makes it resolve symbolic links. This can be especially useful when using Homebrew.

The executable works exactly like the which command:

which [-as] program ...

In addition, it supports a -l command which makes which resolve symbolic links before printing the paths.

However, note that this implementation doesn’t support combined flags (e.g. -al won’t work, you’ll have to use -a -l).

You’ll have to ensure that $GOPATH/bin is at the beginning of your PATH environnment variable if you want to use this implementation instead of the original one.

go install github.com/bfontaine/which@1.0.1

$ which vim
/usr/local/bin/vim

$ which -l vim
/usr/local/Cellar/vim/7.4.712_1/bin/vim

$ which -a vim
/usr/local/bin/vim
/usr/bin/vim

which is also usable as a Go library:

package main

import "github.com/bfontaine/which/which"

// get the first executable in $PATH
executable := which.One("vim")

// get all executables in $PATH
executables := which.All("vim")

I know it doesn’t really make sense to re-write a simple tool like which, but I needed the -l option so I wrote this. I use Homebrew on macOS and it installs binaries in a directory then symlinks them into /usr/local/bin/, which means it’s not possible to get the original path by using the original which command alone.