[yann63]

The author removed the coloring, because the default setup is for ls to list files with colors. He uses an environment variable to do that.

Wouldn't it be simpler to use \ls instead of ls? This way you get the "basic version of the executable", not some alias. I always use \command instead of command in my shell scripts, because you never know which aliases a user set up.

[Pawamoy]

But aliases are not supposed to be available in subprocesses/scripts, unless you use shopt -s expand_aliases. Even if they were, you cannot ask all your users to rewrite their scripts to use \ls instead of ls.