Color output is not on by default in 'ls'. Your 'ls' must be an alias for the real ls with some options. For example, mine is: $ type ls ls is aliased

Color output is not on by default in 'ls'. Your 'ls' must be an alias for the real ls with some options. For example, mine is: $ type ls ls is aliased to `ls --color=auto' A quick way to run the original 'ls' (not the aliased version), just prefix it with backslash: $ \ls ... Or: $ command ls ...