UNIX: Strange output if piped to less

Question

If I execute ls command with pipe to less, I get strange output

ESC[00mESC[00mfile1.ccESC[00m
ESC[00file2.ccESC[00m
ESC[00file3.ccESC[00m

(means ESC string in between).

Without ls, the output is:

file1.cc    file2.cc    file3.cc

How to correct this?

Answer 1

I'm guessing that you have the --color=always option to ls set, either through and alias, funtions or the LS_COLORS environment variable and ls is sending color directives to a non-terminal (i.e. your pipe to less).

Answer 2

What you're seeing are ANSI escape sequences for setting colors. Run ls --color=no.

Answer 3

Use less -R or set the LESS environment variable to -R.

Answer 4

You need to make less output raw control characters using less -r.