all 2 comments

[–]useless_aether 6 insightful - 2 fun6 insightful - 1 fun7 insightful - 2 fun -  (0 children)

..read the source code

[–]fred_red_beans 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (0 children)

There's the old acronym RTFM...

user@machine~$ man ls

or

user@machine~$ ls --help

I'm generally pretty impressed with how well documented things are in linux.