How to check the ls version

This topic is about th开发者_如何学Ce util 'ls' The BSD version uses the parameter '-G' to color up the output, while the Linux version uses parameter '--color'

Also the environment variable to set the colors is different: BSD: $LSCOLORS Linux: $LS_COLORS

But now the problem is: I want to determine which version is installed (using a small Shell script), so I can set alias ls and the environment appropriate in my .bachrc file.

As I mentioned above this seems to me to be the handiest method

if ls --color -d . >/dev/null 2>&1; then
    GNU_LS=1
elif ls -G -d . >/dev/null 2>&1; then
    BSD_LS=1
else
    SOLARIS_LS=1
fi

I've essentially this in my l script, which I use on various platforms to tweak ls output as I like

Just run 'ls' and see whether it throws an error, e.g. on my mac:

$ ls --color 1>/dev/null 2>&1
$ echo $?
1

Whereas

$ ls -G 1>/dev/null 2>&1
$ echo $?
0

Indicating -G is supported, but --color is not.

Ironically, the --version switch Kimmo mentions is not supported on most BSD systems :-)

Writing a portable configuration file for your particular setup can be a Herculean task. In your case, if you're sure your .bashrc is going to be used only on GNU/Linux and on a BSD system, you can check for switches that exist in one of the ls' but not in the other: for example, -D doesn't seem to be an accepted switch by ls on my BSD machines (FreeBSD and Mac OS X), whereas it is for GNU ls. Conversely, -P is accepted on BSD, but not on GNU/Linux. Knowing this, you can distinguish between the two ls' and set up environment variables accordingly.

$ ls --version
ls (GNU coreutils) 6.10
Copyright (C) 2008 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Richard Stallman and David MacKenzie.

combining the methods described, here's an easy way to use a bash function instead of an alias in order to make colors work regardless of if you are using BSD or GNU ls.

ll () {
  if ls --version &>/dev/null; then
    ls --color=auto -lahtr
  else
    ls -Glahtr
  fi
}

inspired by a particular conda env recipe pulling in GNU ls on my macOS system where my ls aliases were all hard-coded for stock BSD ls only.