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Configuring LS_COLORSApril 11th, 2008
The directory lister under UNIX is called ‘ls’. In the deep and distant past this was a very black and white affair. GNU has changed all that by introducing an environment variable called LS_COLORS which allows you to set the colours of files based on extension, permissions and file type.
As usual the instructions on how to configure it are locked away so that only a privileged few know how to configure them. When I started looking for this holy grail, I came across some poor guy who had worked it out through trial and error. I thought that there must be some documentation, somewhere on the internet. But, no! I have pieced together all the information I could find from mail list postings, support forums and when I eventually found it, the source code.
I will attempt to describe what I have discovered on my journey so that others may start from here with a better understanding of how LS_COLORS works.
The BSD implementation of
ls used in BSD, FreeBSD and MacOS is slightly different. It uses a set or unset CLICOLOR environment variable or the
ls command line switch -G to indicate whether to use the colours defined in the environment variable LSCOLORS. Whereas GNU’s
ls uses the command line switch −−colour and the environment variable LS_COLORS instead (Thanks Gilles).
If you do not specify a colour to use then the default will be used, which is why unsetting LS_COLORS has no visible effect. The defaults can be obtained by running the dircolors command.
The database in question is a globally readable file which can be overridden depending on your terminal type. The database file is initially set to
/etc/DIR_COLORS then overridden with one of the following. The first being the least precedent and the last being the most.
This configuration file has several options:
- COLOR - either tty (add colour to ls when output is on the command line), all (all colours to ls on the command line and when piping i.e.
ls > file.txtwill have colour coding information in it) and none (switch off).
- OPTIONS - strictly not related to LS_COLORS. This allows you to add extra options to the ls command.
- TERM - one line per terminal type that supports colour.
- EIGHTBIT - 1 (on) or 0 (off) to allow 8-bit output.
- and finally the colour definitions for file type and file extensions.
On most systems the ls command has been aliased to use the coloured option by default:
alias "ls=ls --color=auto"
The LS_COLORS environment variable is a colon separated list of key=colour pairs. There are 2 types of key: file types and file extensions.
Below is a list of all the keys (that I know of!). Thanks to Bartman for his starter page.
|no||NORMAL, NORM||Global default, although everything should be something|
|ln||SYMLINK, LINK, LNK||Symbolic link. If you set this to ‘target’ instead of a numerical value, the color is as for the file pointed to.|
|pi||FIFO, PIPE||Named pipe|
|bd||BLOCK, BLK||Block device|
|cd||CHAR, CHR||Character device|
|or||ORPHAN||Symbolic link pointing to a non-existent file|
|su||SETUID||File that is setuid (u+s)|
|sg||SETGID||File that is setgid (g+s)|
|tw||STICKY_OTHER_WRITABLE||Directory that is sticky and other-writable (+t,o+w)|
|ow||OTHER_WRITABLE||Directory that is other-writable (o+w) and not sticky|
|st||STICKY||Directory with the sticky bit set (+t) and not other-writable|
|ex||EXEC||Executable file (i.e. has ‘x’ set in permissions)|
|mi||MISSING||Non-existent file pointed to by a symbolic link (visible when you type ls -l)|
|lc||LEFTCODE, LEFT||Opening terminal code|
|rc||RIGHTCODE, RIGHT||Closing terminal code|
|ec||ENDCODE, END||Non-filename text|
|*.extension||Every file using this extension e.g. *.jpg|
The keys (above) are assigned a colour pattern which is a semi-colon separated list of colour codes.
|100||Dark grey background|
|101||Light red background|
|102||Light green background|
|104||Light blue background|
|105||Light purple background|
Most of the defaults are all right and not really worth changing. By default, executable directories show up as white on a light green background and normal directories which are blue on a black background. Both of these settings make your eyes go funny! So here is how to change just them.
The above snippet changes both directories colours to grey.
Just as an aside, the easiest way to remap your colours is via the client control interface. I use PuTTY which allows you to redefine the terminal colour settings, but I think I’ll save that for another block entry!
1) the fact that anyone makes a comment is nice!
2) It's another link to LS_COLORS which is a bit of a complicated affair, so the more links the better.
I know that I get about 400 page views (per month) of this article, but if I mention affair, will I get all the porn hunters looking here? Oh no, I've mentioned porn does that mean I'll get even more? I'll analyse the blog stats over the next couple of months and let you know... (in another blog!)
thanks for any help.
It's an interesting request, you may want to email the GNU team and add it as a feature request or bug.
Try here: GNU FileUtils Project
97 - White (-:
Sure enough, I tried them out and they all work! Awesome. (now I'm gonna waste a good chunk of time seeing how I can further customize all my syntax highlighting, LS_COLORS, zsh completion menu colors, etc etc...)
Where did you find out about these?
it's very useful way to change color.
overwrites a possible existing configuration of LS_COLORS, you can juste substitute the existing definition with sed (stream editor) as follows :
LS_COLORS="`echo $LS_COLORS |sed 's/di=[0-9]*;[0-9]*/di=01;34/; s/ow=[0-9]*;[0-9]*/ow=01;34/'`"
Otherwise, a very useful tutorial.
1. dircolors --print-database > ~/.dircolors
2. vi .dircolors
3. update bashrc to look for ~/.dircolors (as per info page referenced in "man dircolors")
if [ -x /usr/bin/dircolors ]; then
test -r $d && eval "$(dircolors $d)" || eval "`dircolors -b`"
Thanks for all the info.
A couple of things - you are missing at least two key - mh/MULTIHARDLINK for "Regular file[s] with more than one link" and ca/CAPABILITY for "File with capability."
Also, and I haven't seen this anywhere, if you're feeling bold you can use the 256 colors of xterm instead of ANSI colors. You want to set the value of the key to the whole xterm escape sequence, as in \033[38;5;159. 38 there refers to foreground, 48 would be background. 159 is the color. Colors can be separated w/ the letter 'm', and ANSI escapes for underline, bold, flash, etc. can also be tacked on with an 'm,' as in \033[38;5;159m\e[04 (same as above, only underlined.)
I dread that the above will get eaten in the commenting process… :)
bd BLOCK, BLK Black device
In my opinion, blue-on-black and green-on-white are both ugly. : -)
unalias ls ;
alias | egrep ls
alias l.='ls -d .* --color=tty'
alias ll='ls -l --color=tty'
alias ls='ls --color=tty'
It is ok to create new aliases that are not spelled the same as the standard commands. But I feel very strongly that you should never change the behaviour of an existing command such as ls. The last thing you want is to have your script changing behaviour (breaking) based on the configuration of the user running it.
This is a great guide. Thanks for writing it.