This is a rant I have made many times in person: far too many to count. Since I can't possibly warn everybody who might be affected by this, face to face, I'm hoping you will all spread the word.
The problem
To begin with, I should say that
ls --color is useful. It can show you which items in your directory listing are directories, symlinks, broken symlinks, device nodes, named pipes, whatever. I am glad that it exists.
However, let’s consider the basic action of ls. It is, of course, to display which files and directories exist in a directory. This is really quick and easy in Unix. Simply use the libc function
opendir() then just
readdir() till it returns
NULL and
errno is 0. In terms of syscalls, this is an
open(), one or two
read()s and a
close().
When you turn on the
color option, every directory item incurs the weight of an extra
stat() call to see what it is.
Worse still, if it’s a symlink,
ls will obligingly bound across to the thing linked to, to check it exists. If this causes your automounter to wake up and mount something remote, that’s quite an overhead. If your mount hangs because the remote filesystem is unavailable, you can say goodbye to that process; it'll be stuck blocking on a syscall that will never return.
A partial solution
To fix the symlink problem, here’s what you do.
ls was written to avoid chasing symlinks if configured not to. Check your environment variables for the LS_COLORS variable with:
$ env grep ^LS_COLORS
If it exists, you have a config file for colour ls: you should edit
/etc/DIR_COLORS* or copy it to
$HOME/.dircolors and edit it there. Otherwise, type:
$ dircolors --print-database > $HOME/.dircolors
The edit you need to do is to remove or comment out the ORPHAN line from the file.
Unless you were able to edit the file in
/etc, you now need to make sure that this new
$HOME/.dircolors file is used. In your shell login script (
.bash_login for bash and
.login for (t)csh, put the line:
eval dircolors $HOME/.dircolors
(Note that these are backticks, not apostrophes.)
Next time you log in, you'll be able to use colourful ls without fear of a remote filesystem freezing your directory listings.
In conclusion
Use
ls --color when you need it, but as with all powerful tools, use it with care.
Corrections: James pointed out that to dump the default config it is –print-database not –print-directory.
Last week, the Free Software Foundation announced an important new
initiative called End Software Patents whose goals are pretty
evident from the project's name. So far, the initiative is backed by the
FSF, the Public Patent Foundation, and the Software Freedom Law
Center.
There are several organizations who are taking on specific bad patents
but ESP is unique in that it is activitely working toward the
abolition of software patents in the United States. While the
organization is focused on work in the US, it's deeply important
globally -- much of the world's patent law is "exported" from the US.
The FSF is stretching extremely limited resources in backing ESP
to help it get off the ground because we believe two things:
So, sometime over the past few weeks I clocked up ten years as a
Debian developer:
When I'm feeling generous, I imagine this is so that the credit card
companies can give an extra reminder that they only accept certain
credit cards -- not being able to select a card type in an "essential"
input field constrained to multiple choices is a pretty strong reminder.
When I'm feeling less generous, I suspect it might be so that the
companies can subtly remind us that they have their own brand credit
cards that we might like to acquire.
Yesterday witnessed the most important step forward for the 
On Saturday February 9th, at 13:00, I'm going to be joining free
software and anti-DRM activists to 
... is 
(This blog post is in Latvian and is about a public discussion that the capital of Latvia, Riga is having about where to put new bicycle racks in the center of the city. In the post I point to an article describing where to send in suggestions, point out a few possible locations for such racks and suggest installing racks with build-in locks that would require inserting a refundable coin to remove the key locking a bike in place)
R gas dome 
The first phase of the Penny and Martin adventure has come to an
end: after a few days of Wellington, we are now sitting on the
ferry to Picton, beginning our week-long road trip of the South
Island.
Both 