commandlinefu.com is the place to record those command-line gems that you return to again and again.
Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.
If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/
You can sign-in using OpenID credentials, or register a traditional username and password.
First-time OpenID users will be automatically assigned a username which can be changed after signing in.
Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):
Subscribe to the feed for:
greps using only ascii, skipping the overhead of matching UTF chars.
$ export LANG=C; time grep -c Quit /var/log/mysqld.log
$ export LANG=en_US.UTF-8; time grep -c Quit /var/log/mysqld.log
Try strace-ing grep with and without LANG=C
I've used technicalpickles command a lot, but this one handles whitespaces in filenames. I'm sure you want to create an alias for it :)
Just a handy way to get all the unique links from inside all the html files inside a directory. Can be handy on scripts etc.
Handy when you need to create a list of files to be updated when subversion is not available on the remote host. You can take this tar file, and upload and extract it where you need it. Replace M and N with the revisions specific to yours. Make sure you do this from an updated (svn up) working directory.
This one would be much faster, as it's only one executed command.
awk can clear the screen while displaying output. This is a handy way of seeing how many lines a tail -f has hit or see how many files find has found. On solaris, you may have to use 'nawk' and your machine needs 'tput'
Simple but useful little command to unzip all files in a directory.
Save the script as: sort_file
Usage: sort_file < sort_me.csv > out_file.csv
This script was originally posted by Admiral Beotch in LinuxQuestions.org on the Linux-Software forum.
I modified this script to make it more portable.
Kills a process matching program. I suggest using
$ pgrep -fl program
to avoid over-killings
Nice the following: kills all bash process owned by guest
$ pkill -9 -f bash -u guest
- for .xsession use -
Advantages of running a urxvt daemon include faster creation time for terminal windows and a lot of saved memory.
You can start new terminals as childs of urxvtd by typing urxvtc. Another advantage is, that background jobs are always owned by the urxvtd and will survive as long the daemon is running.
This command will output 1 if the given argument is a valid ip address and 0 if it is not.
Files containing ascii art (e.g. with .nfo extension) are typically not correctly reproduced at the command line when using cat. With iconv one can easily write a wrapper to solve this:
if [ -z "$@" ]; then echo "Usage: $(basename $0) file [file] ..."
else iconv -f437 -tutf8 "$@"; fi
Beeps on mouse's every move. Bear in mind that, at least on Ubuntu, /dev/input/mice can be read only by root.
I rarely use the system menu to start applications. I use keyboard shortcuts instead. Keyboard shortcuts are convenient time savers. To configure the shortcuts I use gconf-editor or CompizConfig Settings Manager (if I have Compiz turned on). Lately I've been using Chromium as my browser. Since Chromium is under heavy development it occasionally becomes unusable and I have to switch back to Firefox. I was hard-coding the browser command in my keyboard shortcuts. This became problematic with frequent browser hopping. I now use the xdg-open command when defining my keyboard shortcuts. xdg-open opens a file or URL in the user's preferred application. In the metacity keybinging_commands I have
xdg-open http://gmail.com where I used to have
firefox http://gmail.com. Now when switching browsers I don't have to update each keyboard binding command I just change my default browser in Ubuntu by clicking through the menu: System / Preferences / Preferred Applications / Web Browser.
xdg-open is more convenient for this browser hopper.
Infinitely plays beeps with sinusoidally changing sound frequency. Ideal for alarm on an event.
I spent a bunch of time yesterday looking for the xsel package in Cygwin- turns out you can use the /dev/clipboard device to do the same thing.
If you just want to write or append some text to a file without having to run a text editor, run this command. After running the command, start typing away. To exit, type . on a line by itself.
Replacing the >> with a single > will let you overwrite your file.