All commands (14,187)

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. 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.

Share Your Commands


Check These Out

Save history without logout
You can use commands that executed on first console from new opened second console. Sometimes it be very useful :)

Open multiple tabs in Firefox from a file containing urls
this will open a new tab in firefox for every line in a file the sleep is removable but i found that if you have a large list of urls 50+, and no sleep, it will try to open all the urls at once and this will cause them all to load a lot slower, also depending on the ram of your system sleep gives you a chance to close the tabs before they overload your ram, removing & >2/dev/null will yield unpredictable results.

Get NFL/MLB Scores/Time
change the nfl in the url to mlb or nba to get those score/times as well

finding cr-lf files aka dos files with ^M characters
its useful to run dos2unix command later on them.

Port Knocking!
Knock on ports to open a port to a service (ssh for example) and knock again to close the port. You have to install knockd. See example config file below. [options] logfile = /var/log/knockd.log [openSSH] sequence = 3000,4000,5000 seq_timeout = 5 command = /sbin/iptables -A INPUT -i eth0 -s %IP% -p tcp --dport 22 -j ACCEPT tcpflags = syn [closeSSH] sequence = 5000,4000,3000 seq_timeout = 5 command = /sbin/iptables -D INPUT -i eth0 -s %IP% -p tcp --dport 22 -j ACCEPT tcpflags = syn

urldecoding with one pure BASH builtin
You can use ordinary printf to convert "%23%21%2fbin%2fbash" into "#!/bin/bash" with no external utilities, by using a little known printf feature -- the "%b" specifier converts shell escapes. Replace % with \x and printf will understand the urlencoded string. BASH's printf has an extension to set a variable directly, too. So you get to convert urlencoded strings from garble to plaintext in one step with no externals and no backticks.

use screen as a terminal emulator to connect to serial consoles
Use GNU/screen as a terminal emulator for anything serial console related. screen /dev/tty eg. screen /dev/ttyS0 9600 MacOSX: http://www.macosxhints.com/article.php?story=20061109133825654 Cheat Sheet: http://www.catonmat.net/blog/screen-terminal-emulator-cheat-sheet/

Grab an interface's IP from ifconfig without screen clutter
Sometimes, you don't really care about all the other information that ifconfig spits at you (however useful it may otherwise be). You just want an IP. This strips out all the crap and gives you exactly what you want.

Safe Russian Roulette (only echo, don't delete files)
Shows "Bang!" in a chance of 1 out of 6, like in the original game with the gun (spin every round). Otherwise, echoes "Click...". If feeling brave you can also do: $[ $[ $RANDOM % 6 ] == 0 ] && echo 'Bang!' && a really killer command || echo 'Click...'

check the status of 'dd' in progress (OS X)
Your platform may not have pv by default. If you are using Homebew on OSX, simply 'brew install pv'.


Stay in the loop…

Follow the Tweets.

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.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

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: