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

Verify/edit bash history command before executing it
Bash history commands are those that begin with the character ! (eg. the most popular 'sudo !!' Explained here => http://www.commandlinefu.com/commands/view/13). By default bash immediately executes the history command. Setting this shell option will make bash first allow you to verify/edit an history command before executing it. To set this option permanently, put this command in ~/.profile or ~/.bashrc file. To unset this option issue following command. $shopt -u histverify

Display the standard deviation of a column of numbers with awk

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

easily strace all your apache processes
This version also attaches to new processes forked by the parent apache process. That way you can trace all current and *future* apache processes.

pretend to be busy in office to enjoy a cup of coffee
This will turn it in an infinite loop and also shows random words from a file, so it won't be the same each time and also not just a number.

which program is this port belongs to ?
Sometimes you need to use a port that is already opened by some program , and you don't know who to "kill" for it to release - so, now you do !

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

grep tab chars
mixing tabs and spaces for indentation in python would confuse the python interpreter, to avoid that, check if the file has any tab based indentation. "^V" => denotes press control + v and press tab within quotes. $ cat improper_indent.py class Tux(object): print "Hello world.." $ grep " " improper_indent.py print "Hello world.."

create random string from /dev/urandom (or another length)

Creating ISO Images from CDs/DVDs
create an iso from your cd/dvd-rom device . You need to umount /dev/cdrom before using the cli


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: