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

list files recursively by size

Alias for quick command-line volume set (works also remotely via SSH)
If you're addicted to command-line solutions of ordinary actions or if you just want to set your volume from bed via mobile phone SSH, you can set this alias and use it as $ setvol 50 for setting volume on 50% gain Works only with ALSA, tested on Ubuntu 8.10. Give me some info about your experience. TIP: Try aslo command "mute" to toggle mute/unmute sound. But I don't know if this works on all distros.

find and delete empty dirs, start in current working dir
A quick way to find and delete empty dirs, it starts in the current working directory. If you do find . -empty -type d you will see what could be removed, or to a test run.

Update twitter via curl
Doesn't require password (asks for it instead)

Command to logout all the users in one command
Logs all users out except root. I changed the grep to use a regexp in case a user's username contained the word root.

Create a random file of a specific size
This will create a 10 MB file named testfile.txt. Change the count parameter to change the size of the file. As one commenter pointed out, yes /dev/random can be used, but the content doesn't matter if you just need a file of a specific size for testing purposes, which is why I used /dev/zero. The file size is what matters, not the content. It's 10 MB either way. "Random" just referred to "any file - content not specific"

Change every instance of OLD to NEW in file FILE
Very quick way to change a word in a file. I use it all the time to change variable names in my PHP scripts (sed -i 's/$oldvar/$newvar/g' index.php)

Quickly analyse an Apache error log
This searches the Apache error_log for each of the 5 most significant Apache error levels, if any are found the date is then cut from the output in order to sort then print the most common occurrence of each error.

a for loop with filling 0 format, with seq
seq allows you to format the output thanks to the -f option. This is very useful if you want to rename your files to the same format in order to be able to easily sort for example: $for i in `seq 1 3 10`; do touch foo$i ;done And $ls foo* | sort -n foo1 foo10 foo4 foo7 But: $for i in `seq -f %02g 1 3 10`; do touch foo$i ;done So $ls foo* | sort -n foo01 foo04 foo07 foo10

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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: