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

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"

Shows cpu load in percent
Show the current load of the CPU as a percentage. Read the load from /proc/loadavg and convert it using sed: Strip everything after the first whitespace: $ sed -e 's/ .*//' Delete the decimal point: $ sed -e 's/\.//' Remove leading zeroes: $ sed -e 's/^0*//'

Convert spaces in file names to underscores

Find brute force attempts on SSHd
Searches the /var/log/secure log file for Failed and/or invalid user log in attempts.

This allows you to find a string on a set of files recursivly
The -r is for recursive, -F for fixed strings, --include='*.txt' identifies you want all txt files to be search any wildcard will apply, then the string you are looking for and the final * to ensure you go through all files and folders within the folder you execute it.

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"

Extract tarball from internet without local saving

Send test prints to networked printer.
This will send a test print job to a networked printer.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

IFS - use entire lines in your for cycles
When you use a "for" construct, it cycles on every word. If you want to cycle on a line-by-line basis (and, well, you can't use xargs -n1 :D), you can set the IFS variable to .


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: