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

Copy a file and force owner/group/mode
This is useful when you want to copy a file and also force a user, a group and a mode for that file. Note: if you want to move that file instead of copying it, you can use $install -o user -g group -m 755 /path/to/file /path/to/dir/ && rm -f /path/to/file which will remove the file only if the install command went fine.

Time conversion/format using the date command

Google Translate
substitute "example" with desired string; tl = target language (en, fr, de, hu, ...); you can leave sl parameter as-is (autodetection works fine)

Create an audio test CD of sine waves from 1 to 99 Hz
This command creates and burns a gapless audio CD with 99 tracks. Each track is a 30 second sine wave, the first is 1 Hz, the second 2 Hz, and so on, up to 99 Hz. This is useful for testing audio systems (how low can your bass go?) and for creating the constant vibrations needed to make non-Newtonian fluids (like cornstarch and water) crawl around. Note, this temporarily creates 500MB of .cdda files in the current directory. If you don't use the "rm" at the end of the command, you can burn more disks using $ cdrdao write cdrdao.toc Prerequisites: a blank CD-R in /dev/cdrw, sox (http://sox.sourceforge.net/), and cdrdao (http://cdrdao.sourceforge.net/). I'm also assuming a recent version of bash for the brace expansion (which just looks nicer than using seq(1), but isn't necessary).

Simplest way to get size (in bytes) of a file

Query an NFS host for its list of exports

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

listen to an offensive fortune
or replace "espeak" with "festival --tts" if you like festival better when your buddy leaves his computer unlocked use "crontab" or "at" to play at some time that would be most embarassing (during his next sales presentation) $ echo "fortune -o | espeak" | at now + 30 minutes of course you can exclude the "-o" for non offensive fortunes, or if you don't have offensive fortunes installed

Sort file greater than a specified size in human readeable format including their path and typed by color, running from current directory
1. find file greater than 10 MB 2. direct it to xargs 3. xargs pass them as argument to ls

Discover full java className for import;
If you want to code without a IDE, using java may be painful to discover correct full class names to import. This script google it with javadoc word, then with some luck we got the javadoc as first item. next it curl the target javadoc and extract full name from it. Can by customized to extract other javadoc infos. Pre-reqs: bash, google-chrome, html2text and core-utils


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: