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

Displays the current time using HTTP
This command will show the current GMT time using HTTP. This might be useful if you just want to know what's the current human-readable and accurate-enough time, without changing the system time, using a simple command that would work regardless of the availability of NTP. Note: To get a quicker and more accurate response, replace google.com with your local NTP server. Also can be used as an alternative to the "htpdate" program: http://www.commandlinefu.com/commands/view/668/set-your-computers-clock-using-http-and-htp-http-time-protocol-when-ntpsntp-is-not-available

iso to USB with dd and show progress status
need package: pv apt-get install pv get the iso size in byte with ls -l install-cd.iso /dev/sdb is your USB Device (without partitionNr.)

flip faster and more precisely through commands saved in history
flip shell history with PG UP/PG DOWN like with arrows. just type ss and PG UP and see all ssh commands, type ls and PG DOWN - see all ls commands. need to uncomment two options in /etc/inputrc: "\e[5~": history-search-backward "\e[6~": history-search-forward hack found: http://broddlit.wordpress.com/2008/04/12/making-the-bash-history-a-better-place/

Scan Network for Rogue APs.
I've used this scan to sucessfully find many rogue APs on a very, very large network.

Find common groups between two users

Using tput to save, clear and restore the terminal contents
Very useful for interactive scripts where you would like to return the terminal contents to its original state before the script was run. This would be similar to how vi exits and returns you to your original terminal screen. Save and clear the terminal contents with: $tput smcup Execute some commands, then restore the saved terminal contents with: $tput rmcup

Save a file you edited in vim without the needed permissions
Calls sudo tee like all the other lines, but also automatically reloads the file. Optionally you can add command Wq :execute ':W' | :q and command WQ :Wq to make quitting easier

Do some learning...
no loop, only one call of grep, scrollable ("less is more", more or less...)

Automatic ssh Session Logger
A wrapper around ssh to automatically provide logging and session handling. This function runs ssh, which runs screen, which runs script. . The logs and the screen session are stored on the server. This means you can leave a session running and re-attach to it later, or from another machine. . . Requirements: * Log sessions on a remote server * Transparent - nothing extra to type * No installation - nothing to copy to the server beforehand . Features: * Function wrapper delegating to ssh - so nothing to remember - uses .ssh/config as expected - passes your command line option to ssh * Self-contained: no scripts to install on the server * Uses screen(1), so is: - detachable - re-attachable - shareable * Records session using script(1) * Configurable log file location, which may contain variables or whitespace L="$HOME" # local variable L="\$HOME" # server variable L="some space" . Limitations: * Log dir/file may not contain '~' (which would require eval on the server) . . The sessions are named by the local user connecting to the server. Therefore if you detach and re-run the same command you will reconnect to your original session. If you want to connect/share another's session simply run: $ USER=bob ssh root@server . The command above is stripped down to an absolute minimum. A fully expanded and annotated version is available as a Gist (git pastebin): https://gist.github.com/flatcap/3c42326abeb1197ee714 . If you want to add timing info to script, change the command to: $ ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "$@" "mkdir -p \"${L%/*}\";screen -xRRS $USER script --timing=\"$L-timing\" -f \"$L\"";}

Delete all non-printing characters from a file
tr has some predefined sets of characters that are more convenient to use than characters codes


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: