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

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Virtual Console lock program
vlock command locks the current console by default. Also you can lock all the consoles on the server by using -a parameter. For details, pl man vlock. ps: Generally speaking , system will not install vlock programme . So you should use ' $ sudo apt-get install vlock ' to install vlock .

Create backup copy of file, adding suffix of the date of the file modification (NOT today's date)
When I go to change a configuration file I always like to make a backup first. You can use "cp -p" to preserve the modification time, but it gets confusing to have file.prev, file.prev2, etc. So I like to add a YYMMDD suffix that shows when the file was last changed. "stat -c %Y" gives you the modification time in epoch seconds, then "date -d @" converts that to whatever format you specify in your "+format" string.

Calculate sum of N numbers (Thanks to flatcap)

Use result of the last command
\$ which python /usr/bin/python \$ ll `!!` lrwxrwxrwx 1 root root 9 2010-11-08 22:01 /usr/bin/python -> python2.6

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

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"

Debug how files are being accessed by a process
Instead of looking through `lsof` results, use inotifywait!

Stores the certificate expiration date on the variable A
Stores the certificate expiration date on the variable A

Capture video of a linux desktop
This is identical to the original command, but allows you to specify an offset if you have multiple monitors. In this case you'll record a 1366x768 window that's offset by 1366 pixels in the x axis and 0 pixels in the y axis. Note also that the -sameq option has been replaced by -qscale - at least in ffmpeg version 1.2.1 on Fedora 19.


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: