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

Speed up builds and scripts, remove duplicate entries in $PATH. Users scripts are oftern bad: PATH=/apath:$PATH type of thing cause diplicate.

pattern match in awk - no grep
Rather than chain a string of greps together and pipe them to awk, use awk to do all the work. In the above example, a string would be output to stdout if it matched pattern1 AND pattern2, but NOT pattern3.

list block devices
Shows all block devices in a tree with descruptions of what they are.

find all active IP addresses in a network
You send a unicast ICMP packet to each host. Many firewalls will drop that ICMP. However, in order to send the ICMP, you'll have first done an ARP request and the remote machine is unlikely to ignore that, so the computer will be in your ARP table.

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

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

Download all manuals RedHat 7 (CentOS/Fedora) with one command in Linux

Find Duplicate Files (based on MD5 hash)
Calculates md5 sum of files. sort (required for uniq to work). uniq based on only the hash. use cut ro remove the hash from the result.

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

checking space availabe on all /proc/mounts points (using Nagios check_disk)
More info here: http://nagioswiki.com/wiki/index.php/Checking_/proc/mounts_on_remote_server


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: