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

Automagically update grub.conf labels after installing a new kernel
I like to label my grub boot options with the correct kernel version/build. After building and installing a new kernel with "make install" I had to edit my grub.conf by hand. To avoid this, I've decided to write this little command line to: 1. read the version/build part of the filename to which the kernel symlinks point 2. replace the first label lines of grub.conf grub.conf label lines must be in this format: Latest [{name}-{version/build}] Old [{name}-{version/build}] only the {version/build} part is substituted. For instance: title Latest [GNU/Linux-2.6.31-gentoo-r10.201003] would turn to title Latest [GNU/Linux-2.6.32-gentoo-r7.201004]"

print/scan lines starting at record ###
Useful for finding newly added lines to a file, tail + can be used to show only the lines starting at some offset. A syslog scanner would look at the file for the first time, then record the end_of_file record number using wc -l. Later (hours, days), scan only at the lines that were added since the last scan.

remove password from openssl key file
Strip a password from a openssl key to use with apache httpd server

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

Install pip with Proxy
Installs pip packages defining a proxy

New Maintainer for CommandLineFu
Welcome to Jon H. (@fart), the new maintainer of CommandLineFu. . In the absence of a forum, I encourage people welcome him, here, in the comments. . Also... What would you like to improve/change about the site?

shell bash iterate number range with for loop

Kill multiple instances of a running process

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"

delete a particular line by line number in file
deletes line 3 in known_hosts text file


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: