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

find previously entered commands
Searches bash-history in reverse order (last entered commands first). Pressing ctrl+r again shows the next matching entry.

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.

Quickly create an alias for changing into the current directory
Put the function in your .bashrc and use "map [alias]" to create the alias you want. Just be careful to not override an existing alias.

List top 20 IP from which TCP connection is in SYN_RECV state
List top 20 IP from which TCP connection is in SYN_RECV state. Useful on web servers to detect a syn flood attack. Replace SYN_ with ESTA to find established connections

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

List all symbolic links in current directory
Tested with GNU and BSD ls.

move up through directories faster (set in your /etc/profile or .bash_profile)
You can also remove the "&& pwd" if you don't want it to print out each directory as it moves up.

To create files with specific permission:

Diff files on two remote hosts.

Create a directory and change into it at the same time
How often do you make a directory (or series of directories) and then change into it to do whatever? 99% of the time that is what I do. This BASH function 'md' will make the directory path then immediately change to the new directory. By using the 'mkdir -p' switch, the intermediate directories are created as well if they do not exist.


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: