Commands by greppo (3)

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

Continually monitor things
You can use this one-liner for a quick and dirty (more customizable) alternative to the watch command. The keys to making this work: everything exists in an infinite loop; the loop starts with a clear; the loop ends with a sleep. Enter whatever you'd like to keep an eye on in the middle.

Convert text to lowercase
Usage: lower [STRING]...

Stat each file in a directory
Possible simplification of egrep-awk-sort with find and -exec with xargs.

Write a shell script that removes files that contain a string
Deletes files in the current directory or its subdirectories that match "regexp" but handle directories, newlines, spaces, and other funky characters better than the original #13315. Also uses grep's "-q" to be quiet and quit at the first match, making this much faster. No need for awk either.

check open ports without netstat or lsof

Rename files in batch

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

Create and play an instant keyword based playlist
It works best as part of a function, such as the following: MUSICROOT=~/Music function fplay { if [ $1 = '-v' ]; then shift 1 find -E $MUSICROOT -type f -iname "*$**" -iregex '.*\.(3g[2|p]|aac|ac3|adts|aif[c|f]?|amr|and|au|caf|m4[a|r|v]|mp[1-4|a]|mpeg[0,9]?|sd2|wav)' -print -exec afplay "{}" \; & else find -E $MUSICROOT -type f -iname "*$**" -iregex '.*\.(3g[2|p]|aac|ac3|adts|aif[c|f]?|amr|and|au|caf|m4[a|r|v]|mp[1-4|a]|mpeg[0,9]?|sd2|wav)' -exec afplay "{}" \; & fi }

Upgrade all expired homebrew packages
You probably want to run `brew update` before you run this command

Output as many input
Output of a command as input to many


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: