Commands by michelem (7)

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

Install pip with Proxy
Installs pip packages defining a proxy

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"

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Find duplicate UID in /etc/passwd
You can use only awk

guitar synthesizer in one line of C
outputs a f=220Hz guitar string sound (fifth string A) needs ALSA

Create incremental snapshots of individual folders using find and tar-gzip
Creates an incremental snapshot of individual folders.

Find top 10 largest files in /var directory (subdirectories and hidden files included )
Same as above, but modified to show human readable output

Get MD5 checksum from a pipe stream and do not alter it

Format date/time string for a different day
The "date' command has options to easily format the date, day, month, time, etc. But what if you want a relative date or time. Like, I wanted yesterday's date in a particular format. You may want the exact date of "2 months ago" or "-3 days" nicely formatted. For that, you can use this command. The --date option takes fuzzy parameters like the ones mentioned in the previous sentence.

resize all JPG images in folder and create new images (w/o overwriting)
Convert all jpegs in the current directory into ~1024*768 pixels and ~ 150 KBytes jpegs


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: