Commands by Glip (1)

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

grep (or anything else) many files with multiprocessor power
xargs -P N spawns up to N worker processes. -n 40 means each grep command gets up to 40 file names each on the command line.

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"

cleanup /tmp directory
Cleans all files in /tmp that have been accessed at least 2 days ago.

Convert PDF to JPG
(relies on 'imagemagick') This command will convert all .pdf files in a directory into a 800px (wide or height, whichever is smaller) image (with the aspect ratio kept) .jpg. If the file is named 'example1.pdf' it will be named 'example1.jpg' when it is complete. This is a VERY worthwhile command! People pay hundreds of dollars for this in the Windows world. My .jpg files average between 150kB to 300kB, but your's may differ.

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

Facebook Email Scraper
(Apparently it is too long so I put it in sample output, I hope that is OK.) Run the long command (or put it in your .bashrc) in sample output then run: $ fbemailscraper YourFBEmail Password Voila! Your contacts' emails will appear. Facebook seems to have gotten rid of the picture encoding of emails and replaced it with a text based version making it easy to scrape! Needs curl to run and it was made pretty quickly so there might be bugs.

Convert diff output to HTML ins/del

Benchmark SQL Query
Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

use SHIFT + ALT to toggle between two keyboard layouts
change the last two-character abbreviation to any layout abbreviation you want. This command will only run in the current session, add to your ~/.bashrc to make this permanent.

Live stream a remote desktop over ssh using only ffmpeg
Play with the framerate option '-r' to scale back bandwidth usage. The '-s' option is the captured screan area, not the rescaled size. If you want to rescale add a second '-s' option after '-i :0'. Rescaling smaller will also decrease bandwidth.


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: