Commands by jaymcgavren (2)

  • Purely frivolous - print a sine/cosine curve to the console - the width varies as it progresses. Ctrl-C to halt. Show Sample Output


    9
    ruby -e "i=0;loop{puts ' '*(29*(Math.sin(i)/2+1))+'|'*(29*(Math.cos(i)/2+1)); i+=0.1}"
    jaymcgavren · 2010-03-09 06:21:29 6
  • Use Ruby's standard Curses module to display a Lissajous curve in the console. Replace the "0.2" with different numbers for different curves. Show Sample Output


    2
    ruby -rcurses -e"include Curses;i=0;loop{setpos 12*(Math.sin(i)+1),40*(Math.cos(i*0.2)+1);addstr'.';i+=0.01;refresh}"
    jaymcgavren · 2010-03-09 06:10:47 14

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

Synchronise a file from a remote server
You will be prompted for a password unless you have your public keys set-up.

Remote screenshot
The `export` is unnecessary if it's only applicable to the one command.

Shows what processes need to be restarted after system upgrade
emerge,apt-get,yum... all update your system. This will at some point replace either a runtime dependency or a process (which is still running). This oneliner will list what processes need to be restarted

check open ports without netstat or lsof

Extract track 9 from a CD
Using mplayer to extract audio file from a CD

git remove files which have been deleted
I've used technicalpickles command a lot, but this one handles whitespaces in filenames. I'm sure you want to create an alias for it :)

Increase mplayer maximum volume
use '0' and '9' to increase/decrease volume. this is useful on laptops with low speaker volume.

play audio stream and video stream in two different mplayer instances
Sometimes audio and video are not sync'ed. The factor 1.0884 is the quotient 48000/44100. One mplayer plays the audio file in the background, the other the video in the foreground. You can dump the audio file before with another commandlinefu

find external links in all html files in a directory list
Just a handy way to get all the unique links from inside all the html files inside a directory. Can be handy on scripts etc.

Create a false directory structure for testing your commands
This will make a false directory with the same file names as whatever directory you choose. This is wise to use when testing scripts that alter contents, filenames, or move files. I wrote this after an OOPS I made when renaming a directory of JPGs, PNGs, PSDs that were mixed. I recommend this as I lost over 2000 vacation pictures and some graphics I designed for software and web sites. :( NOTE: This only creates name copies, that data itself is not copied.


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: