Commands by cfajohnson (19)

What's this? 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.

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Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

!* Tells that you want all of the *arguments* from the previous command to be repeated in the current command
Example: touch file{1,2,3}; chmod 777 !*

geoip lookup

Display a random crass ascii art from
Optionally, pipe the output into Or: wget -qO - | sed -n '//,//p' | sed -n '/

sort lines by length
making it "sound" more "natural" language like -- additionally sorting the longest words alphabetically: this approach is using: * to get at all lines of input * post-"for" structure * short-circuit-or in sort: if the lengths are the same, then sort alphabetically otherwise don't even evaluate the right hand side of the or * -C sets all input and ouput channels to utf8

Rename duplicates from MusicBrainz Picard
Renames duplicates from MusicBrainz Picard, so you get the latest copy and not a bunch of duplicates.

Show the UUID of a filesystem or partition
Shows the UUID of a filesystem or partition that can be used in kernel root options and in fstab. Run it without the -u option to generate more information. eg: ~/ sudo vol_id /dev/sda2 ID_FS_USAGE=other ID_FS_TYPE=swap ID_FS_VERSION=2 ID_FS_UUID=27fca13d-97b7-4d28-882c-6d03353f0a82 ID_FS_UUID_ENC=27fca13d-97b7-4d28-882c-6d03353f0a82 ID_FS_LABEL= ID_FS_LABEL_ENC=

Find default gateway (proper at ppp connections too)

Watch your freebox flux, through a other internet connection (for French users)
You can watch channels of your freebox, everywhere. With " vlc http://your-ip:12345 " on the client and ncurses vlc interface on the host. et voila

mplayer webcam window for screencasts
When recording screencast some people like to have the image from their webcam, so the can show something, that can't be seen on the desktop. So starting mplayer with these parameters you will have a window with no frames, borders whatsoever, and selecting the window a hitting the "F" key you will bring it in fullscreen. if you want to position the frame somewhere else, you could play with the --geomeptry option where 100%:100% mean bottom right corner. The HEIGHT and WIDTH can't be changed as you like, since the most webcams support specified dimensions, so you would have to play with it to see what is supported

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