Commands by lajarre (1)

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Find usb device in realtime
Using this command you can track a moment when usb device was attached.

DVD ripping with ffmpeg
To rip DVD movie to ogg format using ffmpeg, follow these steps. 1) find the vob files on the mounted video DVD in VIDEO_TS that stores the movie itself. There would be a few other VOB files that stores splash screen or special features, the vob files for the movie itself can be identified by its superior size. You can verify these vob files by playing them directly with a player (e.g. mplayer) 2) concatenate all such vob files, pipe to ffmpeg 3) calculate the video size and crop size. The ogg video size must be multiple of 16 on both width and height, this is inherit limitation of theora codec. In my case I took 512x384. The -vcodec parameter is necessary because ffmpeg doesn't support theora by itself. -acodec is necessary otherwise ffmpeg uses flac by default.

Creating ISO Images from CDs/DVDs
create an iso from your cd/dvd-rom device . You need to umount /dev/cdrom before using the cli

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"

What is my ip?

Given $PID, print all child processes on stdout
Simpler.

Share your terminal session (remotely or whatever)
Force the user you want to watch doing things into doing his things in a screen session. Then simply attach yourself to that session with the command shown above. Works only if you are on the same machine, of course

Diff files over SSH
Sometimes you need to compare two config files on different servers. Put the file names into the above script and let 'er rip.

Takes all file except file between !()
Go to tmp : cd /tmp; mkdir retmp; cd retmp Create 10 files : for i in {1..10}; do touch test$i; done Remove all files except test10 : rm !(test10)

Puts every word from a file into a new line
Basically it creates a typical word list file from any normal text.

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