Commands by Marius (1)

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Convert Shell Text to Upper/Lower Case

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"

Random IPv4 address

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.

Randomize lines in a file
shuf is in the coreutils package

Change gnome-shell wallpaper

list files recursively by size

Create a backup of file being edited while using vi
At the start of a vi session and *before* saving any changes use ":!cp % %-" to make a backup of the current file being edited. example: vi /data/some/long/path/file :!cp% %- creates /data/some/long/path/file-

Insert the last argument of the previous command
for example if you did a: $ ls -la /bin/ls then $ ls !$ is equivalent to doing a $ ls /bin/ls

Remove all zero size files from current directory (not recursive)


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