Commands by mnikhil (27)

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Capture video of a linux desktop
This is identical to the original command, but allows you to specify an offset if you have multiple monitors. In this case you'll record a 1366x768 window that's offset by 1366 pixels in the x axis and 0 pixels in the y axis. Note also that the -sameq option has been replaced by -qscale - at least in ffmpeg version 1.2.1 on Fedora 19.

List all TCP opened ports on localhost in LISTEN mode
Alternative of OJM snippet : This one show the IP too, where ports bind. It's very important, because if there's only 127.0.0.1 instead of 0.0.0.0, connections from internet are rejected.

Count number of files in subdirectories
For each directory from the current one, list the counts of files in each of these directories. Change the -maxdepth to drill down further through directories.

Numerically sorted human readable disk usage
Provides numerically sorted human readable du output. I so wish there was just a du flag for this.

Test file system performance
You need bonnie++ package for this. More detail than a simple hdparm -t /dev/sda would give you. the -d is the directory where it performs writes/reads for example I use /tmp/scratch with 777 permissions Bonnie++ benchmarks three things: data read and write speed, number of seeks that can be performed per second, and number of file metadata operations that can be performed per second.

use vim to get colorful diff output
:q to quit

Add line number count as C-style comments
I often find the need to number enumerations and other lists when programming. With this command, create a new file called 'inputfile' with the text you want to number. Paste the contents of 'outputfile' back into your source file and fix the tabbing if necessary. You can also change this to output hex numbering by changing the "%02d" to "%02x". If you need to start at 0 replace "NR" with "NR-1". I adapted this from http://osxdaily.com/2010/05/20/easily-add-line-numbers-to-a-text-file/.

Url Encode
Converts reserved characters in a URI to their percent encoded counterparts. Alternate python version: $ echo "$url" | python -c 'import sys,urllib;print urllib.quote(sys.stdin.read().strip())'

Convert a videos audio track to ogg vorbis.
Assumes you have ffmpeg and oggenc. Similar to other scripts here, but this time outputting to Ogg Vorbis. I added the variable assignment for a nice output name. This is part of an interactive bash script I have with a few little multimedia tasks in it. http://www.dward.us/software/VSAK.sh

Start another X session in a window
You might have Xnest (older) rather than Xephyr. You can experiment with other desktops eg: startx /usr/bin/start-kde -- /usr/bin/Xephyr :2 You can start X on a remote machine (although I'd recommend vnc for anything slower than a LAN): startx /usr/bin/ssh -X gnome-session -- /usr/bin/Xephyr :2 Or just start another X session locally talking to the remote backend:


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