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Search for a process by name
ps and grep is a dangerous combination -- grep tries to match everything on each line (thus the all too common: grep -v grep hack). ps -C doesn't use grep, it uses the process table for an exact match. Thus, you'll get an accurate list with: ps -fC sh rather finding every process with sh somewhere on the line.

Generat a Random MAC address
Original author unknown (I believe off of a wifi hacking forum). Used in conjuction with ifconfig and cron.. can be handy (especially spoofing AP's)

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"

Fetch every font from dafont.com to current folder
Requires aria2c but could just as easily wget or anything else. A great way to build up a nice font collection for Gimp without having to waste a lot of time. :-)

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

GRUB2: set Super Mario as startup tune
I'll let Slayer handle that. Raining Blood for your pleasure.

convert pdf into multiple png files
syntax for resolution is: (see "man gs" for further informations) -rnumber -rnumber1xnumber2

clean up syntax and de-obfuscate perl script
the command show can be run in vim, here is the same thing on the command line $ cat script.pl | perl -MO=Deparse | perltidy

Convert PDF to JPG
(relies on 'imagemagick') This command will convert all .pdf files in a directory into a 800px (wide or height, whichever is smaller) image (with the aspect ratio kept) .jpg. If the file is named 'example1.pdf' it will be named 'example1.jpg' when it is complete. This is a VERY worthwhile command! People pay hundreds of dollars for this in the Windows world. My .jpg files average between 150kB to 300kB, but your's may differ.

Close specify detached screen
-X Send the specified command to a running screen session. -S Option to specify the screen session if you have several screen sessions running. $screen -ls for listing current screens and its sessionname


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