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Tricky implementation of two-dimensional array in Bash.
Since Bash doesn't support two-dimensional arrays, you can limit your columns length by some big enough constant value ( in this example 100 ) and then index the array with i and j, or maybe write your own get() and set() methods to index the array properly like I implemented for example ( see Sample output ). For example for i=0 and j=0...99 you'll pick up one of 100 elements in the range [0,99] in the one-dimensional array. For i=1 and j=0...99 you'll pick up one of 100 elements in the range [100,199]. And so on. Be careful when using this, and remember that in fact you are always using one-dimensional array.

Convert a string to

SED - Substitute string in next line
source: http://sed.sourceforge.net/sed1line.txt

Get a list of ssh servers on the local subnet
Scan the local network for servers who have the ssh port open.

Complete TCP Handshake on a given host-port
Try to perform a fully TCP 3 way handshake on for a given host-port with a timeout of 1s.

check open ports without netstat or lsof

Which fonts are installed?
See all fonts installed in your system

Clean up poorly named TV shows.
Replace 'SHOWNAME' with the name of the TV show. Add -n to test the command without renaming files. Check the 'sample output'.

Best option set for 7zip compression of database dumps or generic text files
These re the best option combination that works fine for compressing my database dumps. It's possible that there are another option or value that might improve the compression ratio, by these are the ones that worked, the syntax for 7zr it's a little messy...

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.


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