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Print all lines between two line numbers
This command uses awk(1) to print all lines between two known line numbers in a file. Useful for seeing output in a log file, where the line numbers are known. The above command will print all lines between, and including, lines 3 and 6.

Sort lines using the Xth characted as the start of the sort string
Tells sort to ignore all characters before the Xth position in the first field per line. If you have a list of items one per line and want to ignore the first two characters for sorting purposes, you would type "sort -k1.3". Change the "1" to change the field being sorted. The decimal value is the offset in the specified field to sort by.

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"

send a circular

Monitor Linux/MD RAID Rebuild

Create/open/use encrypted directory
Create/open/use an encrypted directory encfs needs to be installed During creation easiest to use default values The encrypted files will be in ~/.crypt and you will work as usual in ~/crypt To close the encrypted directory run: fusermount -u ~/crypt When you switch off the computer the encrypted directory will be automatically closed This example uses /home/user/crypt as encrypted directory I use ubuntu linux 8.04 and I am also the creator of www.minihowto.org

determine if tcp port is open

Find the package that installed a command

Kill all Zombie processes if they accept it!
Tested on FreeBSD 8.1 and CSH. The scripts works correctly but the Zombies do not die! I hope it will run and function as expected in Linux and others.

Remove duplicate lines whilst keeping empty lines and order
Remove duplicate lines whilst keeping order and empty lines


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