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Perform a branching conditional
This will perform one of two blocks of code, depending on the condition of the first. Essentially is a bash terniary operator. To tell if a machine is up: $ ping -c1 machine { echo succes;} || { echo failed; } Because of the bash { } block operators, you can have multiple commands $ ping -c1 machine && { echo success;log-timestamp.sh }|| { echo failed; email-admin.sh; } Tips: Remember, the { } operators are treated by bash as a reserved word: as such, they need a space on either side. If you have a command that can fail at the end of the true block, consider ending said block with 'false' to prevent accidental execution

Text message on wallpaper
Display some text on the wallpaper especially warning messages

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"

Create a tar of directory structure only
The original suggestion did not work for me, when operating on folders located on an external mount (ie other than the root device) in Ubuntu. A variation using xargs does the trick.

Deleting / Ignoring lines from the top of a file

Join flv files

Geolocate a given IP address

Add calendar to desktop wallpaper
Add calendar to desktop wallpaper , mess with the coordinates to place where you like

Delete only binary files in a directory
Please note that binary file checking is NOT perfect. So, use it with caution. It does not delete hidden files whose name has a leading '.' character. And it regards an empty file as a binary file.

list block devices
Shows all block devices in a tree with descruptions of what they are.


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