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Check if a command is available in your system
Usefull to detect if a commad that your script relies upon is properly installed in your box, you can use it as a function function is_program_installed() { type "$1" >/dev/null } Invoke it and check the execution code is_program_installed "dialog" if [ ! $? -eq 0 ]; then echo "dialog is not installed" exit 1 fi

Grab the first 3 octets of your ip addresses
For machines that have many ip blocks spanning different Class C's, this will show which ones.

find listening ports by pid
change 24073 to your pid

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"

Using ASCII Art output on MPlayer
Not so useful. Just a cool feature.

generate random password
for Mac OS X

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Create an SSH SOCKS proxy server on localhost:8000 that will re-start itself if something breaks the connection temporarily
This command will log you into somehost via SSH and then go into the background (-f). From there, you can point e.g. firefox at localhost:8000 as a SOCKS proxy. Autossh will use port 20000 and 20001 to send and receive test data on those ports to ensure the SSH tunnel is still running, and will try to re-start the tunnel if it goes down. Make sure you have ssh-agent running, or passwordless ssh keys distributed between the two hosts.

Another Matrix Style Implementation

Show how old your linux OS installtion is
..not guaranteed to always be accurate but fun to see how old you Linux installation is based on the root partitions file system creation date.


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