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Define a quick calculator function
defines a handy function for quick calculations from cli. once defined: $ ? 10*2+3

The simplest way to transport information over a network
Einstein's razor: As simple as possible, but not simpler. On the destination machine netcat listens on any port (1234 in the example) and sends anything it receives into a file or pipe. On the source machine a separate netcat takes input from a file or pipe and sends it over the network to the listener. This is great between machines on a LAN where you don't care about authentication, encryption, or compression and I would recommend it for being simpler than anything else in this situation. Over the internet you should use something with better security.

Remove all mail in Postfix mail queue.

Display screen window number in prompt
Add this to your $HOME/.bashrc file. It will only set this prompt if it is running inside screen ($WINDOW var is set) Looks like this... $ ion@atomos:~[2]$

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"

Recurse through directories easily
This is a simple case of recursing through all directories, adding the '.bak' extension to every file. Of course, the 'cp $file $file.bak' could be any code you need to apply to your recursion, including tests, other functions, creating variables, doing math, etc. Simple and clean recursion.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

RDP through SSH tunnel
This command will: 1. open an SSH tunnel to 2. go to background 3. wait for 10 seconds for the connection 4. during the 10 seconds wait it will localy run 'rdesktop' to connect to the remote host through the created SSH tunnel. Password-less log in can be achieved (when server allows it) by adding '-p ' to the 'rdesktop' command

Get your outgoing IP address
should be very consistent cause it's google :-)

Remove \r (carriage return) in a file


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