Commands by DopeGhoti (3)

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Create an SSH connection (reverse tunnel) through your firewall.
Allows you to establish a tunnel (encapsulate packets) to your (Server B) remote server IP from your local host (Server A). On Server B you can then connect to port 2001 which will forward all packets (encapsulated) to port 22 on Server A. -- www.fir3net.com --

Real full backup copy of /etc folder
Yes, rsync(1) supports local directories. And, should anything change, it's trivial to run the command again, and grab only the changes, instead of the full directory.

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"

Get the date for the last Saturday of a given month
If your locale has Monday as the first day of the week, like mine in the UK, change the two $7 into $6

Invert selection with find.

Create an eicar.com test virus
Test whether real-time virus detection is working by running this command and checking for eicar.com in /tmp. Requires real-time scanning to be enabled and active on the /tmp directory. If scanning is active, the file should be quarantined/deleted (depending on your settings) moments after running this command. If not, the (harmless) test file should remain in your /tmp directory.

check open ports without netstat or lsof

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

Google Spell Checker
http://immike.net/blog/2007/04/07/hacking-google-spell-checker-for-fun-and-profit/

Command line calculator
This function defines a command line calculator that handles everything pythons math module can handle, e.g. trigonometric functions, sqrt, log, erf, ... (see http://docs.python.org/library/math.html). It even knows about the constants pi and e.


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