Commands by unixmonkey4063 (3)

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Check your bash shell for vulnerability to the ShellShock exploit
If this command prints 'x' then your shell is vulnerable. Null output confirms that you are protected. Further reading: http://allanmcrae.com/2014/09/shellshock-and-arch-linux/

Quickly batch resize images
-geometry (preserves values of height and width given, and aspect ratio). WARNING: While 'resize' creates resized copies of original files, 'mogrify' works on the original files, replacing them. It will overwrite the source files, use with caution, and backup regularly.

Returns the number of cores in a linux machine.
Original article in http://www.howtogeek.com/howto/ubuntu/display-number-of-processors-on-linux/

Apply, in parallel, a bc expression to CSV
Define a function that applies bc, the *nix calculator, with the specified expression to all rows of the input CSV. The first column is mapped to {1}, second one to {2}, and so forth. See sample output for an example. This function uses all available cores thanks to GNU Parallel. Requires GNU Parallel

Extract neatly a rar compressed file
It's also possible to delay the extraction (echo "unrar e ... fi" |at now+20 minutes) wich is really convenient!

Check if network cable is plugged in and working correctly
with 'mii-tool -w eth0' you can watch the interface for changes of the link status

Turns red the stderr output
Reference: http://stackoverflow.com/a/4455706

Turn shell tracing and verbosity (set -xv) on/off with 1 command!
Running this command turns shell tracing and shell verbose debugging on or off. Not only does it do that, it also uses your terminals builtin method of setting colors to make debugging much easier. It looks at the current shell options contained in the $- special bash variable and that lets this function set the opposite of the current value. So from the shell you could do a: $ setx; echo "y" | ( cat -t ) | echo "d"; setx and it will turn on debbuggin. This is an amazingly useful function that is perfect to add system-wide by adding it to /etc/profile or /etc/bashrc.. You can run it from the shell, and you can also use it in your shell scripts like my .bash_profile - http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

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

A fun thing to do with ram is actually open it up and take a peek. This command will show you all the string (plain text) values in ram

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