Commands by rsimpson (3)

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

a function to create a box of '=' characters around a given string.
The function 'box' takes either one or two arguments. The first argument is a line of text to be boxed, the second argument (optional) is a character to use to draw the box. By default, the drawing character will be '='. The function 'n()' is a helper function used to draw the upper and lower lines of the box, its arguments are a length, and an character to print. (I used 'n' because 'line', 'ln' and 'l' are all commonly used)

Get your external IP address ( 10 characters long )
Shortest url to a external IP-service, 10 characters.

Check if your ISP is intercepting DNS queries
It's somewhat common ISPs to intercept DNS queries at port 53 and resolve them at their own. To check if your ISP is intercepting your DNS queries just type this command in the terminal. "#.abc" it's an OK answer. But if you get something like "I am not an OpenDNS resolver.", yep, you are beign cheated by your ISP.

Play 89.3 @TheCurrent and get system notifications on song changes.
Plays the mp3 stream of The Current as a background job. When you are done run: $ fg %1 then to exit Quite possible with Growl for mac I'd guess, although have not tried. Libnotify needed for notification, stream will still work otherwise

Remove all but one specific file

Limit memory usage per script/program
When I'm testing some scripts or programs, they end up using more memory than anticipated. In that case, computer nearly halts due to swap space usage, and sometimes I have to press Magic SysRq+REISUB to reboot. So, I was looking for a way to limit memory usage per script and found out that ulimit can limit memory. If you run it this way: $ $ ulimit -v 1000000 . $ $ scriptname Then the new memory limit will be valid for that shell. I think changing the limit within a subshell is much more flexible and it won't interfere with your current shell ulimit settings. note: -v 1000000 corresponds to approximately 1GB of RAM

Command for JOHN CONS
Would create a file with a meaningful title. Dedicated to John Cons, who is annoying us users. Merry Christmas!!!

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

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.


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