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Signals list by NUMBER and NAME
This command seems to achieve the similar/same goal.

Find the package that installed a command

updatedb for MAC OSX
MAC OSX doesn't come with an updatedb command by default, this will emulate the updatedb thats on a typical Linux OS. Simply add it to your ~/.bash_profile

Execute a command with a timeout
In this example the command "somecommand" will be executed and sent a SIGALARM signal if it runs for more than 10 seconds. It uses the perl alarm function. It's not 100% accurate on timing, but close enough. I found this really useful when executing scripts and commands that I knew might hang E.g. ones that connect to services that might not be running. Importantly this can be used within a sequential script. The command will not release control until either the command completes or the timeout is hit.

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"

Combines an arbitrary number of transparent png files into one file
This one liner; combines all sequentially numbered files; in this example IMG_0001.png to IMG_1121.png by generating the shell script, making the shell script executable and then running the shell script to combine the 1121 png into a single png file named _final.png tested on Mac OS X 10.6.3 with ImageMagick 6.5.8-0 2009-11-22 Q16 http://www.imagemagick.org

extract email adresses from some file (or any other pattern)
This will catch most separators in the section of the email: dot . dash - underscore _ plus + (added for gmail) ... and the basic dash '-' of host names.

Resample a WAV file with sox
Change the sample rate with sox, the swiss army knife of sound processing.

Display BIOS Information

Rsync remote data as root using sudo
If your user has sudo on the remote box, you can rsync data as root without needing to login as root. This is very helpful if the remote box does not allow root to login over SSH (which is a common security restriction).


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