Commands using read (340)

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Calculate the distance between two geographic coordinates points (latitude longitude)
The Haversine formula determines the great-circle distance between two points on a sphere given their longitudes and latitudes.

get newest jpg picture in a folder
search the newest *.jpg in the directory an make a copy to newest.jpg. Just change the extension to search other files. This is usefull eg. if your webcam saves all pictures in a folder and you like the put the last one on your homepage. This works even in a directory with 10000 pictures.

See system users

Create a new file

Uniquely (sort of) color text so you can see changes
Colorify colors input by converting the text to a number and then performing modulo 7 on it. This resulting number is used as the color escape code. This can be used to color the results of commands with complex outputs (like "482279054165371") so if any of the digits change, there's a good chance the color will change too. I say good chance because there's only 7 unique colors here, so assuming you were watching random numbers, there would be a 6/7 chance that the color would change when the number changed. This should really only be used to help quickly identify when things change, but should not be the only thing relied upon to positively assert that an output has not changed.

Change the extension of a filename by using rename to convert
This will change all files ending in .JPG to .jpg and will work with any file extension

Check a server is up. If it isn't mail me.
Alternative to the ping check if your firewall blocks ping. Uses curl to get the landing page silently, or fail with an error code. You can probably do this with wget as well.

Countdown Clock
The biggest advantage over atoponce's nifty original is not killing the scrollback. Written assuming bash, but shouldn't be terribly difficult to port to other shells. S should be multiple spaces, but I can't get commandlinefu to save/show them properly, any help?

List all installed kernels on Ubuntu except current one
Lists all installed kernels minus the current one. This is useful to uninstall older kernels that take too much space on /boot partition.

Find the package that installed a command


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