Commands by rackerjack (1)

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wget download with multiple simultaneous connections

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

merge multiple jpgs to one picture vertikal
# convert tool is from deb imagemagick-6.q16 apt install imagemagick-6.q16

Salvage a borked terminal
Also works in places where reset does not.

do 'foo' until it exits successfully, pausing in between crashes
restart a buggy script when it dies. works great for "git svn fetch", which leaks memory like a sieve and eventually dies...making you restart it.

Manually Pause/Unpause Firefox Process with POSIX-Signals
Continue with: $killall -CONT -m firefox Suspends all Firefox Threads. Results in Zero CPU load. Useful when having 100+ Tabs open and you temporarily need the power elsewhere. Be careful - might produce RACE CONDITIONS or LOCKUPS in other processes or FF itself. matching is case sensitive.

Are there any words in the English language that use at least half of the alphabet without repeating any letters?
This is the most straightforward approach: first regexp limits dictionary file to words with thirteen or more characters, second regexp discards any words that have a letter repeated. (Bonus challenge: Try doing it in a single regexp!)

Add a GPL license file to your project

Squish repeated delimiters into one
This can be particularly useful used in conjunction with a following cut command like $echo "hello::::there" | tr -s ':' | cut -d':' -f2 which prints 'there'. Much easier that guessing at -f values for cut. I know 'tr -s' is used in lots of commands here already but I just figured out the -s flag and thought it deserved to be highlighted :)

Image to color palette generator
Extract a color palette from a image useful for designers. Example usage: $extract-palette myawesomeimage.jpg 4 Where the first argument is the image you want to extract a palette from. The second argument is the number of colors you want. It may be the case where you want to change the search space. In that case, change the -resize argument to a bigger or smaller result. See the ImageMagick documentation for the -resize argument.

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