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Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

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"

mean color of an image
You can get the mean value for the colours in an image. Then you can determine, in general, how dark or bright is the image and run some other actions based on that. I'll recommend to readjust the brightness of the images using +sigmoidal-contrast option of imagemagick convert command.

Generate Random Text based on Length

Delete files older than..
This command will delete files i a given path (/dir_name) , which older than given time in days (-mtime +5 will delete files older than five days.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

tell if a port is in use
if you don't do --numeric-ports, netstat will try to resolve them to names

List the size of all sub folders and files from the current location, with sorting

Upload folder to imageshack.us (forum)
Each file in the current folder is uploaded to imageshack.us If the folder contains other filetypes change: $for files in * to: $for files in *.jpg (to upload ONLY .jpg files) Additionally you can try (results may vary): $for files in *.jpg *.png The output URL is encased with BB image tags for use in a forum.

Generate map of your hardware


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