Commands by mobidyc (9)

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Delete all but latest file in a directory
Useful for deleting old unused log files.

Create a list of binary numbers
If you should happen to find yourself needing some binary numbers, this is a quickie way of doing it. If you need more digits, just add more "{0..1}" sequences for each digit you need. You can assign them to an array, too, and access them by their decimal equivalent for a quickie binary to decimal conversion (for larger values it's probably better to use another method). Note: this works in bash, ksh and zsh. For zsh, though, you'll need to issue a setopt KSH_ARRAYS to make the array zero-based. $ binary=({0..1}{0..1}{0..1}{0..1}) $ echo ${binary[9]}

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"

Compare copies of a file with md5
I had the problem that the Md5 Sum of a file changed after copying it to my external disk. This unhandy command helped me to fix the problem.

Lists the supported memory types and how much your board can support.

Sort files in folders alphabetically
Creates one letter folders in the current directory and moves files with corresponding initial in the folder.

List mp3 files with less than 320 kbps bitrate.

Zip each file in a directory individually with the original file name
This will list the files in a directory, then zip each one with the original filename individually. video1.wmv -> video1.zip video2.wmv -> video2.zip This was for zipping up large amounts of video files for upload on a Windows machine.

Make ls output better visible on dark terminals in bash
Sometimes you have a situation where you cannot properly see the ls output when you are using a terminal w/a dark background. Usually bash has ls aliased to use colors, and you can easily get ls to use the default foreground color via simply unaliasing the command.

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" }


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