Commands by JeffChen (1)

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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" }

Print the 10 deepest directory paths

Increase mplayer maximum volume
use '0' and '9' to increase/decrease volume. this is useful on laptops with low speaker volume.

Check the current price of Bitcoin in USD

Kills a process that is locking a file.
Useful when you're trying to unmount a volume and other sticky situations where a rogue process is annoying the hell out of you.

copy with progress bar - rsync
-r for recursive (if you want to copy entire directories) src for the source file (or wildcards) dst for the destination --progress to show a progress bar

Pass TAB as field separator to sort, join, cut, etc.
Use this BASH trick to create a variable containing the TAB character and pass it as the argument to sort, join, cut and other commands which don't understand the \t notation. $ sort -t $'\t' ... $ join -t $'\t' ... $ cut -d $'\t' ...

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"

Have a random "cow" say a random thing
You need to have fortune and cowsay installed. It uses a subshell to list cow files in you cow directory (this folder is default for debian based systems, others might use another folder). you can add it to your .bashrc file to have it great you with something interesting every time you start a new session.

Rotate a video file by 90 degrees CW


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