Commands by Vasudev (4)

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April Fools' Day Prank
Add this to a fiend's .bashrc. PROMPT_COMMAND will run just before a prompt is drawn. RANDOM will be between 0 and 32768; in this case, it'll run about 1/10th of the time. \033 is the escape character. I'll call it \e for short. \e7 -- save cursor position. \e[%d;%dH -- move cursor to absolute position \e[4%dm \e[m -- draw a random color at that point \e8 -- restore position.

Search for classes in Java JAR files.

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"

Updating the status on identi.ca using curl.
identica is an open source social networking and micro-blogging service. Based on Laconica, a micro-blogging software package built on the OpenMicroBlogging specification. http://identi.ca/

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" }

Scale,Rotate, brightness, contrast,...with Image Magick
$rotate: the rotate angle $width, $height: width and height to scale to $birghtness: change brighness

umount --rbind mount with submounts
Original: https://bugzilla.redhat.com/show_bug.cgi?id=194342

Display which distro is installed
Works on nearly all linux distros

Mount proc
Run this in / in a chroot to get your own proc there.

Quickly generate an MD5 hash for a text string using OpenSSL


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