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ShadyURL via CLI

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" }

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

function to verify an IP address - can be used at the shell prompt or in a shell script
When processing IP addresses in the shell (or shell script) it is useful to be able to verify that the value of data is an IP address (an not some random string or non-sensible IP address).

Paste OS X clipboard contents to a file on a remote machine
Redirects the contents of your clipboard through a pipe, to a remote machine via SSH.

add a gpg key to aptitute package manager in a ubuntu system
when we add a new package to a aptitude (the debian package manager) we need to add the gpg, otherwise it will show warning / error for missing key

Print ASCII Character Chart
Prints out an ascii chart using builtin bash! Then formats using cat -t and column. The best part is: $ echo -e "${p: -3} \\0$(( $i/64*100 + $i%64/8*10 + $i%8 ))"; From: http://www.askapache.com/linux/ascii-codes-and-reference.html

Clone perms and owner group from one file to another
Copy both perms and owner group from one file to another.

Give {Open,True}Type files reasonable names
Just a quick hack to give reasonable filenames to TrueType and OpenType fonts. I'd accumulated a big bunch of bizarrely and inconsistently named font files in my ~/.fonts directory. I wanted to copy some, but not all, of them over to my new machine, but I had no idea what many of them were. This script renames .ttf files based on the name embedded inside the font. It will also work for .otf files, but make sure you change the mv part so it gives them the proper extension. REQUIREMENTS: Bash (for extended pattern globbing), showttf (Debian has it in the fontforge-extras package), GNU grep (for context), and rev (because it's hilarious). BUGS: Well, like I said, this is a quick hack. It grew piece by piece on the command line. I only needed to do this once and spent hardly any time on it, so it's a bit goofy. For example, I find 'rev | cut -f1 | rev' pleasantly amusing --- it seems so clearly wrong, and yet it works to print the last argument. I think flexibility in expressiveness like this is part of the beauty of Unix shell scripting. One-off tasks can be be written quickly, built-up as a person is "thinking aloud" at the command line. That's why Unix is such a huge boost to productivity: it allows each person to think their own way instead of enforcing some "right way". On a tangent: One of the things I wish commandlinefu would show is the command line HISTORY of the person as they developed the script. I think it's that conversation between programmer and computer, as the pipeline is built piece-by-piece, that is the more valuable lesson than any canned script.

Streaming HTML5 video to icecast server using dvgrab, ffmpeg2theora and oggfwd
Streaming HTML5 compatible video (Ogg Theora video with Vorbis sound) to an Icecast server using dvgrab, ffmpeg2theora and oggfwd. In this example I'm merging stereo sound to mono (-c 1), saving the original dv for later higher quality on-demand video (tee dvstream.dv), saving the theora stream for immediate on-demand video, and publishing the stream in Xiph's stream directory (-p and the name and description). The URL of the video will be (depending on your server) http://my.icecastserver.com/stream.ogv which will play in newer Firefox, Chrome and Opera web browsers. Cortado (a Java player) can easily be used for IE. Note also that I'm using port 80, which is not the default port for Icecast, this is to avoid restrictive firewalls. Also note that ffmpeg2theora 0.25 and will heed the bitrates much better than former versions because of using libtheora 1.1 or newer.


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