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url redirect tracer with curl
tracing redirects for a given url shortener

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.

Compute the numeric sum of a file
In the file data.txt there is a single column of numbers. Sed adds a "+" between lines and xargs prepares the output for bc. The "echo 0" is to avoid to have a "+" at the beginning of the line.

List only executables installed by a debian package
Safe for whitespaces in names.

check open ports without netstat or lsof

Reducing image size
Adding the exclamation mark to the image geometry ignores the original aspect ratio. More info about image geometry: http://www.imagemagick.org/script/command-line-processing.php#geometry

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"

Alias to edit and source your .bashrc file
Place the line above in your ~/.bahsrc file. Now every time you issue the 'vb' command, you invoke the vim editor to edit it, then source it so the changes take effect immediately. Notes: * This mechanism is not working well if your .bashrc contains commands that should not be sourced more than once. * This trick also work for your csh or tclsh users: place the following line in your ~/.cshrc file: alias vc 'vim ~/.cshrc; source ~/.cshrc Thank you adzap for pointing out the missing quote

generate random password
-B flag = don't include characters that can be confused for other characters (this helps when you give someone their password for the first time so they don't cause a lockout with, for example, denyhosts or fail2ban) -s flag = make a "secure", or hard-to-crack password -y flag = include special characters (not used in the example because so many people hate it -- however I recommend it) "1 10" = output 1 password, make it 10 characters in length For even more secure passwords please use the -y flag to include special characters like so: $ pwgen -Bsy 10 1 output>> }&^Y?.>7Wu

Alternative way to generate an XKCD #936 style 4 word password usig sed
This is what I came up to generate XKCD #936 style four-word password. Since first letter of every word is capitalized it looks a bit more readable to my eyes. Also strips single quotes. And yes - regex is a bit of a kludge, but that's the bes i could think of.


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