Commands by eneville (0)

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Securely destroy data on given device
Intentional hash in the beginning. May run a looong time. Wipes your data for real. Was meant to be /dev/urandom - I mistyped it. :-)

GIT: list unpushed commits

find out how many days since given date
Exactly the same number of characters, exactly the same results, but with bc

Converts multiple youtube links to mp3 files
Usage: ytmp3 "YTurl" "YTurl2" "YTurl3" "YTurlN" Uses the shift command to let you extract the .mp3 from as many youtube urls as you like (or wherever else youtube-dl is supported) *Requires youtube-dl Orginal chunk of code: youtube-dl -q -t --extract-audio --audio-format mp3 URL taken from here http://www.commandlinefu.com/commands/view/9701/convert-youtube-videos-to-mp3

find and reduce 8x parallel the size of PNG images without loosing quality via optipng

Identify differences between directories (possibly on different servers)
This can be much faster than downloading one or both trees to a common servers and comparing the files there. After, only those files could be copied down for deeper comparison if needed.

Create a bunch of dummy files for testing
Sometimes I need to create a directory of files to operate on to test out some commandlinefu I am cooking up. The main thing is the range ({1..N}) expansion.

Remote copy directories and files through an SSH tunnel host
If you have lots of remote hosts sitting "behind" an ssh proxy host, then there is a special-case use of "rsynch" that allows one to easily copy directories and files across the ssh proxy host, without having to do two explicit copies: the '-e' option allows for a replacement "rsh" command. We use this option to specify an "ssh" tunnel command, with the '-A' option that causes authentication agent requests to be forwarded back to the local host. If you have ssh set up correctly, the above command can be done without any passwords being entered.

Create a backdoor on a machine to allow remote connection to bash
My netcat (nc-1.84-10.fc6) doesn't have the -e option, so I have to do it like this. Of course, instead of bash, you can use any executable, including scripts.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

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