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Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

send echo to socket network
this command will send a message to the socket 25 on host 192.168.1.2 in tcp. works on udp and icmp understand only IP address, not hostname. on the other side (192.168.1.2), you can listen to this socket and test if you receive the message. easy to diagnose a firewall problem or not.

How to run a command on a list of remote servers read from a file
dsh - Distributed shell, or dancer?s shell ;-) you can put your servers into /etc/dsh/machines.list than you don't have to serperate them by commata or group them in different files and only run commands for this groups dsh -M -c -a -- "apt-get update"

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" }

Get the Volume labels all bitlocker volumes had before being encrypted
Get information of volume labels of bitlocker volumes, even if they are encrypted and locked (no access to filesystem, no password provided). Note that the volume labels can have spaces, but only if you name then before encryption. Renaming a bitlocker partition after being encrypted does not have the same effect as doing it before.

Perl Command Line Interpreter
Read, Evaluate, Print, Loop - REPL

Stream YouTube URL directly to mplayer.
This is the result of a several week venture without X. I found myself totally happy without X (and by extension without flash) and was able to do just about anything but watch YouTube videos... so this a the solution I came up with for that. I am sure this can be done better but this does indeed work... and tends to work far better than YouTube's ghetto proprietary flash player ;-) Replace $i with any YouTube ID you want and this will scrape the site for the _real_ URL to the full quality .FLV file on Youtube's server and will then will hand that over to mplayer (or vlc or whatever you want) to be streamed. In some browsers you can replace $i with just a % or put this in a shell script so all YouTube IDs can be handed directly off to your media player of choice for true streaming without the need for Flash or a downloader like clive. (I do however fully recommend clive if you wish to archive videos instead of streaming them) If any interest is shown I would be more than happy to provide similar commands for other sites. Most streaming flash players use similar logic to YouTube. Edit: 05/03/2011 - Updated line to work with current YouTube. It could be a lot prettier but I will probably follow up with another update when I figure out how to get rid of that pesky Grep. Sed should take that syntax... but it doesn't. Original (no longer working) command: mplayer -fs $(echo "http://youtube.com/get_video.php?$(curl -s $youtube_url | sed -n "/watch_fullscreen/s;.*\(video_id.\+\)&title.*;\1;p")")

list block devices
Shows all block devices in a tree with descruptions of what they are.

AWS Route53 hosted zone export
Frustrated with the manual domain migration process AWS has, I unsuccessfully tried to install cli53, route53-transfer. I instead wrote this oneliner to ease the export (which is not supported via the AWS console ATM). The output can be easily pasted into the "Import Hosted Zone" dialog in Route53. SOA/NS records are excluded since they cannot be automatically imported.


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