How to merge two avi files in ubintu linux

avimerge 
avimerge -o OUTPUT.avi -i fileavi fileavi fileavi

Install FreeNX server on ubuntu

sudo apt-get install python-software-properties && sudo add-apt-repository ppa:freenx-team
sudo apt-get update
sudo apt-get install neatx-server

Fix Alt+Print Screen not working on Ubuntu 10.10)

sysctl -w kernel.sysrq=0

nmap how-to

nmap -sP --send-ip 192.160.0.0/24

how to save rtmp stream flv

download rtmpdump :
http://rtmpdump.mplayerhq.hu/
sudo apt-get install rtmpdump 
sudo port install rtmpdump

rtmpdump -r "rtmp://stream.myonlinewebinar.com/cfx/st/lbxxx/newxxx.flv" -o 01.flv
if stuck :
rtmpdump -r "rtmp://stream.myonlinewebinar.com/cfx/st/lbxxx/newxxx.flv" -o 01.flv --stop 3600 
continue :
rtmpdump -r "rtmp://stream.myonlinewebinar.com/cfx/st/lbxxx/newxxx.flv" -o 02.flv
--start 3600 --stop 7200




reference :
http://all-streaming-media.com/record-video-stream/rtmpdump-freeware-console-RTMP-downloading-application.htm
http://stream-recorder.com/forum/do-you-use-rtmp-dump-rtmpdump-tutorials-t3926.html?s=0a7d48322bdecbb92e524308eb85f581&

how to flush the dns cache on mac osx snow leopard

dscacheutil -flushcache

How to fix - Firefox 4.0 Beta : browser.tabs.tabMinWidth doesn't work

find the firefox profile :

find . -name userChrome*

./Library/Application Support/Firefox/Profiles/mahk6fwf.#02/chrome/userChrome-example.css

cd "./Library/Application Support/Firefox/Profiles/mahk6fwf.#02/chrome/"
cp userChrome-example.css userChrome.css
vim userChrome.css

(Append to the end of the file :)

.tabbrowser-tab[fadein]:not([pinned]) {
    min-width: 18px !important;
  }

:wq

restart firefox

reference :
http://www.lawlzoids.com/proxy/?__new_url=aHR0cHM6Ly9idWd6aWxsYS5tb3ppbGxhLm9yZy9zaG93X2J1Zy5jZ2k/aWQ9NTc3NDk3

http://support.mozilla.com/bn-BD/questions/745380