Webrtc
build & install
http://www.webrtc.org/reference/getting-started
cd /tmp
mkdir webrtc
svn co http://src.chromium.org/svn/trunk/tools/depot_tools
./depot_tools/gclient config http://webrtc.googlecode.com/svn/trunk
./depot_tools/gclient sync --force
cd trunk
./build/install-build-deps.sh
make peerconnection_server
make peerconnection_client
./out/Debug/peerconnection_server
./out/Debug/peerconnection_client
testing
http://www.webrtc.org/running-the-demos
sample code
https://github.com/ging/webrtc_demo
javascript
If the variable hasn't been declared, you wont be able to test for undefined using a function because you will get an error.
if (foo) {}
function (bar) {}(foo)
Both will generate an error if foo has not been declared.
If you want to test if a variable has been declared you can use
typeof foo != "undefined"
if you want to test if foo has been declared and it has a value you can use
if (typeof foo != "undefined" && foo) {
//code here
}