Copy an attribute from one element to another with jQuery
===

I have the following jQuery code which doesn't seem to be doing anything. When the link is clicked, I'm trying to get the value of its `url` attribute to be copied into the `iframe`'s `src` attribute. 

Basically this is supposed to make links open up in an iframe (the content of the iframe is replaced every time a new link is clicked) instead of acting like normal links.

So what is wrong with my code?

	$('p.tweet a').click(function(){
		var link = $(this).attr('url');
		$('iframe').attr('src',link);
	})