function writeUrl()
{
	url = "/envoyerAmi.do?";
	if(location.href.indexOf("?f=") != -1){
		params = location.href.substring(location.href.lastIndexOf("?f=")+3);
	}else{
		params = location.href.substring(location.href.lastIndexOf("&f=")+3);
	}
	if (params.indexOf("&")!=-1) {
		params = params.substring(0,params.indexOf("&"));
	}
	url = url+"f="+params+"&url=";
	url = url+ escape(location);
	return url;	
}