function getCookieVal(offset){
	var endstr=document.cookie.indexOf (";", offset);
	if (endstr==-1) endstr=document.cookie.length;
	return unescape(document.cookie.substring(offset, endstr)); 
}

function LireCookie(nom){
	var arg=nom+"=";
	var alen=arg.length;
	var clen=document.cookie.length;
	var i=0;
	while (i<clen) {
		var j=i+alen;
		if (document.cookie.substring(i, j)==arg) return getCookieVal(j);
		i=document.cookie.indexOf(" ",i)+1;
		if (i==0) break;
	}
	return null; 
}