function newCookie(name,value,days) {
 	var days = 30;   // the number at the left reflects the number of days for the cookie to last
    	
	if (days) {
   		var date = new Date();
   		date.setTime(date.getTime()+(days*24*60*60*1000));
   		var expires = "; expires="+date.toGMTString(); }
   		else var expires = "";
   		document.cookie = name+"="+value+expires+"; path=/"; 
}

function readCookie(name) {
	var nameSG = name + "=";
   	var nuller = '';
  	if (document.cookie.indexOf(nameSG) == -1)
    	return nuller;

   	var ca = document.cookie.split(';');
  	for(var i=0; i<ca.length; i++) {
	    var c = ca[i];
		    while (c.charAt(0)==' ') c = c.substring(1,c.length);
  				if (c.indexOf(nameSG) == 0) return c.substring(nameSG.length,c.length); 
  	}
    return null; 
}

function eraseCookie(name) {
  newCookie(name,"",1); 
}