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

function getCookie (name) {
 var arg = name + "=";
 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;
}

function setCookie (name, value) {
 var argv = setCookie.arguments;
 var argc = setCookie.arguments.length;

 var date_never = new Date('Jan 1, 2016');
 var expires = (argc > 2) ? argv[2] : date_never;
 var path = (argc > 3) ? argv[3] : '/';
 var domain = (argc > 4) ? argv[4] : null;
 var secure = (argc > 5) ? argv[5] : false;
 document.cookie = name + "=" + escape (value) +
   ((expires == null) ? "" : ("; expires=" + expires.toGMTString())) +
   ((path == null) ? "" : ("; path=" + path)) +
   ((domain == null) ? "" : ("; domain=" + domain)) +
   ((secure == true) ? "; secure" : "");
}

function deleteCookie (name) {
 var exp = new Date();
 exp.setTime (exp.getTime() - 1);
 var cval = getCookie (name);
 document.cookie = name + "=" + cval + "; expires=" + exp.toGMTString();
}