// This a genric cookie handling lib 
// three public functions
// String GetCookie( name ) - returns the value of a given cookie
// SetCookie( name , value ) - store a cookie
// DeleteCookie( name ) - Guess...

// Expire date for cookies defaults to 30 days.
var expDays = 30;
var exp = new Date();
exp.setTime(exp.getTime() + (expDays*24*60*60*1000));

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 expires = exp;
 document.cookie = name + "=" + escape (value) +
   ((expires == null) ? "" : ("; expires=" + expires.toGMTString())) ;
}

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