function setCookie(c_name, value)
{
var exdate=new Date();
exdate.setDate(exdate.getDate()-1);
document.cookie=c_name+"=" +escape(value)+
((expiredays==null) ? "" : ";expires="+exdate.toGMTString());
}

function getCookie(c_name)
{
if (document.cookie.length>0)
  {
  c_start=document.cookie.indexOf(c_name + "=");
  if (c_start!=-1)
    {
    c_start=c_start + c_name.length+1;
    c_end=document.cookie.indexOf(";",c_start);
    if (c_end==-1) c_end=document.cookie.length;
    return unescape(document.cookie.substring(c_start,c_end));
    }
  }
return "";
}

function checkCookie(c_name)
{
alert('check');
username=getCookie(c_name);
if (username!=null && username!="")
  {
  alert('Welcome again '+username+'!');
  }
else
  {
 alert('no cookie');
    }
  }