function set_cookie(c_name,value,expire_days){
  var exdate = new Date();
  exdate.setDate(exdate.getDate() + expire_days);
  document.cookie = c_name + "=" + escape(value) + ((expire_days==null) ? "" : ";expires=" + exdate.toUTCString());
}

function get_cookie(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 sl_app_check_cookie(){
  sl_installed = get_cookie("sl_installed");
  if(Boolean(sl_installed) === true){
    return true;
  }
  else{
    return false;
  }
}