function open_w(url, w, h, s)
{
  var parametry = null;
  var nove_okno = null;
  parametry = "width=" + w + "; height=" + h + "; resizable=0; scrollbars=" + s + "; toolbar=0;"
  nove_okno = window.open(url, null, parametry);
  nove_okno.returnValue = null;
  nove_okno.focus();
}