function winOpen(theURL,winName,features) 
{ 
winName = window.open(theURL,winName,features); 
if(winName == null || winName.closed){window.open(theURL,winName,features);} 
else{winName.location.href = theURL;} 
if (!winName.closed) 
winName.focus(); 
}

function roll(name, src) 
{
  document[name].src = src;
}