<html>

<head>
<title></title>
<script language="javascript" type="text/javascript">
var popup;

function open_pop()
{
popup = window.open("popup.htm","pop");
}
function close_pop()
{
if(popup)
{
popup.close();
popup=null;
}
else
window.alert("Non c'è!!!");
}
</script>
</head>

<body>


Apri la pop</p>


Chiudi</p>

</body>

</html>