OSの判別をして専用ページに移動

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<META http-equiv="Content-Type" content="text/html; charset=Shift_JIS">
<META http-equiv="Content-Style-Type" content="text/css">
<title>OSの判別</title>
<style type="text/css">
<!--
body { text-align: center;}
-->
</style>
</head>
<body bgcolor="#FFFFFF">
OSの判別をして専用ページに移動
<p>
<script language="JavaScript">
<!--
var os_info = "";
if (navigator.userAgent.indexOf("Win",0) != -1) {//userAgentにWinが含まれているか？
os_info = "windows";
}
else{
if( navigator.userAgent.indexOf("Mac",0) != -1){//userAgentにMacが含まれているか？
os_info = "macos";
}
else{//それ以外のOS
os_info = "otheros";
}
}
if (os_info == "windows") {//windows系OSなら
location.href = "win.html";
}
else{
if (os_info == "macos") {//mac系OSなら
location.href = "mac.html";
}
else{//それ以外のOSなら
location.href = "other.html";
}
}
//-->
</script>
</body>
</html>