<?
function authenticate() {
	Header("WWW-authenticate: basic realm=\"PHP Auth\"");
	Header("HTTP/1.0 401 Unauthorized");?>
	In order to proceed you will need a valid username/password.
	<?
	exit;
}

if (!isset($PHP_AUTH_USER)) {
	authenticate();
} else {
	$id = strtolower($PHP_AUTH_USER);
	$pass = $PHP_AUTH_PW;
	# put authentication code here
}
?>