Need help with http authenication

[Randomi]

When I do the echo, it prints the variable, not what it's stored in it. I tried $PHP_AUTH_USER and PHP_AUTH_PW but it just returns blank when I print it.

<?php
session_start();
include('functions.php');
if ($_SESSION['auth'] == 'true') {
PrintTop();
ListInfos();
PrintEnd();
exit;
} else {
if ((!isset( $_SERVER['PHP_AUTH_USER'] )) && (!isset($_SERVER['PHP_AUTH_PW'])) && ( $_SERVER['PHP_AUTH_USER'] != 'CreativeClan' ) && ( $_SERVER['PHP_AUTH_PW'] != 'Vanilla' ) ) {
    header( 'WWW-Authenticate: Basic realm="Private"' );
    header( 'HTTP/1.0 401 Unauthorized' );
    echo 'Authorization Required.';
    echo '$_SERVER["PHP_AUTH_USER"] is the username, and $_SERVER["PHP_AUTH_PW"] is the password.';
    exit;
} else {
	$_SESSION['auth'] = 'true';
	PrintTop();
	ListInfos();
	PrintEnd();
	exit;
}
}
?>

[weekender]

to put an array in an output like that, you have to enclose it in {}

echo '{$_SERVER["PHP_AUTH_USER"]}...'

[Weedpacket]

Variables aren't interpolated if the string they're in is delimited by 'single quotes'. Use "double quotes" for your string or - faster and arguably easier to work with - use string concatenation.