can anyone tell me why it wont authenticate the username and password please?


auth.php:
=========

Code:
<?php 

	// File Name: auth03.php

	// Check to see if $PHP_AUTH_USER already contains info

	if (!isset($PHP_AUTH_USER)) {

		// If empty, send header causing dialog box to appear

		header('WWW-Authenticate: Basic realm="My Private Stuff"');
		header('HTTP/1.0 401 Unauthorized');
		exit;

	} else if (isset($PHP_AUTH_USER)) {

		// If non-empty, open file containing valid user info

		$filename = "/path/to/file.txt";
		$fp = fopen($filename, "r");
		$file_contents = fread($fp, filesize($filename));
		fclose($fp);

		// Place each line in user info file into an array

		$line = explode("\n", $file_contents);

		// For as long as $i is <= the size of the $line array, 
		// explode each array element into a username and password pair


		$i = 0;

		while($i <= sizeof($line)) {			
			$data_pair = explode(":", $line[$i]);

			if (($data_pair[0] == "$PHP_AUTH_USER") && ($data_pair[1] ==
"$PHP_AUTH_PW")) {
				$auth = 1;
				break;
			} else {
				$auth = 0;
			}
			$i++;
		}

		if ($auth == "1") {

			echo "<P>You're authorized!</p>";	
			exit;

		} else {	

			header('WWW-Authenticate: Basic realm="My Private Stuff"');
			header('HTTP/1.0 401 Unauthorized');
			echo 'Authorization Required.';
			exit;

	} 
}

?>

file.txt:
=========

Code:
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