Feedburner counter #2

// Feedburner counter

function nlt_getFeedCounter($feedid='medicsovet'){
    $output = get_transient('rss_counter');
    if (!isset($output['lastcheck'])) $output['lastcheck'] = 0;
    if (!isset($output['count'])) $output['count'] = 0;
    if (!isset($output['feedid'])) $output['feedid'] = '';
    if ($output['lastcheck'] < (mktime() - 3600) || $output['feedid'] != $feedid) {
        $url = 'http://feedburner.google.com/api/awareness/1.0/GetFeedData?uri=' . $feedid;
        $headers = get_headers($url);
        if (strpos($headers[0], '200')) {
            $xml = file_get_contents($url);
            preg_match('/circulation="(\d+)"/', $xml, $match);
            if ($match[1] != 0) {
                $output['count'] = $match[1];
                $output['lastcheck'] = mktime();
                $output['feedid'] = $feedid;
                set_transient('rss_counter', $output, 60*10 );
            }
        }
    }
    echo $output['count'];
}