gzencode and stream http archive

function gzip_and_stream_archive($archive_file_path)
{
        if (file_exists($archive_file_path)) {
                if (function_exists('gzencode')) {
                        $archive_size = filesize($archive_file_path);
                        $fp = fopen($archive_file_path, 'r');
                        if ($fp) {
                                // send gzipped archive
                                header("Content-Encoding: gzip");
                                header("Content-Length: " . $archive_size);
                                header("Content-Disposition: attachment; filename=backup.tar.gz");
                                print(gzencode(fread($fp, $archive_size)));
                                fclose($fp);
                                unlink($archive_file_path);
                                return true;
                        }
                } else {
                        // send unencoded archive
                        header("Content-Type: application/x-gzip");
                        header("Content-Length: " . filesize($archive_file_path));
                        header("