protected function compressioncheck($comptype)
    {
        if ($comptype === Archive::COMPRESS_GZIP && !function_exists('gzopen')) {
            throw new ArchiveIllegalCompressionException('No gzip support available');
        }

        if ($comptype === Archive::COMPRESS_BZIP && !function_exists('bzopen')) {
            throw new ArchiveIllegalCompressionException('No bzip2 support available');
        }
    }