private function progress($string, $flags) {
		static $counter = 0;
		static $symbols = ["\\","|","/","-"];

		$this->output .= $string;
		
		if (false !== strpos($string, "\n")) {
			++$counter;
		}

		return $flags & PHP_OUTPUT_HANDLER_FINAL
			? "   \r"
			: sprintf("  %s\r", $symbols[$counter % 4]);
	}