public function flush(?string $chunk, bool $flushEmpty = false): void
	{
		if($this->isCGI)
		{
			if(!empty($chunk))
			{
				echo $chunk;

				flush();
			}
		}
		else
		{
			if(!empty($chunk) || $flushEmpty === true)
			{
				printf("%x\r\n%s\r\n", strlen($chunk), $chunk);

				flush();
			}
		}
	}