Category: <b>DOS extenders</b>
<br>Flags: Undocumented function, available only in protected mode<p>
<pre><b>INT 21 - Rational Systems DOS/4GW - ???</b>

	AH = FFh
	DH = 0Ah
	AL = ???
	BX = ???
	CX = ???
Return: ES = ??? or 0000h
</pre>