Category: <b>other operating systems</b>
<br>Flags: Undocumented function<p>
<pre><b>INT 21 - OS/2 v2.0+ Virtual DOS Machine - ENABLE AUTOMATIC TITLE SWITCH</b>

	AH = 64h
	DX = 0000h (function number)
	CX = 636Ch (magic value, "cl")
	BX = 0000h (indicates special request)
Note:	if CX is not 636Ch on entry, INT 21/AH=6Ch is invoked, because a bug
	  in OS/2 1.x FAPI erroneously called AH=64h instead of AH=6Ch
SeeAlso: AH=64h/DX=0001h,INT 21/AH=4Bh
</pre>