Category: <b>other operating systems</b>
<br>Flags: Undocumented function<p>
<pre><b>INT 21 - OS/2 v2.1+ Virtual DOS Machine - GET SIZE OF PTDA JFT</b>

	AH = 64h
	DX = 0004h (function number)
	CX = 636Ch (magic value, "cl")
	BX = 0000h (indicates special request)
Return: AX = number of entries in OS/2 JFT for VDM
Notes:	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
	in an OS/2 VDM, the DOS Job File Table in the PSP contains an index
	  into the OS/2 JFT in the Per-Task Data Area rather than an SFT index
	  because the OS/2 SFT can contain more than 255 entries
</pre>