INT 21 - Stacker - GET STACVOL FILE SECTORS
AX = 4404h
BL = drive number (0 is current drive)
CX = byte count (i.e., 200h = 1 sector)
DS:DX -> buffer (see below)
Return: Data Buffer contains the number of sectors requested from the
STACVOL physical file for the drive specified.

Format of stacker buffer:
Offset  Size    Description
00h    WORD    01CDh
02h    WORD    sector count
04h    DWORD   number of starting sector
08h    DWORD   far pointer to Data Buffer


214404 - Stacker - GET STACVOL FILE SECTORS