INT 2F - DBLSPACE.BIN - "GetDriveSpace" - GET SPACE AVAIL ON COMPRESSED DRIVE
	AX = 4A11h
	BX = 0007h
	DL = compressed drive number (0=A:)
Return: AX = status (0000h,0102h) (see also #02804)
	    0000h successful
		DS:SI -> free space record (see #02807)
Program: DBLSPACE.BIN is the resident driver for DoubleSpace, the
	  disk-compression software bundled with MS-DOS 6.0
SeeAlso: AX=4A11h/BX=0000h,AX=4A11h/BX=0008h


Format of DBLSPACE free space record:
Offset	Size	Description	(Table 02807)
 00h	DWORDDoubleword; four bytes.	 Commonly used to hold a 32-bit segment:offset or selector:offset address.	total number of sectors in drive's sector heap
 04h	DWORDDoubleword; four bytes.	 Commonly used to hold a 32-bit segment:offset or selector:offset address.	number of free sectors in drive's sector heap