Int 21 Fn 7303  - Windows95 - Fat32 - Get Extended Free Space On Drive     [D]

   AX = 7303h
   DS:DX -> ASCIZ string for drive ("C:\" or "\\SERVER\Share")
   ES:DI -> buffer for extended free space structure (see #1477)
   CX = length of buffer for extended free space

Return: CF clear if successful
       ES:DI buffer filled
   CF set on error
       AX = error code

Note:  this function returns a maximum of 2GB free space even on an FAT32
     partition larger than 2GB, apparently by limiting the number of
     reported clusters to no more than 64K

See Also: AX=7302h,AX=7304h,AX=7305h,AH=36h

Format of extended free space structure:
Offset Size    Description (Table 1477)
 00h   WORD    (ret) size of returned structure
 02h   WORD    (call) structure version (0000h)
       (ret) actual structure version (0000h)
 04h   DWORD   number of sectors per cluster (with adjustment for compression)
 08h   DWORD   number of bytes per sector
 0Ch   DWORD   number of available clusters
 10h   DWORD   total number of clusters on the drive
 14h   DWORD   number of physical sectors available on the drive, without
         adjustment for compression
 18h   DWORD   total number of physical sectors on the drive, without
         adjustment for compression
 1Ch   DWORD   number of available allocation units, without adjustment
         for compression
 20h   DWORD   total allocation units, without adjustment for compression
 24h  8 BYTEs  reserved