[Windows 95 only.]
Returns a copy of the extended DPB (FAT32) for any valid drive.
Buffer dw ?
DriveDPB DPB <>
BufferSize equ sizeof DPB + sizeof WORD
...
mov dx, seg Buffer
mov es, dx
mov di, offset Buffer ;See below
mov dl, DriveNum ;See below
mov cx, BufferSize ;See below
mov ax, 7302h ;Get_ExtDPB
int 21h
jc error_handler ;carry set means error
The size value returned by this function represents the size of the DPB only. It does not include the two bytes of the size field itself.
This call will not work when the VDEF file system is mounted on the drive (for example during formatting).
Clears the carry flag, and returns a copy of the DPB to ES:DI. The copy is a WORD equal to the size (in bytes) of the extended DPB, followed by the extended DPB itself (see EA_DEVICEPARAMETERS (FAT32)).
When calling this function with DeviceIoControl, it is recommended to set the dwloControlCode parameter to VWIN32_DIOC_DOS_IOCTL (defined as 6 in VWIN32.H). For more information on this, see Using VWIN32 to Carry Out MS-DOS Functions.