DSRawRead

mov    ax, 4404h             ; IOCTL command
mov    bl, Drive             ; drive number (one-based)
mov    cx, size DataPacket   ; size of data packet
mov    dx, seg DataPacket    ; address of data packet
mov    ds, dx
mov    dx, offset DataPacket 
int    21h

jc     error
cmp    DataPacket.dspResult, ; 'OK' ; test for success
jne    failure               ; call failed

Reads raw data from a compressed volume file (CVF) into a buffer.

Returns with the carry flag clear and the dspResult of the DSHDR structure set to 'OK' if the function succeeds; otherwise, the carry flag is set and AX contains one of these error values:

Value	Meaning
0001h	ERROR_INVALID_FUNCTION
0005h	ERROR_ACCESS_DENIED
0006h	ERROR_INVALID_HANDLE
000Dh	ERROR_INVALID_DATA

Drive

One-based driver number for a DriveSpace driver (1 = A, 2 = B, and so on). If there is more than one DriveSpace drive, any one of the corresponding drive numbers can be given.

DataPacket

Data packet consisting of a DSHDR structure, a DSRAWIO structure, and an array of RawClusterInfo structures. The dspCommand field of the DSHDR structure must be set to the letter 'R'. The buffer pointed to by the rci_pdata field of the RawClusterInfo structure receives the raw data.

See also DSHDR, DSRAWIO, RawClusterInfo