Int 21/AX=4405h

SUPERSTOR - IOCTL - INSTALL CHECK

AX = 4405h
BL = drive number (00h = default, 01h = A:, etc)
(BH = 0???)
CX = 000Ch (size of SuperStor packet structure)
DS:DX -> SuperStor packet structure (see #04114)

Return:
CF clear if IOCTL successful -- check SuperStor packet for actual
status
AX = number of bytes actually transferred???
CF set on error
AX = error code (01h,05h,06h,0Dh) (see #01680 at AH=59h/BX=0000h)

Note: This function is called with CX = 0008h for command 06h by NWCACHE although the Request Packet can be larger. WINSWAP.SYS calls it with 000Ch - also for command 06h.


Format of SuperStor packet:

Offset  Size    Description     (Table 04114)
00h    WORD    (call) product signature AA55h
(ret) result code, 0000h if successful
02h    BYTE    (call) SuperStor product ID (01h)
03h    BYTE    (call) SuperStor command parameter:
06h = get compressed drive structure / drive parameters
07h = return the compressed length of a file
08h = return real drive ID for swapped drive
09h = validate the contents of the cluster
0Bh = checks whether deleted cluster is free
0Ch = reallocate previously deleted cluster
0Dh = read absolute sector from the drive
0Eh = write absolute sector to the drive
0Fh = instruct the driver to rebuild tables
10h = flush any cached Replacement Block Table (RBT) sectors
to the drive
---command 06h---
04h    DWORD   (ret) pointer to SuperStor CVF's compressed unit structure
(see #04115)
08h    DWORD   (ret) pointer to internal status structure
---command 07h---
04h    DWORD   (ret) size of file in bytes
08h    WORD    (ret) first cluster number
---command 08h---
04h    BYTE    (ret) swapped drive (0-based)
---commands 09h,0Bh,0Ch---
04h    WORD    (call) cluster
---commands 0Dh,0Eh---
04h    DWORD   (call) first logical sector to transfer
08h    WORD    (call) number of logical sectors to transfer
0Ah    DWORD   (call) pointer to buffer
---command 0Fh---
04h    WORD    (call) temporary buffer area
---command 10h---
no additional parameters

Format of SuperStor CVF compressed unit structure:

Offset  Size    Description     (Table 04115)
00h 31 BYTEs   BIOS parameter block for compressed drive (see #01663)
1Fh  5 BYTEs   reserved for future expansion of the BPB
24h 33 BYTEs   DOS 4-6 style drive parameter block for compressed drive
(see #01395)
45h  2 BYTEs   reserved for future expansion of the DPB
47h    WORD    first sector of relocation table (RBT)
49h    WORD    first sector of file allocation table
4Bh    WORD    first sector of the data area
4Dh    BYTE    sec2byteshift
4Eh  2 BYTEs   ???

Note: Reportedly these two bytes did not exist in ADDSTOR's specification, so the whole structure would have been documented differently. 50h WORD sectors per cluster 52h BYTE sector shift 53h WORD compression ratio 55h DWORD number of physical sectors in the host file 59h WORD OS version 5Bh BYTE SuperStor level 5Ch BYTE unknown??? 5Dh BYTE flags

bits 7-1:
???

bit 0:
Drive is mounted 5Eh BYTE unknown??? 5Fh DWORD pointer to CVF's underlaying host DCB this should be the physical DPB for this unit -> +00h BYTE host unit DOS unit number +01h BYTE CVF's driver host subunit number

Note: As this SuperStor compressed unit structure's structure is located within the segment the SuperStor driver has occupied, the segment value of its address can be used as an installation check, since it contains the signature "ADDSTOR" at offset 20h in the SuperStor driver. This is used by Novell DOS 7 WINSWAP.SYS to check for the presence of SuperStor.

See Also: #04114

Index:
Installation check;SuperStor

Category: Uncatagorized - Int 21h - S

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