INT 2F U - DRIVER.SYS support - EXECUTE DEVICE DRIVER REQUEST AX = 0802h ES:BX -> device driver request header (see #02597) Return: request header updated as per requested operation STACK: WORD original flags from INT call (left by RETF in device driver, at least in DOS 5.0-6.22) Notes: supported by DR DOS 5.0 DOS 3.2 executes this function on any AL value from 02h through F7h; DOS 4.0+ executes this function on AL=02h and AL=04h-F7h the command codes (see #02595) and structures described below apply to all drivers which support the appropriate commands; this call is just one of a number of ways in which a device driver request may be invoked supported by Novell DOS 7 SeeAlso: AX=0800h,AX=0801h,AX=0803h,AX=1510h,INT 21/AH=52h,INT 21/AH=99h SeeAlso: INT 21/AH=9Ah (Table 02595) Values for device driver command code: 00h (0) INIT 01h (1) MEDIA CHECK (block devices) 02h (2) BUILD BPBsee BIOS Parameter Block (block devices) 03h (3) IOCTL INPUT 04h (4) INPUT 05h (5) NONDESTRUCTIVE INPUT, NO WAIT (character devices) 06h (6) INPUT STATUS (character devices) 07h (7) INPUT FLUSH (character devices) 08h (8) OUTPUT 09h (9) OUTPUT WITH VERIFY 0Ah (10) OUTPUT STATUS (character devices) 0Bh (11) OUTPUT FLUSH (character devices) 0Ch (12) IOCTL OUTPUT 0Dh (13) (DOS 3.0+) DEVICE OPEN 0Eh (14) (DOS 3.0+) DEVICE CLOSE 0Fh (15) (DOS 3.0+) REMOVABLE MEDIA (block devices) 10h (16) (DOS 3.0+) OUTPUT UNTIL BUSY (character devices) 11h (17) (European MS-DOS 4.0) STOP OUTPUT (console screen drivers only) 12h (18) (European MS-DOS 4.0) RESTART OUTPUT (console screen drivers only) 13h (19) (DOS 3.2+) GENERIC IOCTL 14h (20) (DOS 4.0, KKCFUNC) DEVICE RESTORE (character device) 15h (21) (European MS-DOS 4.0) RESET UNCERTAIN MEDIA FLAG 16h (22) (DOS 4.0) unknown??? 17h (23) (DOS 3.2+) GET LOGICAL DEVICE 18h (24) (DOS 3.2+) SET LOGICAL DEVICE 19h (25) (DOS 5.0+) CHECK GENERIC IOCTL SUPPORT 80h (128)(CD-ROM,DRFAT32) READ LONG 81h (129)(CD-ROM) reserved 82h (130)(CD-ROM,DRFAT32) READ LONG PREFETCH 83h (131)(CD-ROM,DRFAT32) SEEK 84h (132)(CD-ROM) PLAY AUDIO 85h (133)(CD-ROM) STOP AUDIO 86h (134)(CD-ROM,DRFAT32) WRITE LONG 87h (135)(CD-ROM,DRFAT32) WRITE LONG VERIFY 88h (136)(CD-ROM) RESUME AUDIO Bitfields for device request status: Bit(s) Description (Table 02596) 15 error 14-11 reserved 10 ??? set by DOS kernel on entry to some driver calls 9 busy 8 done (may be clear on return under European MS-DOS 4.0) 7-0 error code if bit 15 set (see #02598) Format of device driver request header: Offset Size Description (Table 02597) 00h BYTE length of request header 01h BYTE subunit within device driver 02h BYTE command code (see #02595) 03h WORD status (filled in by device driver) (see #02596) ---DOS--- 05h 4 BYTEs reserved (unused in DOS 2.x and 3.x) 09h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. (European MS-DOS 4.0 only) pointer to next request header in device's request queue (other versions) reserved (unused in DOS 2.x and 3.x) ---STARLITE architecture--- 05h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. pointer to next request header 09h 4 BYTEs reserved ---command code 00h--- 0Dh BYTE (ret) number of units 0Eh DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. (call) pointer to DOS device helper function (see #02599) (European MS-DOS 4.0 only) (call) pointer past end of memory available to driver (DOS 5+) (ret) address of first free byte following driver 12h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. (call) pointer to commandline arguments (ret) pointer to BPBsee BIOS Parameter Block array (block drivers) or 0000h:0000h (character drivers) 16h BYTE (DOS 3.0+) drive number for first unit of block driver (0=A) ---European MS-DOS 4.0--- 17h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. pointer to function to save registers on stack ---DOS 5+ --- 17h WORD (ret) error-message flag 0001h MS-DOS should display error msg on init failure ---command code 01h--- 0Dh BYTE media descriptor 0Eh BYTE (ret) media status 00h don't know 01h media has not changed FFh media has been changed 0Fh DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. (ret, DOS 3.0+) pointer to previous volume ID if the OPEN/CLOSE/RM bit in device header is set and disk changed Note: some drives (or controllers???) forget the change line status if another drive is accessed afterwards. The DOS IO.SYS layer takes care of this by not relying on the reported change line status when the change line is not active and a different drive is accessed, instead it reports "don't know" to the DOS kernel. ---command code 02h--- 0Dh BYTE media descriptor 0Eh DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. transfer address -> scratch sector if NON-IBM FORMAT bit in device header set -> first FATsee File Allocation Table sector otherwise 12h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. pointer to BPBsee BIOS Parameter Block (set by driver) (see #01663 at INT 21/AH=53h) ---command codes 03h,0Ch--- (see also INT 21/AX=4402h"DOS 2+",INT 21/AX=4403h"DOS") 0Dh BYTE media descriptor (block devices only) 0Eh DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. transfer address 12h WORD (call) number of bytes to read/write (ret) actual number of bytes read or written ---command codes 04h,08h,09h (except Compaq DOS 3.31, DR DOS 6)--- 0Dh BYTE media descriptor (block devices only) 0Eh DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. transfer address 12h WORD byte count (character devices) or sector count (block devices) 14h WORD starting sector number (block devices only) 16h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. (DOS 3.0+) pointer to volume ID if error 0Fh returned 1Ah DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. (DOS 4.0+) 32-bit starting sector number (block devices with device attribute word bit 1 set only) if starting sector number above is FFFFh (see INT 21/AH=52h) ---command codes 04h,08h,09h (Compaq DOS 3.31, DR DOS 6)--- 0Dh BYTE media descriptor (block devices only) 0Eh DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. transfer address 12h WORD byte count (character devices) or sector count (block devices) 14h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. 32-bit starting sector number (block devices only) Note: to reliably determine which variant of the request block for functions 04h,08h,09h has been passed to the driver, check the length field as well as the word at offset 14h. If the length is 1Eh and 14h=FFFFh, use the DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. at 1Ah as the starting sector number; if the length is 18h, use the DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. at 14h; otherwise, use the WORD at 14h. ---command code 05h--- 0Dh BYTE byte read from device if BUSY bit clear on return ---command codes 06h,07h,0Ah,0Bh,0Dh,0Eh,0Fh--- no further fields ---command code 10h--- 0Dh BYTE unused 0Eh DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. transfer address 12h WORD (call) number of bytes to write (ret) actual number of bytes written ---command codes 11h,12h--- 0Dh BYTE reserved ---command code 14h--- no further fields Note: This is at least true for KKCFUNC.SYS' "device restore". KKCFUNC.SYS checks that INT 2Fh in the IVTsee Interrupt Vector Table still points to KKCFUNC's own INT 2Fh entry point. In this case it restores the original INT 2Fh vector, as recorded at device init, into the IVTsee Interrupt Vector Table. SeeAlso: INT 2F/AH=4Dh ---command code 15h--- no further fields ---command codes 13h,19h--- 0Dh BYTE category code 00h-7Fh reserved for Microsoft 00h unknown 01h COMn: (serial) (DOS 3.3+) 02h reserved for terminal control 03h CON (DOS 3.3+) 04h reserved for keyboard control 05h LPTn: 07h mouse (European MS-DOS 4.0) 08h disk 48h FAT32 disk control (MS-DOS 7.10+) 80h-FFh reserved for OEM(Original Equipment Manufacturer) a company which purchases components that are resold as part of its own products under the company's own brand name, e.g. a Gateway 2000-branded monitor may actually be a Mag or NEC monitor./user-defined 9Eh (STARLITE) Media Access Control driver EDh (DR PalmDOS) login security SeeAlso: #01558 0Eh BYTE function code 00h (STARLITE) MAC Bind request 0Fh WORD copy of DS at time of IOCTL call (apparently unused in DOS 3.3) SI contents (European MS-DOS 4.0) 11h WORD offset of device driver header (see #01646) DI contents (European MS-DOS 4.0) 13h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. pointer to parameter block from INT 21/AX=440Ch or AX=440Dh ---command codes 80h,82h--- 0Dh BYTE addressing mode 00h HSG (default) 01h Phillips/Sony Red Book 0Eh DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. transfer address (ignored for command 82h) 12h WORD number of sectors to read (if 0 for command 82h, request is an advisory seek) 14h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. starting sector number logical sector number in HSG mode frame/second/minute/unused in Red Book mode (HSG sector = minute * 4500 + second * 75 + frame - 150) 18h BYTE data read mode 00h cooked (2048 bytes per frame) 01h raw (2352 bytes per frame, including EDC/ECC) 19h BYTE interleave size (number of sectors stored consecutively) 1Ah BYTE interleave skip factor (number of sectors between consecutive portions) ---command code 83h--- 0Dh BYTE addressing mode 00h HSG (default) 01h Phillips/Sony Red Book 0Eh DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. transfer address (ignored) 12h WORD number of sectors to read (ignored) 14h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. starting sector number (see also above) ---command code 84h--- 0Dh BYTE addressing mode 00h HSG (default) 01h Phillips/Sony Red Book 0Eh DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. starting sector number (see also above) 12h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. number of sectors to play ---command codes 85h,88h--- no further fields ---command codes 86h,87h--- 0Dh BYTE addressing mode 00h HSG (default) 01h Phillips/Sony Red Book 0Eh DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. transfer address (ignored in write mode 0) 12h WORD number of sectors to write 14h DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. starting sector number (also see above) 18h BYTE write mode 00h mode 0 (write all zeros) 01h mode 1 (default) (2048 bytes per sector) 02h mode 2 form 1 (2048 bytes per sector) 03h mode 2 form 2 (2336 bytes per sector) 19h BYTE interleave size (number of sectors stored consecutively) 1Ah BYTE interleave skip factor (number of sectors between consecutive portions) (Table 02598) Values for device driver error code: 00h write-protect violation 01h unknown unit 02h drive not ready 03h unknown command 04h CRC error 05h bad drive request structure length 06h seek error 07h unknown media 08h sector not found 09h printer out of paper 0Ah write fault 0Bh read fault 0Ch general failure 0Dh reserved 0Eh (CD-ROM) media unavailable 0Fh invalid disk change (Table 02599) Call European MS-DOS 4.0 device helper function with: DL = function 00h "SchedClock" called on each timer tick AL = tick interval in milliseconds 01h "DevDone" device I/O complete ES:BX -> request header Note: must update status word first; may be called from an interrupt handler 02h "PullRequest" pull next request from queue DS:SI -> DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. pointer to start of device's request queue Return: ZF clear if pending request ES:BX -> request header ZF set if no more requests 03h "PullParticular" remove specific request from queue DS:SI -> DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. pointer to start of device's request queue ES:BX -> request header Return: ZF set if request header not found 04h "PushRequest" push the request onto the queue DS:SI -> DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. pointer to start of device's request queue ES:BX -> request header interrupts disabled 05h "ConsInputFilter" keyboard input check AX = character (high byte 00h if PCIBM PC ASCII character) Return: ZF set if character should be discarded ZF clear if character should be handled normally Note: called by keyboard interrupt handler so DOS can scan for special input characters 06h "SortRequest" push request in sorted order by starting sector DS:SI -> DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. pointer to start of device's request queue ES:BX -> request header interrupts disabled 07h "SigEvent" send signal on keyboard event AH = event identifier Return: AL,FLAGS destroyed 09h "ProcBlock" block on event AX:BX = event identifier (typically a pointer) CX = timeout in ms or 0000h for never DH = interruptable flag (nonzero if pause may be interrupted) interrupts disabled Return: after corresponding ProcRun call CF clear if event wakeup, set if unusual wakeup ZF set if timeout wakeup, clear if interrupted AL = wakeup code, nonzero if unusual wakeup interrupts enabled BX,CX,DX destroyed Note: block process and schedules another to run 0Ah "ProcRun" unblock process AX:BX = event identifier (typically a pointer) Return: AX = number of processes awakened ZF set if no processes awakened BX,CX,DX destroyed 0Bh "QueueInit" initialize/clear character queue DS:BX -> character queue structure (see #02600) Note: the queue size field must be set before calling 0Dh "QueueWrite" put a character in the queue DS:BX -> character queue (see #02600) AL = character to append to end of queue Return: ZF set if queue is full ZF clear if character stored 0Eh "QueueRead" get a character from the queue DS:BX -> character queue (see #02600) Return: ZF set if queue is empty ZF clear if characters in queue AL = first character in queue 10h "GetDOSVar" return pointer to DOS variable AL = index of variable 03h current process ID BX = index into variable if AL specifies an array CX = expected length of variable Return: CF clear if successful DX:AX -> variable CF set on error AX,DX destroyed BX,CX destroyed Note: the variables may not be modified 14h "Yield" yield CPU(Central Processing Unit) The microprocessor which executes programs on your computer. if higher-priority task ready to run Return: FLAGS destroyed 1Bh "CritEnter" begin system critical section DS:BX -> semaphore (6 BYTEs, initialized to zero) Return: AX,BX,CX,DX destroyed 1Ch "CritLeave" end system critical section DS:BX -> semaphore (6 BYTEs, initialized to zero) Return: AX,BX,CX,DX destroyed Note: must be called in the context of the process which called CritEnter on the semaphore Note: the DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. pointing at the request queue must be allocated by the driver and initialized to 0000h:0000h. It always points at the next request to be executed Format of European MS-DOS 4.0 character queue: Offset Size Description (Table 02600) 00h WORD size of queue in bytes 02h WORD index of next character out 04h WORD count of characters in the queue 06h N BYTEs queue buffer