Int 21 Fn 4402  - Smartdrv.sys V3.x Only - Ioctl - Get Cache Status        [c]

   AX = 4402h
   BX = file handle for device "SMARTAAR"
   CX = number of bytes to read (min 28h)
   DS:DX -> buffer for status record (see below)

Return: CF clear if successful
       AX = number of bytes actually read
   CF set on error
       AX = error code (01h,05h,06h,0Dh) (see AH=59h)

See Also: AX=4403h"SMARTDRV",INT 2F/AX=4A10h/BX=0000h

Format of SMARTDRV status record:
Offset Size    Description
 00h   BYTE    write-through flag (always 01h)
 01h   BYTE    writes should be buffered (always 00h)
 02h   BYTE    cache enabled if 01h
 03h   BYTE    driver type (01h extended memory, 02h expanded)
 04h   WORD    clock ticks between cache flushes (currently unused)
 06h   BYTE    cache contains locked tracks if nonzero
 07h   BYTE    flush cache on INT 19 reboot if nonzero
 08h   BYTE    cache full track writes if nonzero
 09h   BYTE    double buffering (for VDS) state (00h off, 01h on, 02h dynamic)
 0Ah   DWORD   original INT 13 vector
 0Eh   BYTE    minor version number
 0Fh   BYTE    major version number
 10h   WORD    unused
 12h   WORD    sectors read            \
 14h   WORD    sectors already in cache     > may be scaled rather than
 16h   WORD    sectors already in track buffer /  absolute counts
 18h   BYTE    cache hit rate in percent
 19h   BYTE    track buffer hit rate in percent
 1Ah   WORD    total tracks in cache
 1Ch   WORD    number of tracks in use
 1Eh   WORD    number of locked tracks
 20h   WORD    number of dirty tracks
 22h   WORD    current cache size in 16K pages
 24h   WORD    original (maximum) cache size in 16K pages
 26h   WORD    minimum cache size in 16K pages
 28h   DWORD   pointer to byte flag to increment for locking cache contents