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 #1134)
Return: CF clear if successful
AX = number of bytes actually read
CF set on error
AX = error code (01h,05h,06h,0Dh) (see #1366 at AH=59h/BX=0000h)
Note: NCache2 (from the Norton Utilities v8.0) attempts to support this
interface, but does not do so correctly, often hanging the system;
one should use the SmartDrive v4.x or NCache private interfaces
(see INT 2F/AX=4A10h/BX=0000h,INT 2F/AX=FE00h/DI=4E55h)
See Also: AX=4403h"SMARTDRV",INT 2F/AX=4A10h/BX=0000h
Format of SMARTDRV status record:
Offset Size Description (Table 1134)
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