Format of DR DOS 5.0-6.0 internal variable table |
| Offset | Size | Description |
|---|---|---|
|
00h |
WORD |
??? |
|
02h |
WORD |
segment of ??? |
|
04h |
WORD |
offset within DOS data segment of history control structure for COMMAND.COM history buffer (see #01586) |
|
06h |
WORD |
offset within DOS data segment of history control structure for application history buffer (see #01586) |
|
08h |
BYTE |
initial history state flags (see #01583) |
|
09h |
2 BYTEs |
??? |
|
0Bh |
WORD |
KB of extended memory at startup |
|
0Dh |
BYTE |
number of far jump entry points |
|
0Eh |
WORD |
segment containing far jumps to DR DOS entry points (see #01587) |
|
10h |
WORD |
(only if kernel loaded in HMA) offset in HMA of first free HMA memory block (see #01588) or 0000h if none; segment is FFFFh |
|
12h |
WORD |
pointer to segment of environment variables set in CONFIG, or 0000h if already used |
|
---DR DOS 6.0--- |
||
|
14h |
WORD |
(only if kernel loaded in HMA) offset in HMA of first used HMA memory block (see #01588) or 0000h if none; segment is FFFFh |
|
16h |
8 BYTEs |
??? |
|
1Eh |
WORD |
offset in DOS data segment of full COUNTRY.SYS filename |
|
20h |
8 BYTEs |
??? |
|
28h |
WORD |
offset in DOS data segment of SHARE hook table |
|
2Ah |
2 BYTEs |
??? |
|
2Ch |
WORD |
offset in DOS data segment of far pointer to INT 2F/AX=1000h handler |
|
Note: |
The segment used for the DR DOS 6.0 CONFIG environment
variables (excluding COMSPEC, VER and OS) is only useful for programs/drivers
called from CONFIG.SYS. The word is set to zero later when the area is copied to
the COMMAND.COM environment space. This allows CONFIG.SYS to pass information to
AUTOEXEC.BAT. |