Table of Contents
Note: This API call is for DOS personality only. Use Family API for portability.
Int 21H, AH=33H, AL=05H
Version
4.0 and higher
Brief
GET BOOT DRIVE
Family API
Input
AX = 3305h
Return
DL = boot drive (1=A:,…)
Macro
Notes
This function does not use any of the DOS-internal stacks and may
thus be called at any time. It is directly dispatched from
the INT 21h entry point with interrupts disabled.
NEC 9800-series PCs always call the boot drive A: and assign the other
drive letters sequentially to the other drives in the system
this call is supported by OS/2 Warp 3.0, but not earlier versions of
OS/2; it is also supported by Novell DOS 7
See also
Note
Text based on Ralf Brown Interrupt List Release 61
| DOS API | |
|---|---|
| Process manager | INT 20H, INT 21H: 00H, 25H, 26H, 31H, 34H, 35H, 4CH, INT 22H, INT 27H, INT 28H |
| File manager | INT 25H, INT 26H, INT 21H: 0DH, 0EH, 0FH, 10H, 11H, 12H, 13H, 14H, 15H, 16H, 17H, 19H, 1AH, 1BH, 1CH, 21H, 22H, 23H, 24H, 27H, 28H, 29H, 2EH, 2FH, 32H, 3305H, 36H |
| Character Device I/O | INT 29H, INT 21H: 01H, 02H, 03H, 04H, 05H, 06H, 07H, 08H, 09H, 0AH, 0BH, 0AH, 0CH |
| Signals | INT 23H, INT 24H, INT 21H: 3300H, 3301H, 3302H |
| Memory manager | |
| Date and Time | INT 21H: 2AH, 2BH, 2CH, 2DH |
| Misc | INT 21H: 30H, 3306H, 3700H, 3701H, 3702H, 3703H |
| NLS | INT 21H: 3303H, 3304H |
