Table of Contents
Note: This API call is for DOS and Win16 personality only. Use Family API for portability.
Int 21H, AH=0EH
Version
1 and higher
Brief
SELECT DEFAULT DRIVE
Family API
Input
- AH = 0Eh
- DL = new default drive (00h = A:, 01h = B:, etc)
Return
- AL = number of potentially valid drive letters
Notes
under Novell NetWare, the return value is always 32, the number of drives that NetWare supports
under DOS 3.0+, the return value is the greatest of 5, the value of LASTDRIVE= in CONFIG.SYS, and the number of drives actually present on a DOS 1.x/2.x single-floppy system, AL returns 2 since the floppy may be accessed as either A: or B: otherwise, the return value is the highest drive actually present
DOS 1.x supports a maximum of 16 drives, 2.x a maximum of 63 drives, and 3+ a maximum of 26 drives
under Novell DOS 7, this function returns the correct LASTDRIVE value even when the undocumented LASTDRIVE=27..32 directive was used in CONFIG.SYS
“parse FCB” (see AH=29H) can be used to determine whether a drive letter is valid
See also
Note
Text based on Ralf Brown Interrupt List Release 61
| osFree Macro Library | |
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