Use of this subfunction should be avoided. Application programs should not distinguish between files on local and remote devices.Checks whether the specified block device is local (attached to the computer running the program) or remote (redirected to a network server).
Call with:
AH = 44H
AL = 09H
BL = drive number (0 = default, 1 = A, 2 = B, etc.)
Returns:
If function successful
Carry flag = clear
DX = device attribute word
bit 12 = 0 if drive is local
1 if drive is remote
If function unsuccessful
Carry flag = set
AX = error code
Note:
Use of this subfunction should be avoided. Application programs should not distinguish between files on local and remote devices.
Example:
Check whether drive D is mounted on the machine running the program or is a network drive.
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mov ax,4409h ; function & subfunction
mov bl,4 ; drive 4 = D
int 21h ; transfer to MS-DOS
jc error ; jump if function failed
and dx,1000h ; test local/remote bit
jnz remote ; jump if network drive
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