INT 21 U - DOS 4.0 internal - ???
AH = 6Bh
AL = subfunction
00h ???
DS:SI -> Current Directory Structure???
CL = drive (1=A:)
01h ???
DS:SI -> ???
CL = file handle???
02h ???
DS:SI -> Current Directory Structure???
DI = ???
CX = drive (1=A:)
Return: CF set on error
AX = error code (see INT 21/AH=59h)
CF clear if successful
Note:   passed through to INT 2F/AX=112Fh with AX on top of stack
SeeAlso: INT 2F/AX=112Fh

See also: 216B

216B - DOS 4.0 internal - ???