INT 21 - DOS 2+ - "CWD" - GET CURRENT DIRECTORY
AH = 47h
DL = drive number (00h = default, 01h = A:, etc)
DS:SI -> 64-byte buffer for ASCIZ pathname
Return: CF clear if successful
AX = 0100h (undocumented)
CF set on error
AX = error code (0Fh) (see AH=59h)
Notes:  the returned path does not include a drive or the initial backslash
many Microsoft products for Windows rely on AX being 0100h on success
under the FlashTek X-32 DOS extender, the buffer pointer is in DS:ESI
SeeAlso: AH=3Bh,INT 15/AX=DE25h

See also: 2119

2147 - DOS 2+ - "CWD" - GET CURRENT DIRECTORY