INT 21 U - DOS 4+ internal - COUNTRY-DEPENDENT FILENAME CAPITALIZATION
AH = 65h
AL = function
A0h capitalize filename character
DL = character to capitalize
Return: DL = capitalized character
A1h capitalize counted filename string
DS:DX -> filename string to capitalize
CX = length of string
A2h capitalize ASCIZ filename
DS:DX -> ASCIZ filename to capitalize
Return: CF set on error
AX = error code (see AH=59h)
CF clear if successful
Note:   nonfunctional in DOS 4.00 through 5.00 due to a bug (the code sets a
pointer depending on the high bit of AL, but doesn't clear the
bit before branching by function number).


2165 - DOS 4+ internal - COUNTRY-DEPENDENT FILENAME CAPITALIZATION