ctypes_diff_py23.txt

If you happen to meet dat structure problem, please read rabinpoly.py and pat attention
to following difference. 

            ctypes type     C type                                  Python type

Python 2    c_char          char                                    1-character string
Python 3    c_char          char                                    1-character bytes object

Python 2    c_wchar         wchar_t                                 1-character unicode string
Python 3    c_wchar         wchar_t                                 1-character string

Python 2    c_char_p        char * (NUL terminated)                 string or None
Python 3    c_char_p        char * (NUL terminated)                 bytes object or None

Python 2    c_wchar_p       wchar_t * (NUL terminated)              unicode or None
Python 3    c_wchar_p       wchar_t * (NUL terminated)              string or None