Availability:C-language interface function
pl_wchar_t* PL_atom_wchars(atom_t 
atom, int *len)Extract characters from a wide-character atom. Succeeds on any atom 
marked as `text'. If the underlying atom is a wide-character atom, the 
returned pointer is a pointer into the atom structure. If it is an 
ISO-Latin-1 character, the returned pointer comes from Prolog's `buffer 
ring' (see PL_get_chars()).