Converts a lowercase wide character to uppercase
#include <wctype.h> wint_t towupper ( wint_t wc );
The towupper( ) function is like toupper( ) in all respects, except that it operates on wide characters. An uppercase wide character is one for which iswupper( ) returns TRue in the current locale; a lowercase wide character is one for which iswlower( ) returns TRue.
See the example for mbrtowc( ) in this chapter.