Converts the argument, a wide character, to uppercase. If the
argument is not a lowercase character, it is returned unchanged.
Format
#include <wctype.h> (ISO C)
#include <wchar.h> (XPG4)
int towupper (wint_t wc);
1 – Argument
wc
An object of type wint_t representable as a valid wide character
in the current locale, or the value of WEOF. For any other value,
the behavior is undefined.
2 – Description
If the argument is a lowercase wide character, the corresponding
uppercase wide character (as defined in the LC_CTYPE category of
the locale) is returned, if it exists. If it does not exist, the
function returns the input argument unchanged.