std::ctype<CharT>::toupper,std::ctype<CharT>::do_toupper (3) - Linux Manuals
Defined in header <locale>
CharT toupper( CharT c ) const;
const CharT* toupper( CharT* beg, const CharT* end ) const;
virtual CharT do_toupper( CharT c ) const;
virtual const CharT* do_toupper( CharT* beg, const CharT* end ) const;
1,2) public member function, calls the protected virtual member function do_toupper of the most derived class.
3) Converts the character c to upper case if an upper case form is defined by this locale.
4) For every character in the character array [beg, end), for which an upper case form exists, replaces the character with that upper case form.
c - character to convert
beg - pointer to the first character in an array of characters to convert
end - one past the end pointer for the array of characters to convert
1,3) upper case character or c if no upper case form is listed by this locale.
Only 1:1 character mapping can be performed by this function, e.g. the uppercase form of 'ß' is (with some exceptions) the two-character string "SS", which cannot be obtained by do_toupper.
// Run this code
tolower (public member function)