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`iswupper'--upper-case wide-character test

     #include <wctype.h>
     int iswupper(wint_t C);
`iswupper' is a function which classifies wide-character values that
have an upper-case translation.
`iswupper' returns non-zero if C is a upper-case wide-character.
`iswupper' is C99.
   No supporting OS subroutines are required.