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`iswgraph'--graphic wide-character test

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