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`iswspace'--wide-character space test

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