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`wctype'--get wide-character classification type

     #include <wctype.h>
     wctype_t wctype(const char *C);
`wctype' is a function which takes a string C and gives back the
appropriate wctype_t type value associated with the string, if one
exists.  The following values are guaranteed to be recognized: "alnum",
"alpha", "blank", "cntrl", "digit", "graph", "lower", "print", "punct",
"space", "upper", and "xdigit".
`wctype' returns 0 and sets `errno' to `EINVAL' if the given name is
invalid.  Otherwise, it returns a valid non-zero wctype_t value.
`wctype' is C99.
   No supporting OS subroutines are required.