iswdigit - test for decimal digit wide character

       For an explanation of the terms used in this section, see attributes(7).
       ┌──────────────────────────────────────────────────────────────────────┬───────────────┬────────────────┐
       │ Interface                                                            │ Attribute     │ Value          │
       ├──────────────────────────────────────────────────────────────────────┼───────────────┼────────────────┤
       │ iswdigit()                                                           │ Thread safety │ MT-Safe locale │
       └──────────────────────────────────────────────────────────────────────┴───────────────┴────────────────┘

       The iswdigit() function is the wide-character equivalent of the isdigit(3) function.  It tests whether wc
       is a wide character belonging to the wide-character class "digit".

       The wide-character class "digit" is a subclass of the wide-character class "xdigit", and therefore also a
       subclass  of  the  wide-character  class  "alnum",  of  the wide-character class "graph" and of the wide-
       character class "print".

       Being a subclass of the wide character class "print", the wide-character class "digit" is  disjoint  from
       the wide-character class "cntrl".

       Being  a  subclass of the wide-character class "graph", the wide-character class "digit" is disjoint from
       the wide-character class "space" and its subclass "blank".

       Being a subclass of the wide-character class "alnum", the wide-character class "digit" is  disjoint  from
       the wide-character class "punct".

       The  wide-character  class  "digit"  is disjoint from the wide-character class "alpha" and therefore also
       disjoint from its subclasses "lower", "upper".

       The wide-character class "digit" always contains exactly the digits '0' to '9'.

       POSIX.1-2001, C99.

       Standard C library (libc, -lc)

       iswdigit - test for decimal digit wide character

       The behavior of iswdigit() depends on the LC_CTYPE category of the current locale.

       The iswdigit() function returns nonzero if wc is a wide character belonging to the  wide-character  class
       "digit".  Otherwise, it returns zero.

isdigit(3), iswctype(3)

Linux man-pages 6.9.1                              2024-05-02                                        iswdigit(3)

       C11, POSIX.1-2008.

#include<wctype.h>intiswdigit(wint_twc);