redhat man page for iswdigit

ISWDIGIT(3)						     Linux Programmer's Manual						       ISWDIGIT(3)

NAME
       iswdigit - test for decimal digit wide character

SYNOPSIS
       #include <wctype.h>

       int iswdigit(wint_t wc);

DESCRIPTION
       The  iswdigit  function	is the wide-character equivalent of the isdigit 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'.

RETURN VALUE
       The iswdigit function returns non-zero if wc is a wide character belonging to the wide character class "digit". Otherwise it returns zero.

CONFORMING TO
       ISO/ANSI C, UNIX98

SEE ALSO
       isdigit(3), iswctype(3)

NOTES
       The behaviour of iswdigit depends on the LC_CTYPE category of the current locale.

GNU
								    1999-07-25							       ISWDIGIT(3)