Originální popis anglicky:
iswdigit - test for decimal digit wide character
Návod, kniha: Linux Programmer's Manual
#include <wctype.h>
int iswdigit(wint_t wc);
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'.
The
iswdigit function returns non-zero if
wc is a wide character
belonging to the wide character class "digit". Otherwise it returns
zero.
ISO/ANSI C, UNIX98
isdigit(3),
iswctype(3)
The behaviour of
iswdigit depends on the LC_CTYPE category of the current
locale.
