iswdigit - test for decimal digit wide character
Standard C library (libc
, -lc
)
#include <wctype.h>
int iswdigit(wint_t wc);
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'.
The iswdigit() function returns nonzero if
wc
is a wide character belonging to the wide-character class
"digit". Otherwise, it returns zero.
For an explanation of the terms used in this section, see attributes(7).
Interface | Attribute | Value |
iswdigit() |
Thread safety | MT-Safe locale |
C11, POSIX.1-2008.
POSIX.1-2001, C99.
The behavior of iswdigit() depends on the LC_CTYPE category of the current locale.