DESCRIPTION

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 _zsingle_quotesz_0_zsingle_quotesz_ to _zsingle_quotesz_9_zsingle_quotesz_.

RETURN VALUE

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

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

CONFORMING TO

POSIX.1-2001, POSIX.1-2008, C99.

NOTES

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

SEE ALSO

isdigit(3), iswctype(3)