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ISWDIGIT

Section: Linux Programmer's Manual (3)
Updated: 2015-08-08
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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(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 aq0aq to aq9aq.

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).

Interface	Attribute	Value
iswdigit()	Thread safety	MT-Safe locale

CONFORMING TO

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

NOTES

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

COLOPHON

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