iswdigit - Online Linux Manual Page

Section : 3
Updated : 2023-02-05
Source : Linux man-pages 6.03

NAME

iswdigit − test for decimal digit wide character

LIBRARY

Standard C library

(

libc

−lc

)

SYNOPSIS

#include <wctype.h>

int iswdigit(wint_t

);

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 '0' to '9'.

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

STANDARDS

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

NOTES

The behavior of iswdigit(

)

depends on the LC_CTYPE category of the current locale.