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Name

iswdigit - test for decimal digit wide character

Library

Standard C library ( libc ", " -lc )

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 '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). allbox; lbx lb lb T{ iswdigit()
InterfaceAttributeValue
T}Thread safetyMT-Safe locale

Standards

C11, POSIX.1-2008.

History

POSIX.1-2001, C99.

Notes

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

See Also

  1. isdigit(3),
  2. iswctype(3)