iswdigit(3) Library Functions Manual iswdigit(3)
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 is-
digit(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-charac-
ter class "digit" is disjoint from the wide-character class "cntrl".
Being a subclass of the wide-character class "graph", the wide-charac-
ter 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-charac-
ter 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 be-
longing to the wide-character class "digit". Otherwise, it returns
zero.
ATTRIBUTES
For an explanation of the terms used in this section, see attrib-
utes(7).
┌────────────────────────────────────┬───────────────┬────────────────┐
│ Interface │ Attribute │ Value │
├────────────────────────────────────┼───────────────┼────────────────┤
│ iswdigit() │ Thread safety │ MT-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 cur-
rent locale.
SEE ALSO
isdigit(3), iswctype(3)
Linux man-pages 6.7 2023-10-31 iswdigit(3)
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