.\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
.\"
.\" This is free documentation; you can redistribute it and/or
.\" modify it under the terms of the GNU General Public License as
.\" published by the Free Software Foundation; either version 2 of
.\" the License, or (at your option) any later version.
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.\" References consulted:
.\"   GNU glibc-2 source code and manual
.\"   Dinkumware C library reference http://www.dinkumware.com/
.\"   OpenGroup's Single UNIX specification http://www.UNIX-systems.org/online.html
.\"   ISO/IEC 9899:1999
.\"
.TH ISWDIGIT 3  1999-07-25 "GNU" "Linux Programmer's Manual"
.SH NAME
iswdigit \- test for decimal digit wide character
.SH SYNOPSIS
.nf
.B #include <wctype.h>
.sp
.BI "int iswdigit(wint_t " wc );
.fi
.SH DESCRIPTION
The
.BR iswdigit ()
function is the wide-character equivalent of the
.BR isdigit (3)
function.
It tests whether \fIwc\fP is a wide character
belonging to the wide-character class "digit".
.PP
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".
.PP
Being a subclass of the wide character
class "print", the wide-character class
"digit" is disjoint from the wide-character class "cntrl".
.PP
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".
.PP
Being a subclass of the wide-character
class "alnum", the wide-character class
"digit" is disjoint from the wide-character class "punct".
.PP
The wide-character class "digit" is
disjoint from the wide-character class
"alpha" and therefore also disjoint from its subclasses "lower", "upper".
.PP
The wide-character class "digit" always
contains exactly the digits \(aq0\(aq to \(aq9\(aq.
.SH RETURN VALUE
The
.BR iswdigit ()
function returns nonzero
if \fIwc\fP is a wide character
belonging to the wide-character class "digit".
Otherwise it returns zero.
.SH CONFORMING TO
C99.
.SH NOTES
The behavior of
.BR iswdigit ()
depends on the
.B LC_CTYPE
category of the
current locale.
.SH SEE ALSO
.BR isdigit (3),
.BR iswctype (3)