100 lines
3.2 KiB
Groff
100 lines
3.2 KiB
Groff
.\" Copyright (c) 1991, 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" This code is derived from software contributed to Berkeley by
|
|
.\" the American National Standards Committee X3, on Information
|
|
.\" Processing Systems.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. All advertising materials mentioning features or use of this software
|
|
.\" must display the following acknowledgement:
|
|
.\" This product includes software developed by the University of
|
|
.\" California, Berkeley and its contributors.
|
|
.\" 4. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" @(#)isdigit.3 8.1 (Berkeley) 6/4/93
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd October 6, 2002
|
|
.Dt ISDIGIT 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm isdigit, isnumber
|
|
.Nd decimal-digit character test
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.In ctype.h
|
|
.Ft int
|
|
.Fn isdigit "int c"
|
|
.Ft int
|
|
.Fn isnumber "int c"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn isdigit
|
|
function tests for any decimal-digit character.
|
|
For any locale,
|
|
this includes the following characters only:
|
|
.Pp
|
|
.Bl -column \&``0''______ \&``0''______ \&``0''______ \&``0''______ \&``0''______
|
|
.It "\&``0''\t``1''\t``2''\t``3''\t``4''"
|
|
.It "\&``5''\t``6''\t``7''\t``8''\t``9''"
|
|
.El
|
|
.Pp
|
|
For single C
|
|
.Va char Ns s
|
|
locales (see
|
|
.Xr multibyte 3 )
|
|
the value of the argument is
|
|
representable as an
|
|
.Li unsigned char
|
|
or the value of
|
|
.Dv EOF .
|
|
.Sh RETURN VALUES
|
|
The
|
|
.Fn isdigit
|
|
function returns zero if the character tests false and
|
|
returns non-zero if the character tests true.
|
|
.Sh COMPATIBILITY
|
|
Although
|
|
.Fn isdigit
|
|
accepts arguments outside of the range of the
|
|
.Vt "unsigned char"
|
|
type in locales with large character sets,
|
|
this is a
|
|
.Bx 4.4
|
|
extension and the
|
|
.Fn iswdigit
|
|
function should be used instead for maximum portability.
|
|
.Sh SEE ALSO
|
|
.Xr ctype 3 ,
|
|
.Xr iswdigit 3 ,
|
|
.Xr multibyte 3 ,
|
|
.Xr ascii 7
|
|
.Sh STANDARDS
|
|
The
|
|
.Fn isdigit
|
|
function conforms to
|
|
.St -isoC .
|