[apple/libc.git] / locale / FreeBSD / isdigit.3

.\" 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: src/lib/libc/locale/isdigit.3,v 1.19 2004/08/21 07:37:08 tjr Exp $
.\"
.Dd August 21, 2004
.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 a decimal digit character.
Regardless of 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
The
.Fn isnumber
function behaves similarly to
.Fn isdigit ,
but may recognize additional characters, depending on the current locale
setting.
.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
and
.Fn isnumber
functions return zero if the character tests false and
returns non-zero if the character tests true.
.Sh COMPATIBILITY
The
.Bx 4.4
extension of accepting arguments outside of the range of the
.Vt "unsigned char"
type in locales with large character sets is considered obsolete
and may not be supported in future releases.
The
.Fn iswdigit
function should be used instead.
.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 .
.Sh HISTORY
The
.Fn isnumber
function appeared in
.Bx 4.4 .
Commit	Line	Data
e9ce8d39 A	1	.\" Copyright (c) 1991, 1993
	2	.\" The Regents of the University of California. All rights reserved.
	3	.\"
5b2abdfb A	4	.\" This code is derived from software contributed to Berkeley by
	5	.\" the American National Standards Committee X3, on Information
	6	.\" Processing Systems.
	7	.\"
e9ce8d39 A	8	.\" Redistribution and use in source and binary forms, with or without
	9	.\" modification, are permitted provided that the following conditions
	10	.\" are met:
	11	.\" 1. Redistributions of source code must retain the above copyright
	12	.\" notice, this list of conditions and the following disclaimer.
	13	.\" 2. Redistributions in binary form must reproduce the above copyright
	14	.\" notice, this list of conditions and the following disclaimer in the
	15	.\" documentation and/or other materials provided with the distribution.
	16	.\" 3. All advertising materials mentioning features or use of this software
	17	.\" must display the following acknowledgement:
	18	.\" This product includes software developed by the University of
	19	.\" California, Berkeley and its contributors.
	20	.\" 4. Neither the name of the University nor the names of its contributors
	21	.\" may be used to endorse or promote products derived from this software
	22	.\" without specific prior written permission.
	23	.\"
	24	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	25	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	26	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	27	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	28	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	29	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	30	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	31	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	32	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	33	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	34	.\" SUCH DAMAGE.
	35	.\"
5b2abdfb	36	.\" @(#)isdigit.3 8.1 (Berkeley) 6/4/93
3d9156a7	37	.\" $FreeBSD: src/lib/libc/locale/isdigit.3,v 1.19 2004/08/21 07:37:08 tjr Exp $
e9ce8d39	38	.\"
3d9156a7	39	.Dd August 21, 2004
5b2abdfb	40	.Dt ISDIGIT 3
e9ce8d39 A	41	.Os
e9ce8d39 A	42	.Sh NAME
9385eb3d	43	.Nm isdigit, isnumber
5b2abdfb	44	.Nd decimal-digit character test
e9ce8d39 A	45	.Sh LIBRARY
	46	.Lb libc
	47	.Sh SYNOPSIS
5b2abdfb	48	.In ctype.h
e9ce8d39	49	.Ft int
5b2abdfb	50	.Fn isdigit "int c"
9385eb3d A	51	.Ft int
9385eb3d A	52	.Fn isnumber "int c"
e9ce8d39 A	53	.Sh DESCRIPTION
e9ce8d39 A	54	The
5b2abdfb	55	.Fn isdigit
3d9156a7 A	56	function tests for a decimal digit character.
3d9156a7 A	57	Regardless of locale, this includes the following characters only:
9385eb3d A	58	.Pp
	59	.Bl -column \&``0''______ \&``0''______ \&``0''______ \&``0''______ \&``0''______
	60	.It "\&``0''\t``1''\t``2''\t``3''\t``4''"
	61	.It "\&``5''\t``6''\t``7''\t``8''\t``9''"
	62	.El
	63	.Pp
3d9156a7 A	64	The
	65	.Fn isnumber
	66	function behaves similarly to
	67	.Fn isdigit ,
	68	but may recognize additional characters, depending on the current locale
	69	setting.
	70	.Pp
5b2abdfb A	71	For single C
	72	.Va char Ns s
	73	locales (see
	74	.Xr multibyte 3 )
	75	the value of the argument is
	76	representable as an
	77	.Li unsigned char
	78	or the value of
	79	.Dv EOF .
e9ce8d39	80	.Sh RETURN VALUES
5b2abdfb A	81	The
5b2abdfb A	82	.Fn isdigit
3d9156a7 A	83	and
	84	.Fn isnumber
	85	functions return zero if the character tests false and
5b2abdfb	86	returns non-zero if the character tests true.
9385eb3d	87	.Sh COMPATIBILITY
3d9156a7	88	The
9385eb3d	89	.Bx 4.4
3d9156a7 A	90	extension of accepting arguments outside of the range of the
	91	.Vt "unsigned char"
	92	type in locales with large character sets is considered obsolete
	93	and may not be supported in future releases.
	94	The
9385eb3d	95	.Fn iswdigit
3d9156a7	96	function should be used instead.
e9ce8d39	97	.Sh SEE ALSO
5b2abdfb	98	.Xr ctype 3 ,
9385eb3d	99	.Xr iswdigit 3 ,
5b2abdfb A	100	.Xr multibyte 3 ,
	101	.Xr ascii 7
	102	.Sh STANDARDS
e9ce8d39	103	The
5b2abdfb A	104	.Fn isdigit
	105	function conforms to
	106	.St -isoC .
3d9156a7 A	107	.Sh HISTORY
	108	The
	109	.Fn isnumber
	110	function appeared in
	111	.Bx 4.4 .