xref: /freebsd/lib/libc/stdlib/atoi.3 (revision 6bfca4dcab07dad45a805879d954876b353c0810)
1.\" Copyright (c) 1990, 1991, 1993
2.\"	The Regents of the University of California.  All rights reserved.
3.\"
4.\" This code is derived from software contributed to Berkeley by
5.\" the American National Standards Committee X3, on Information
6.\" Processing Systems.
7.\"
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. Neither the name of the University nor the names of its contributors
17.\"    may be used to endorse or promote products derived from this software
18.\"    without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
32.Dd April 1, 2020
33.Dt ATOI 3
34.Os
35.Sh NAME
36.Nm atoi
37.Nd convert
38.Tn ASCII
39string to integer
40.Sh LIBRARY
41.Lb libc
42.Sh SYNOPSIS
43.In stdlib.h
44.Ft int
45.Fn atoi "const char *nptr"
46.Sh DESCRIPTION
47The
48.Fn atoi
49function converts the initial portion of the string pointed to by
50.Fa nptr
51to
52.Vt int
53representation.
54.Pp
55It is equivalent to:
56.Bd -literal -offset indent
57(int)strtol(nptr, NULL, 10);
58.Ed
59.Pp
60The
61.Fn atoi
62function has been deprecated by
63.Fn strtol
64and should not be used in new code.
65.Sh ERRORS
66The function
67.Fn atoi
68need not affect the value of
69.Va errno
70on an error.
71.Sh SEE ALSO
72.Xr atof 3 ,
73.Xr atol 3 ,
74.Xr strtod 3 ,
75.Xr strtol 3 ,
76.Xr strtoul 3
77.Sh STANDARDS
78The
79.Fn atoi
80function conforms to
81.St -p1003.1-90 ,
82.St -isoC ,
83and
84.St -isoC-99 .
85.Sh HISTORY
86The
87.Fn atoi
88function appeared in
89.At v1 .
90