xref: /freebsd/lib/libc/stdlib/atoi.3 (revision 6829dae12bb055451fa467da4589c43bd03b1e64)
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32.\"     @(#)atoi.3	8.1 (Berkeley) 6/4/93
33.\" $FreeBSD$
34.\"
35.Dd June 13, 2018
36.Dt ATOI 3
37.Os
38.Sh NAME
39.Nm atoi
40.Nd convert
41.Tn ASCII
42string to integer
43.Sh LIBRARY
44.Lb libc
45.Sh SYNOPSIS
46.In stdlib.h
47.Ft int
48.Fn atoi "const char *nptr"
49.Sh DESCRIPTION
50The
51.Fn atoi
52function converts the initial portion of the string pointed to by
53.Fa nptr
54to
55.Vt int
56representation.
57.Pp
58It is equivalent to:
59.Bd -literal -offset indent
60(int)strtol(nptr, NULL, 10);
61.Ed
62.Pp
63The
64.Fn atoi
65function has been deprecated by
66.Fn strtol
67and should not be used in new code.
68.Sh ERRORS
69The function
70.Fn atoi
71need not affect the value of
72.Va errno
73on an error.
74.Sh SEE ALSO
75.Xr atof 3 ,
76.Xr atol 3 ,
77.Xr strtod 3 ,
78.Xr strtol 3 ,
79.Xr strtoul 3
80.Sh STANDARDS
81The
82.Fn atoi
83function conforms to
84.St -p1003.1-90 ,
85.St -isoC ,
86and
87.St -isoC-99 .
88