xref: /freebsd/lib/libc/stdlib/atoi.3 (revision 2008043f386721d58158e37e0d7e50df8095942d)
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32.\"     @(#)atoi.3	8.1 (Berkeley) 6/4/93
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34.Dd April 1, 2020
35.Dt ATOI 3
36.Os
37.Sh NAME
38.Nm atoi
39.Nd convert
40.Tn ASCII
41string to integer
42.Sh LIBRARY
43.Lb libc
44.Sh SYNOPSIS
45.In stdlib.h
46.Ft int
47.Fn atoi "const char *nptr"
48.Sh DESCRIPTION
49The
50.Fn atoi
51function converts the initial portion of the string pointed to by
52.Fa nptr
53to
54.Vt int
55representation.
56.Pp
57It is equivalent to:
58.Bd -literal -offset indent
59(int)strtol(nptr, NULL, 10);
60.Ed
61.Pp
62The
63.Fn atoi
64function has been deprecated by
65.Fn strtol
66and should not be used in new code.
67.Sh ERRORS
68The function
69.Fn atoi
70need not affect the value of
71.Va errno
72on an error.
73.Sh SEE ALSO
74.Xr atof 3 ,
75.Xr atol 3 ,
76.Xr strtod 3 ,
77.Xr strtol 3 ,
78.Xr strtoul 3
79.Sh STANDARDS
80The
81.Fn atoi
82function conforms to
83.St -p1003.1-90 ,
84.St -isoC ,
85and
86.St -isoC-99 .
87.Sh HISTORY
88The
89.Fn atoi
90function appeared in
91.At v1 .
92