xref: /freebsd/lib/libc/stdlib/atoi.3 (revision 783d3ff6d7fae619db8a7990b8a6387de0c677b5)
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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