Libc-1353.100.2.tar.gz

[apple/libc.git] / stdlib / FreeBSD / atoi.3

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.\"     @(#)atoi.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: src/lib/libc/stdlib/atoi.3,v 1.14 2007/10/19 06:23:39 davidxu Exp $
.\"
.Dd June 4, 1993
.Dt ATOI 3
.Os
.Sh NAME
.Nm atoi ,
.Nm atoi_l
.Nd convert
.Tn ASCII
string to integer
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In stdlib.h
.Ft int
.Fn atoi "const char *str"
.In xlocale.h
.Ft int
.Fn atoi_l "const char *str" "locale_t loc"
.Sh DESCRIPTION
The
.Fn atoi
function converts the initial portion of the string pointed to by
.Fa str
to
.Vt int
representation.
.Pp
It is equivalent to:
.Bd -literal -offset indent
(int)strtol(str, (char **)NULL, 10);
.Ed
.Pp
While the
.Fn atoi
function uses the current locale, the
.Fn atoi_l
function may be passed a locale directly. See
.Xr xlocale 3
for more information.
.Sh IMPLEMENTATION NOTES
The
.Fn atoi
and
.Fn atoi_l
functions are thread-safe and async-cancel-safe.
.Pp
The
.Fn strtol
and
.Fn strtol_l
functions are recommended instead of 
.Fn atoi
and
.Fn atoi_l
functions, especially in new code.
.Sh ERRORS
The function
.Fn atoi
need not affect the value of
.Va errno
on an error.
.Sh SEE ALSO
.Xr atof 3 ,
.Xr atol 3 ,
.Xr strtod 3 ,
.Xr strtol 3 ,
.Xr strtoul 3 ,
.Xr xlocale 3
.Sh STANDARDS
The
.Fn atoi
function conforms to
.St -p1003.1-90 ,
.St -isoC ,
and
.St -isoC-99 .