1.\" Copyright (c) 1991 The Regents of the University of California. 2.\" 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.\" $OpenBSD: atof.3,v 1.9 2019/01/16 12:55:49 schwarze Exp $ 33.\" 34.Dd $Mdocdate: January 16 2019 $ 35.Dt ATOF 3 36.Os 37.Sh NAME 38.Nm atof 39.Nd convert ASCII string to double 40.Sh SYNOPSIS 41.In stdlib.h 42.Ft double 43.Fn atof "const char *nptr" 44.Sh DESCRIPTION 45The 46.Fn atof 47function converts the initial portion of the string pointed to by 48.Fa nptr 49to 50.Li double 51representation. 52.Pp 53It is equivalent to: 54.Bd -literal -offset indent 55strtod(nptr, (char **)NULL); 56.Ed 57.Sh SEE ALSO 58.Xr atoi 3 , 59.Xr atol 3 , 60.Xr strtod 3 , 61.Xr strtol 3 , 62.Xr strtoul 3 63.Sh STANDARDS 64The 65.Fn atof 66function conforms to 67.St -ansiC . 68.Sh HISTORY 69An 70.Fn atof 71function first appeared in 72.At v1 . 73.Sh CAVEATS 74On systems other than 75.Ox , 76the 77.Dv LC_NUMERIC 78.Xr locale 1 79category can cause parsing failures; see CAVEATS in 80.Xr setlocale 3 81for details. 82