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'\" t
.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
.\"
.\" SPDX-License-Identifier: Linux-man-pages-copyleft
.\"
.\" References consulted:
.\" Linux libc source code
.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
.\" 386BSD man pages
.\" Modified Mon Mar 29 22:39:24 1993, David Metcalfe
.\" Modified Sat Jul 24 21:39:22 1993, Rik Faith (faith@cs.unc.edu)
.TH atof 3 2023-07-20 "Linux man-pages 6.05.01"
.SH NAME
atof \- convert a string to a double
.SH LIBRARY
Standard C library
.RI ( libc ", " \-lc )
.SH SYNOPSIS
.nf
.B #include <stdlib.h>
.PP
.BI "double atof(const char *" nptr );
.fi
.SH DESCRIPTION
The
.BR atof ()
function converts the initial portion of the string
pointed to by \fInptr\fP to
.IR double .
The behavior is the same as
.PP
.in +4n
.EX
strtod(nptr, NULL);
.EE
.in
.PP
except that
.BR atof ()
does not detect errors.
.SH RETURN VALUE
The converted value.
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.TS
allbox;
lbx lb lb
l l l.
Interface Attribute Value
T{
.na
.nh
.BR atof ()
T} Thread safety MT-Safe locale
.TE
.sp 1
.SH STANDARDS
C11, POSIX.1-2008.
.SH HISTORY
POSIX.1-2001, C89, C99, SVr4, 4.3BSD.
.SH SEE ALSO
.BR atoi (3),
.BR atol (3),
.BR strfromd (3),
.BR strtod (3),
.BR strtol (3),
.BR strtoul (3)
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