+++ /dev/null
-.\" Copyright (c) 1990, 1991 The Regents of the University of California.
-.\" All rights reserved.
-.\"
-.\" This code is derived from software contributed to Berkeley by
-.\" the American National Standards Committee X3, on Information
-.\" Processing Systems.
-.\"
-.\" %%%LICENSE_START(BSD_4_CLAUSE_UCB)
-.\" Redistribution and use in source and binary forms, with or without
-.\" modification, are permitted provided that the following conditions
-.\" are met:
-.\" 1. Redistributions of source code must retain the above copyright
-.\" notice, this list of conditions and the following disclaimer.
-.\" 2. Redistributions in binary form must reproduce the above copyright
-.\" notice, this list of conditions and the following disclaimer in the
-.\" documentation and/or other materials provided with the distribution.
-.\" 3. All advertising materials mentioning features or use of this software
-.\" must display the following acknowledgement:
-.\" This product includes software developed by the University of
-.\" California, Berkeley and its contributors.
-.\" 4. Neither the name of the University nor the names of its contributors
-.\" may be used to endorse or promote products derived from this software
-.\" without specific prior written permission.
-.\"
-.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
-.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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-.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
-.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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-.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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-.\" %%%LICENSE_END
-.\"
-.\" @(#)strtod.3 5.3 (Berkeley) 6/29/91
-.\"
-.\" Modified Sun Aug 21 17:16:22 1994 by Rik Faith (faith@cs.unc.edu)
-.\" Modified Sat May 04 19:34:31 MET DST 1996 by Michael Haardt
-.\" (michael@cantor.informatik.rwth-aachen.de)
-.\" Added strof, strtold, aeb, 2001-06-07
-.\"
-.TH STRTOD 3 2014-08-19 "Linux" "Linux Programmer's Manual"
-.SH NAME
-strtod, strtof, strtold \- convert ASCII string to floating-point number
-.SH SYNOPSIS
-.B #include <stdlib.h>
-.sp
-.BI "double strtod(const char *" nptr ", char **" endptr );
-.br
-.BI "float strtof(const char *" nptr ", char **" endptr );
-.br
-.BI "long double strtold(const char *" nptr ", char **" endptr );
-.sp
-.in -4n
-Feature Test Macro Requirements for glibc (see
-.BR feature_test_macros (7)):
-.in
-.ad l
-.sp
-.BR strtof (),
-.BR strtold ():
-.RS 4
-_XOPEN_SOURCE\ >=\ 600 || _ISOC99_SOURCE ||
-_POSIX_C_SOURCE\ >=\ 200112L;
-.br
-or
-.I cc\ -std=c99
-.RE
-.ad
-.SH DESCRIPTION
-The
-.BR strtod (),
-.BR strtof (),
-and
-.BR strtold ()
-functions convert the initial portion of the string pointed to by
-.I nptr
-to
-.IR double ,
-.IR float ,
-and
-.I long double
-representation, respectively.
-
-The expected form of the (initial portion of the) string is
-optional leading white space as recognized by
-.BR isspace (3),
-an optional plus (\(aq+\(aq) or minus sign (\(aq\-\(aq) and then either
-(i) a decimal number, or (ii) a hexadecimal number,
-or (iii) an infinity, or (iv) a NAN (not-a-number).
-.LP
-A
-.I "decimal number"
-consists of a nonempty sequence of decimal digits
-possibly containing a radix character (decimal point, locale-dependent,
-usually \(aq.\(aq), optionally followed by a decimal exponent.
-A decimal exponent consists of an \(aqE\(aq or \(aqe\(aq, followed by an
-optional plus or minus sign, followed by a nonempty sequence of
-decimal digits, and indicates multiplication by a power of 10.
-.LP
-A
-.I "hexadecimal number"
-consists of a "0x" or "0X" followed by a nonempty sequence of
-hexadecimal digits possibly containing a radix character,
-optionally followed by a binary exponent.
-A binary exponent
-consists of a \(aqP\(aq or \(aqp\(aq, followed by an optional
-plus or minus sign, followed by a nonempty sequence of
-decimal digits, and indicates multiplication by a power of 2.
-At least one of radix character and binary exponent must be present.
-.LP
-An
-.I infinity
-is either "INF" or "INFINITY", disregarding case.
-.LP
-A
-.I NAN
-is "NAN" (disregarding case) optionally followed by a string,
-.IR (n-char-sequence) ,
-where
-.IR n-char-sequence
-specifies in an implementation-dependent
-way the type of NAN (see NOTES).
-.SH RETURN VALUE
-These functions return the converted value, if any.
-
-If
-.I endptr
-is not NULL,
-a pointer to the character after the last character used in the conversion
-is stored in the location referenced by
-.IR endptr .
-
-If no conversion is performed, zero is returned and the value of
-.I nptr
-is stored in the location referenced by
-.IR endptr .
-
-If the correct value would cause overflow, plus or minus
-.B HUGE_VAL
-.RB ( HUGE_VALF ,
-.BR HUGE_VALL )
-is returned (according to the sign of the value), and
-.B ERANGE
-is stored in
-.IR errno .
-If the correct value would cause underflow, zero is
-returned and
-.B ERANGE
-is stored in
-.IR errno .
-.SH ERRORS
-.TP
-.B ERANGE
-Overflow or underflow occurred.
-.SH ATTRIBUTES
-.SS Multithreading (see pthreads(7))
-The
-.BR strtod (),
-.BR strtof (),
-and
-.BR strtold ()
-functions are thread-safe with exceptions.
-These functions can be safely used in multithreaded applications,
-as long as
-.BR setlocale (3)
-is not called to change the locale during their execution.
-.SH CONFORMING TO
-C89 describes
-.BR strtod (),
-C99
-describes the other two functions.
-.SH NOTES
-Since
-0 can legitimately be returned
-on both success and failure, the calling program should set
-.I errno
-to 0 before the call,
-and then determine if an error occurred by checking whether
-.I errno
-has a nonzero value after the call.
-
-In the glibc implementation, the
-.IR n-char-sequence
-that optionally follows "NAN"
-is interpreted as an integer number
-(with an optional '0' or '0x' prefix to select base 8 or 16)
-that is to be placed in the
-mantissa component of the returned value.
-.\" From glibc 2.8's stdlib/strtod_l.c:
-.\" We expect it to be a number which is put in the
-.\" mantissa of the number.
-.\" It looks as though at least FreeBSD (according to the manual) does
-.\" something similar.
-.\" C11 says: "An implementation may use the n-char sequence to determine
-.\" extra information to be represented in the NaN's significant."
-.SH EXAMPLE
-See the example on the
-.BR strtol (3)
-manual page;
-the use of the functions described in this manual page is similar.
-.SH SEE ALSO
-.BR atof (3),
-.BR atoi (3),
-.BR atol (3),
-.BR nan (3),
-.BR nanf (3),
-.BR nanl (3),
-.BR strtol (3),
-.BR strtoul (3)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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