NAME
strtod —
convert ASCII string to
double
SYNOPSIS
#include
<stdlib.h>
double
strtod(const
char *nptr, char
**endptr);
DESCRIPTION
Thestrtod()
function converts the initial portion of the string pointed to by
nptr to
double
representation.
The expected form of the string is an optional plus (``+'') or minus sign (``-'') followed by a sequence of digits optionally containing a decimal-point character, optionally followed by an exponent. An exponent consists of an ``E'' or ``e'', followed by an optional plus or minus sign, followed by a sequence of digits.
Leading white-space characters in the string (as defined by the isspace(3) function) are skipped.
RETURN VALUES
The strtod() function returns the
converted value, if any.
If endptr is not
NULL, a pointer to the character after the last
character used in the conversion is stored in the location referenced by
endptr.
If no conversion is performed, zero is returned and the value of nptr is stored in the location referenced by endptr.
If the correct value would cause overflow, plus or minus
HUGE_VAL is returned (according to the sign of the
value), and ERANGE is stored in
errno. If the correct value would cause underflow,
zero is returned and ERANGE is stored in
errno.
ERRORS
- [
ERANGE] - Overflow or underflow occurred.
SEE ALSO
STANDARDS
The strtod() function conforms to
ANSI X3.159-1989
(“ANSI C89”).
AUTHORS
The author of this software is David M. Gay.
Copyright (c) 1991 by AT&T.
Permission to use, copy, modify, and distribute this software for any purpose without fee is hereby granted, provided that this entire notice is included in all copies of any software which is or includes a copy or modification of this software and in all copies of the supporting documentation for such software.
THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED WARRANTY. IN PARTICULAR, NEITHER THE AUTHOR NOR AT&T MAKES ANY REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
Contact your vendor for a free copy of the source code to
strtod() and accompanying functions.