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STRTOD(3) Library functions STRTOD(3)

NAME

strtod - convert ASCII string to double

SYNOPSIS

#include <stdlib.h>

double strtod(const char *nptr, char **endptr);

DESCRIPTION

The strtod() function converts the initial portion of the string pointed to by nptr to double representation.

The expected form of the string is optional leading white space as checked by isspace(3), 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 non-empty sequence of digits. If the locale is not "C" or "POSIX", different formats may be used.

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

Overflow or underflow occurred.

CONFORMING TO

ANSI C

SEE ALSO

atof(3), atoi(3), atol(3), strtol(3), strtoul(3)

March 4th, 1996 BSD Manual Page