manpages.info - online man pages   

FreeBSD man pages : strtod (3)
STRTOD(3)	       FreeBSD Library Functions Manual 	     STRTOD(3)

NAME

strtod - convert ASCII string to double

LIBRARY

Standard C Library (libc, -lc)

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 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 con- sists 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 charac- ter 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

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

STANDARDS

The strtod() function conforms to ISO/IEC 9899:1990 (``ISO 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 docu- mentation 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 REPRESEN- TATION 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. FreeBSD 4.8 June 4, 1993 FreeBSD 4.8