hpux man page for atof

strtod(3C)																strtod(3C)

NAME
       strtod(), strtof(), strtold(), strtow(), strtoq(), atof() - convert string to floating-point number

SYNOPSIS
   Itanium(R)-based Systems Only
DESCRIPTION
       returns,  as  a	double-precision  floating-point  number,  the value represented by the character string pointed to by str.  The string is
       scanned (leading white-space characters as defined by in ctype(3C) are ignored) up to the first unrecognized character.	If  no	conversion
       can take place, zero is returned.

       recognizes characters in the following sequence:

	      1.   An optional string of white space characters which are ignored
	      2.   An optional sign

       and one of the following:

	      3.   A  string  of digits optionally containing a radix character, followed by an optional or followed by an optional sign or space,
		   followed by an integer
	      4.   One of or ignoring case
	      5.   ignoring case
	      6.   For Itanium-based system only: or then a nonempty sequence of hexadecimal digits optionally containing a radix character,  then
		   a or followed by an optional sign or space, followed by a decimal integer

       The radix character is determined by the loaded environment (see setlocale(3C)).  If has not been called successfully, the default environ-
       ment, "C", is used (see lang(5)).  The default environment specifies a period as the radix character.

       In the hexadecimal form, the optionally signed decimal integer following the or is interpreted as the power of 2 by which  the  significant
       part is to be scaled.

       If  the value of ptr is not the variable to which it points is set to point at the character after the last number, if any, that was recog-
       nized.  If no number can be formed, is set to str, and zero is returned.

       is equivalent to

       is a version of it returns a result.  For PA-RISC and for Itanium-based systems, if the user has defined the result type is declared  as  a
       instead of as a The declaration with a is obsolescent.

   Itanium-based Systems Only
       is a version of it returns a result.

       is an version of it returns an result.

       is equivalent to

EXTERNAL INFLUENCES
   Environment Variables
       determines the value of the radix character within the currently loaded environment.

APPLICATION USAGE
       To use (for Itanium-based systems) or compile with the option.

RETURN VALUE
       If the correct value would cause overflow, returns (equal to according to the sign of the value, and sets to

       If  the correct value would be nonzero but too small in magnitude to represent as a nonzero then returns zero and sets to For Itanium-based
       system, also sets to whenever the conversion of its input parameter character string to raises the underflow exception.

       When the input parameter character string for after the optional white space and sign, is either (case insensitive) or  (case  insensitive)
       will return according to the sign indicated by the character string.

       When the input parameter character string for after the optional white space and sign, is (case insensitive), will return a quiet NaN.

       On Itanium-based systems, these functions round correctly for hexadecimal input strings, and round correctly for up to 36 significant deci-
       mal digits, according to the specification in ISO/IEC C99.

SEE ALSO
       ctype(3C), setlocale(3C), scanf(3S), strtol(3C), lang(5), thread_safety(5).

STANDARDS CONFORMANCE
																	strtod(3C)