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strtod(3C)							    strtod(3C)

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

SYNOPSIS
   IPF ONLY
DESCRIPTION
       returns,	as a double-precision floating-point number, the value	repre-
       sented  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	IPF  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 deci-
		   mal integer

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

       In  the hexadecimal form, the optionally	signed decimal integer follow-
       ing the or is interpreted as the	power of 2 by  which  the  significand
       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 re-
       turned.

       is equivalent to

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

   IPF ONLY
       is a version of it returns a result.

       is an version of	it returns an result.

       is equivalent to

EXTERNAL INFLUENCES
   Locale
       The category determines the value of the	 radix	character  within  the
       currently loaded	NLS environment.

APPLICATION USAGE
       To use (for IPF 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 ERANGE.

       If the correct value would be nonzero but too  small  in	 magnitude  to
       represent as a nonzero then returns zero	and sets to For	IPF, 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 IPF systems, these functions round correctly for  hexadecimal	 input
       strings,	 and  round correctly for up to	36 significant decimal 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)

NAME | SYNOPSIS | DESCRIPTION | EXTERNAL INFLUENCES | APPLICATION USAGE | RETURN VALUE | SEE ALSO | STANDARDS CONFORMANCE

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