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  option-
     ally  containing  a decimal-point character, optionally fol-
     lowed 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 loca-
     tion 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.

CONFORMING TO

     ANSI C

SEE ALSO

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