From: Paul Brannan <paul@...>
Date: 2002-01-11T06:55:50+09:00
Subject: Re: Hexadecimal float (Re: regexen for strings that can be converted to numbers)

On Fri, Jan 11, 2002 at 02:59:41AM +0900, nobu.nokada@softhome.net wrote:
> strtod() on Linux (or glibc) seems to accept radix prefix.
> Is this Linux specific?  Also intended?

From the C standard, section 7.20.1.3:
  3 The expected form of the subject sequence is an optional plus or
    minus sign, then one of the following:
    - a nonempty sequence of decimal digits optionally containing a
      decimal-point character, then an optional exponent part as defined
      in 6.4.4.2;
    - a 0x or 0X, then a nonempty sequence of hexadecimal digits
      optionally containing a decimal-point character, then an optional
      binary exponent part as defined in 6.4.4.2;
    - one of INF or INFINITY, ignoring case
    - one of NAN or NAN(n-char-sequence opt ), ignoring case in the NAN
      part, where: n-char-sequence: digit nondigit n-char-sequence digit
      n-char-sequence nondigit
    The subject sequence is defined as the longest initial subsequence
    of the input string, starting with the first non-white-space
    character, that is of the expected form. The subject sequence
    contains no characters if the input string is not of the expected
    form.