problems with getaddrinfo() and _res.options

[Thorsten Kukuk]

On Sat, May 27, Ulrich Drepper wrote:

> Philip Blundell <Philip.Blundell@pobox.com> writes:
> 
> > >As a consequence of these changes getaddrinfo() now does not return
> > >the IPv4 and IPv6 address of a host if AF_UNSPEC is passed in as the
> > >protocol.  This is another change, but again a useful one.
> >
> > This will break all existing dual-stack applications.  Standard
> > practice up until now has been to use AF_UNSPEC and expect to get
> > back both IPv4 and IPv6 addresses.  (I think this is true for all
> > platforms, not just Linux.)
> 
> Why, it makes no sense.  If you can handle both, IPv4 and IPv6, why
> should you get the mapped IPv4 address back?  I just tried it on
> Solaris 8.  You only get the IPv4 address.

I don't think that Philip spoke about mapped IPv6 addresses.
If a host has a real IPv4 and a real IPv6 address, with AF_UNSPEC both 
addresses should give back, not only a IPv4 or IPv6.

  Thorsten

-- 
Thorsten Kukuk       http://www.suse.de/~kukuk/       kukuk@suse.de
SuSE GmbH            Schanzaeckerstr. 10            90443 Nuernberg
Linux is like a Vorlon.  It is incredibly powerful, gives terse,
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