Notes about IPv6 support in INN:

   These notes were last updated on 2014-09-17.

   Note that starting from INN 2.6.0, IPv6 is unconditionally enabled, when
   available.  The --enable-ipv6 configure flag no longer exists.

   This document contains some notes about the status of IPv6 support in
   INN (see also the parts of the code marked FIXME):


Some comments as of the completion of the original patch:

    Date: Wed, 13 Feb 2002 00:10:59 -0500 (EST)
    From: Nathan Lutchansky <lutchann@litech.org>
    To: Jeffrey M. Vinocur <jeff@litech.org>
    Subject: IPv6 patch notes

    The IPv6 patch is based directly on Marco d'Itri's IPv6 patch of
    2001-03-01 that was posted last year to the inn-workers list.  The
    patch applied fairly cleanly to a working copy from 2002-02-04, and
    the resulting tree was used as the basis for my work.

    Modifications by Marco and myself were made so that if IPv6 support is
    not explicitly enabled with the --enable-ipv6 flag to the configure
    script, the old networking code will be used.  Hopefully, nobody will
    notice any problems with the default configuration, although some
    changes have been made to data structures even when IPv6 is disabled.

    The original patch added IPv6 support to innd and inndstart, and the
    auth_pass program.  I have added support to nnrpd, innfeed, and the
    ident auth program.  There is no IPv6 support for imapfeed and other
    auxiliary programs like the radius auth backend.

    Marco's patch made use of several preprocessor defines for
    configuration but the defines were hand-coded, so I added the
    corresponding tests the the configuration script.  I make no
    guarantees that the configure script will catch all possible
    non-portable behavior; the IPv6 API standardization process has left
    quite a wake of incompatible API implementations over the years.
    -Nathan
