Re: pg_upgrade - add config directory setting

Bruce Momjian wrote:
> Tom Lane wrote:
> > Bruce Momjian <bruce@momjian.us> writes:
> > > Tom Lane wrote:
> > >> Yeah.  I think the only sensible way to do this would be to provide an
> > >> operating mode for the postgres executable that would just parse the
> > >> config file and spit out requested values.
> > 
> > > That would certainly solve the problem, though it would have to be
> > > backpatched all the way back to 8.4, and it would require pg_upgrade
> > > users to be on newer minor versions of Postgres.
> > 
> > I would just say "no" to people who expect this to work against older
> > versions of Postgres.  I think it's sufficient if we get this into HEAD
> > so that it will work in the future.
> 
> Well, it is going to work in the future only when the _old_ version is
> 9.2+.  Specifically, pg_upgrade using the flag could be patched to just
> 9.2, but the flag has to be supported on old and new backends for that
> to work.

OK, I started working on #3, which was to start the servers to find the
data_directory setting, and developed the attached patch which mostly
does this.  However, I have found serious problems with pg_ctl -w/wait
mode and config-only directories (which pg_upgrade uses), and will start
a new thread to address this issue and then continue with this once that
is resolved.

-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +