Re: What is the best and easiest implementation to reliably wait for the completion of startup?

"MauMau" <maumau307@gmail.com> writes:
> The bad thing is that pg_ctl continues to wait until the specified duration 
> passes, even if postgres fails to start. For example, it is naturally 
> desirable for pg_ctl to terminate when postgresql.conf contains a syntax 
> error.

Hmm, I thought we'd fixed this in the last go-round of pg_ctl wait
revisions, but testing proves it does not work desirably in HEAD:
not only does pg_ctl wait till its timeout elapses, but it then reports
"server started" even though the server didn't start.  That's clearly a
bug :-(

I think your proposal of a pipe-based solution might be overkill though.
Seems like it would be sufficient for pg_ctl to give up if it doesn't
see the postmaster.pid file present within a couple of seconds of
postmaster startup.  I don't really want to add logic to the postmaster
to have the sort of reporting protocol you propose, because not
everybody uses pg_ctl to start the postmaster.  In any case, we need a
fix in 9.1 ...
        regards, tom lane