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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Greg Stark <stark@mit.edu>, Yurii Rashkovskii <yrashk@gmail.com>,
        Andrew Dunstan <andrew@dunslane.net>,
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Subject: Re: [PATCH] Allow Postgres to pick an unused port to listen
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
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Robert Haas <robertmhaas@gmail.com> writes:
> On Wed, Apr 12, 2023 at 1:31 PM Greg Stark <stark@mit.edu> wrote:
>> I don't object to using the pid file as the mechanism -- but it is a
>> bit of an awkward UI for shell scripting. I imagine it would be handy
>> if pg_ctl had an option to just print the port number so you could get
>> it with a simple port=`pg_ctl -D <dir> status-port`

> That's not a bad idea, and would provide some additional isolation to
> reduce direct dependency on the PID file format.

Yeah.  My main concern here is with limiting our ability to change
the pidfile format in future.  If we can keep the dependencies on that
localized to code we control, it'd be much better.

			regards, tom lane