From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alexander Law <exclusion@gmail.com>
cc: Amit Kapila <amit.kapila16@gmail.com>,
        PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>
Subject: Re: BUG #16154: pg_ctl restart with a logfile fails sometimes (on
 Windows)
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References: <16154-1ccf0b537b24d5e0@postgresql.org>
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Comments: In-reply-to Alexander Law <exclusion@gmail.com>
	message dated "Sat, 07 Dec 2019 19:00:01 +0300"
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Date: Sat, 07 Dec 2019 11:54:54 -0500
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Alexander Law <exclusion@gmail.com> writes:
> What is the reason for the previous shell still accessing logfile?
> Is the reason that we don't close it before unlinking the pid file?

> We can't close the logfile, as it is opened by CMD, not by the postgres
> process. (Postmaster is started by the command "CMD.EXE /C postgres ...
>> logfile".) So it is closed by the CMD shell after the postgres process
> exits and the postgres can't control this (as a child process).

Hmm ... so if we were talking about Unix, a reasonable solution would
be to avoid having a separate shell process, either by telling the shell
to "exec" the postmaster or by using fork/exec directly with no shell.
A 99% solution would be to use "&" so that the shell doesn't wait around
for the postmaster to die.

Are any of those ideas tenable on Windows?

			regards, tom lane