From: Tom Lane <tgl@sss.pgh.pa.us>
To: Magnus Hagander <magnus@hagander.net>
cc: Christian Ullrich <chris@chrullrich.net>,
        pgsql-admin <pgsql-admin@postgresql.org>
Subject: Re: Why does the WAL writer sit on completed segments (on Windows)?
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Comments: In-reply-to Magnus Hagander <magnus@hagander.net>
	message dated "Mon, 17 Apr 2017 18:38:39 +0200"
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Date: Mon, 17 Apr 2017 12:55:52 -0400
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Magnus Hagander <magnus@hagander.net> writes:
> But all our files are opened with (FILE_SHARE_READ | FILE_SHARE_WRITE |
> FILE_SHARE_DELETE). So shouldn't this allow 7zip (or whatever) to open up
> the file, regardless of us holding it open? (Looking at
> https://msdn.microsoft.com/en-us/library/windows/desktop/aa363874(v=3Dvs.=
85).aspx
> at least that's how I read it?)

My understanding of what Christian wrote is that 7zip is using flags
that specifically disallow "sharing".  The flags we use will allow other
programs to open the file(s) with default options, but a program that
is deliberately trying to be the sole user of the file can still notice
our opens.

			regards, tom lane


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