From: Tom Lane <tgl@sss.pgh.pa.us>
To: Justin Pryzby <pryzby@telsasoft.com>
Cc: pgsql-hackers@postgresql.org, Fabien COELHO <coelho@cri.ensmp.fr>
Cc: Alvaro Herrera <alvherre@2ndquadrant.com>
Cc: David Steele <david@pgmasters.net>
Cc: Bossart, Nathan <bossartn@amazon.com>
Cc: Thomas Munro <thomas.munro@gmail.com>
Subject: Re: pg11+: pg_ls_*dir LIMIT 1: temporary files .. not closed at end-of-transaction
Date: Sun, 29 Mar 2020 13:22:04 -0400
Message-ID: <29512.1585502524@sss.pgh.pa.us> (raw)
In-Reply-To: <20200329171415.GL20103@telsasoft.com>
References: <20200311111921.GQ29065@telsasoft.com>
<21724.1583955158@sss.pgh.pa.us>
<20200312121156.GB29065@telsasoft.com>
<20200316155306.GM26184@telsasoft.com>
<3061.1584409130@sss.pgh.pa.us>
<20200317020017.GT26184@telsasoft.com>
<24244.1585415634@sss.pgh.pa.us>
<20200328183904.GI20103@telsasoft.com>
<28906.1585422475@sss.pgh.pa.us>
<27064.1585499825@sss.pgh.pa.us>
<20200329171415.GL20103@telsasoft.com>
Justin Pryzby <pryzby@telsasoft.com> writes:
> On Sun, Mar 29, 2020 at 12:37:05PM -0400, Tom Lane wrote:
>> After looking at the callers of pg_ls_dir_files, and noticing that
>> it's already defined to ignore anything that's not a regular file,
>> I think switching to lstat makes sense.
> Yea, only pg_ls_dir() shows special file types (and currently the others even
> hide dirs).
> The essence of your patch is to ignore ENOENT, but you also changed to use
> lstat(), which seems unrelated. That means we'll now hide (non-broken)
> symlinks. Is that intentional/needed ?
Well, the following comment says "ignore anything but regular files",
so I'm supposing that that is the behavior that we actually want here
and failed to implement correctly. There might be scope for
additional directory-reading functions, but I'd think you'd want
more information (such as the file type) returned from anything
that doesn't act this way.
In practice, since these directories shouldn't contain symlinks,
it's likely moot. The only place in PG data directories where
we actually expect symlinks is pg_tablespace ... and that contains
symlinks to directories, so that this function would ignore them
anyway.
regards, tom lane
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-hackers@postgresql.org
Cc: tgl@sss.pgh.pa.us, pryzby@telsasoft.com, coelho@cri.ensmp.fr, alvherre@2ndquadrant.com, david@pgmasters.net, bossartn@amazon.com, thomas.munro@gmail.com
Subject: Re: pg11+: pg_ls_*dir LIMIT 1: temporary files .. not closed at end-of-transaction
In-Reply-To: <29512.1585502524@sss.pgh.pa.us>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox