Re: Does recovery write to backup_label ?

On 2/7/20 2:55 PM, Andres Freund wrote:

>> If the file needs to have 0600 permissions, should there be
>> a note in the nonexclusive-mode backup docs to say so?
>
> I'm not convinced that that's useful. The default is that everything
> needs to be writable by postgres. The exceptions should be noted if
> anything, not the default.

Could this arguably be a special case, as most things in the datadir
are put there by postgres, but the backup_label is now to be put there
(and not even 'there' there, but added as a final step only to a
'backup-copy-of-there' there) by the poor schmuck who reads the
non-exclusive backup docs as saying "retrieve this content from
pg_stop_backup() and preserve in a file named backup_label" and can't
think of any obvious reason to put write permission on a file
that preserves immutable history in a backup?

Regards,
-Chap