Re: A couple of cosmetic changes around shared memory code

On Mon, Jun 27, 2016 at 11:40 PM, Michael Paquier
<michael(dot)paquier(at)gmail(dot)com> wrote:
> On Tue, Jun 28, 2016 at 6:49 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> On Sun, Jun 26, 2016 at 6:19 AM, Piotr Stefaniak
>> <postgres(at)piotr-stefaniak(dot)me> wrote:
>>>> while investigating the shm_mq code and its testing module I made some
>>>> cosmetic improvements there. You can see them in the attached diff file.
>>>
>>> Revised patch attached.
>>
>> The first hunk of this corrects an outdated comment, so we should
>> certainly apply that. I'm not seeing what the value of the other bits
>> is.
>
> - proc_exit(1);
> + proc_exit(0);
> Looking again at this thread with fresh eyes, isn't the origin of the
> confusion the fact that we do need to have a non-zero error code so as
> the worker is never restarted thanks to BGW_NEVER_RESTART? Even with
> that, it is a strange concept to leave with proc_exit(1) in the case
> where a worker left correctly..

This code predates be7558162acc5578d0b2cf0c8d4c76b6076ce352, prior to
which proc_exit(0) forced an immediate, unconditional restart. It's
true that, given that commit, changing this code to do proc_exit(0)
instead of proc_exit(1) would be harmless. However, people writing
background workers that might need to work with 9.3 would be best
advised to stick with proc_exit(1). Therefore, I maintain that this
is not broken and doesn't need to be fixed.

--
Robert Haas
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