Re: PQputCopyEnd doesn't adhere to its API contract

From: Robert Haas <robertmhaas(at)gmail(dot)com>
To: Bruce Momjian <bruce(at)momjian(dot)us>
Cc: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: PQputCopyEnd doesn't adhere to its API contract
Date: 2014-09-04 16:59:41
Message-ID: CA+TgmoaM-nfBPbDSiQMjg3xocJXf7qZ539K50CbxLZFS5xupPQ@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Thu, Sep 4, 2014 at 12:53 PM, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> On Thu, Sep 4, 2014 at 12:52:14PM -0400, Robert Haas wrote:
>> On Wed, Sep 3, 2014 at 6:24 PM, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
>> > On Fri, May 9, 2014 at 12:03:36PM -0400, Robert Haas wrote:
>> >> On Thu, May 8, 2014 at 5:21 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> >> > Perhaps the text should be like this:
>> >> >
>> >> > The result is 1 if the termination message was sent; or in nonblocking
>> >> > mode, this may only indicate that the termination message was successfully
>> >> > queued. (In nonblocking mode, to be certain that the data has been sent,
>> >> > you should next wait for write-ready and call <function>PQflush</>,
>> >> > repeating until it returns zero.) Zero indicates that the function could
>> >> > not queue the termination message because of full buffers; this will only
>> >> > happen in nonblocking mode. (In this case, wait for write-ready and try
>> >> > the PQputCopyEnd call again.) If a hard error occurs, -1 is returned; you
>> >> > can use <function>PQerrorMessage</function> to retrieve details.
>> >>
>> >> That looks pretty good. However, I'm realizing this isn't the only
>> >> place where we probably need to clarify the language. Just to take
>> >> one example near at hand, PQputCopyData may also return 1 when it's
>> >> only queued the data; it seems to try even less hard than PQputCopyEnd
>> >> to ensure that the data is actually sent.
>> >
>> > Uh, where are we on this?
>>
>> I think someone needs to take Tom's proposed language and make it into
>> a patch. And figure out which other functions in the documentation
>> need similar updates.
>
> OK, did David G Johnston email comments from today help here?

I didn't look at them in detail, but they don't seem to match the
style of our documentation generally.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Robert Haas 2014-09-04 17:01:03 Re: postgresql latency & bgwriter not doing its job
Previous Message Bruce Momjian 2014-09-04 16:53:19 Re: PQputCopyEnd doesn't adhere to its API contract