libpq changes for synchronous replication

On Fri, Sep 17, 2010 at 5:09 PM, Heikki Linnakangas
<heikki(dot)linnakangas(at)enterprisedb(dot)com> wrote:
> That said, there's a few small things that can be progressed regardless of
> the details of synchronous replication. There's the changes to trigger
> failover with a signal, and it seems that we'll need some libpq changes to
> allow acknowledgments to be sent back to the master regardless of the rest
> of the design. We can discuss those in separate threads in parallel.

Agreed. The attached patch introduces new function which is used
to send ACK back from walreceiver. The function sends a message
to XLOG stream by calling PQputCopyData. Also I allowed PQputCopyData
to be called even during COPY OUT.

Regards,

--
Fujii Masao
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center