Re: pg_recvlogical: Prevent flushed data from being re-sent after restarting replication

Hi Fujii,

This approach may be somewhat unstable. If there's a more robust
way to terminate pg_recvlogical on Windows, I'd be happy to switch
to it, but I couldn't come up with a better option.

Thanks for the updated patch set!

I applied them and it builds correctly and the test passes on my laptop.

About termination on Windows, I've noticed the following in file 006_logical_decoding.pl: 

# some Windows Perls at least don't like IPC::Run's start/kill_kill regime.
skip "Test fails on Windows perl", 2 if $Config{osname} eq 'MSWin32'; 

It seems that previously, in a similar situation the decision was to skip it on Windows. 

If we adopt the same approach for this test it should be fine, the production code in the patch is not Windows-specific.

Alternatively if we keep the approach in v4, we can consider updating 006_logical_decoding.pl as well so they're consistent. 

What do you think? 

-- 
Thanks,
Mircea Cadariu