Thread: pgsql: On Windows, also call shutdown() while closing the client socket

On Windows, also call shutdown() while closing the client socket.

Further experimentation shows that commit 6051857fc is not sufficient
when using (some versions of?) OpenSSL.  The reason is obscure, but
calling shutdown(socket, SD_SEND) improves matters.

Per testing by Andrew Dunstan and Alexander Lakhin.
Back-patch as before.

Discussion: https://postgr.es/m/af5e0bf3-6a61-bb97-6cba-061ddf22ff6b@dunslane.net

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a9e572c6d5761e8f9b726ba2b9d63a01186994f1

Modified Files
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src/backend/libpq/pqcomm.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)