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_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/ea5ecdadf6eacdc1ef5c67648ebaed2efcb0d07a

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