At least on OS X 10.10 "Yosemite", an EPROTOTYPE can occur
when trying to write to a socket that is shutting down.
By retrying the write after EPROTOTYPE, we correctly get EPIPE.
PR-URL: https://github.com/libuv/libuv/pull/482
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>