Workaround the broken select() in some Linux kernels that fails to report
a writable state on a socket when an error condition (or remote close) is
present.  Would be good to add actual test suite tests for this, but until
then see demo scripts in the ticket 1758a0b603.
Additional check for an error condition on the socket.
merge 8.5
[1758a0b603] socket-2.13 : Workaround the broken select() in some Linux
kernels that fails to report a writable state on a socket when an error
condition (or remote close) is present.
[1758a0b603] socket_*-2.13 : Workaround the broken select() in some Linux
kernels that fails to report a writable state on a socket when an error
condition (or remote close) is present.