So far, the pipe termination code was spread among socket type
classes, fair queuer, load balancer, etc. This patch moves
all the associated logic to a single place.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>
Reaper thread destroys the socket asynchronously.
zmq_term() can be interrupted by a signal (EINTR).
zmq_socket() will return ETERM after zmq_term() was called.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>