Sockets may now be migrated between OS threads; sockets may not be used by
more than one thread at any time. To migrate a socket to another thread the
caller must ensure that a full memory barrier is called before using the
socket from the target thread.
The new zmq_close() semantics implement the behaviour discussed at:
http://lists.zeromq.org/pipermail/zeromq-dev/2010-July/004244.html
Specifically, zmq_close() is now deterministic and while it still returns
immediately, it does not discard any data that may still be queued for
sending. Further, zmq_term() will now block until all outstanding data has
been sent.
TODO: Many bugs have been introduced, needs testing. Further, SO_LINGER or
an equivalent mechanism (possibly a configurable timeout to zmq_term())
needs to be implemented.
definitions as aliases, to be removed in release 3.0. Also renamed the source
files implementing these two socket types. This change does not break existing
applications nor bindings, but allows us to fix the documentation and user guide
now, rather than keeping the old (confusing) names.
