This is important in order to send the login sequence of a client to the server.
Solution: add ZMQ_HICCUP_MSG to a socket, socket would send that message whenever a connection get temporarly disconnected
* Problem: No direct support for setting socket priority
Solution: Add ZMQ_PRIORITY socket option, which sets the
SO_PRIORITY socket option on the underlying socket. This
socket option is not supported under Windows. Check option
and set socket option on creation of underlying socket.
ZMQ_ROUTER_NOTIFY doesn't have a context and doesn't play nice with protocols. with ZMQ_DISCONNECT_MSG we can set it to a protocol message, like DISCONNECT in majordomo. Router will send it when a peer is disconnected. Another advantage of ZMQ_DISCONNECT_MSG is that it also works on inproc.
Together with ZMQ_HEARTBEAT it allows to build very reliable protocols, and much simpler as well.
When using ZMQ_HEARTBEAT one still needs to implement application-level heartbeat in order to know when to send a hello message.
For example, with the majordomo protocol, the worker needs to send a READY message when connecting to a broker. If the connection to the broker drops, and the heartbeat recognizes it the worker won't know about it and won't send the READY msg.
To solve that, the majordomo worker still has to implement heartbeat. With this new option, whenever the connection drops and reconnects the hello message will be sent, greatly simplify the majordomo protocol, as now READY and HEARTBEAT can be handled by zeromq.
Solution: a new socket type, called PEER. Very similar to SERVER, but can only connect to other PEERs. Also a new zmq_connect_peer method, that connect and return a routing-id in thread-safe and atomic operation
Solution: now if the first frame in a multipart message is not subscribe/unsubscribe,
the rest of the parts are also considered to be not subscribe/unsubscribe.
how it declares the file descriptor (fd) of a socket
in struct zmq_pollitem_t vs. struct zmq_poller_event_t
Solution: Make include/zmq.h consistent in this matter
* Add ZMQ_XPUB_MANUAL_LAST_VALUE
* Surpport xpub send last value caching to one pipe with ZMQ_XPUB_MANUAL_LAST_VALUE
* Add test_xpubub_manual_last_value
* Add relicense and doc
Solution: Allow ZMQ_PUB and ZMQ_PUSH sockets types for the monitoring.
This way someone could create a ZMQ_PULL socket connected to multiple
monitoring sockets at the same time.
Solution: add API and ZMQ_EVENT_PIPES_STATS event which generates 2
values, one for the egress and one for the ingress pipes respectively.
Refactor the events code to be able to send multiple values.
Solution: define uint64_t if not available in the system headers and
remove inclusion of inttypes.h which does not exist and is already
conditionally included in zmq.h if required, do not use PRIx64
