After speaking with Ben Gray and the discussion on the mailing list, this is an attempt to create a sockopt to allow connecting pipes to not immediately be available for traffic. The problem is in a PUSH to many PULL situation, where there is a connect to a PULL which is not there. This connect will immediately create a pipe (unlike bind), and traffic will be load balanced to that pipe. This means if there is a persistently unavailable end point then the traffic will queue until HWM is hit, and older messages will be lost.

This patch adds a sockopt ZMQ_DELAY_ATTACH_ON_CONNECT, which if set to 1 will attempt to preempt this behavior. It does this by extending the use of the session_base to include in the outbound as well as the inbound pipe, and only associates the pipe with the socket once it receives the connected callback via a process_attach message. This works, and a test has been added to show so, but may introduce unexpected complications. The shutdown logic in this class has become marginally more awkward because of this, requiring the session to serve as the sink for both pipes if shutdown occurs with a still-connecting pipe in place. It is also possible there could be issues around flushing the messages, but as I could not directly think how to create such an issue I have not written any code with regards to that.

The documentation has been updated to reflect the change, but please do check over the code and test and review.

it works but rises very serious questions.

Please add license header by your choice.
This file for 99% resemble crossroads-io/tests/shutdown.cpp

This allows us to actually report an error to the caller on resolve
failure, rather than asserting later on in the io thread.
Signed-off-by: Staffan Gimåker <staffan@spotify.com>

Signed-off-by: Philip Kovacs <phil@philkovacs.com>

The new function allows to retrieve options (flags)
from zmq_msg_t.
Signed-off-by: Chuck Remes <cremes@mac.com>
Renamed from zmq_msg_flags to zmq_getmsgopt
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Mikko Koppanen <mkoppanen@php.net>
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

So far the requests in req/rep pattern were delivered to and processed
by worker even though the original requester was dead. Thus,
the worker processing replies with noone to deliver results to.
This optimisation drops requests in two situations:

1. Queued inbound requests in XREP socket when peer disconnects.
2. Queued outbound requests in XREQ when socket is closed.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

This patch introduces two changes:
1. 32-bit ID is used to identify the peer instead of UUID
2. REQ socket seeds the label stack with unique 32-bit request ID
   It also drops any replies with non-matching request ID
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

- Add doc and tests
- Add options and setup
- Wait using poll/select
Signed-off-by: Fabien Ninoles <fabien@tzone.org>
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Mikko Koppanen <mkoppanen@php.net>

Signed-off-by: Mikko Koppanen <mkoppanen@php.net>

MinGW32 defines __int64_t as long long, which causes the build to fail
unless -Wno-long-long is used. In addition the shutdown_stress test
isn't currently compatible with Win.
Signed-off-by: Mikko Koppanen <mkoppanen@php.net>

The test suite uses the standard automake support. Tests are always built,
but run only when you do a "make check".