Update signaler make_fdpair to set file descriptors to -1 when too many files are open using socketpair.

Fix socket creation above sistem limits for all 'other' OS not covered by eventfd, windows or vms; enhanced test to create sockets up to a bigger limit to really test hitting the OS limit

By default, TIPC uses a closest first approach to find
a publication that can satisfy your connection request.
Any publication on the local node will automatically
be chosen for all requests, even if you're trying to
spread it out over multiple machines.
We fix this by widening the default lookup scope.
Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>

As TIPC transport for 0MQ will only work on post 3.8
Linux kernels where nonblocking connect was added,
we add AC_RUN test to check for this functionality.
Should the test fail, tipc is excluded from build/test.
Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>

A ZeroMQ application can opt for TIPC based sockets
using the TIPC port name format:
zmq_bind(sb, "tipc://{type,lower,upper}");
zmq_connect(sc, "tipc://{type,inst}");

'type' is the service ID, and 'lower/upper' can be
used for service partitioning or basic load
balancing.

ZeroMQ TIPC transport requires a kernel >= 3.8
(nonblocking connect support for TIPC).
Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>

Shorten ZMQ_ROUTER_REASSIGN_IDENTITIES to ZMQ_ROUTER_HANDOVER. Also, added a test for the HANDOVER functionality.

Crash Fix: Assertion failed: Permission denied (..\..\..\src\tcp_connecter.cpp:279) on windows 8

* The ZMQ_ROUTER_RAW API was deprecated in favor of ZMQ_STREAM
* Same issue hit router.cpp, which I've fixed

- removed unnecessary malloc
- spaces, not tabs to indent
- renamed control states to be more logical
- renamed SUSPEND to PAUSE, feels more accurate
- fixed indentation, which was off in places

https://zeromq.jira.com/browse/LIBZMQ-565

Abstract socket pathnames must have a NULL character in the first
position, but the second character must also be checked to differentiate
an abstract name from the empty string.  The address length must also
indicate the length of the pathname because the kernel uses the entire
address as the name, including NULL characters.  ZMQ uses
NULL-terminated strings for the address, so the abstract address length
is the length of the string following the initial NULL byte plus 3; two
bytes for the address family and one for the initial NULL character.

Converts an initial strudel or "at sign" (@) in the Unix socket path to
a NULL character ('\0') indicating that the socket uses the abstract
namespace instead of the filesystem namespace.  For instance, binding a
socket to 'ipc://@/tmp/tester' will not create a file associated with
the socket whereas binding to 'ipc:///tmp/tester' will create the file
/tmp/tester.  See issue 567 for more information.

asserts aren't appropriate for checking user input.

* Tests dealer-to-router connection 100 times
* This was failing in ZMQ v4.0.0 RC1

* The INITIATE command vouch box is Box[C',S](C->S') instead of Box[C'](C->S),
  as recommended by https://codesinchaos.wordpress.com/2012/09/09/curvecp-1/,
  to reduce the risk of client impersonation.

* Mirrors the change in libcurve and CurveZMQ specifications.