NEWS

    zmq_ctx_set() - set context property
    zmq_ctx_get() - get context property

* Fixed issue xxx - Cleaned-up message API:

    zmq_msg_send() - send a message (will deprecate zmq_sendmsg)
    zmq_msg_recv() - receive a message (will deprecate zmq_recvmsg)
    zmq_msg_more() - indicate whether this is final part of message
    zmq_msg_get() - get message property
    zmq_msg_set() - set message property

* Fixed issue xxx - Added context monitoring API:

    zmq_ctx_set_monitor() - configure monitor callback.

* Fixed issue xxx - Added unbind/disconnect API:

    zmq_unbind() - unbind socket.
    zmq_disconnect() - disconnect socket.

* Fixed issue xxx - Added ZMQ_TCP_ACCEPT_FILTER setsockopt() for listening TCP sockets.

* Fixed issue 336 - Removed sys: transport.

* Fixed issue 333 - Added zmq_device function back to API (was removed
  in 3.0).

* Fixed issue 340 - Add support for MAX_SOCKETS to new context API.


OMQ version 3.1.0 (beta), released on 2011/12/18
================================================

General information
-------------------

Based on community consensus, the 0MQ 3.1.x release reverts a number of
features introduced in version 3.0. The major reason for these changes is
improving backward compatibility with 0MQ 2.1.x.

Development of the 0MQ 3.0.x series will be discontinued, and users are
encouraged to upgrade to 3.1.

The 0MQ 3.1.x releases use ABI version 3.

Reverted functionality
----------------------

The following functionality present in 0MQ 3.0 has been reverted:

* Wire format changes. The 0MQ 3.1 wire format is identical to that of 0MQ
  2.1.

* LABELs and COMMANDs have been removed.

* Explicit identies are re-introduced, however they can be used only for
  explicit routing, not for durable sockets.

* The ZMQ_ROUTER and ZMQ_DEALER socket types are once again aliases for
  ZMQ_XREQ and ZMQ_XREP.

New functionality
-----------------

* The zmq_getmsgopt() function has been introduced.

* Experimental IPv6 support has been introduced. This is disabled by
  default, see the zmq_setsockopt() documentation for enabling it.

Other changes
-------------

* The default HWM for all socket types has been set to 1000.

* Many bug fixes.

Building
--------

* The dependency on libuuid has been removed.

* Support for building on Android, and with MSVC 10 has been added.

0MQ version 3.0.0 (alpha), released on 2011/07/12
=================================================

New functionality
-----------------

* A zmq_ctx_set_monitor() API to register a callback / event sink for changes
  in socket state.

* POSIX-compliant zmq_send and zmq_recv introduced (uses raw buffer
  instead of message object).

* ZMQ_MULTICAST_HOPS socket option added. Sets the appropriate field in
  IP headers of PGM packets.

* Subscription forwarding. Instead of filtering on consumer, the
  subscription is moved as far as possible towards the publisher and
  filtering is done there.

* ZMQ_XPUB, ZMQ_XSUB introduced. Allow to create subscription-
  forwarding-friendly intermediate devices.

* Add sockopt ZMQ_RCVTIMEO/ZMQ_SNDTIMEO. Allow to set timeout for
  blocking send/recv calls.

* A new LABEL flag was added to the wire format. The flag distinguishes
  message parts used by 0MQ (labels) from user payload message parts.

* There is a new wire format for the REQ/REP pattern. First, the empty
  bottom-of-the-stack message part is not needed any more, the LABEL
  flag is used instead. Secondly, peer IDs are 32-bit integers rather
  than 17-byte UUIDs.

* The REQ socket now drops duplicate replies.

* Outstanding requests & replies associated with a client are dropped
  when the clients dies. This is a performance optimisation.

* Introduced ZMQ_ROUTER and ZMQ_DEALER sockets. These mimic the
  functionality of ZMQ_ROUTER and ZMQ_DEALER in 0MQ/2.1.x. Guarantees
  backward compatibility for exsiting code.

* Removed dependency on OS socketpair buffer size. No more asserts in
  mailbox.cpp because of low system limit of sockepair buffer size.

API improvements
----------------

* Obsolete constants ZMQ_UPSTREAM and ZMQ_DOWNSTREAM removed. Use
  ZMQ_PUSH and ZMQ_PULL instead.

* Timeout in zmq_poll is in milliseconds instead of microseconds. This
  makes zmq_poll() compliant with POSIX poll()

* ZMQ_MCAST_LOOP removed. There's no support for multicast over
  loopback any more. Use IPC or TCP isntead.

* zmq_send/zmq_recv was renamed zmq_sendmsg/zmq_recvmsg.

* ZMQ_RECOVERY_IVL and ZMQ_RECOVERY_IVL_MSEC reconciled. The new option
  is named ZMQ_RECOVERY_IVL and the unit is milliseconds.

* Option types changed. Most of the numeric types are now represented
  as 'int'.

* ZMQ_HWM split into ZMQ_SNDHWM and ZMQ_RCVHWM. This makes it possible
  to control message flow separately for each direction.

* ZMQ_NOBLOCK renamed ZMQ_DONTWAIT. That makes it POSIX-compliant.

Less is More
------------

* Pre-built devices and zmq_device() removed. Should be made available
  as a separate project(s).

* ZMQ_SWAP removed. Writing data to disk should be done on top of 0MQ,
  on inside it.

* C++ binding removed from the core. Now it's a separate project, same
  as any other binding.

Bug fixes
---------

* Many.

Building
--------

* Make pkg-config dependency conditional.

Distribution
------------

* Removed Debian packaging, which is now available at packages.debian.org
  or via apt-get.


0MQ version 2.2.0 (Stable), released on 2012/04/04
==================================================

Changes
-------

* Fixed issue 349, add send/recv timeout socket options.

Bug fixes
---------

* Fixed issue 301, fix builds on HP-UX 11iv3 when using either gcc or aCC.

* Fixed issue 305, memory leakage when using dynamic subscriptions.

* Fixed issue 332, libzmq doesn't compile on Android NDK.

* Fixed issue 293, libzmq doesn't follow ZMTP/1.0 spec.

* Fixed issue 342, cannot build against zmq.hpp under C++11.


0MQ version 2.1.11 (Stable), released on 2011/12/18
===================================================

Bug fixes
---------

* Fixed issue 290, zmq_poll was using system time instead of monotonic
  clock (Mika Fischer).

* Fixed issue 281, crash on heavy socket creation - assertion failure in
  mutex.hpp:91. (Mika Fischer).

* Fixed issue 273, O_CLOEXEC flag used in ip.cpp:192 is supported only
  on Linux kernels 2.6.27+

* Fixed issue 261, assertion failure in kqueue.cpp:76.

* Fixed issue 269, faulty diagnostic code in 2.1.10.

* Fixed issue 254, assertion failure at tcp_socket.cpp:229 on ENOTCONN.

Changes
-------

* Now builds properly on AIX 6.1 (AJ Lewis).

* Builds using libdcekt on HP-UX (AJ Lewis).

* New upstream OpenPGM maintenance release 5.1.118.

* Enabled debugging on assertion failure on Windows (Paul Betts).


0MQ version 2.1.10 (Stable), released on 2011/10/03
===================================================

Bug fixes
---------

* Fixed issue 140, SWAP failed with assertion failure in pipe.cpp:187
  if the current directory was not writeable. Behavior now is to return
  -1 at zmq_setsockopt in this situation.

* Fixed issue 207, assertion failure in zmq_connecter.cpp:48, when an
  invalid zmq_connect() string was used, or the hostname could not be
  resolved. The zmq_connect() call now returns -1 in both those cases.

* Fixed issue 218, sockets not opened with SOCK_CLOEXEC, causing fork/exec
  to sit on sockets unnecessarily.

* Fixed issue 250, build errors on Windows (Mikko Koppanen).

* Fixed issue 252, assertion failure in req.cpp:87 and req.cpp:88 (Mikko
  Koppanen).


0MQ version 2.1.9 (Stable), released on 2011/08/29
==================================================

Bug fixes
---------

* Fixed issue 240, assertion failure in pgm_socket.cpp:437.

* Fixed issue 238, assertion failure in zmq.cpp:655, when zmq_poll is
  used on an empty set, on Windows.

* Fixed issue 239, assertion failure in zmq.cpp:223, when ZMQ_SWAP was
  used with explicit identities and multiple SUB sockets.

* Fixed issue 236, zmq_send() and zmq_recv() did not always return
  error conditions such as EFSM properly. This bug was introduced in
  version 2.1.8 by the backport of changes for issue 231.

Building
--------

* 0MQ support for Android added (Bill Roberts, Mikko Koppanen).


0MQ version 2.1.8 (RC), released on 2011/07/28
==============================================

Bug fixes
---------

* Fixed issue 223, assertion failure in tcp_connecter.cpp:300 when
  connecting to a server that is on an unreachable network (errno is
  equal to ENETUNREACH).

* Fixed issue 228, assertion failure at rep.cpp:88 when HWM was reached.

* Fixed issue 231, assertion failure at mailbox.cpp:183 when too many
  pending socketpair operations were queued (major backport from 3.0).

* Fixed issue 234, assertion failure at mailbox.cpp:77 when Ctrl-C was
  used (only affected git master following backport for 231).

* Fixed issue 230, SIGPIPE killing servers when client disconnected, hit
  OS/X only.

Note: this release was renamed "release candidate" due to issue 236,
fixed in 2.1.9.


0MQ version 2.1.7 (Stable), released on 2011/05/12
==================================================

Bug fixes
---------

* Fixed issue 188, assert when closing socket that had unread multipart
  data still on it (affected PULL, SUB, ROUTER, and DEALER sockets).

* Fixed issue 191, message atomicity issue with PUB sockets (an old issue).

* Fixed issue 199 (affected ROUTER/XREP sockets, an old issue).

* Fixed issue 206, assertion failure in zmq.cpp:223, affected all sockets
  (bug was introduced in 2.1.6 as part of message validity checking).

* Fixed issue 211, REP socket asserted if sent malformed envelope (old issue
  due to abuse of assertions for error checking).

* Fixed issue 212, reconnect failing after resume from sleep on Windows
  (due to not handling WSAENETDOWN).

* Properly handle WSAENETUNREACH on Windows (e.g. if client connects
  before server binds).

* Fixed memory leak with threads on Windows.

Changes
-------

* Checks zmq_msg_t validity at each operation.

* Inproc performance tests now work on Windows.

* PGM wire format specification improved in zmq_pgm(7)

* Added thread latency/throughput performance examples.

* Added "--with-system-pgm" configure option to use already installed
  OpenPGM.

* Runtime checking of socket and context validity, to catch e.g. using a
  socket after closing it, or passing an invalid pointer to context/socket
  methods.

* Test cases moved off port 5555, which conflicts with other services.

* Clarified zmq_poll man page that the resolution of the timeout is 1msec.


0MQ version 2.1.6 (Broken), released on 2011/04/26
==================================================

Note that this version contained a malformed patch and is not usable.
It is not available for download, but is available in the git via the
2.1.6 tag.

0MQ version 2.1.5 (Broken), released on 2011/04/20
==================================================

Note that this version contained a malformed patch and is not usable.
It is not available for download, but is available in the git via the
2.1.5 tag.


0MQ version 2.1.4 (Stable), released on 2011/03/30
==================================================

Bug fixes
---------

* Fix to OpenPGM which was asserting on small messages (Steven McCoy).

Changes
-------

* Upgraded OpenPGM to version 5.1.115 (Pieter Hintjens).

* OpenPGM build changed to not install OpenPGM artifacts.


0MQ version 2.1.3 (Stable), released on 2011/03/21
==================================================

Bug fixes
---------

* Fix to PUSH sockets, which would sometimes deliver tail frames of a
  multipart message to new subscribers (Martin Sustrik).

* Fix to PUB sockets, which would sometimes deliver tail frames of a
  multipart message to new subscribers (Martin Sustrik).

* Windows build was broken due to EPROTONOSUPPORT not being defined. This
  has now been fixed (Martin Sustrik).

* Various fixes to make OpenVMS port work (Brett Cameron).

* Corrected Reference Manual to note that ZMQ_LINGER socket option may be
  set at any time, not just before connecting/binding (Pieter Hintjens).

* Fix to C++ binding to properly close sockets (Guido Goldstein).

* Removed obsolete assert from pgm_socket.cpp (Martin Sustrik).

Changes
-------

* Removed stand-alone devices (/devices subdirectory) from distribution.
  These undocumented programs remain available in older packages (Pieter
  Hintjens).

* OpenPGM default rate raised to 40mbps by default (Steven McCoy).

* ZMQ_DEALER and ZMQ_ROUTER macros provided to ease upgrade to 0MQ/3.0.
  These are scheduled to replace ZMQ_XREQ and ZMQ_XREP (Pieter Hintjens).

* Added man page for zmq_device(3) which was hereto undocumented (Pieter
  Hintjens).

* Removed zmq_queue(3), zmq_forwarder(3), zmq_streamer(3) man pages
  (Pieter Hintjens).

OpenPGM Integration
-------------------

* Upgraded OpenPGM to version 5.1.114 (Steven McCoy, Mikko Koppanen).

* Build system now calls OpenPGM build process directly, allowing easier
  future upgrades of OpenPGM (Mikko Koppanen).

* Build system allows configuration with arbitrary versions of OpenPGM
  (./configure --with-pgm=libpgm-x.y.z) (Mikko Koppanen).

* OpenPGM uses new PGM_ODATA_MAX_RTE controlling original data instead of
  PGM_TXW_MAX_RTE covering entire channel (Steven McCoy).

Building
--------

* 0MQ builds properly on FreeBSD (Mikko Koppanen).


0MQ version 2.1.2 (rc2), released on 2011/03/06
===============================================

Bug fixes
---------

* 0MQ now correctly handles durable inproc sockets; previously it ignored
  explicit identities on inproc sockets.

* Various memory leaks were fixed.

* OpenPGM sender/receiver creation fixed.


0MQ version 2.1.1 (rc1), released on 2011/02/23
===============================================

New functionality
-----------------

* New socket option ZMQ_RECONNECT_IVL_MAX added, allows for exponential
  back-off strategy when reconnecting.

* New socket option ZMQ_RECOVERY_IVL_MSEC added, as a fine-grained
  counterpart to ZMQ_RECOVERY_IVL (for multicast transports).

* If memory is exhausted, 0MQ warns with an explicit message before
  aborting the process.

* Size of inproc HWM and SWAP is sum of peers' HWMs and SWAPs (Douglas
  Greager, Martin Sustrik).

Bug fixes
---------

* 0MQ no longer asserts in mailbox.cpp when multiple peers connect with
  the same identity.

* 0MQ no longer asserts when rejecting an oversized message.

* 0MQ no longer asserts in pipe.cpp when the swap fills up.

* zmq_poll now works correctly with an empty poll set.

* Many more.

Building
--------

* 0MQ now builds correctly on CentOS, Debian 6, and SunOS/gcc3.

* Added WithOpenPGM configuration into MSVC builds.

Known issues
------------

* OpenPGM integration is still not fully stable.


0MQ version 2.1.0 (Beta), released on 2010/12/01
================================================

New functionality
-----------------

* New semantics for zmq_close () and zmq_term () ensure that all messages
  are sent before the application terminates. This behaviour may be
  modified using the new ZMQ_LINGER socket option; for further details
  refer to the reference manual.

* The new socket options ZMQ_FD and ZMQ_EVENTS provide a way to integrate
  0MQ sockets into existing poll/event loops.

* Sockets may now be migrated between OS threads, as long as the
  application ensures that a full memory barrier is issued.

* The 0MQ ABI exported by libzmq.so has been formalised; DSO symbol
  visibility is used on supported platforms to ensure that only public ABI
  symbols are exported. The library ABI version has been set to 1.0.0 for
  this release.

* OpenPGM has been updated to version 5.0.92. This version no longer
  depends on GLIB, and integration with 0MQ should be much improved.

* zmq_poll() now honors timeouts precisely, and no longer returns if no
  events are signaled.

* Blocking calls now return EINTR if interrupted by the delivery of a
  signal; this also means that language bindings which previously had
  problems with handling SIGINT/^C should now work correctly.

* The ZMQ_TYPE socket option was added; this allows retrieval of the socket
  type after creation.

* Added a ZMQ_VERSION macro to zmq.h for compile-time API version
  detection.

* The ZMQ_RECONNECT_IVL and ZMQ_BACKLOG socket options have been added.

Bug fixes
---------

* Forwarder and streamer devices now handle multi-part messages correctly.

* 0MQ no longer asserts when malformed data is received on the wire.

* 0MQ internal timers now work correctly if the TSC jumps backwards.

* The internal signalling functionality (mailbox) has been improved
  to automatically resize socket buffers on POSIX systems.

* Many more.

Building
--------

* 0MQ now builds correctly with many more non-GCC compilers (Sun Studio,
  Intel ICC, CLang).

* AIX and HP-UX builds should work now.

* FD_SETSIZE has been set to 1024 by default for MSVC builds.

* Windows builds using GCC (MinGW) now work out of the box.

Distribution
------------

* A simple framework for regression tests has been added, along with a few
  basic self-tests. The tests can be run using "make check".