Problem: get_socket_address and get_socket_name not available throughout libzmq and restricted to local address

Solution: move to address.hpp/.cpp and generalize

Solution: add monitor event socket option

Solution: change to refer to the context

Solution: if a multi-part message cannot be delivered by a PUSH socket
because the pipe is broken mid-way, drop the rest of the frames so that
the atomicity property is not broken.

Solution: When pipe_t is freed (terminated) remove it from _endpoints member of zmq::socket_base_t. Resolves issue #3245.

Solution: define and use named constant

Solution: use terms more consistently

Solution: extract resolve_tcp_addr function

Solution: extract into functions of new inprocs_t class

Solution: replace by functional expression

Solution: extract functionality into send_routing_id

Solution: extract functionality into get_effective_conflate_option

Solution: remove them

Some code style improvements: removed redundant parentheses, added const, joined declaration and assignment of local variables

Solution: Add an identifier parameter for local attach to zmq::socket_base_t::attach_pipe

Solution: harmonize

Solution: introduced named constants

Problem: code style issues in options_t (C-style cast, suboptimal std::string::find call, redundant method is_valid)

Solution: resolved these issues

Solution: pull up functionality to base class

Solution: pulled up to routing_socket_base_t

Solution: pull up into routing_socket_base_t

Solution: add an intermediary base class routing_socket_base_t, move common functionality there and make connect_routing_id private

Solution: calculate from field sizes

Problem: inconsistent naming style for private data members, conflicts with naming of local variables and member functions

Solution: apply and check _lower_case naming style for private data members

Solution: simplify to comparison against 0

Solution: define and apply parameter naming style: lower_case_

Solution: replace by C++-style casts

Solution: make proper boolean expression

Solution: do it explicitly to fix build on Solaris 10/11 with the Sun
compiler

Solution: Add IPv6 support

Solution: do not call getsockopt to query thread-safety of a socket

Solution: commit clang-format-diff

* Problem: Still need to port over more files to VxWorks 6.x

Solution: Port more files to VxWorks 6.x

* Problem: Need to port over remaining files to VxWorks 6.x. Also remove POSIX thread dependency for VxWorks (because of priority inversion problem in POSIX mutexes with VxWorks 6.x processes)

Solution: Port over remaining files to VxWorks 6.x. Also removed POSIX thread dependency for VxWorks

* Problem: Needed to modify TCP, UDP, TIPC classes with #ifdefs to be compatible with VxWorks 6.x.

Solution:  Modify TCP, UDP, TIPC classes with #ifdefs to be compatible with VxWorks 6.x

* Tests for different TIPC address types and code cleanup

* Adds tests for binding/connecting with different TIPC address types
  using Unity
* Adds error checking for address type misuse

Solution: extracted common code into do_getsockopt/do_setsockopt functions

Solution: run make clang-format-diff and commit the changes.

The zero copy decoding strategy implemented for 4.2.0 can lead to a large
increase of main memory usage in some cases (I have seen one program go up to
40G from 10G after upgrading from 4.1.4). This commit adds a new option to
contexts, called ZMQ_ZERO_COPY_RECV, which allows one to switch to the old
decoding strategy.