Solution: modify order of operations, add diagnostic output

Solution: add initial implementation

Solution: added call

Solution: extract as_socket_base_t function

Solution: added test case (with dummy implementation of zmq_socket_get_peer_state)

Solution: extracted test_basic function

Problems: ZMQ_HAVE_O_CLOEXEC not defined by CMake, support for CMake << 3.1 broken

Solution: remove redundant target_sources directive

Solution: add it to CMake's platform.hpp.in

Problem: ZMQ_HAVE_O_CLOEXEC always disabled

Solution: Escape quotes in cmake test.

Problem: Inconsistent size_t/int usage. size_t and int don't match in 64 bit build and produce warnings. Solution: types corrected.

Problem: cosmetic setThreadName() can be fatal

Solution: do not assert() the values returned; if we failed to set the thread name - we just have harder debugging, not flawed production conditions.
Closes github issue #2679
Signed-off-by: Jim Klimov <EvgenyKlimov@eaton.com>

Problem: bug reports are often missing relevant information

Solution: provide template for bug reports

Problem: coverage includes tweetnacl, which is not our code

Solution: exclude tweetnacl from coverage

Problem: insufficient tests for zmq_timers_* and inadequate behaviour in corner cases

Solution: add test

Problem: missing tests for zmq_timers_* corner cases, missing handling of such corner cases, code duplication, missing assertions in test code

Solution: add tests, add checks to timers_t, add match_by_id functor, add assertions

Solution: added tests

Solution: replace sleep_ my msleep

Problem: insufficient tests for zmq_poller_*

Problem: replaced by assertions resp. removed

Solution: added test cases

Solution: add test case

Solution: replace ETIMEDOUT within socket_poller_t and all client code by EAGAIN

Fixes #2713

Solution: Return EBADF instead

Problem: calling zmq_poller_wait* with NULL events causes an assertion, as opposed to other NULL arguments, which return an error

Solution: return EFAULT when such an operation is attempted

Solution: return EFAULT when such an operation is attempted

Problem: missing test cases for zmq_poller_* functions called with invalid arguments and corner cases for zmq_poller_wait_*

Solution: added test cases

Solution: add checks, added test cases

Solution: added test cases

Problem: no tests for socket-related functions passing NULL as socket

Soluton: added tests

Problem: code duplication within zmq::select_t::rm_fd

Solution: extract find_fd_entry_by_handle from rm_fd

Problem: packages builds not mentioned in README.md