Problem: API poller cannot be set independently from I/O thread poller, poll I/O thread poller broken on Windows

Solution: change platform definitions to separate API poller from I/O thread poller, disallow configuring poll I/O thread poller on Windows

Solution: added test case, reproduces the likely cause for #3107

Fix some more code style issues

Solution: replace by C++-style casts

Solution: add no-return attributes

Solution: add alloc_assert calls

Solution: replace by for loop

Solution: restructured code, inverted condition

Solution: properly declared underlying type of enum declaring retired_fd

Solution: fix #if/#else structure

Solution: change options_t.type to int8_t

Fix some code style issues

Solution: remove redundant else

Solution: reduce to newly extracted function clear, which does not use the freed pointer

Solution: add code to make non-use explicit

Solution: call check_read instead

Solution: add explicit

Fixed compilation with ZMQ_ATOMIC_PTR_MUTEX

Reenable DRAFT builds on Appveyor and fix test_radio_dish_udp_ipv6

Solution: fix handling of sockaddr in recvfrom

Solution: fix types

Solution: set ENABLE_DRAFTS=ON

Problem: test_spec_dealer not using test framework

Solution: migrate to Unity

Warnings in Windows builds

Solution: handle types properly

Solution: Use fd_t

Solution: Use size_t instead of int

Solution: Use unsigned char instead of size_t

Solution: Use unsigned char instead of size_t

Solution: Use fd_t

Solution: Use fd_t

Solution: explicitly compare function pointer against NULL

Solution: make proper boolean expression

Solution: make proper boolean expression

Solution: move conditional include directive to precompiled.hpp

Solution: fix type specification

Solution: fix type specification