Depending on the windows target version (_WIN32_WINNT), the used
SDK and the build configuration the linker will see multiple
libraries exporting the same symbols.
To prevent ugly hacks (e.g. modifying cmake's default system
libraries or fragile library linking order chains) we prefix
these functions with "winpr_" and create corresponding defines
to keep the current api names.
winsock.h pulls in a lot of defines and dependencies that are not
required and partially unwanted in winpr's core (for parts that are not
related to network). In order to get rid of this dependency and have an
independent defines for extended winpr functions the WINPR_FD_* defines
are used internally (and for exposed functions). Where required, like in
WSAEventSelect, the FD_* is mapped to WINPR_FD_*.
WSAEventSelect did ignore the lNetworkEvents argument.
In case this argument is 0, the non blocking socket must
be set to blocking again to mimic windows behavior.
select() has the major drawback that it cannot handle file descriptor
that are bigger than 1024. This patch makes use of poll() instead of
select() when poll() support is available.
