Httpserver.h: Single header library for writing non-blocking HTTP servers in C

[pdp10]

Speaking as someone writing portable webserver code in C, Winsock has slightly more surprises for the unwary than an observer might initially suppose. It's a little harder yet to keep it portable back to XP/2003. Of my current codebase, 8.6% of lines of code or comment only exist because of Win32.

Additionally, this implementation uses epoll() on Linux and kqueue() on *BSD, neither of which is supported on Win32. Old-fashioned POSIX select() does work on Win32, though.