Most C99 + POSIX systems should be supported. Windows is not, since it does not
support Unix-style events, and (although this is a minor concern) it does not
support sendmsg and recvmsg.

In addition, since this program depends on libev, the portability requirements
of libev must be satisfied:
http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#PORTABILITY_NOTES