#if __linux__
LPOLLMSG = POLLMSG,
LPOLLRDHUP = POLLRDHUP,
-#elif __FreeBSD__
+#elif defined(__FreeBSD__)
LPOLLMSG = 0,
LPOLLRDHUP = 0,
+#else
+#error "Please add support for your OS."
#endif /* __linux__ */
LPOLLERR = POLLERR,
LPOLLHUP = POLLHUP | POLLNVAL,