libev is modelled after libevent (http://monkey.org/~provos/libevent/), but aims
to be faster and more correct, and also more featureful. Examples:

- multiple watchers can wait for the same event without deregistering others.
- fork() is supported and can be handled.
- timers are handled as a priority queue (faster)
- watchers use less memory (faster)
- less calls to epoll_ctl (faster)