epoll is a I/O event loop available on several *nix systems. Some third-party libraries to access it in Python have been available around the web, but I think it would be great to have it in stdlib.

Furthermore, it'll be available for using it in _socketmodule in place of poll, if there is an interest.

Attached a simple C version, and tests mostly extracted from twisted (where we use a pyrex version).

If it seems to be useful, I'd be glad to make the documentation.