Another goal was to keep the interface simple enough that it could be easily understood, and also possible to convert poll() or select() based applications to the new API with a minimum of changes. It was recognized that if the new interface was radically different, then it would essentially preclude modification of legacy applications which might otherwise take advantage of the new API. Expanding the amount information returned to the ap- plication to more than just the fact that an event occurred was also considered desirable. For readable sockets, the user may want to know how many bytes are actually pending in the socket buffer in order to avoid multiple read() calls
