public IOWatcher(IntPtr fd, EventTypes types, Loop loop, IOWatcherCallback callback)
: base(loop)
{
this.fd = fd;
this.callback = callback;
unmanaged_watcher = new UnmanagedIOWatcher ();
unmanaged_watcher.fd = fd.ToInt32 ();
unmanaged_watcher.events = types | EventTypes.EV__IOFDSET;
unmanaged_watcher.callback = CallbackFunctionPtr;
InitializeUnmanagedWatcher (unmanaged_watcher);
}