public static extern int uv_async_send(UvAsyncHandle handle);
 public void async_send(UvAsyncHandle handle)
 {
     ThrowIfErrored(_uv_async_send(handle));
 }
 public static extern int uv_async_init(UvLoopHandle loop,UvAsyncHandle handle,uv_async_cb cb);
 public void async_init(UvLoopHandle loop, UvAsyncHandle handle, uv_async_cb cb)
 {
     loop.Validate();
     handle.Validate();
     ThrowIfErrored(_uv_async_init(loop, handle, cb));
 }