public static extern int zoo_awexists(IntPtr zh, string path, watcher_fn watcher, IntPtr watcherCtx, stat_completion_t completion, IntPtr data);
public static extern int zoo_aset(IntPtr zh, string path, string buffer, int buflen, int version, stat_completion_t completion, IntPtr data);
public static extern int zoo_aexists(IntPtr zh, string path, int watch, stat_completion_t completion, IntPtr data);