rosserial spinOnce() blocks if not connected to ROS

edit

Using rosserial with an Arduino, I find that spinOnce() blocks if not connected to ROS, which makes sense (since how can you locally know when to go), so I am wondering if the standard call (for nodeHandle nh) inside the loop() should be:

if (nh.connected()) nh.spinOnce();
else {  ....deal with having disconnected from ROS and make the robot safe....then wait for reconnection....}

I saw on the logging page: http://www.ros.org/wiki/rosserial/Overview/Logging

//wait until you are actually connected
while (!nh.connected() ){
    nh.spinOnce();
}

but from what I am seeing with the arduino, you would get the same result with

nh.spinOnce();

alone, since it blocks. Is that correct?

Once ROS has disconnected, is there some way to put the arduino in a state where it can accept a reconnect cleanly?

Thanks again for all your help with this.