title: RabbitMQ PHP AMQP Library - Get message headers
body: <p>I have got a simple queueing system which, obviously, takes messages and publishes them.</p>
  
  <p>However, due to a new development in the system, we now need to check for the <code>x-death</code> headers from the exchange, however, I can't seem any documentation on how to retrieve that through the PHP AMQP Library.</p>
  
  <p>Anyone have any ideas on how to achieve this?</p>