title: What happens when you call receive_message() on an empty SQS queue?
body: <p>I'm trying to count the number of times a PHP process calls receive_message() on an empty AWS SQS queue. Right now I have it working by counting every time MessageID is not set the queue is empty. Is there a more direct way of checking?</p>
  
  <p><a href="http://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs-queue-message-identifiers.html" rel="nofollow noreferrer">http://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs-queue-message-identifiers.html</a></p>
  
  <pre><code>if(!isset($sqsMessage-&gt;body-&gt;ReceiveMessageResult-&gt;Message-&gt;MessageId)) {
      //Log empty call here
  }
  </code></pre>