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diff --git a/src/rabbit_backing_queue.erl b/src/rabbit_backing_queue.erl
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+%%   The contents of this file are subject to the Mozilla Public License
+%%   Version 1.1 (the "License"); you may not use this file except in
+%%   compliance with the License. You may obtain a copy of the License at
+%%   http://www.mozilla.org/MPL/
+%%
+%%   Software distributed under the License is distributed on an "AS IS"
+%%   basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
+%%   License for the specific language governing rights and limitations
+%%   under the License.
+%%
+%%   The Original Code is RabbitMQ.
+%%
+%%   The Initial Developers of the Original Code are LShift Ltd,
+%%   Cohesive Financial Technologies LLC, and Rabbit Technologies Ltd.
+%%
+%%   Portions created before 22-Nov-2008 00:00:00 GMT by LShift Ltd,
+%%   Cohesive Financial Technologies LLC, or Rabbit Technologies Ltd
+%%   are Copyright (C) 2007-2008 LShift Ltd, Cohesive Financial
+%%   Technologies LLC, and Rabbit Technologies Ltd.
+%%
+%%   Portions created by LShift Ltd are Copyright (C) 2007-2009 LShift
+%%   Ltd. Portions created by Cohesive Financial Technologies LLC are
+%%   Copyright (C) 2007-2009 Cohesive Financial Technologies
+%%   LLC. Portions created by Rabbit Technologies Ltd are Copyright
+%%   (C) 2007-2009 Rabbit Technologies Ltd.
+%%
+%%   All Rights Reserved.
+%%
+%%   Contributor(s): ______________________________________.
+%%
+
+-module(rabbit_backing_queue).
+
+-export([behaviour_info/1]).
+
+behaviour_info(callbacks) ->
+    [
+     %% Called on startup with a list of durable queue names. The
+     %% queues aren't being started at this point, but this call
+     %% allows the backing queue to perform any checking necessary for
+     %% the consistency of those queues, or initialise any other
+     %% shared resources.
+     {start, 1},
+
+     %% Initialise the backing queue and its state.
+     {init, 3},
+
+     %% Called on queue shutdown when queue isn't being deleted.
+     {terminate, 1},
+
+     %% Called when the queue is terminating and needs to delete all
+     %% its content.
+     {delete_and_terminate, 1},
+
+     %% Remove all messages in the queue, but not messages which have
+     %% been fetched and are pending acks.
+     {purge, 1},
+
+     %% Publish a message.
+     {publish, 2},
+
+     %% Called for messages which have already been passed straight
+     %% out to a client. The queue will be empty for these calls
+     %% (i.e. saves the round trip through the backing queue).
+     {publish_delivered, 3},
+
+     %% Produce the next message.
+     {fetch, 2},
+
+     %% Acktags supplied are for messages which can now be forgotten
+     %% about.
+     {ack, 2},
+
+     %% A publish, but in the context of a transaction.
+     {tx_publish, 3},
+
+     %% Acks, but in the context of a transaction.
+     {tx_ack, 3},
+
+     %% Undo anything which has been done in the context of the
+     %% specified transaction.
+     {tx_rollback, 2},
+
+     %% Commit a transaction. The Fun passed in must be called once
+     %% the messages have really been commited. This CPS permits the
+     %% possibility of commit coalescing.
+     {tx_commit, 3},
+
+     %% Reinsert messages into the queue which have already been
+     %% delivered and were pending acknowledgement.
+     {requeue, 2},
+
+     %% How long is my queue?
+     {len, 1},
+
+     %% Is my queue empty?
+     {is_empty, 1},
+
+     %% For the next three functions, the assumption is that you're
+     %% monitoring something like the ingress and egress rates of the
+     %% queue. The RAM duration is thus the length of time represented
+     %% by the messages held in RAM given the current rates. If you
+     %% want to ignore all of this stuff, then do so, and return 0 in
+     %% ram_duration/1.
+
+     %% The target is to have no more messages in RAM than indicated
+     %% by the duration and the current queue rates.
+     {set_ram_duration_target, 2},
+
+     %% Optionally recalculate the duration internally (likely to be
+     %% just update your internal rates), and report how many seconds
+     %% the messages in RAM represent given the current rates of the
+     %% queue.
+     {ram_duration, 1},
+
+     %% Should 'sync' be called as soon as the queue process can
+     %% manage (either on an empty mailbox, or when a timer fires)?
+     {needs_sync, 1},
+
+     %% Called (eventually) after needs_sync returns 'true'. Note this
+     %% may be called more than once for each 'true' returned from
+     %% needs_sync.
+     {sync, 1},
+
+     %% Called immediately before the queue hibernates.
+     {handle_pre_hibernate, 1},
+
+     %% Exists for debugging purposes, to be able to expose state via
+     %% rabbitmqctl list_queues backing_queue_status
+     {status, 1}
+    ];
+behaviour_info(_Other) ->
+    undefined.