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diff --git a/src/dmon.erl b/src/dmon.erl
new file mode 100644
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+++ b/src/dmon.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 Developer of the Original Code is VMware, Inc.
+%% Copyright (c) 2011-2013 VMware, Inc.  All rights reserved.
+%%
+
+-module(dmon).
+
+-export([new/0, monitor/2, monitor_all/2, demonitor/2, is_monitored/2, erase/2,
+         monitored/1, is_empty/1]).
+
+-compile({no_auto_import, [monitor/2]}).
+
+-ifdef(use_specs).
+
+%%----------------------------------------------------------------------------
+
+-export_type([?MODULE/0]).
+
+-opaque(?MODULE()    :: dict()).
+
+-type(item()         :: pid() | {atom(), node()}).
+
+-spec(new/0          :: () -> ?MODULE()).
+-spec(monitor/2      :: (item(), ?MODULE()) -> ?MODULE()).
+-spec(monitor_all/2  :: ([item()], ?MODULE()) -> ?MODULE()).
+-spec(demonitor/2    :: (item(), ?MODULE()) -> ?MODULE()).
+-spec(is_monitored/2 :: (item(), ?MODULE()) -> boolean()).
+-spec(erase/2        :: (item(), ?MODULE()) -> ?MODULE()).
+-spec(monitored/1    :: (?MODULE()) -> [item()]).
+-spec(is_empty/1     :: (?MODULE()) -> boolean()).
+
+-endif.
+
+new() -> dict:new().
+
+monitor(Item, M) ->
+    case dict:is_key(Item, M) of
+        true  -> M;
+        false -> dict:store(Item, delegate:monitor(Item), M)
+    end.
+
+monitor_all([],     M) -> M;                %% optimisation
+monitor_all([Item], M) -> monitor(Item, M); %% optimisation
+monitor_all(Items,  M) -> lists:foldl(fun monitor/2, M, Items).
+
+demonitor(Item, M) ->
+    case dict:find(Item, M) of
+        {ok, MRef} -> delegate:demonitor(Item, MRef),
+                      dict:erase(Item, M);
+        error      -> M
+    end.
+
+is_monitored(Item, M) -> dict:is_key(Item, M).
+
+erase(Item, M) -> dict:erase(Item, M).
+
+monitored(M) -> dict:fetch_keys(M).
+
+is_empty(M) -> dict:size(M) == 0.