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diff --git a/apps/couch/src/couch_db_update_notifier.erl b/apps/couch/src/couch_db_update_notifier.erl
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+++ b/apps/couch/src/couch_db_update_notifier.erl
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+% Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+%
+% Unless required by applicable law or agreed to in writing, software
+% distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+% WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+% License for the specific language governing permissions and limitations under
+% the License.
+
+%
+% This causes an OS process to spawned and it is notified every time a database
+% is updated.
+%
+% The notifications are in the form of a the database name sent as a line of
+% text to the OS processes stdout.
+%
+
+-module(couch_db_update_notifier).
+
+-behaviour(gen_event).
+
+-export([start_link/1, notify/1]).
+-export([init/1, terminate/2, handle_event/2, handle_call/2, handle_info/2, code_change/3,stop/1]).
+
+-include("couch_db.hrl").
+
+start_link(Exec) ->
+    couch_event_sup:start_link(couch_db_update, {couch_db_update_notifier, make_ref()}, Exec).
+
+notify(Event) ->
+    gen_event:notify(couch_db_update, Event).
+
+stop(Pid) ->
+    couch_event_sup:stop(Pid).
+
+init(Exec) when is_list(Exec) -> % an exe
+    couch_os_process:start_link(Exec, []);
+init(Else) ->
+    {ok, Else}.
+
+terminate(_Reason, Pid) when is_pid(Pid) ->
+    couch_os_process:stop(Pid),
+    ok;
+terminate(_Reason, _State) ->
+    ok.
+
+handle_event(Event, Fun) when is_function(Fun, 1) ->
+    Fun(Event),
+    {ok, Fun};
+handle_event(Event, {Fun, FunAcc}) ->
+    FunAcc2 = Fun(Event, FunAcc),
+    {ok, {Fun, FunAcc2}};
+handle_event({EventAtom, DbName}, Pid) ->
+    Obj = {[{type, list_to_binary(atom_to_list(EventAtom))}, {db, DbName}]},
+    ok = couch_os_process:send(Pid, Obj),
+    {ok, Pid}.
+
+handle_call(_Request, State) ->
+    {reply, ok, State}.
+
+handle_info({'EXIT', Pid, Reason}, Pid) ->
+    ?LOG_ERROR("Update notification process ~p died: ~p", [Pid, Reason]),
+    remove_handler;
+handle_info({'EXIT', _, _}, Pid) ->
+    %% the db_update event manager traps exits and forwards this message to all
+    %% its handlers. Just ignore as it wasn't our os_process that exited.
+    {ok, Pid}.
+
+code_change(_OldVsn, State, _Extra) ->
+    {ok, State}.