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diff --git a/qpid/cpp/src/qpid/sys/AggregateOutput.h b/qpid/cpp/src/qpid/sys/AggregateOutput.h
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+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ *
+ */
+#ifndef _AggregateOutput_
+#define _AggregateOutput_
+
+#include "qpid/sys/Monitor.h"
+#include "qpid/sys/OutputControl.h"
+#include "qpid/sys/OutputTask.h"
+#include "qpid/CommonImportExport.h"
+
+#include <algorithm>
+#include <deque>
+
+namespace qpid {
+namespace sys {
+
+/**
+ * Holds a collection of output tasks, doOutput picks the next one to execute.
+ * 
+ * Tasks are automatically removed if their doOutput() or hasOutput() returns false.
+ * 
+ * Thread safe. addOutputTask may be called in one connection thread while
+ * doOutput is called in another.
+ */
+
+class QPID_COMMON_CLASS_EXTERN AggregateOutput : public OutputTask, public OutputControl
+{
+    typedef std::deque<OutputTask*> TaskList;
+
+    Monitor lock;
+    TaskList tasks;
+    bool busy;
+    OutputControl& control;
+
+  public:
+    QPID_COMMON_EXTERN AggregateOutput(OutputControl& c);
+
+    // These may be called concurrently with any function.
+    QPID_COMMON_EXTERN void abort();
+    QPID_COMMON_EXTERN void activateOutput();
+    QPID_COMMON_EXTERN void giveReadCredit(int32_t);
+    QPID_COMMON_EXTERN void addOutputTask(OutputTask* t);
+
+    // These functions must not be called concurrently with each other.
+    QPID_COMMON_EXTERN bool doOutput();
+    QPID_COMMON_EXTERN void removeOutputTask(OutputTask* t);
+    QPID_COMMON_EXTERN void removeAll();
+
+    /** Apply f to each OutputTask* in the tasks list */
+    template <class F> void eachOutput(F f) {
+        Mutex::ScopedLock l(lock);
+        std::for_each(tasks.begin(), tasks.end(), f);
+    }
+};
+
+}} // namespace qpid::sys
+
+
+#endif