diff --git a/include/ndnboost/iostreams/tee.hpp b/include/ndnboost/iostreams/tee.hpp
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+++ b/include/ndnboost/iostreams/tee.hpp
@@ -0,0 +1,232 @@
+// (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
+// (C) Copyright 2005-2007 Jonathan Turkanis
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
+
+// See http://www.boost.org/libs/iostreams for documentation.
+
+#ifndef NDNBOOST_IOSTREAMS_TEE_HPP_INCLUDED
+#define NDNBOOST_IOSTREAMS_TEE_HPP_INCLUDED
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+#include <ndnboost/assert.hpp>
+#include <ndnboost/config.hpp>  // NDNBOOST_DEDUCE_TYPENAME.
+#include <ndnboost/iostreams/categories.hpp>
+#include <ndnboost/iostreams/detail/adapter/device_adapter.hpp>
+#include <ndnboost/iostreams/detail/adapter/filter_adapter.hpp>
+#include <ndnboost/iostreams/detail/call_traits.hpp>
+#include <ndnboost/iostreams/detail/execute.hpp>
+#include <ndnboost/iostreams/detail/functional.hpp>  // call_close_all 
+#include <ndnboost/iostreams/operations.hpp>
+#include <ndnboost/iostreams/pipeline.hpp>
+#include <ndnboost/iostreams/traits.hpp>
+#include <ndnboost/static_assert.hpp>
+#include <ndnboost/type_traits/is_convertible.hpp>
+#include <ndnboost/type_traits/is_same.hpp>
+
+namespace ndnboost { namespace iostreams {
+
+//
+// Template name: tee_filter.
+// Template parameters:
+//      Device - A blocking Sink.
+//
+template<typename Device>
+class tee_filter : public detail::filter_adapter<Device> {
+public:
+    typedef typename detail::param_type<Device>::type  param_type;
+    typedef typename char_type_of<Device>::type        char_type;
+    struct category
+        : dual_use_filter_tag,
+          multichar_tag,
+          closable_tag,
+          flushable_tag,
+          localizable_tag,
+          optimally_buffered_tag
+        { };
+
+    NDNBOOST_STATIC_ASSERT(is_device<Device>::value);
+    NDNBOOST_STATIC_ASSERT((
+        is_convertible< // Using mode_of causes failures on VC6-7.0.
+            NDNBOOST_DEDUCED_TYPENAME iostreams::category_of<Device>::type, output
+        >::value
+    ));
+
+    explicit tee_filter(param_type dev) 
+        : detail::filter_adapter<Device>(dev) 
+        { }
+
+    template<typename Source>
+    std::streamsize read(Source& src, char_type* s, std::streamsize n)
+    {
+        std::streamsize result = iostreams::read(src, s, n);
+        if (result != -1) {
+            std::streamsize result2 = iostreams::write(this->component(), s, result);
+            (void) result2; // Suppress 'unused variable' warning.
+            NDNBOOST_ASSERT(result == result2);
+        }
+        return result;
+    }
+
+    template<typename Sink>
+    std::streamsize write(Sink& snk, const char_type* s, std::streamsize n)
+    {
+        std::streamsize result = iostreams::write(snk, s, n);
+        std::streamsize result2 = iostreams::write(this->component(), s, result);
+        (void) result2; // Suppress 'unused variable' warning.
+        NDNBOOST_ASSERT(result == result2);
+        return result;
+    }
+
+    template<typename Next>
+    void close(Next&, NDNBOOST_IOS::openmode)
+    { 
+        detail::close_all(this->component());
+    }
+
+    template<typename Sink>
+    bool flush(Sink& snk)
+    {
+        bool r1 = iostreams::flush(snk);
+        bool r2 = iostreams::flush(this->component());
+        return r1 && r2;
+    }
+};
+NDNBOOST_IOSTREAMS_PIPABLE(tee_filter, 1)
+
+//
+// Template name: tee_device.
+// Template parameters:
+//      Device - A blocking Device.
+//      Sink - A blocking Sink.
+//
+template<typename Device, typename Sink>
+class tee_device {
+public:
+    typedef typename detail::param_type<Device>::type  device_param;
+    typedef typename detail::param_type<Sink>::type    sink_param;
+    typedef typename detail::value_type<Device>::type  device_value;
+    typedef typename detail::value_type<Sink>::type    sink_value;
+    typedef typename char_type_of<Device>::type        char_type;
+    typedef typename
+            mpl::if_<
+                 is_convertible<
+                     NDNBOOST_DEDUCED_TYPENAME 
+                         iostreams::category_of<Device>::type, 
+                     output
+                 >,
+                 output,
+                 input
+            >::type                                    mode;
+    NDNBOOST_STATIC_ASSERT(is_device<Device>::value);
+    NDNBOOST_STATIC_ASSERT(is_device<Sink>::value);
+    NDNBOOST_STATIC_ASSERT((
+        is_same<
+            char_type, 
+            NDNBOOST_DEDUCED_TYPENAME char_type_of<Sink>::type
+        >::value
+    ));
+    NDNBOOST_STATIC_ASSERT((
+        is_convertible<
+            NDNBOOST_DEDUCED_TYPENAME iostreams::category_of<Sink>::type, 
+            output
+        >::value
+    ));
+    struct category
+        : mode,
+          device_tag,
+          closable_tag,
+          flushable_tag,
+          localizable_tag,
+          optimally_buffered_tag
+        { };
+    tee_device(device_param device, sink_param sink) 
+        : dev_(device), sink_(sink)
+        { }
+    std::streamsize read(char_type* s, std::streamsize n)
+    {
+        NDNBOOST_STATIC_ASSERT((
+            is_convertible<
+                NDNBOOST_DEDUCED_TYPENAME iostreams::category_of<Device>::type, input
+            >::value
+        ));
+        std::streamsize result1 = iostreams::read(dev_, s, n);
+        if (result1 != -1) {
+            std::streamsize result2 = iostreams::write(sink_, s, result1);
+            (void) result1; // Suppress 'unused variable' warning.
+            (void) result2;
+            NDNBOOST_ASSERT(result1 == result2);
+        }
+        return result1;
+    }
+    std::streamsize write(const char_type* s, std::streamsize n)
+    {
+        NDNBOOST_STATIC_ASSERT((
+            is_convertible<
+                NDNBOOST_DEDUCED_TYPENAME iostreams::category_of<Device>::type, output
+            >::value
+        ));
+        std::streamsize result1 = iostreams::write(dev_, s, n);
+        std::streamsize result2 = iostreams::write(sink_, s, n);
+        (void) result1; // Suppress 'unused variable' warning.
+        (void) result2;
+        NDNBOOST_ASSERT(result1 == n && result2 == n);
+        return n;
+    }
+    void close()
+    {
+        detail::execute_all( detail::call_close_all(dev_),
+                             detail::call_close_all(sink_) );
+    }
+    bool flush()
+    {
+        bool r1 = iostreams::flush(dev_);
+        bool r2 = iostreams::flush(sink_);
+        return r1 && r2;
+    }
+    template<typename Locale>
+    void imbue(const Locale& loc)
+    {
+        iostreams::imbue(dev_, loc);
+        iostreams::imbue(sink_, loc);
+    }
+    std::streamsize optimal_buffer_size() const 
+    {
+        return (std::max) ( iostreams::optimal_buffer_size(dev_), 
+                            iostreams::optimal_buffer_size(sink_) );
+    }
+private:
+    device_value  dev_;
+    sink_value    sink_;
+};
+
+template<typename Sink>
+tee_filter<Sink> tee(Sink& snk) 
+{ return tee_filter<Sink>(snk); }
+
+template<typename Sink>
+tee_filter<Sink> tee(const Sink& snk) 
+{ return tee_filter<Sink>(snk); }
+
+template<typename Device, typename Sink>
+tee_device<Device, Sink> tee(Device& dev, Sink& sink) 
+{ return tee_device<Device, Sink>(dev, sink); }
+
+template<typename Device, typename Sink>
+tee_device<Device, Sink> tee(const Device& dev, Sink& sink) 
+{ return tee_device<Device, Sink>(dev, sink); }
+
+template<typename Device, typename Sink>
+tee_device<Device, Sink> tee(Device& dev, const Sink& sink) 
+{ return tee_device<Device, Sink>(dev, sink); }
+
+template<typename Device, typename Sink>
+tee_device<Device, Sink> tee(const Device& dev, const Sink& sink) 
+{ return tee_device<Device, Sink>(dev, sink); }
+
+} } // End namespaces iostreams, boost.
+
+#endif // #ifndef NDNBOOST_IOSTREAMS_TEE_HPP_INCLUDED