diff --git a/common/rdr/FixedMemOutStream.h b/common/rdr/FixedMemOutStream.h
new file mode 100644
index 0000000..e4ec52c
--- /dev/null
+++ b/common/rdr/FixedMemOutStream.h
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+/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
+ * 
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this software; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+ * USA.
+ */
+
+//
+// A FixedMemOutStream writes to a buffer of a fixed length.
+//
+
+#ifndef __RDR_FIXEDMEMOUTSTREAM_H__
+#define __RDR_FIXEDMEMOUTSTREAM_H__
+
+#include <rdr/OutStream.h>
+#include <rdr/Exception.h>
+
+namespace rdr {
+
+  class FixedMemOutStream : public OutStream {
+
+  public:
+
+    FixedMemOutStream(void* buf, int len) {
+      ptr = start = (U8*)buf;
+      end = start + len;
+    }
+
+    int length() { return ptr - start; }
+    void reposition(int pos) { ptr = start + pos; }
+    const void* data() { return (const void*)start; }
+
+  private:
+
+    int overrun(int itemSize, int nItems) { throw EndOfStream(); }
+    U8* start;
+  };
+
+}
+
+#endif