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diff --git a/qpid/cpp/src/qpid/sys/MemoryMappedFile.h b/qpid/cpp/src/qpid/sys/MemoryMappedFile.h
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+#ifndef QPID_SYS_MEMORYMAPPEDFILE_H
+#define QPID_SYS_MEMORYMAPPEDFILE_H
+
+/*
+ *
+ * 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.
+ *
+ */
+#include "qpid/CommonImportExport.h"
+#include <string>
+
+namespace qpid {
+namespace sys {
+
+class MemoryMappedFilePrivate;
+/**
+ * Abstraction of memory mapping functionality
+ */
+class MemoryMappedFile {
+ public:
+ QPID_COMMON_EXTERN MemoryMappedFile();
+ QPID_COMMON_EXTERN ~MemoryMappedFile();
+ /**
+ * Opens a file that can be mapped by region into memory
+ */
+ QPID_COMMON_EXTERN void open(const std::string& name, const std::string& directory);
+ /**
+ * Closes and removes the file that can be mapped by region into memory
+ */
+ QPID_COMMON_EXTERN void close();
+ /**
+ * Returns the page size
+ */
+ QPID_COMMON_EXTERN size_t getPageSize();
+ /**
+ * Load a portion of the file into memory
+ */
+ QPID_COMMON_EXTERN char* map(size_t offset, size_t size);
+ /**
+ * Evict a portion of the file from memory
+ */
+ QPID_COMMON_EXTERN void unmap(char* region, size_t size);
+ /**
+ * Flush any changes to a previously mapped region of the file
+ * back to disk
+ */
+ QPID_COMMON_EXTERN void flush(char* region, size_t size);
+ /**
+ * Expand the capacity of the file
+ */
+ QPID_COMMON_EXTERN void expand(size_t offset);
+ /**
+ * Returns true if memory mapping is supported, false otherwise
+ */
+ QPID_COMMON_EXTERN static bool isSupported();
+ private:
+ MemoryMappedFilePrivate* state;
+
+ MemoryMappedFile(const MemoryMappedFile&);
+ MemoryMappedFile& operator=(const MemoryMappedFile&);
+};
+}} // namespace qpid::sys
+
+#endif /*!QPID_SYS_MEMORYMAPPEDFILE_H*/