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DbMpoolFile
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#include &lt;db_cxx.h&gt;

class DbMpoolFile {
public:
	DB_MPOOLFILE *DbMpoolFile::get_DB_MPOOLFILE();
	const DB_MPOOLFILE *DbMpoolFile::get_const_DB_MPOOLFILE() const;
	...
};
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Description: DbMpoolFile
The memory pool interfaces for the Berkeley DB database environment are
methods of the <a href="../../db4-devel-4.7.25/api_cxx/env_class.html">DbEnv</a> handle. The <a href="../../db4-devel-4.7.25/api_cxx/env_class.html">DbEnv</a> memory pool
methods and the DbMpoolFile class provide general-purpose,
page-oriented buffer management of files. Although designed to work
with the other <a href="../../db4-devel-4.7.25/api_cxx/db_class.html">Db</a> classes, they are also useful for more general
purposes. The memory pools are referred to in this document as simply
pools.
Pools may be shared between processes. Pools are usually filled by
pages from one or more files. Pages in the pool are replaced in LRU
(least-recently-used) order, with each new page replacing the page that
has been unused the longest. Pages retrieved from the pool using
<a href="../../db4-devel-4.7.25/api_cxx/memp_fget.html">DbMpoolFile::get</a> are pinned in the pool until they are
returned to the control of the buffer pool using the <a href="../../db4-devel-4.7.25/api_cxx/memp_fput.html">DbMpoolFile::put</a>
method.
The DbMpoolFile object is the handle for a file in the memory
pool. The handle is not free-threaded. Once the <a href="../../db4-devel-4.7.25/api_cxx/memp_fclose.html">DbMpoolFile::close</a> method
is called, the handle may not be accessed again, regardless of that
method's return.
Each DbMpoolFile object has an associated DB_MPOOLFILE
structure, which is used by the underlying implementation of Berkeley DB and
its C-language API. The DbMpoolFile::get_DB_MPOOLFILE method returns a
pointer to this struct. Given a const DbMpoolFile object,
DbMpoolFile::get_const_DB_MPOOLFILE returns a const pointer to the same
struct.
These methods may be useful for Berkeley DB applications including both C
and C++ language software. It should not be necessary to use these
calls in a purely C++ application.
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 Class
<a href="../../db4-devel-4.7.25/api_cxx/env_class.html">DbEnv</a>, DbMpoolFile
 See Also
<a href="../../db4-devel-4.7.25/api_cxx/memp_list.html">Memory Pools and Related Methods</a>
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