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<b>DbMpoolFile::set_flags</b>
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<b><pre>
#include &lt;db_cxx.h&gt;
<p>
int
DbMpoolFile::set_flags(u_int32_t flags, bool onoff);
<p>
int
DbMpoolFile::get_flags(u_int32_t *flagsp);
</pre></b>
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<b>Description: DbMpoolFile::set_flags</b>
<p>Configure a file in the cache.</p>
<p>To set the flags for a particular database, call the
DbMpoolFile::set_flags method using the <a href="../api_cxx/mempfile_class.html">DbMpoolFile</a> handle stored in
the <b>mpf</b> field of the <a href="../api_cxx/db_class.html">Db</a> handle.</p>
<p>The DbMpoolFile::set_flags method
either returns a non-zero error value
or throws an exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</p>
<b>Parameters</b> <br>
 <b>flags</b><ul compact><li>The <b>flags</b> parameter must be set by bitwise inclusively <b>OR</b>'ing together one or more
of the following values:
<br>
<b><a name="DB_MPOOL_NOFILE">DB_MPOOL_NOFILE</a></b><ul compact><li>If set, no backing temporary file will be opened for the specified
in-memory database, even if it expands to fill the entire cache.
Attempts to create new database pages after the cache has been filled
will fail.
<p>The DB_MPOOL_NOFILE flag configures a file in the memory pool, not only
operations performed using the specified <a href="../api_cxx/mempfile_class.html">DbMpoolFile</a> handle.</p>
<p>The DB_MPOOL_NOFILE flag may be used to configure Berkeley DB at any time during
the life of the application.</p></ul>
<b><a name="DB_MPOOL_UNLINK">DB_MPOOL_UNLINK</a></b><ul compact><li>If set, remove the file when the last reference to it is closed.
<p>The DB_MPOOL_NOFILE flag configures a file in the memory pool, not only
operations performed using the specified <a href="../api_cxx/mempfile_class.html">DbMpoolFile</a> handle.</p>
<p>The DB_MPOOL_UNLINK flag may be used to configure Berkeley DB at any time during
the life of the application.</p></ul>
<br></ul>
 <b>onoff</b><ul compact><li>If <b>onoff</b> is
false,
the specified flags are cleared;  otherwise they are set.</ul>
<br>
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<b>Description: DbMpoolFile::get_flags</b>
<p>The DbMpoolFile::get_flags method returns the flags.</p>
<p>The DbMpoolFile::get_flags method may be called at any time during the life of the
application.</p>
<p>The DbMpoolFile::get_flags method
either returns a non-zero error value
or throws an exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</p>
<b>Parameters</b> <br>
 <b>flagsp</b><ul compact><li>The DbMpoolFile::get_flags method returns  the
flags in <b>flagsp</b>.</ul>
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<br><b>Class</b>
<a href="../api_cxx/env_class.html">DbEnv</a>, <a href="../api_cxx/mempfile_class.html">DbMpoolFile</a>
<br><b>See Also</b>
<a href="../api_cxx/memp_list.html">Memory Pools and Related Methods</a>
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