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<h2 class="title" style="clear: both"><a id="mempset_pgcookie"></a>DbMpoolFile::set_pgcookie()</h2>
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<pre class="programlisting">#include <db_cxx.h>
int
DbMpoolFile::set_pgcookie(DBT *pgcookie); </pre>
<p>
The <code class="methodname">DbMpoolFile::set_pgcookie()</code> method specifies a byte string that
is provided to the functions registered to do input or output
processing of the file's pages as they are read from or written to,
the backing filesystem store. (See the
<a class="xref" href="mempregister.html" title="DbEnv::memp_register()">DbEnv::memp_register()</a>
documentation for more information.)
</p>
<p>
The <code class="methodname">DbMpoolFile::set_pgcookie()</code> method configures a file in the
cache, not only operations performed using the specified
<a class="link" href="memp.html" title="Chapter 9. The DbMpoolFile Handle">DbMpoolFile</a> handle.
</p>
<p>
The <code class="methodname">DbMpoolFile::set_pgcookie()</code> method may not be called after the
<a class="xref" href="mempfopen.html" title="DbMpoolFile::open()">DbMpoolFile::open()</a>
method is called. If the file is already open in the cache when
<a class="xref" href="mempfopen.html" title="DbMpoolFile::open()">DbMpoolFile::open()</a> is
called, the information specified to <code class="methodname">DbMpoolFile::set_pgcookie()</code>
will replace the existing information.
</p>
<p>
The <code class="methodname">DbMpoolFile::set_pgcookie()</code> <span>
<span>
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.
</span>
</span>
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<h3 class="title"><a id="id1697535"></a>Parameters</h3>
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<h4 class="title"><a id="id1697466"></a>pgcookie</h4>
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<p>
The <span class="bold"><strong>pgcookie</strong></span> parameter is a byte
string provided to the functions registered to do input or output
processing of the file's pages.
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<h3 class="title"><a id="id1697742"></a>Class</h3>
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<a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a>, <a class="link" href="memp.html" title="Chapter 9. The DbMpoolFile Handle">DbMpoolFile</a>
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<h3 class="title"><a id="id1697686"></a>See Also</h3>
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<a class="xref" href="memp.html#memplist" title="Memory Pools and Related Methods">Memory Pools and Related Methods</a>
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