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<h2 class="title" style="clear: both"><a id="mempset_mp_max_openfd"></a>DB_ENV->set_mp_max_openfd()</h2>
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<pre class="programlisting">#include <db.h>
int
DB_ENV->set_mp_max_openfd(DB_ENV *env, int maxopenfd); </pre>
<p>
The <code class="methodname">DB_ENV->set_mp_max_openfd()</code> method limits the number of file
descriptors the library will open concurrently when flushing dirty
pages from the cache.
</p>
<p>
The database environment's limit on open file descriptors to flush
dirty pages may also be configured using the environment's
<a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. The
syntax of the entry in that file is a single line with the string
"set_mp_max_openfd", one or more whitespace characters, and the number of
open file descriptors. Because the
<a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is
read when the database environment is opened, it will silently
overrule configuration done before that time.
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<p>
The <a class="xref" href="mempset_mp_max_openfd.html" title="DB_ENV->set_mp_max_openfd()">DB_ENV->set_mp_max_openfd()</a>
method configures a database environment, not only operations
performed using the specified <a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a> handle.
</p>
<p>
The <code class="methodname">DB_ENV->set_mp_max_openfd()</code> <span>
<span>
method returns a non-zero error value on failure and 0 on success.
</span>
</span>
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<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
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<h3 class="title"><a id="idp53183128"></a>Parameters</h3>
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<div class="sect3" lang="en" xml:lang="en">
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<div>
<h4 class="title"><a id="idp53165816"></a>maxopenfd</h4>
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<p>
The maximum number of file descriptors that may be concurrently opened
by the library when flushing dirty pages from the cache.
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<h3 class="title"><a id="idp53181896"></a>Errors</h3>
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<p>
The <code class="methodname">DB_ENV->set_mp_max_openfd()</code> <span>
<span>
method may fail and return one of the following non-zero errors:
</span>
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<h4 class="title"><a id="idp53149896"></a>EINVAL</h4>
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An invalid flag value or parameter was specified.
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<h3 class="title"><a id="idp53182160"></a>Class</h3>
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<a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a>, <a class="link" href="memp.html" title="Chapter 8. The DB_MPOOLFILE Handle">DB_MPOOLFILE</a>
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<h3 class="title"><a id="idp53194856"></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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