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<h2 class="title" style="clear: both"><a id="txncheckpoint"></a>DbEnv::txn_checkpoint()</h2>
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<pre class="programlisting">#include <db_cxx.h>
int
DbEnv::txn_checkpoint(u_int32_t kbyte, u_int32_t min, u_int32_t flags) const;</pre>
<p>
If there has been any logging activity in the database environment
since the last checkpoint, the <code class="methodname">DbEnv::txn_checkpoint()</code> method
flushes the underlying memory pool, writes a checkpoint record to the
log, and then flushes the log.
</p>
<p>
The <code class="methodname">DbEnv::txn_checkpoint()</code> method returns a non-zero error value on
failure and 0 on success.
</p>
<p>
The <code class="methodname">DbEnv::txn_checkpoint()</code> method is the underlying method used by
the <a class="link" href="db_checkpoint.html" title="db_checkpoint">db_checkpoint</a>
utility. See the <a class="link" href="db_checkpoint.html" title="db_checkpoint">db_checkpoint</a> utility
source code for an example of using <code class="methodname">DbEnv::txn_checkpoint()</code> in a
IEEE/ANSI Std 1003.1 (POSIX) environment.
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<h3 class="title"><a id="id1714283"></a>Parameters</h3>
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<div class="sect3" lang="en" xml:lang="en">
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<h4 class="title"><a id="id1713843"></a>flags</h4>
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<p>
The <span class="bold"><strong>flags</strong></span> parameter must be set to 0
or the following value:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p>
<code class="literal">DB_FORCE</code>
</p>
<p>
Force a checkpoint record, even if there has been no activity since
the last checkpoint.
</p>
</li>
</ul>
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<div class="sect3" lang="en" xml:lang="en">
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<h4 class="title"><a id="id1714518"></a>kbyte</h4>
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<p>
If the <span class="bold"><strong>kbyte</strong></span> parameter is non-zero, a
checkpoint will be done if more than <span class="bold"><strong>kbyte</strong></span> kilobytes of log data have been written
since the last checkpoint.
</p>
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<h4 class="title"><a id="id1713821"></a>min</h4>
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<p>
If the <span class="bold"><strong>min</strong></span> parameter is non-zero, a
checkpoint will be done if more than <span class="bold"><strong>min</strong></span> minutes have passed since the last
checkpoint.
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<h3 class="title"><a id="id1714656"></a>Errors</h3>
</div>
</div>
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<p>
The <code class="methodname">DbEnv::txn_checkpoint()</code> <span>
<span>
method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a>
exception, encapsulating one of the following non-zero errors, or return one
of the following non-zero errors:
</span>
</span>
</p>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1714108"></a>EINVAL</h4>
</div>
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<p>
An invalid flag value or parameter was specified.
</p>
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<div class="sect2" lang="en" xml:lang="en">
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<div>
<h3 class="title"><a id="id1714444"></a>Class</h3>
</div>
</div>
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<p>
<a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a>, <a class="link" href="txn.html" title="Chapter 13. The DbTxn Handle">DbTxn</a>
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<h3 class="title"><a id="id1714432"></a>See Also</h3>
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<p>
<a class="xref" href="txn.html#txnlist" title="Transaction Subsystem and Related Methods">Transaction Subsystem and Related Methods</a>
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