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<p>Library Version 11.2.5.3</p>
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<th colspan="3" align="center">DB_ENV-&gt;lsn_reset()</th>
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<td width="20%" align="left"><a accesskey="p" href="envlog_verify.html">Prev</a> </td>
<th width="60%" align="center">Chapter 5. 
The DB_ENV Handle
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<div class="sect1" lang="en" xml:lang="en">
<div class="titlepage">
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<div>
<h2 class="title" style="clear: both"><a id="envlsn_reset"></a>DB_ENV-&gt;lsn_reset()</h2>
</div>
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</div>
<pre class="programlisting">#include &lt;db.h&gt;
int
DB_ENV-&gt;lsn_reset(DB_ENV *dbenv, const char *file, u_int32_t flags); </pre>
<p>
The <code class="methodname">DB_ENV-&gt;lsn_reset()</code> method allows database files to be moved from
one transactional database environment to another.
</p>
<p>
Database pages in transactional database environments contain
references to the environment's log files (that is, log sequence
numbers, or LSNs). Copying or moving a database file from one database
environment to another, and then modifying it, can result in data
corruption if the LSNs are not first cleared.
</p>
<p>
Note that LSNs should be reset before moving or copying the database
file into a new database environment, rather than moving or copying
the database file and then resetting the LSNs. Berkeley DB has
consistency checks that may be triggered if an application calls
<code class="methodname">DB_ENV-&gt;lsn_reset()</code> on a database in a new environment when the
database LSNs still reflect the old environment.
</p>
<p>
The <code class="methodname">DB_ENV-&gt;lsn_reset()</code> method modifies the physical file, in-place.
Applications should not reset LSNs in files that are currently in use.
</p>
<p>
The <code class="methodname">DB_ENV-&gt;lsn_reset()</code> method may be called at any time during the
life of the application.
</p>
<p>
The <code class="methodname">DB_ENV-&gt;lsn_reset()</code> <span>
<span>
method returns a non-zero error value on failure and 0 on success.
</span>
</span>
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp59643680"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp59643336"></a>file</h4>
</div>
</div>
</div>
<p>
The name of the physical file in which the LSNs are to be cleared.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp59649776"></a>flags</h4>
</div>
</div>
</div>
<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_ENCRYPT</code>
</p>
<p>
The file contains encrypted databases.
</p>
</li>
</ul>
</div>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp59650960"></a>Errors</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DB_ENV-&gt;lsn_reset()</code> <span>
<span>
method may fail and 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="idp59655856"></a>EINVAL</h4>
</div>
</div>
</div>
<p>
An invalid flag value or parameter was specified.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp59654560"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>
</p>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp59656936"></a>See Also</h3>
</div>
</div>
</div>
<p>
<a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments and Related Methods</a>
</p>
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