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<b>DbEnv::lsn_reset</b>
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<b><pre>
#include <db_cxx.h>
<p>
int
DbEnv::lsn_reset(const char *file, u_int32_t flags);
</pre></b>
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<b>Description: DbEnv::lsn_reset</b>
<p>The DbEnv::lsn_reset 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 DbEnv::lsn_reset
on a database in a new environment when the database LSNs still reflect
the old environment.</p>
<p>The DbEnv::lsn_reset method modifies the physical file, in-place.
Applications should not reset LSNs in files that are currently in use.</p>
<p>The DbEnv::lsn_reset method may be called at any time during the life of the
application.</p>
<p>The DbEnv::lsn_reset 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>file</b><ul compact><li>The name of the physical file in which the LSNs are to be cleared.</ul>
<b>flags</b><ul compact><li>The <b>flags</b> parameter must be set to 0 or
the following value:
<br>
<b>DB_ENCRYPT</b><ul compact><li>The file contains encrypted databases.</ul>
<br></ul>
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<br><b>Errors</b>
<p>The DbEnv::lsn_reset method
may fail and throw
<a href="../api_cxx/except_class.html">DbException</a>,
encapsulating one of the following non-zero errors, or return one of
the following non-zero errors:</p>
<br>
<b>EINVAL</b><ul compact><li>An
invalid flag value or parameter was specified.</ul>
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<br><b>Class</b>
<a href="../api_cxx/env_class.html">DbEnv</a>
<br><b>See Also</b>
<a href="../api_cxx/env_list.html">Database Environments and Related Methods</a>
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