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<b>DB_ENV->txn_checkpoint</b>
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<b><pre>
#include <db.h>
<p>
int
DB_ENV->txn_checkpoint(const DB_ENV *env,
u_int32_t kbyte, u_int32_t min, u_int32_t flags);
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<b>Description: DB_ENV->txn_checkpoint</b>
<p>If there has been any logging activity in the database environment since
the last checkpoint, the DB_ENV->txn_checkpoint method flushes the underlying
memory pool, writes a checkpoint record to the log, and then flushes the
log.</p>
<p>The DB_ENV->txn_checkpoint method
returns a non-zero error value on failure
and 0 on success.
</p>
<p>The DB_ENV->txn_checkpoint method is the underlying method used by the <a href="../utility/db_checkpoint.html">db_checkpoint</a> utility.
See the <a href="../utility/db_checkpoint.html">db_checkpoint</a> utility source code for an example of using DB_ENV->txn_checkpoint
in a IEEE/ANSI Std 1003.1 (POSIX) environment.</p>
<b>Parameters</b> <br>
<b>flags</b><ul compact><li>The <b>flags</b> parameter must be set to 0 or
the following value:
<br>
<b><a name="DB_FORCE">DB_FORCE</a></b><ul compact><li>Force a checkpoint record, even if there has been no activity since the
last checkpoint.</ul>
<br></ul>
<b>kbyte</b><ul compact><li>If the <b>kbyte</b> parameter is non-zero, a checkpoint will be done
if more than <b>kbyte</b> kilobytes of log data have been written since
the last checkpoint.</ul>
<b>min</b><ul compact><li>If the <b>min</b> parameter is non-zero, a checkpoint will be done if
more than <b>min</b> minutes have passed since the last checkpoint.</ul>
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<br><b>Errors</b>
<p>The DB_ENV->txn_checkpoint method
may fail and 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_c/env_class.html">DB_ENV</a>, <a href="../api_c/txn_class.html">DB_TXN</a>
<br><b>See Also</b>
<a href="../api_c/txn_list.html">Transaction Subsystem and Related Methods</a>
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