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<h2 class="title" style="clear: both"><a id="envget_backup_callbacks"></a>DbEnv::get_backup_callbacks()</h2>
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<pre class="programlisting">#include <db_cxx.h>
DB_ENV->get_backup_callbacks(
int (**open_func)(DB_ENV *, const char *dbname,
const char *target, void **handle),
int (**write_func)(DB_ENV *, u_int32_t offset_gbytes,
u_int32_t offset_bytes, u_int32_t size,
u_int8_t *buf, void *handle),
int (**close_func)(DB_ENV *, const char *dbname, void *handle)); </pre>
<p>
The <code class="methodname">DbEnv::get_backup_callbacks()</code> method
retrieves the three callback functions which can be used by the
<a class="xref" href="envbackup.html" title="DbEnv::backup()">DbEnv::backup()</a>
or
<a class="xref" href="envdbbackup.html" title="DbEnv::dbbackup()">DbEnv::dbbackup()</a>
methods to override their default behavior. These callbacks are
configured using the
<a class="xref" href="envset_backup_callbacks.html" title="DbEnv::set_backup_callbacks()">DbEnv::set_backup_callbacks()</a>
method.
</p>
<p>
The <code class="methodname">DbEnv::get_backup_callbacks()</code> method may
be called at any time during the life of the application.
</p>
<p>
The <code class="methodname">DbEnv::get_backup_callbacks()</code> <span>
<span>
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.
</span>
</span>
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<div class="sect2" lang="en" xml:lang="en">
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<h3 class="title"><a id="idp1468696"></a>Parameters</h3>
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<h4 class="title"><a id="idp1468048"></a>open_func</h4>
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<p>
The <span class="bold"><strong>open_func</strong></span> parameter
is the function used when a target location is opened
during a backup.
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<h4 class="title"><a id="idp1457144"></a>write_func</h4>
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<p>
The <span class="bold"><strong>close_func</strong></span> parameter
is the function used to write data during a backup.
</p>
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<h4 class="title"><a id="idp1459040"></a>close_func</h4>
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<p>
The <span class="bold"><strong>close_func</strong></span> parameter
is the function used when ending a backup and closing a
backup target.
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<h3 class="title"><a id="idp1472104"></a>Class</h3>
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<a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a>
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<h3 class="title"><a id="idp1463712"></a>See Also</h3>
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<p>
<a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments and Related Methods</a>,
<a class="xref" href="envset_backup_callbacks.html" title="DbEnv::set_backup_callbacks()">DbEnv::set_backup_callbacks()</a>,
<a class="xref" href="envbackup.html" title="DbEnv::backup()">DbEnv::backup()</a>, and
<a class="xref" href="envdbbackup.html" title="DbEnv::dbbackup()">DbEnv::dbbackup()</a>.
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