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<th colspan="3" align="center">DB_ENV-&gt;dbbackup()</th>
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<td width="20%" align="left"><a accesskey="p" href="envcreate.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">
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<h2 class="title" style="clear: both"><a id="envdbbackup"></a>DB_ENV-&gt;dbbackup()</h2>
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<pre class="programlisting">#include &lt;db.h&gt;
int
DB_ENV-&gt;dbbackup(DB_ENV *dbenv, const char *dbfile, const char *target,
u_int32_t flags); </pre>
<p>
The <code class="methodname">DB_ENV-&gt;dbbackup()</code> method performs a hot
backup of a single database file contained within the environment.
</p>
<p>
To back up an entire environment, use the
<a class="xref" href="envbackup.html" title="DB_ENV-&gt;backup()">DB_ENV-&gt;backup()</a>
method.
</p>
<p>
This method's default behavior can be changed by setting backup
callbacks. See
<a class="xref" href="envset_backup_callbacks.html" title="DB_ENV-&gt;set_backup_callbacks()">DB_ENV-&gt;set_backup_callbacks()</a>
for more information. Additional tuning parameters can also be set
using the
<a class="xref" href="envset_backup_config.html" title="DB_ENV-&gt;set_backup_config()">DB_ENV-&gt;set_backup_config()</a> method.
</p>
<p>
The <code class="methodname">DB_ENV-&gt;dbbackup()</code> method may only be
called after the environment handle has been opened.
</p>
<p>
The <code class="methodname">DB_ENV-&gt;dbbackup()</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="idp59290424"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp59302120"></a>dbfile</h4>
</div>
</div>
</div>
<p>
Identifies the database file that you want to back up.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp59314064"></a>target</h4>
</div>
</div>
</div>
<p>
Identifies the directory in which the back up will be
placed. This target must exist; otherwise this method
exits with an <code class="literal">ENOENT</code> error return.
</p>
<p>
Note that if the backup callbacks are set, then the value
specified to this parameter is passed on to the
<code class="literal">open_func()</code> callback. If this
parameter is NULL, then the target must be specified
directly to the <code class="literal">open_func()</code> callback.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp59306432"></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_EXCL</code>
</p>
<p>
Return an <code class="literal">EEXIST</code> error if a
target backup file already exists.
</p>
</li>
</ul>
</div>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp59316512"></a>Errors</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DB_ENV-&gt;dbbackup()</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="idp59317048"></a>EEXIST</h4>
</div>
</div>
</div>
<p>
<code class="literal">DB_EXCL</code> was specified for the
<code class="literal">flags</code> parameter, and an existing target
file was discovered when attempting to back up a source
file.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp59323104"></a>ENOENT</h4>
</div>
</div>
</div>
<p>
The target directory does not exist.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp59316216"></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="idp59312104"></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="idp59324312"></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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