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<div class="sect1" lang="en" xml:lang="en">
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<h2 class="title" style="clear: both"><a id="envadd_data_dir"></a>DB_ENV-&gt;add_data_dir()</h2>
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<pre class="programlisting">#include &lt;db.h&gt;
int
DB_ENV-&gt;add_data_dir(DB_ENV *dbenv, const char *dir); </pre>
<p>
Add the path of a directory to be used as the location of the access
method database files. Paths specified to the
<a class="xref" href="dbopen.html" title="DB-&gt;open()">DB-&gt;open()</a> function will be
searched relative to this path. Paths set using this method are
additive, and specifying more than one will result in each specified
directory being searched for database files.
</p>
<p>
If no database directories are specified, database files must be named
either by absolute paths or relative to the environment home
directory. See
<a href="../../programmer_reference/env_naming.html" class="olink">Berkeley DB File Naming</a>
for more information.
</p>
<p>
The database environment's data directories may also be configured
using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. The syntax of the entry
in that file is a single line with the string "add_data_dir", one
or more whitespace characters, and the directory name.
Note that if you use this method for your application, and you also want to use the
<a class="xref" href="db_recover.html" title="db_recover">db_recover</a> or
<a class="xref" href="db_archive.html" title="db_archive">db_archive</a>
utilities, then you should create a <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file and set
the "add_data_dir" parameter in it.
</p>
<p>
The <code class="methodname">DB_ENV-&gt;add_data_dir()</code> method configures operations performed
using the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>
handle, not all operations performed on the underlying database environment.
</p>
<p>
The <code class="methodname">DB_ENV-&gt;add_data_dir()</code> method may not be called after the
<a class="xref" href="envopen.html" title="DB_ENV-&gt;open()">DB_ENV-&gt;open()</a> method is called.
If the database environment already exists when
<a class="xref" href="envopen.html" title="DB_ENV-&gt;open()">DB_ENV-&gt;open()</a> is called, the
information specified to <code class="methodname">DB_ENV-&gt;add_data_dir()</code> must be consistent
with the existing environment or corruption can occur.
</p>
<p>
The <code class="methodname">DB_ENV-&gt;add_data_dir()</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="idp59222632"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp59208304"></a>dir</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>dir</strong></span> parameter is a
directory to be used as a location for database files.
This directory must currently exist at environment open
time.
</p>
<p>
When using a Unicode build on Windows (the default), this
argument will be interpreted as a UTF-8 string, which is
equivalent to ASCII for Latin characters.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp59226264"></a>Errors</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DB_ENV-&gt;add_data_dir()</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="idp59240872"></a>EINVAL</h4>
</div>
</div>
</div>
<p>
If the method was called after <a class="xref" href="envopen.html" title="DB_ENV-&gt;open()">DB_ENV-&gt;open()</a>
was called; or if 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="idp59239792"></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="idp59208496"></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>
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