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<h2 class="title" style="clear: both"><a id="envset_errfile"></a>DB_ENV->set_errfile()</h2>
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<pre class="programlisting">#include <db.h>
void
DB_ENV->set_errfile(DB_ENV *dbenv, FILE *errfile); </pre>
<p>
When an error occurs in the Berkeley DB library,
<span>
a Berkeley DB error
</span>
or an error return value is returned by the interface. In some cases,
however, the return value may be insufficient to completely describe
the cause of the error especially during initial application
debugging.
</p>
<p>
The <code class="methodname">DB_ENV->set_errfile()</code> and <a class="xref" href="dbset_errfile.html" title="DB->set_errfile()">DB->set_errfile()</a>
methods are used to enhance the mechanism for reporting error messages to the
application by setting a C library FILE * to be used for displaying
additional Berkeley DB error messages. In some cases, when an error
occurs, Berkeley DB will output an additional error message to the
specified file reference.
</p>
<p>
Alternatively, you can use the
<a class="xref" href="envset_errcall.html" title="DB_ENV->set_errcall()">DB_ENV->set_errcall()</a> or
<a class="xref" href="dbset_errcall.html" title="DB->set_errcall()">DB->set_errcall()</a>
methods to capture the additional error information in a way that does
not use C library FILE *'s.
</p>
<p>
The error message will consist of the prefix string and a colon
("<span class="bold"><strong>:</strong></span>") (if a prefix string was
previously specified using
<a class="xref" href="dbset_errpfx.html" title="DB->set_errpfx()">DB->set_errpfx()</a> or
<a class="xref" href="envset_errpfx.html" title="DB_ENV->set_errpfx()">DB_ENV->set_errpfx()</a> ), an
error string, and a trailing <newline> character.
</p>
<p>
The default configuration when applications first create
<a class="link" href="db.html" title="Chapter 2. The DB Handle">DB</a> or
<a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a> handles is as if the
<a class="xref" href="dbset_errfile.html" title="DB->set_errfile()">DB->set_errfile()</a> or
<code class="methodname">DB_ENV->set_errfile()</code> methods were called with the standard error output
(stderr) specified as the FILE * argument. Applications wanting no
output at all can turn off this default configuration by calling the
<a class="xref" href="dbset_errfile.html" title="DB->set_errfile()">DB->set_errfile()</a> or
<code class="methodname">DB_ENV->set_errfile()</code> methods with NULL as the FILE * argument.
Additionally, explicitly configuring the error output channel using
any of the following methods will also turn off this default output for the application:
</p>
<div class="itemizedlist">
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<li>
<p>
<code class="methodname">DB_ENV->set_errfile()</code>
</p>
</li>
<li>
<p>
<a class="xref" href="dbset_errfile.html" title="DB->set_errfile()">DB->set_errfile()</a>
</p>
</li>
<li>
<p>
<a class="xref" href="envset_errcall.html" title="DB_ENV->set_errcall()">DB_ENV->set_errcall()</a>
</p>
</li>
<li>
<p>
<a class="xref" href="dbset_errcall.html" title="DB->set_errcall()">DB->set_errcall()</a>
</p>
</li>
</ul>
</div>
<p>
This error logging enhancement does not slow performance or
significantly increase application size, and may be run during normal
operation as well as during application debugging.
</p>
<p>
The <code class="methodname">DB_ENV->set_errfile()</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->set_errfile()</code> method may be called at any time during the
life of the application.
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1668956"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id1668770"></a>errfile</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>errfile</strong></span> parameter is a C library
FILE * to be used for displaying additional Berkeley DB error
information.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id1669013"></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="id1668910"></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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