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<b>Db::set_error_stream</b>
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<b><pre>
#include <db_cxx.h>
<p>
void Db::set_error_stream(class ostream*);
</pre></b>
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<b>Description: Db::set_error_stream</b>
<p>When an error occurs in the Berkeley DB library, an exception is thrown or an
<b>errno</b> value is returned by the interface. In some cases,
however, the <b>errno</b> value may be insufficient to completely
describe the cause of the error, especially during initial application
debugging.</p>
<p>The <a href="../api_cxx/env_set_error_stream.html">DbEnv::set_error_stream</a> and Db::set_error_stream methods
are used to enhance the mechanism for reporting error messages to the
application by setting the C++ ostream 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 stream.</p>
<p>The error message will consist of the prefix string and a colon
("<b>:</b>") (if a prefix string was previously specified using
<a href="../api_cxx/env_set_errpfx.html">DbEnv::set_errpfx</a>), an error string, and a trailing
<newline> character.</p>
<p>Setting <b>stream</b> to NULL unconfigures the interface.</p>
<p>Alternatively, you can use the <a href="../api_cxx/env_set_errfile.html">DbEnv::set_errfile</a> and
<a href="../api_cxx/db_set_errfile.html">Db::set_errfile</a> methods to display the additional information via a C
library FILE *, or the <a href="../api_cxx/env_set_errcall.html">DbEnv::set_errcall</a> and
<a href="../api_cxx/db_set_errcall.html">Db::set_errcall</a> methods to capture the additional error information
in a way that does not use either output streams or C library FILE *'s.
You should not mix these approaches.</p>
<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>For <a href="../api_cxx/db_class.html">Db</a> handles opened inside of Berkeley DB environments, calling the
Db::set_error_stream method affects the entire environment and is equivalent to calling
the <a href="../api_cxx/env_set_error_stream.html">DbEnv::set_error_stream</a> method.</p>
<p>The Db::set_error_stream method configures operations performed using the specified
<a href="../api_cxx/db_class.html">Db</a> handle, not all operations performed on the underlying
database.</p>
<p>The Db::set_error_stream method may be called at any time during the life of the
application.</p>
<b>Parameters</b> <br>
<b>stream</b><ul compact><li>The <b>stream</b> parameter is the application-specified output stream to
be used for additional error information.</ul>
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<br><b>Class</b>
<a href="../api_cxx/db_class.html">Db</a>
<br><b>See Also</b>
<a href="../api_cxx/db_list.html">Databases and Related Methods</a>
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