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<h2 class="title" style="clear: both"><a id="upgrade_4_3_enomem"></a>ENOMEM and DbMemoryException</h2>
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<p>In versions of Berkeley DB before 4.3, the error <span class="bold"><strong>ENOMEM</strong></span> was used to
indicate that the buffer in a <a href="../api_reference/C/dbt.html" class="olink">DBT</a> configured with
<a href="../api_reference/C/dbt.html#dbt_DB_DBT_USERMEM" class="olink">DB_DBT_USERMEM</a> was too small to hold a key or data item being
retrieved. The 4.3 release adds a new error, <code class="literal">DB_BUFFER_SMALL</code>,
that is returned in this case.</p>
<p>The reason for the change is that the use of <span class="bold"><strong>ENOMEM</strong></span> was
ambiguous: calls such as <a href="../api_reference/C/dbget.html" class="olink">DB->get()</a> or <a href="../api_reference/C/dbcget.html" class="olink">DBC->get()</a> could return
<span class="bold"><strong>ENOMEM</strong></span> either if a <a href="../api_reference/C/dbt.html" class="olink">DBT</a> was too small or if some resource
was exhausted.</p>
<p>The result is that starting with the 4.3 release, C applications should
always treat <span class="bold"><strong>ENOMEM</strong></span> as a fatal error. Code that checked for
the <span class="bold"><strong>ENOMEM</strong></span> return and allocated a new buffer should be changed
to check for <code class="literal">DB_BUFFER_SMALL</code>.</p>
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In C++ applications configured for exceptions, a
<a href="../api_reference/CXX/dbmemory.html" class="olink">DbMemoryException</a>
will continue to be thrown in both cases, and applications should check
the errno in the exception to determine which error occurred.
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<p>In Java applications, a <span class="bold"><strong>DbMemoryException</strong></span> will be thrown when a <span class="bold"><strong>Dbt</strong></span> is too small to hold a return value, and an <span class="bold"><strong>OutOfMemoryError</strong></span> will be thrown in all cases of resource exhaustion.</p>
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