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Release 5.2.28 on 6/10/2011
2011-09-13 17:44:24 +00:00
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Release 5.3.21 5/11/2012
2012-11-14 21:35:20 +00:00
<p>Library Version 11.2.5.3</p>
Release 5.2.28 on 6/10/2011
2011-09-13 17:44:24 +00:00
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Access Method Wrapup
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<p>When using the non-cursor Berkeley DB calls to retrieve key/data items under
the C/C++ APIs (for example, <a href="../api_reference/C/dbget.html" class="olink">DB-&gt;get()</a>), the memory to which the
pointer stored into the <a href="../api_reference/C/dbt.html" class="olink">DBT</a> refers is only valid until the next
call to Berkeley DB using the <a href="../api_reference/C/db.html" class="olink">DB</a> handle. (This includes <span class="bold"><strong>any</strong></span>
use of the returned <a href="../api_reference/C/db.html" class="olink">DB</a> handle, including by another thread of
control within the process. For this reason, when multiple threads are
using the returned <a href="../api_reference/C/db.html" class="olink">DB</a> handle concurrently, one of the
<a href="../api_reference/C/dbt.html#dbt_DB_DBT_MALLOC" class="olink">DB_DBT_MALLOC</a>, <a href="../api_reference/C/dbt.html#dbt_DB_DBT_REALLOC" class="olink">DB_DBT_REALLOC</a> or <a href="../api_reference/C/dbt.html#dbt_DB_DBT_USERMEM" class="olink">DB_DBT_USERMEM</a>
flags must be specified with any non-cursor <a href="../api_reference/C/dbt.html" class="olink">DBT</a> used for key or
data retrieval.)</p>
<p>When using the cursor Berkeley DB calls to retrieve key/data items under the
C/C++ APIs (for example, <a href="../api_reference/C/dbcget.html" class="olink">DBC-&gt;get()</a>), the memory to which the
pointer stored into the <a href="../api_reference/C/dbt.html" class="olink">DBT</a> refers is only valid until the next
call to Berkeley DB using the <a href="../api_reference/C/dbc.html" class="olink">DBC</a> returned by <a href="../api_reference/C/dbcursor.html" class="olink">DB-&gt;cursor()</a>.</p>
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