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<title>Berkeley DB Reference Guide: Retrieved key/data permanence for C/C++</title>
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<td><h3><dl><dt>Berkeley DB Reference Guide:<dd>Access Methods</dl></h3></td>
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<h1 align=center>Retrieved key/data permanence for C/C++</h1>
<p>When using the non-cursor Berkeley DB calls to retrieve key/data items under
the C/C++ APIs (for example, <a href="../../api_c/db_get.html">DB->get</a>), the memory to which the
pointer stored into the <a href="../../api_c/dbt_class.html">DBT</a> refers is only valid until the next
call to Berkeley DB using the <a href="../../api_c/db_class.html">DB</a> handle. (This includes <b>any</b>
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<a href="../../api_c/dbt_class.html#DB_DBT_MALLOC">DB_DBT_MALLOC</a>, <a href="../../api_c/dbt_class.html#DB_DBT_REALLOC">DB_DBT_REALLOC</a> or <a href="../../api_c/dbt_class.html#DB_DBT_USERMEM">DB_DBT_USERMEM</a>
flags must be specified with any non-cursor <a href="../../api_c/dbt_class.html">DBT</a> used for key or
data retrieval.)
<p>When using the cursor Berkeley DB calls to retrieve key/data items under the
C/C++ APIs (for example, <a href="../../api_c/dbc_get.html">DBcursor->c_get</a>), the memory to which the
pointer stored into the <a href="../../api_c/dbt_class.html">DBT</a> refers is only valid until the next
call to Berkeley DB using the <a href="../../api_c/dbc_class.html">DBC</a> handle returned by <a href="../../api_c/db_cursor.html">DB->cursor</a>.
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