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<title>Berkeley DB Reference Guide: Duplicating a cursor</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>Duplicating a cursor</h1>
<p>Once a cursor has been initialized (e.g., by a call to <a href="../../api_c/dbc_get.html">DBcursor->c_get</a>),
it can be thought of as identifying a particular location in a database.
The <a href="../../api_c/dbc_dup.html">DBcursor->c_dup</a> function permits an application to create a new cursor that
has the same locking and transactional information as the cursor from
which it is copied, and which optionally refers to the same position in
the database.
<p>In order to maintain a cursor position when an application is using
locking, locks are maintained on behalf of the cursor until the cursor is
closed. In cases when an application is using locking without
transactions, cursor duplication is often required to avoid
self-deadlocks. For further details, refer to
<a href="../../ref/lock/am_conv.html">Access method locking conventions</a>.
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