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          <div>
            <h2 class="title" style="clear: both"><a id="txncursor"></a>Transactional Cursors</h2>
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      <p>
            You can transaction-protect your cursor operations by
            specifying a transaction handle at the time that you create
            your cursor.  Beyond that, you do not ever
            provide a transaction handle directly to a cursor method.
        </p>
      <p>
            Note that if you transaction-protect a cursor, then you must
            make sure that the cursor is closed before you either commit or
            abort the transaction. For example:
        </p>
      <pre class="programlisting">#include &lt;stdio.h&gt;
#include &lt;stdlib.h&gt;

#include "db.h"

int
main(void)
{
    DBT key, data;
    DBC *cursorp;
    DB_TXN *txn = NULL;
    int ret, c_ret;
    char *replacementString = "new string";

    ...
    /* environment and db handle creation omitted */
    ...

    /* Get the txn handle */
    txn = NULL;
    ret = envp-&gt;txn_begin(envp, NULL, &amp;txn, 0);
    if (ret != 0) {
        envp-&gt;err(envp, ret, "Transaction begin failed.");
        goto err;
    }

    /* Get the cursor, supply the txn handle at that time */
    ret = dbp-&gt;cursor(dbp, txn, &amp;cursorp, 0);
    if (ret != 0) {
        envp-&gt;err(envp, ret, "Cursor open failed.");
        txn-&gt;abort(txn);
        goto err;
    }

    /* 
     * Now use the cursor. Note that we do not supply any txn handles to these
     * methods.
     */
    /* Prepare the DBTs */
    memset(&amp;key, 0, sizeof(DBT));
    memset(&amp;data, 0, sizeof(DBT));
    while (cursor-&gt;get(&amp;key, &amp;data, DB_NEXT) == 0) {
        data-&gt;data = (void *)replacementString;
        data-&gt;size = (strlen(replacementString) + 1) * sizeof(char);
        c_ret = cursor-&gt;put(cursor, &amp;key, &amp;data, DB_CURRENT);
        if (c_ret != 0) {
            /* abort the transaction and goto error */ 
            envp-&gt;err(envp, ret, "Cursor put failed.");
            cursorp-&gt;close(cursorp);
            cursorp = NULL;
            txn-&gt;abort(txn);
            goto err;
        }
    }

    /* 
     * Commit the transaction. Note that the transaction handle
     * can no longer be used.
     */ 
    ret = cursorp-&gt;close(cursorp);
    if (ret != 0) {
        envp-&gt;err(envp, ret, "Cursor close failed.");
        txn-&gt;abort(txn);
        goto err;
    }
    ret = txn-&gt;commit(txn, 0);
    if (ret != 0) {
        envp-&gt;err(envp, ret, "Transaction commit failed.");
        goto err;
    }

err:
    /* Close the cursor (if the handle is not NULL)
     * and perform whatever other cleanup is required */

    /* Close the database */

    /* Close the environment */

    ...

    if (c_ret != 0)
        ret = c_ret;
    
    return (ret == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
} </pre>
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