docs/api_reference/CXX/dbcdup.html

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  17         <p>Library Version 11.2.5.3</p>
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  21           <th colspan="3" align="center">Dbc::dup()</th>
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  24           <td width="20%" align="left"><a accesskey="p" href="dbcdel.html">Prev</a> </td>
  25           <th width="60%" align="center">Chapter 3.
  26                 The Dbc Handle
  27         </th>
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  35         <div>
  36           <div>
  37             <h2 class="title" style="clear: both"><a id="dbcdup"></a>Dbc::dup()</h2>
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  40       </div>
  41       <pre class="programlisting">#include &lt;db_cxx.h&gt;
  42
  43 int
  44 Dbc::dup(Dbc **cursorp, u_int32_t flags);</pre>
  45       <p>
  46          The <code class="methodname">Dbc::dup()</code> method creates a new cursor that uses the same
  47          transaction and locker ID as the original cursor.  This is useful when
  48          an application is using locking and requires two or more cursors in
  49          the same thread of control.
  50     </p>
  51       <p>
  52          The <code class="methodname">Dbc::dup()</code> <span>
  53
  54             <span>
  55                 method either returns a non-zero error value or throws an
  56                 exception that encapsulates a non-zero error value on
  57                 failure, and returns 0 on success.
  58             </span>
  59         </span>
  60     </p>
  61       <div class="sect2" lang="en" xml:lang="en">
  62         <div class="titlepage">
  63           <div>
  64             <div>
  65               <h3 class="title"><a id="idp819344"></a>Parameters</h3>
  66             </div>
  67           </div>
  68         </div>
  69         <div class="sect3" lang="en" xml:lang="en">
  70           <div class="titlepage">
  71             <div>
  72               <div>
  73                 <h4 class="title"><a id="idp819832"></a>cursorp</h4>
  74               </div>
  75             </div>
  76           </div>
  77           <p>
  78                   The <code class="methodname">Dbc::dup()</code> method
  79                   returns the newly created cursor in
  80                  <span class="bold"><strong>cursorp</strong></span>.
  81              </p>
  82         </div>
  83         <div class="sect3" lang="en" xml:lang="en">
  84           <div class="titlepage">
  85             <div>
  86               <div>
  87                 <h4 class="title"><a id="idp805520"></a>flags</h4>
  88               </div>
  89             </div>
  90           </div>
  91           <p>
  92                           The <span class="bold"><strong>flags</strong></span> parameter must be set to 0
  93                           or the following flag:
  94                      </p>
  95           <div class="itemizedlist">
  96             <ul type="disc">
  97               <li>
  98                 <p><a id="dup_DB_POSITION"></a>
  99                   <code class="literal">DB_POSITION</code>
 100             </p>
 101                 <p>
 102                  The newly created cursor is initialized to refer to the same position
 103                  in the database as the original cursor (if any) and hold the same
 104                  locks (if any).  If the DB_POSITION flag is not specified, or the
 105                  original cursor does not hold a database position and locks, the
 106                  created cursor is uninitialized and will behave like a cursor newly
 107                  created using the <a class="xref" href="dbcursor.html" title="Db::cursor()">Db::cursor()</a>
 108                  method.
 109             </p>
 110               </li>
 111             </ul>
 112           </div>
 113         </div>
 114       </div>
 115       <div class="sect2" lang="en" xml:lang="en">
 116         <div class="titlepage">
 117           <div>
 118             <div>
 119               <h3 class="title"><a id="idp826608"></a>Errors</h3>
 120             </div>
 121           </div>
 122         </div>
 123         <p>
 124                          The <code class="methodname">Dbc::dup()</code> <span>
 125
 126             <span>
 127                 method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a>
 128                 exception, encapsulating one of the following non-zero errors, or return one
 129                 of the following non-zero errors:
 130             </span>
 131         </span>
 132                     </p>
 133         <div class="sect3" lang="en" xml:lang="en">
 134           <div class="titlepage">
 135             <div>
 136               <div>
 137                 <h4 class="title"><a id="idp834632"></a> <span>DbRepHandleDeadException or</span> DB_REP_HANDLE_DEAD</h4>
 138               </div>
 139             </div>
 140           </div>
 141           <p>
 142                 When a client synchronizes with the master, it is possible for committed
 143                 transactions to be rolled back. This invalidates all  the database and cursor
 144                 handles opened in the replication environment. Once this occurs, an attempt to use
 145                 such a handle will
 146                 <span>
 147                     throw a <a class="xref" href="dbrephandledead.html" title="DbRepHandleDeadException">DbRepHandleDeadException</a> (if
 148                     your application is configured to throw exceptions), or
 149                 </span>
 150                 return <code class="literal">DB_REP_HANDLE_DEAD</code>.
 151                 The application will need to discard the handle and open a new one in order to
 152                 continue processing.
 153             </p>
 154         </div>
 155         <div class="sect3" lang="en" xml:lang="en">
 156           <div class="titlepage">
 157             <div>
 158               <div>
 159                 <h4 class="title"><a id="idp813280"></a><span>DbDeadlockException or </span>DB_REP_LOCKOUT</h4>
 160               </div>
 161             </div>
 162           </div>
 163           <p>
 164                 The operation was blocked by client/master synchronization.
 165             </p>
 166           <p>
 167                 <a class="xref" href="dbdeadlock.html" title="DbDeadlockException">DbDeadlockException</a> is thrown if
 168                 your Berkeley DB API is configured to throw exceptions.
 169                 Otherwise, <code class="literal">DB_REP_LOCKOUT</code> is returned.
 170             </p>
 171         </div>
 172         <div class="sect3" lang="en" xml:lang="en">
 173           <div class="titlepage">
 174             <div>
 175               <div>
 176                 <h4 class="title"><a id="idp827576"></a>EINVAL</h4>
 177               </div>
 178             </div>
 179           </div>
 180           <p>
 181                 An invalid flag value or parameter was specified.
 182             </p>
 183         </div>
 184       </div>
 185       <div class="sect2" lang="en" xml:lang="en">
 186         <div class="titlepage">
 187           <div>
 188             <div>
 189               <h3 class="title"><a id="idp829848"></a>Class</h3>
 190             </div>
 191           </div>
 192         </div>
 193         <p>
 194                 <a class="link" href="dbc.html" title="Chapter 3.  The Dbc Handle">Dbc</a>
 195             </p>
 196       </div>
 197       <div class="sect2" lang="en" xml:lang="en">
 198         <div class="titlepage">
 199           <div>
 200             <div>
 201               <h3 class="title"><a id="idp827056"></a>See Also</h3>
 202             </div>
 203           </div>
 204         </div>
 205         <p>
 206                      <a class="xref" href="dbc.html#dbclist" title="Database Cursors and Related Methods">Database Cursors and Related Methods</a>
 207                 </p>
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