1<?xml version="1.0" encoding="UTF-8" standalone="no"?> 2<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 3<html xmlns="http://www.w3.org/1999/xhtml"> 4 <head> 5 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> 6 <title>DB_ENV->cdsgroup_begin()</title> 7 <link rel="stylesheet" href="apiReference.css" type="text/css" /> 8 <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> 9 <link rel="start" href="index.html" title="Berkeley DB C API Reference" /> 10 <link rel="up" href="txn.html" title="Chapter 12. The DB_TXN Handle" /> 11 <link rel="prev" href="dbget_transactional.html" title="DB->get_transactional()" /> 12 <link rel="next" href="envget_tx_max.html" title="DB_ENV->get_tx_max()" /> 13 </head> 14 <body> 15 <div class="navheader"> 16 <table width="100%" summary="Navigation header"> 17 <tr> 18 <th colspan="3" align="center">DB_ENV->cdsgroup_begin()</th> 19 </tr> 20 <tr> 21 <td width="20%" align="left"><a accesskey="p" href="dbget_transactional.html">Prev</a> </td> 22 <th width="60%" align="center">Chapter 12. 23 The DB_TXN Handle 24 </th> 25 <td width="20%" align="right"> <a accesskey="n" href="envget_tx_max.html">Next</a></td> 26 </tr> 27 </table> 28 <hr /> 29 </div> 30 <div class="sect1" lang="en" xml:lang="en"> 31 <div class="titlepage"> 32 <div> 33 <div> 34 <h2 class="title" style="clear: both"><a id="envcdsgroup_begin"></a>DB_ENV->cdsgroup_begin()</h2> 35 </div> 36 </div> 37 </div> 38 <pre class="programlisting">#include <db.h> 39 40int 41DB_ENV->cdsgroup_begin(DB_ENV *dbenv, DB_TXN **tid); </pre> 42 <p> 43 The <code class="methodname">DB_ENV->cdsgroup_begin()</code> method allocates a locker ID in an 44 environment configured for Berkeley DB Concurrent Data Store 45 applications. It copies a pointer to a 46 <a class="link" href="txn.html" title="Chapter 12. The DB_TXN Handle">DB_TXN</a> that uniquely identifies 47 the locker ID into the memory to which <span class="bold"><strong>tid</strong></span> refers. 48 Calling the 49 <a class="xref" href="txncommit.html" title="DB_TXN->commit()">DB_TXN->commit()</a> method will 50 discard the allocated locker ID. 51 </p> 52 <p> 53 See <a href="../../programmer_reference/cam.html#cam_intro" class="olink">Berkeley DB Concurrent Data Store applications</a> for more information about when this is 54 required. 55 </p> 56 <p> 57 The <code class="methodname">DB_ENV->cdsgroup_begin()</code> method may be called at any time during 58 the life of the application. 59 </p> 60 <p> 61 The <code class="methodname">DB_ENV->cdsgroup_begin()</code> <span> 62 <span> 63 method returns a non-zero error value on failure and 0 on success. 64 </span> 65 66 </span> 67 </p> 68 <div class="sect2" lang="en" xml:lang="en"> 69 <div class="titlepage"> 70 <div> 71 <div> 72 <h3 class="title"><a id="id1707449"></a>Errors</h3> 73 </div> 74 </div> 75 </div> 76 <p> 77 The <code class="methodname">DB_ENV->cdsgroup_begin()</code> <span> 78 <span> 79 method may fail and return one of the following non-zero errors: 80 </span> 81 82 </span> 83 </p> 84 <div class="sect3" lang="en" xml:lang="en"> 85 <div class="titlepage"> 86 <div> 87 <div> 88 <h4 class="title"><a id="id1707248"></a>ENOMEM</h4> 89 </div> 90 </div> 91 </div> 92 <p> 93 The maximum number of lockers has been reached. 94 </p> 95 </div> 96 </div> 97 <div class="sect2" lang="en" xml:lang="en"> 98 <div class="titlepage"> 99 <div> 100 <div> 101 <h3 class="title"><a id="id1707450"></a>Class</h3> 102 </div> 103 </div> 104 </div> 105 <p> 106 <a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a>, <a class="link" href="txn.html" title="Chapter 12. The DB_TXN Handle">DB_TXN</a> 107 </p> 108 </div> 109 <div class="sect2" lang="en" xml:lang="en"> 110 <div class="titlepage"> 111 <div> 112 <div> 113 <h3 class="title"><a id="id1707510"></a>See Also</h3> 114 </div> 115 </div> 116 </div> 117 <p> 118 <a class="xref" href="txn.html#txnlist" title="Transaction Subsystem and Related Methods">Transaction Subsystem and Related Methods</a> 119 </p> 120 </div> 121 </div> 122 <div class="navfooter"> 123 <hr /> 124 <table width="100%" summary="Navigation footer"> 125 <tr> 126 <td width="40%" align="left"><a accesskey="p" href="dbget_transactional.html">Prev</a> </td> 127 <td width="20%" align="center"> 128 <a accesskey="u" href="txn.html">Up</a> 129 </td> 130 <td width="40%" align="right"> <a accesskey="n" href="envget_tx_max.html">Next</a></td> 131 </tr> 132 <tr> 133 <td width="40%" align="left" valign="top">DB->get_transactional() </td> 134 <td width="20%" align="center"> 135 <a accesskey="h" href="index.html">Home</a> 136 </td> 137 <td width="40%" align="right" valign="top"> DB_ENV->get_tx_max()</td> 138 </tr> 139 </table> 140 </div> 141 </body> 142</html> 143