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>Release 3.2: DB callback functions, app_private field</title> 7 <link rel="stylesheet" href="gettingStarted.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 Programmer's Reference Guide" /> 10 <link rel="up" href="upgrade_3_2_toc.html" title="Chapter��35.��Upgrading Berkeley DB 3.1 applications to Berkeley DB 3.2" /> 11 <link rel="prev" href="upgrade_3_2_set_flags.html" title="Release 3.2: DB_ENV->set_flags" /> 12 <link rel="next" href="upgrade_3_2_renumber.html" title="Release 3.2: Logically renumbering records" /> 13 </head> 14 <body> 15 <div class="navheader"> 16 <table width="100%" summary="Navigation header"> 17 <tr> 18 <th colspan="3" align="center">Release 3.2: DB callback functions, app_private field</th> 19 </tr> 20 <tr> 21 <td width="20%" align="left"><a accesskey="p" href="upgrade_3_2_set_flags.html">Prev</a>��</td> 22 <th width="60%" align="center">Chapter��35.��Upgrading Berkeley DB 3.1 applications to Berkeley DB 3.2</th> 23 <td width="20%" align="right">��<a accesskey="n" href="upgrade_3_2_renumber.html">Next</a></td> 24 </tr> 25 </table> 26 <hr /> 27 </div> 28 <div class="sect1" lang="en" xml:lang="en"> 29 <div class="titlepage"> 30 <div> 31 <div> 32 <h2 class="title" style="clear: both"><a id="upgrade_3_2_callback"></a>Release 3.2: DB callback functions, app_private field</h2> 33 </div> 34 </div> 35 </div> 36 <p>In the Berkeley DB 3.2 release, four application callback functions (the 37callback functions set by <a href="../api_reference/C/dbset_bt_compare.html" class="olink">DB->set_bt_compare()</a>, 38<a href="../api_reference/C/dbset_bt_prefix.html" class="olink">DB->set_bt_prefix()</a>, <a href="../api_reference/C/dbset_dup_compare.html" class="olink">DB->set_dup_compare()</a> and 39<a href="../api_reference/C/dbset_h_hash.html" class="olink">DB->set_h_hash()</a>) were modified to take a reference to a 40<a href="../api_reference/C/db.html" class="olink">DB</a> object as their first argument. This change allows the Berkeley DB 41Java API to reasonably support these interfaces. There is currently no 42need for the callback functions to do anything with this additional 43argument.</p> 44 <p>C and C++ applications that specify their own Btree key comparison, 45Btree prefix comparison, duplicate data item comparison or Hash 46functions should modify these functions to take a reference to a 47<a href="../api_reference/C/db.html" class="olink">DB</a> structure as their first argument. No further change is 48required.</p> 49 <p>The app_private field of the <a href="../api_reference/C/dbt.html" class="olink">DBT</a> structure (accessible only from 50the Berkeley DB C API) has been removed in the 3.2 release. It was replaced 51with app_private fields in the <a href="../api_reference/C/env.html" class="olink">DB_ENV</a> handles. 52Applications using this field will have to convert to using one of the 53replacement fields.</p> 54 </div> 55 <div class="navfooter"> 56 <hr /> 57 <table width="100%" summary="Navigation footer"> 58 <tr> 59 <td width="40%" align="left"><a accesskey="p" href="upgrade_3_2_set_flags.html">Prev</a>��</td> 60 <td width="20%" align="center"> 61 <a accesskey="u" href="upgrade_3_2_toc.html">Up</a> 62 </td> 63 <td width="40%" align="right">��<a accesskey="n" href="upgrade_3_2_renumber.html">Next</a></td> 64 </tr> 65 <tr> 66 <td width="40%" align="left" valign="top">Release 3.2: DB_ENV->set_flags��</td> 67 <td width="20%" align="center"> 68 <a accesskey="h" href="index.html">Home</a> 69 </td> 70 <td width="40%" align="right" valign="top">��Release 3.2: Logically renumbering records</td> 71 </tr> 72 </table> 73 </div> 74 </body> 75</html> 76