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diff --git a/bdb/docs/ref/upgrade.3.1/put.html b/bdb/docs/ref/upgrade.3.1/put.html new file mode 100644 index 00000000000..5252b3ac00a --- /dev/null +++ b/bdb/docs/ref/upgrade.3.1/put.html @@ -0,0 +1,63 @@ +<!--$Id: put.so,v 1.8 2000/07/25 16:59:37 bostic Exp $--> +<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> +<!--All rights reserved.--> +<html> +<head> +<title>Berkeley DB Reference Guide: Release 3.1: DB->put</title> +<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> +<meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,java,C,C++"> +</head> +<body bgcolor=white> +<table><tr valign=top> +<td><h3><dl><dt>Berkeley DB Reference Guide:<dd>Upgrading Berkeley DB Applications</dl></h3></td> +<td width="1%"><a href="../../ref/upgrade.3.1/set_paniccall.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/upgrade.3.1/dup.html"><img src="../../images/next.gif" alt="Next"></a> +</td></tr></table> +<p> +<h1 align=center>Release 3.1: DB->put</h1> +<p>For the Queue and Recno access methods, when the <a href="../../api_c/db_put.html#DB_APPEND">DB_APPEND</a> flag +is specified to the <a href="../../api_c/db_put.html">DB->put</a> interface, the allocated record number +is returned to the application in the <b>key</b> <a href="../../api_c/dbt.html">DBT</a> argument. +In previous releases of Berkeley DB, this <a href="../../api_c/dbt.html">DBT</a> structure did not follow +the usual <a href="../../api_c/dbt.html">DBT</a> conventions, e.g., it was not possible to cause +Berkeley DB to allocate space for the returned record number. Rather, it was +always assumed that the <b>data</b> field of the <b>key</b> structure +referenced memory that could be used as storage for a db_recno_t type. +<p>As of the Berkeley DB 3.1.0 release, the <b>key</b> structure behaves as +described in the <a href="../../api_c/dbt.html">DBT</a> C++/Java class or C structure documentation. +<p>Applications which are using the <a href="../../api_c/db_put.html#DB_APPEND">DB_APPEND</a> flag for Queue and +Recno access method databases will require a change to upgrade to the +Berkeley DB 3.1 releases. The simplest change is likely to be to add the +<a href="../../api_c/dbt.html#DB_DBT_USERMEM">DB_DBT_USERMEM</a> flag to the <b>key</b> structure. For example, +code that appears as follows: +<p><blockquote><pre>DBT key; +db_recno_t recno; +<p> +memset(&key, 0, sizeof(DBT)); +key.data = &recno; +key.size = sizeof(recno); +DB->put(DB, NULL, &key, &data, DB_APPEND); +printf("new record number is %lu\n", (u_long)recno);</pre></blockquote> +<p>would be changed to: +<p><blockquote><pre>DBT key; +db_recno_t recno; +<p> +memset(&key, 0, sizeof(DBT)); +key.data = &recno; +key.ulen = sizeof(recno); +key.flags = DB_DBT_USERMEM; +DB->put(DB, NULL, &key, &data, DB_APPEND); +printf("new record number is %lu\n", (u_long)recno);</pre></blockquote> +<p>Note that the <b>ulen</b> field is now set as well as the flag value. +An alternative change would be: +<p><blockquote><pre>DBT key; +db_recno_t recno; +<p> +memset(&key, 0, sizeof(DBT)); +DB->put(DB, NULL, &key, &data, DB_APPEND); +recno = *(db_recno_t *)key->data; +printf("new record number is %lu\n", (u_long)recno);</pre></blockquote> +<table><tr><td><br></td><td width="1%"><a href="../../ref/upgrade.3.1/set_paniccall.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/upgrade.3.1/dup.html"><img src="../../images/next.gif" alt="Next"></a> +</td></tr></table> +<p><font size=1><a href="http://www.sleepycat.com">Copyright Sleepycat Software</a></font> +</body> +</html> |