1<!--$Id: env_lsn_reset.so,v 1.4 2005/12/13 16:48:01 bostic Exp $--> 2<!--Copyright (c) 1997,2008 Oracle. All rights reserved.--> 3<!--See the file LICENSE for redistribution information.--> 4<html> 5<head> 6<title>Berkeley DB: DB_ENV->lsn_reset</title> 7<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> 8<meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> 9</head> 10<body bgcolor=white> 11<table width="100%"><tr valign=top> 12<td> 13<b>DB_ENV->lsn_reset</b> 14</td> 15<td align=right> 16<a href="/api_c/api_core.html"><img src="/images/api.gif" alt="API"></a> 17<a href="/ref/toc.html"><img src="/images/ref.gif" alt="Ref"></a></td> 18</tr></table> 19<hr size=1 noshade> 20<tt> 21<b><pre> 22#include <db.h> 23<p> 24int 25DB_ENV->lsn_reset(DB_ENV *dbenv, const char *file, u_int32_t flags); 26</pre></b> 27<hr size=1 noshade> 28<b>Description: DB_ENV->lsn_reset</b> 29<p>The DB_ENV->lsn_reset method allows database files to be moved from one 30transactional database environment to another.</p> 31<p>Database pages in transactional database environments contain references 32to the environment's log files (that is, log sequence numbers, or LSNs). 33Copying or moving a database file from one database environment to 34another, and then modifying it, can result in data corruption if the 35LSNs are not first cleared.</p> 36<p>Note that LSNs should be reset before moving or copying the database 37file into a new database environment, rather than moving or copying the 38database file and then resetting the LSNs. Berkeley DB has consistency checks 39that may be triggered if an application calls DB_ENV->lsn_reset 40on a database in a new environment when the database LSNs still reflect 41the old environment.</p> 42<p>The DB_ENV->lsn_reset method modifies the physical file, in-place. 43Applications should not reset LSNs in files that are currently in use.</p> 44<p>The DB_ENV->lsn_reset method may be called at any time during the life of the 45application.</p> 46<p>The DB_ENV->lsn_reset method 47returns a non-zero error value on failure 48and 0 on success. 49</p> 50<b>Parameters</b> <br> 51 <b>file</b><ul compact><li>The name of the physical file in which the LSNs are to be cleared.</ul> 52 <b>flags</b><ul compact><li>The <b>flags</b> parameter must be set to 0 or 53the following value: 54<br> 55<b>DB_ENCRYPT</b><ul compact><li>The file contains encrypted databases.</ul> 56<br></ul> 57<br> 58<br><b>Errors</b> 59<p>The DB_ENV->lsn_reset method 60may fail and return one of the following non-zero errors:</p> 61<br> 62<b>EINVAL</b><ul compact><li>An 63invalid flag value or parameter was specified.</ul> 64<br> 65<hr size=1 noshade> 66<br><b>Class</b> 67<a href="/api_c/env_class.html">DB_ENV</a> 68<br><b>See Also</b> 69<a href="/api_c/env_list.html">Database Environments and Related Methods</a> 70</tt> 71<table width="100%"><tr><td><br></td><td align=right> 72<a href="/api_c/api_core.html"><img src="/images/api.gif" alt="API"></a><a href="/ref/toc.html"><img src="/images/ref.gif" alt="Ref"></a> 73</td></tr></table> 74<p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> 75</body> 76</html> 77
