<!--$Id: log_file.so,v 10.34 2004/08/13 03:38:57 bostic Exp $--> <!--Copyright (c) 1997,2008 Oracle. All rights reserved.--> <!--See the file LICENSE for redistribution information.--> <html> <head> <title>Berkeley DB: DB_ENV->log_file</title> <meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> <meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> </head> <body bgcolor=white> <table width="100%"><tr valign=top> <td> <b>DB_ENV->log_file</b> </td> <td align=right> <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></td> </tr></table> <hr size=1 noshade> <tt> <b><pre> #include <db.h> <p> int DB_ENV->log_file(DB_ENV *env, const DB_LSN *lsn, char *namep, size_t len); </pre></b> <hr size=1 noshade> <b>Description: DB_ENV->log_file</b> <p>The DB_ENV->log_file method maps DB_LSN structures to filenames, returning the name of the file containing the record named by <b>lsn</b>.</p> <p>This mapping of DB_LSN structures to files is needed for database administration. For example, a transaction manager typically records the earliest <a href="../api_c/lsn_class.html">DB_LSN</a> needed for restart, and the database administrator may want to archive log files to tape when they contain only <a href="../api_c/lsn_class.html">DB_LSN</a> entries before the earliest one needed for restart.</p> <p>The DB_ENV->log_file method returns a non-zero error value on failure and 0 on success. </p> <b>Parameters</b> <br> <b>lsn</b><ul compact><li>The <b>lsn</b> parameter is the DB_LSN structure for which a filename is wanted.</ul> <b>namep</b><ul compact><li>The <b>namep</b> parameter references memory into which the name of the file containing the record named by <b>lsn</b> is copied.</ul> <b>len</b><ul compact><li>The <b>len</b> parameter is the length of the <b>namep</b> buffer in bytes. If <b>namep</b> is too short to hold the filename, DB_ENV->log_file will fail. (Log filenames are normally quite short, on the order of 10 characters.)</ul> <br> <br><b>Errors</b> <p>The DB_ENV->log_file method may fail and return one of the following non-zero errors:</p> <br> <b>EINVAL</b><ul compact><li>If supplied buffer was too small to hold the log filename; or if an invalid flag value or parameter was specified.</ul> <br> <hr size=1 noshade> <br><b>Class</b> <a href="../api_c/env_class.html">DB_ENV</a>, <a href="../api_c/logc_class.html">DB_LOGC</a>, <a href="../api_c/lsn_class.html">DB_LSN</a> <br><b>See Also</b> <a href="../api_c/log_list.html">Logging Subsystem and Related Methods</a> </tt> <table width="100%"><tr><td><br></td><td align=right> <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> </td></tr></table> <p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> </body> </html>