<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>DbEnv::set_lg_dir()</title> <link rel="stylesheet" href="apiReference.css" type="text/css" /> <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> <link rel="start" href="index.html" title="Berkeley DB C++ API Reference" /> <link rel="up" href="lsn.html" title="Chapter 8. The DbLsn Handle" /> <link rel="prev" href="envset_lg_bsize.html" title="DbEnv::set_lg_bsize()" /> <link rel="next" href="envset_lg_filemode.html" title="DbEnv::set_lg_filemode()" /> </head> <body> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">DbEnv::set_lg_dir()</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="envset_lg_bsize.html">Prev</a> </td> <th width="60%" align="center">Chapter 8. The DbLsn Handle </th> <td width="20%" align="right"> <a accesskey="n" href="envset_lg_filemode.html">Next</a></td> </tr> </table> <hr /> </div> <div class="sect1" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h2 class="title" style="clear: both"><a id="envset_lg_dir"></a>DbEnv::set_lg_dir()</h2> </div> </div> </div> <pre class="programlisting">#include <db_cxx.h> int DbEnv::set_lg_dir(const char *dir); </pre> <p> The path of a directory to be used as the location of logging files. Log files created by the Log Manager subsystem will be created in this directory. </p> <p> If no logging directory is specified, log files are created in the environment home directory. See <a href="../../programmer_reference/env_naming.html" class="olink">Berkeley DB File Naming</a> for more information. </p> <p> For the greatest degree of recoverability from system or application failure, database files and log files should be located on separate physical devices. </p> <p> The database environment's logging directory may also be configured using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. The syntax of the entry in that file is a single line with the string "set_lg_dir", one or more whitespace characters, and the directory name. Because the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read when the database environment is opened, it will silently overrule configuration done before that time. </p> <p> The <code class="methodname">DbEnv::set_lg_dir()</code> method configures operations performed using the specified <a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a> handle, not all operations performed on the underlying database environment. </p> <p> The <code class="methodname">DbEnv::set_lg_dir()</code> method may not be called after the <a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a> method is called. If the database environment already exists when <a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a> is called, the information specified to <code class="methodname">DbEnv::set_lg_dir()</code> must be consistent with the existing environment or corruption can occur. </p> <p> The <code class="methodname">DbEnv::set_lg_dir()</code> <span> <span> method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success. </span> </span> </p> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1687914"></a>Parameters</h3> </div> </div> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="id1687948"></a>dir</h4> </div> </div> </div> <p> The <span class="bold"><strong>dir</strong></span> parameter is the directory used to store the logging files. </p> <p> When using a Unicode build on Windows (the default), the <span class="bold"><strong>dir</strong></span> argument will be interpreted as a UTF-8 string, which is equivalent to ASCII for Latin characters. </p> </div> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1688101"></a>Errors</h3> </div> </div> </div> <p> The <code class="methodname">DbEnv::set_lg_dir()</code> <span> <span> method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a> exception, encapsulating one of the following non-zero errors, or return one of the following non-zero errors: </span> </span> </p> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="id1688027"></a>EINVAL</h4> </div> </div> </div> <p> If the method was called after <a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a> was called; or if an invalid flag value or parameter was specified. </p> </div> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1687942"></a>Class</h3> </div> </div> </div> <p> <a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a>, <a class="link" href="logc.html" title="The DbLogc Handle">DbLogc</a>, <a class="link" href="lsn.html" title="Chapter 8. The DbLsn Handle">DbLsn</a> </p> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1688050"></a>See Also</h3> </div> </div> </div> <p> <a class="xref" href="lsn.html#loglist" title="Logging Subsystem and Related Methods">Logging Subsystem and Related Methods</a> </p> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="envset_lg_bsize.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="lsn.html">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="envset_lg_filemode.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">DbEnv::set_lg_bsize() </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> DbEnv::set_lg_filemode()</td> </tr> </table> </div> </body> </html>