<?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::dbbackup()</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="env.html" title="Chapter 5. The DbEnv Handle" /> <link rel="prev" href="envcreate.html" title="DbEnv" /> <link rel="next" href="envdbremove.html" title="DbEnv::dbremove()" /> </head> <body> <div xmlns="" class="navheader"> <div class="libver"> <p>Library Version 11.2.5.3</p> </div> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">DbEnv::dbbackup()</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="envcreate.html">Prev</a> </td> <th width="60%" align="center">Chapter 5. The DbEnv Handle </th> <td width="20%" align="right"> <a accesskey="n" href="envdbremove.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="envdbbackup"></a>DbEnv::dbbackup()</h2> </div> </div> </div> <pre class="programlisting">#include <db_cxx.h> int DbEnv::dbbackup(const char *dbfile, const char *target, u_int32_t flags);</pre> <p> The <code class="methodname">DbEnv::dbbackup()</code> method performs a hot backup of a single database file contained within the environment. </p> <p> To back up an entire environment, use the <a class="xref" href="envbackup.html" title="DbEnv::backup()">DbEnv::backup()</a> method. </p> <p> This method's default behavior can be changed by setting backup callbacks. See <a class="xref" href="envset_backup_callbacks.html" title="DbEnv::set_backup_callbacks()">DbEnv::set_backup_callbacks()</a> for more information. Additional tuning parameters can also be set using the <a class="xref" href="envset_backup_config.html" title="DbEnv::set_backup_config()">DbEnv::set_backup_config()</a> method. </p> <p> The <code class="methodname">DbEnv::dbbackup()</code> method may only be called after the environment handle has been opened. </p> <p> The <code class="methodname">DbEnv::dbbackup()</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="idp6651504"></a>Parameters</h3> </div> </div> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="idp6652104"></a>dbfile</h4> </div> </div> </div> <p> Identifies the database file that you want to back up. </p> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="idp6666272"></a>target</h4> </div> </div> </div> <p> Identifies the directory in which the back up will be placed. This target must exist; otherwise this method exits with an <code class="literal">ENOENT</code> error return. </p> <p> Note that if the backup callbacks are set, then the value specified to this parameter is passed on to the <code class="literal">open_func()</code> callback. If this parameter is NULL, then the target must be specified directly to the <code class="literal">open_func()</code> callback. </p> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="idp6658880"></a>flags</h4> </div> </div> </div> <p> The <span class="bold"><strong>flags</strong></span> parameter must be set to 0 or the following value: </p> <div class="itemizedlist"> <ul type="disc"> <li> <p> <code class="literal">DB_EXCL</code> </p> <p> Return an <code class="literal">EEXIST</code> error if a target backup file already exists. </p> </li> </ul> </div> </div> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="idp6668720"></a>Errors</h3> </div> </div> </div> <p> The <code class="methodname">DbEnv::dbbackup()</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="idp6677600"></a>EEXIST</h4> </div> </div> </div> <p> <code class="literal">DB_EXCL</code> was specified for the <code class="literal">flags</code> parameter, and an existing target file was discovered when attempting to back up a source file. </p> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="idp6673584"></a>ENOENT</h4> </div> </div> </div> <p> The target directory does not exist. </p> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="idp6677816"></a>EINVAL</h4> </div> </div> </div> <p> 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="idp6643488"></a>Class</h3> </div> </div> </div> <p> <a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a> </p> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="idp6644328"></a>See Also</h3> </div> </div> </div> <p> <a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments 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="envcreate.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="env.html">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="envdbremove.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">DbEnv </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> DbEnv::dbremove()</td> </tr> </table> </div> </body> </html>