libdb/docs/api_reference/C/envdbbackup.html
2012-11-14 16:35:20 -05:00

244 lines
8.7 KiB
HTML
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<?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>DB_ENV-&gt;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 DB_ENV Handle" />
<link rel="prev" href="envcreate.html" title="db_env_create" />
<link rel="next" href="envdbremove.html" title="DB_ENV-&gt;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">DB_ENV-&gt;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 DB_ENV 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>DB_ENV-&gt;dbbackup()</h2>
</div>
</div>
</div>
<pre class="programlisting">#include &lt;db.h&gt;
int
DB_ENV-&gt;dbbackup(DB_ENV *dbenv, const char *dbfile, const char *target,
u_int32_t flags); </pre>
<p>
The <code class="methodname">DB_ENV-&gt;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="DB_ENV-&gt;backup()">DB_ENV-&gt;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="DB_ENV-&gt;set_backup_callbacks()">DB_ENV-&gt;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="DB_ENV-&gt;set_backup_config()">DB_ENV-&gt;set_backup_config()</a> method.
</p>
<p>
The <code class="methodname">DB_ENV-&gt;dbbackup()</code> method may only be
called after the environment handle has been opened.
</p>
<p>
The <code class="methodname">DB_ENV-&gt;dbbackup()</code> <span>
<span>
method returns a non-zero error value on failure and 0 on success.
</span>
</span>
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp59290424"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp59302120"></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="idp59314064"></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="idp59306432"></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="idp59316512"></a>Errors</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DB_ENV-&gt;dbbackup()</code> <span>
<span>
method may fail and 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="idp59317048"></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="idp59323104"></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="idp59316216"></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="idp59312104"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>
</p>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp59324312"></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">db_env_create </td>
<td width="20%" align="center">
<a accesskey="h" href="index.html">Home</a>
</td>
<td width="40%" align="right" valign="top"> DB_ENV-&gt;dbremove()</td>
</tr>
</table>
</div>
</body>
</html>