mirror of
https://github.com/berkeleydb/libdb.git
synced 2024-11-16 17:16:25 +00:00
335 lines
14 KiB
HTML
335 lines
14 KiB
HTML
<?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->set_backup_callbacks()</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="envset_app_dispatch.html" title="DB_ENV->set_app_dispatch()" />
|
||
<link rel="next" href="envset_backup_config.html" title="DB_ENV->set_backup_config()" />
|
||
</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->set_backup_callbacks()</th>
|
||
</tr>
|
||
<tr>
|
||
<td width="20%" align="left"><a accesskey="p" href="envset_app_dispatch.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="envset_backup_config.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_backup_callbacks"></a>DB_ENV->set_backup_callbacks()</h2>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<pre class="programlisting">#include <db.h>
|
||
|
||
DB_ENV->set_backup_callbacks(DB_ENV,
|
||
int (*open_func)(DB_ENV *, const char *dbname,
|
||
const char *target, void **handle),
|
||
int (*write_func)(DB_ENV *, u_int32_t offset_gbytes,
|
||
u_int32_t offset_bytes, u_int32_t size,
|
||
u_int8_t *buf, void *handle),
|
||
int (*close_func)(DB_ENV *, const char *dbname, void *handle)); </pre>
|
||
<p>
|
||
The <code class="methodname">DB_ENV->set_backup_callbacks()</code> method
|
||
configures three callback functions which can be used by the
|
||
<a class="xref" href="envbackup.html" title="DB_ENV->backup()">DB_ENV->backup()</a>
|
||
or
|
||
<a class="xref" href="envdbbackup.html" title="DB_ENV->dbbackup()">DB_ENV->dbbackup()</a>
|
||
methods to override their default behavior. If one callback is
|
||
configured, then all three callbacks must be configured.
|
||
These callbacks are required if the <code class="literal">target</code> parameter is
|
||
set to <code class="literal">NULL</code> for the
|
||
<a class="xref" href="envbackup.html" title="DB_ENV->backup()">DB_ENV->backup()</a>
|
||
or
|
||
<a class="xref" href="envdbbackup.html" title="DB_ENV->dbbackup()">DB_ENV->dbbackup()</a>
|
||
methods.
|
||
</p>
|
||
<p>
|
||
The <code class="methodname">DB_ENV->set_backup_callbacks()</code> method
|
||
configures operations performed using the specified
|
||
<a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a> handle, not all operations
|
||
performed on the underlying database environment.
|
||
</p>
|
||
<p>
|
||
The <code class="methodname">DB_ENV->set_backup_callbacks()</code> method may
|
||
be called at any time during the life of the application.
|
||
</p>
|
||
<p>
|
||
The <code class="methodname">DB_ENV->set_backup_callbacks()</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="idp59780936"></a>Parameters</h3>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<div class="sect3" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h4 class="title"><a id="idp59783128"></a>open_func</h4>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
The <span class="bold"><strong>open_func</strong></span> parameter
|
||
is the function used when a target location is opened
|
||
during a backup. This function should do whatever is
|
||
necessary to prepare the backup destination for
|
||
writing the data.
|
||
</p>
|
||
<p>
|
||
This function takes four parameters:
|
||
</p>
|
||
<div class="itemizedlist">
|
||
<ul type="disc">
|
||
<li>
|
||
<p>
|
||
<code class="literal">dbenv</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>dbenv</strong></span>
|
||
parameter is the enclosing database environment
|
||
handle.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p>
|
||
<code class="literal">dbname</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>dbname</strong></span> parameter is the
|
||
name of the database being backed up.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p>
|
||
<code class="literal">target</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>target</strong></span> parameter is the
|
||
backup's directory destination.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p>
|
||
<code class="literal">handle</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>handle</strong></span> parameter references
|
||
the handle (usually a file handle) to which the backup will be
|
||
written.
|
||
</p>
|
||
</li>
|
||
</ul>
|
||
</div>
|
||
</div>
|
||
<div class="sect3" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h4 class="title"><a id="idp59779736"></a>write_func</h4>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
The <span class="bold"><strong>write_func</strong></span> parameter
|
||
is the function used to write data during a backup.
|
||
The function takes six parameters:
|
||
</p>
|
||
<div class="itemizedlist">
|
||
<ul type="disc">
|
||
<li>
|
||
<p>
|
||
<code class="literal">dbenv</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>dbenv</strong></span>
|
||
parameter is the enclosing database environment
|
||
handle.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p>
|
||
<code class="literal">offset_gbytes</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>offset_gbytes</strong></span>
|
||
parameter specifies the number of gigabytes into
|
||
the output handle where the data can should be
|
||
written. This value, plus the value specified on
|
||
<code class="literal">offset_bytes</code>, indicates the
|
||
offset within the output handle where the backup
|
||
should begin.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p>
|
||
<code class="literal">offset_bytes</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>offset_bytes</strong></span>
|
||
parameter specifies the number of bytes into the
|
||
output handle where the data can be located. This
|
||
value, plus the value specified on
|
||
<code class="literal">offset_gbytes</code>, indicates the
|
||
offset within the output handle where the backup
|
||
should begin.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p>
|
||
<code class="literal">size</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>size</strong></span>
|
||
parameter specifies the number of bytes to back up
|
||
from the buffer.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p>
|
||
<code class="literal">buf</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>buf</strong></span>
|
||
parameter is the buffer which contains the data to
|
||
be backed up.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p>
|
||
<code class="literal">handle</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>handle</strong></span>
|
||
parameter references the handle (usually a file
|
||
handle) to which the backup will be written.
|
||
</p>
|
||
</li>
|
||
</ul>
|
||
</div>
|
||
</div>
|
||
<div class="sect3" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h4 class="title"><a id="idp59784136"></a>close_func</h4>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<p>
|
||
The <span class="bold"><strong>close_func</strong></span> parameter
|
||
is the function used when ending a backup and closing a
|
||
backup target. The function takes three parameters:
|
||
</p>
|
||
<div class="itemizedlist">
|
||
<ul type="disc">
|
||
<li>
|
||
<p>
|
||
<code class="literal">dbenv</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>dbenv</strong></span>
|
||
parameter is the enclosing database environment
|
||
handle.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p>
|
||
<code class="literal">dbname</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>dbname</strong></span> parameter is the
|
||
name of the database that has now been backed up.
|
||
</p>
|
||
</li>
|
||
<li>
|
||
<p>
|
||
<code class="literal">handle</code>
|
||
</p>
|
||
<p>
|
||
The <span class="bold"><strong>handle</strong></span>
|
||
parameter references the handle (usually a file
|
||
handle) to which the backup was written, and which
|
||
now must be closed or otherwise discarded.
|
||
</p>
|
||
</li>
|
||
</ul>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
<div class="sect2" lang="en" xml:lang="en">
|
||
<div class="titlepage">
|
||
<div>
|
||
<div>
|
||
<h3 class="title"><a id="idp59817320"></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="idp59801544"></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>,
|
||
<a class="xref" href="envget_backup_callbacks.html" title="DB_ENV->get_backup_callbacks()">DB_ENV->get_backup_callbacks()</a>,
|
||
<a class="xref" href="envbackup.html" title="DB_ENV->backup()">DB_ENV->backup()</a>, and
|
||
<a class="xref" href="envdbbackup.html" title="DB_ENV->dbbackup()">DB_ENV->dbbackup()</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_app_dispatch.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="envset_backup_config.html">Next</a></td>
|
||
</tr>
|
||
<tr>
|
||
<td width="40%" align="left" valign="top">DB_ENV->set_app_dispatch() </td>
|
||
<td width="20%" align="center">
|
||
<a accesskey="h" href="index.html">Home</a>
|
||
</td>
|
||
<td width="40%" align="right" valign="top"> DB_ENV->set_backup_config()</td>
|
||
</tr>
|
||
</table>
|
||
</div>
|
||
</body>
|
||
</html>
|