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<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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<th colspan="3" align="center">DB_ENV->log_get_config()</th>
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The DB_LSN Handle
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<div class="sect1" lang="en" xml:lang="en">
<div class="titlepage">
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<div>
<h2 class="title" style="clear: both"><a id="envlog_get_config"></a>DB_ENV->log_get_config()</h2>
</div>
</div>
</div>
<pre class="programlisting">#include <db.h>
int
DB_ENV->log_get_config(DB_ENV *dbenv, u_int32_t which, int *onoffp); </pre>
<p>
The <code class="methodname">DB_ENV->log_get_config()</code> method returns whether the specified
<span class="bold"><strong>which</strong></span> parameter is currently set or
not. You can manage this value using the
<a class="xref" href="envlog_set_config.html" title="DB_ENV->log_set_config()">DB_ENV->log_set_config()</a>
method.
</p>
<p>
The <code class="methodname">DB_ENV->log_get_config()</code> method may be called at any time during
the life of the application.
</p>
<p>
The <code class="methodname">DB_ENV->log_get_config()</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="idp2529736"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp2507392"></a>which</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>which</strong></span> parameter is
the message value for which configuration is being
checked. Must be set to one of the following values:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p><a id="log_get_config_DB_LOG_BLOB"></a>
<code class="literal">DB_LOG_BLOB</code>
</p>
<p>
Enables full logging of
<a class="link" href="blob.html" title="Chapter 13. Binary Large Objects">BLOB</a> data.
</p>
</li>
<li>
<p><a id="log_get_config_DB_LOG_DIRECT"></a>
<code class="literal">DB_LOG_DIRECT</code>
</p>
<p>
System buffering is turned off for Berkeley DB log
files to avoid double caching.
</p>
</li>
<li>
<p><a id="log_get_config_DB_LOG_DSYNC"></a>
<code class="literal">DB_LOG_DSYNC</code>
</p>
<p>
Berkeley DB is configured to flush log writes to the backing disk before
returning from the write system call, rather than flushing log writes
explicitly in a separate system call, as necessary.
</p>
</li>
<li>
<p><a id="log_get_config_DB_LOG_AUTO_REMOVE"></a>
<code class="literal">DB_LOG_AUTO_REMOVE</code>
</p>
<p>
Berkeley DB automatically removes log files that
are no longer needed.
</p>
</li>
<li>
<p><a id="log_get_config_DB_LOG_IN_MEMORY"></a>
<code class="literal">DB_LOG_IN_MEMORY</code>
</p>
<p>
Transaction logs are maintained in memory rather than on disk. This
means that transactions exhibit the ACI (atomicity, consistency, and
isolation) properties, but not D (durability).
</p>
</li>
<li>
<p><a id="log_get_config_DB_LOG_NOSYNC"></a>
<code class="literal">DB_LOG_NOSYNC</code>
</p>
<p>
The transaction log is not flushed from from the operating system cache to
stable storage when the logging system switches log files or a durable
transaction commits. This means that transactions exhibit the ACI
(atomicity, consistency, and isolation) properties, but only partially
support D (durability); that is, database integrity will be maintained if
the application fails and the environment is recovered, but not if the
system fails. All database files must be verified and/or restored from a
replication group master or archival backup after system failure.
</p>
</li>
<li>
<p><a id="log_get_config_DB_LOG_ZERO"></a>
<code class="literal">DB_LOG_ZERO</code>
</p>
<p>
All pages of a log file are zeroed when that log file is created.
</p>
</li>
</ul>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp2551832"></a>onoffp</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>onoffp</strong></span> parameter
references memory into which the configuration of the
specified <span class="bold"><strong>which</strong></span> parameter
is copied.
</p>
<p>
If the returned <span class="bold"><strong>onoff</strong></span>
value is zero, the parameter is off; otherwise, on.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp2552048"></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="idp2553776"></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>,
<a class="xref" href="envlog_set_config.html" title="DB_ENV->log_set_config()">DB_ENV->log_set_config()</a>
</p>
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