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<p>Library Version 11.2.5.3</p>
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<th width="60%" align="center">Appendix A. 
Berkeley DB Command Line Utilities
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<h2 class="title" style="clear: both"><a id="db_archive"></a>db_archive</h2>
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<pre class="programlisting">db_archive [-adlsVv] [-h home] [-P password] </pre>
<p>
The <span class="command"><strong>db_archive</strong></span> utility writes the pathnames of log files that are no
longer in use (for example, no longer involved in active
transactions), to the standard output, one pathname per line. These
log files should be written to backup media to provide for recovery in
the case of catastrophic failure (which also requires a snapshot of
the database files), but they may then be deleted from the system to
reclaim disk space.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
If the application(s) that use the environment make use of
any of the following methods:
</p>
<table class="simplelist" border="0" summary="Simple list">
<tr>
<td>
<a class="xref" href="envadd_data_dir.html" title="DB_ENV-&gt;add_data_dir()">DB_ENV-&gt;add_data_dir()</a>
</td>
</tr>
<tr>
<td>
<a class="xref" href="envset_data_dir.html" title="DB_ENV-&gt;set_data_dir()">DB_ENV-&gt;set_data_dir()</a>
</td>
</tr>
<tr>
<td>
<a class="xref" href="envset_lg_dir.html" title="DB_ENV-&gt;set_lg_dir()">DB_ENV-&gt;set_lg_dir()</a>
</td>
</tr>
</table>
<p>
then in order for this utility to run correctly, you need a
<a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a>
file which sets the proper paths using the
<a class="xref" href="add_data_dir_parameter.html" title="add_data_dir">add_data_dir</a>, or
<a class="xref" href="set_lg_dir_parameter.html" title="set_lg_dir">set_lg_dir</a>
configuration parameters.
</p>
</div>
<p>
The options are as follows:
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p>
<span class="bold"><strong>-a</strong></span>
</p>
<p>
Write all pathnames as absolute pathnames, instead of relative to the
database home directory.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-d</strong></span>
</p>
<p>
Remove log files that are no longer needed; no filenames are written.
This automatic log file removal is likely to make catastrophic recovery
impossible.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-h</strong></span>
</p>
<p>
Specify a home directory for the database environment; by default, the
current working directory is used.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-l</strong></span>
</p>
<p>
Write out the pathnames of all the database log files, whether or not
they are involved in active transactions.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-P</strong></span>
</p>
<p>
Specify an environment password. Although Berkeley DB utilities
overwrite password strings as soon as possible, be aware there may be
a window of vulnerability on systems where unprivileged users can see
command-line arguments or where utilities are not able to overwrite
the memory containing the command-line arguments.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-s</strong></span>
</p>
<p>
Write the pathnames of all the database files that need to be archived
in order to recover the database from catastrophic failure. If any of
the database files have not been accessed during the lifetime of the
current log files, <span class="command"><strong>db_archive</strong></span> will not include them
in this output.
</p>
<p>
It is possible that some of the files to which the log refers have
since been deleted from the system. In this case,
<span class="command"><strong>db_archive</strong></span> will ignore them. When
<a class="xref" href="db_recover.html" title="db_recover">db_recover</a>
is run, any files
to which the log refers that are not present during recovery are
assumed to have been deleted and will not be recovered.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-V</strong></span>
</p>
<p>
Write the library version number to the standard output, and exit.
</p>
</li>
<li>
<p>
<span class="bold"><strong>-v</strong></span>
</p>
<p>
Run in verbose mode.
</p>
</li>
</ul>
</div>
<p>
Log cursor handles (returned by the <a class="xref" href="logcursor.html" title="DB_ENV-&gt;log_cursor()">DB_ENV-&gt;log_cursor()</a>
method) may have open file
descriptors for log files in the database environment. Also, the Berkeley DB interfaces to
the database environment logging subsystem (for example,
<a class="xref" href="logput.html" title="DB_ENV-&gt;log_put()">DB_ENV-&gt;log_put()</a> and
<a class="xref" href="txnabort.html" title="DB_TXN-&gt;abort()">DB_TXN-&gt;abort()</a> may allocate
log cursors and have open file descriptors for log files as well. On operating systems
where filesystem related system calls (for example, rename and unlink on Windows/NT) can
fail if a process has an open file descriptor for the affected file, attempting to move or
remove the log files listed by <span class="command"><strong>db_archive</strong></span> may fail. All Berkeley DB
internal use of log cursors operates on active log files only and furthermore, is
short-lived in nature. So, an application seeing such a failure should be restructured to
close any open log cursors it may have, and otherwise to retry the operation until it
succeeds. (Although the latter is not likely to be necessary; it is hard to imagine a
reason to move or rename a log file in which transactions are being logged or aborted.)
</p>
<p>
The <span class="command"><strong>db_archive</strong></span> utility uses a Berkeley DB environment (as described
for the <span class="bold"><strong>-h</strong></span> option, the environment
variable <span class="bold"><strong>DB_HOME</strong></span>, or because the
utility was run in a directory containing a Berkeley DB environment).
In order to avoid environment corruption when using a Berkeley DB
environment, <span class="command"><strong>db_archive</strong></span> should always be given the chance to detach
from the environment and exit gracefully. To cause <span class="command"><strong>db_archive</strong></span> to
release all environment resources and exit cleanly, send it an
interrupt signal (SIGINT).
</p>
<p>
The <a class="xref" href="logarchive.html" title="DB_ENV-&gt;log_archive()">DB_ENV-&gt;log_archive()</a> method is the
underlying method used by the <span class="command"><strong>db_archive</strong></span> utility. See the
<span class="command"><strong>db_archive</strong></span> utility source code for an example of using
<code class="methodname">DB_ENV-&gt;log_archive()</code> in an IEEE/ANSI Std
1003.1 (POSIX) environment.
</p>
<p>
The <span class="command"><strong>db_archive</strong></span> utility exits 0 on success, and &gt;0 if an error
occurs.
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp63019104"></a>Environment Variables</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp63019296"></a>DB_HOME</h4>
</div>
</div>
</div>
<p>
If the <span class="bold"><strong>-h</strong></span> option is not specified and
the environment variable DB_HOME is set, it is used as the path of the
database home, as described in the
<a class="xref" href="envopen.html" title="DB_ENV-&gt;open()">DB_ENV-&gt;open()</a> method.
</p>
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Berkeley DB Command Line Utilities
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