 checkout.  Any byte sequence that begins with
<code>$Id:</code> and ends with <code>$</code> in the worktree file is replaced
with <code>$Id$</code> upon check-in.</p>
</div>
</div>
<div class="sect3">
<h4 id="__code_filter_code"><code>filter</code></h4>
<div class="paragraph">
<p>A <code>filter</code> attribute can be set to a string value that names a
filter driver specified in the configuration.</p>
</div>
<div class="paragraph">
<p>A filter driver consists of a <code>clean</code> command an