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<H1><A NAME="SECTION008500000000000000000">
6.5 <tt class="module">statcache</tt> --
An optimization of <tt class="function">os.stat()</tt></A>
</H1>
<P>
<P>
The <tt class="module">statcache</tt> module provides a simple optimization to
<tt class="function">os.stat()</tt>: remembering the values of previous invocations.
<P>
The <tt class="module">statcache</tt> module defines the following functions:
<P>
<dl><dt><b><a name='l2h-1081'><tt class='function'>stat</tt></a></b> (<var>path</var>)
<dd>
This is the main module entry-point.
Identical for <tt class="function">os.stat()</tt>, except for remembering the result
for future invocations of the function.
</dl>
<P>
The rest of the functions are used to clear the cache, or parts of
it.
<P>
<dl><dt><b><a name='l2h-1082'><tt class='function'>reset</tt></a></b> ()
<dd>
Clear the cache: forget all results of previous <tt class="function">stat()</tt>
calls.
</dl>
<P>
<dl><dt><b><a name='l2h-1083'><tt class='function'>forget</tt></a></b> (<var>path</var>)
<dd>
Forget the result of <code>stat(<var>path</var>)</code>, if any.
</dl>
<P>
<dl><dt><b><a name='l2h-1084'><tt class='function'>forget_prefix</tt></a></b> (<var>prefix</var>)
<dd>
Forget all results of <code>stat(<var>path</var>)</code> for <var>path</var> starting
with <var>prefix</var>.
</dl>
<P>
<dl><dt><b><a name='l2h-1085'><tt class='function'>forget_dir</tt></a></b> (<var>prefix</var>)
<dd>
Forget all results of <code>stat(<var>path</var>)</code> for <var>path</var> a file in
the directory <var>prefix</var>, including <code>stat(<var>prefix</var>)</code>.
</dl>
<P>
<dl><dt><b><a name='l2h-1086'><tt class='function'>forget_except_prefix</tt></a></b> (<var>prefix</var>)
<dd>
Similar to <tt class="function">forget_prefix()</tt>, but for all <var>path</var> values
<i>not</i> starting with <var>prefix</var>.
</dl>
<P>
Example:
<P>
<dl><dd><pre class="verbatim">
>>> import os, statcache
>>> statcache.stat('.')
(16893, 2049, 772, 18, 1000, 1000, 2048, 929609777, 929609777, 929609777)
>>> os.stat('.')
(16893, 2049, 772, 18, 1000, 1000, 2048, 929609777, 929609777, 929609777)
</pre></dl>
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