title: Improve Windows's batch script performance
body: <p>I want to delete specific lines from text files, using this command:</p>
  
  <pre><code>for /f "delims=" %%d in ('"dir &lt;Dir_Path&gt; /a /b /s | sort"') do type %%d | findstr /V &lt;String_To_Delete&gt;  &gt;  &lt;%%d_Filtered.txt&gt;
  </code></pre>
  
  <p>It is working but very very slow.
  How can I improve the command or make it use in multi  cores?</p>