title: Escaping double-quote in `delims` option of `for /F`
body: <p>I'm having a bit of trouble with a batch script which needs to parse a value out of an config file into a variable.</p>
  
  <p>Suitably anonymised, the relevant line of the file looks like </p>
  
  <pre><code>&lt;?define ProductShortName="Foo" ?&gt;
  </code></pre>
  
  <p>I want to set a variable to <code>Foo</code>. The string <code>ProductShortName</code> is unique enough to get the line with <code>findstr</code>, but then I have to extract the value. The correct approach seems to be <code>for /F</code>, but all of the following give errors:</p>
  
  <pre><code>for /F "delims=^" usebackq" %%G in (`findstr /L "ProductShortName" "%~dp0Installer\Branding.wxi"`)
  for /F "delims="" usebackq" %%G in (`findstr /L "ProductShortName" "%~dp0Installer\Branding.wxi"`)
  for /F "delims=\" usebackq" %%G in (`findstr /L "ProductShortName" "%~dp0Installer\Branding.wxi"`)
  for /F 'delims=^" usebackq' %%G in (`findstr /L "ProductShortName" "%~dp0Installer\Branding.wxi"`)
  for /F 'delims=" usebackq' %%G in (`findstr /L "ProductShortName" "%~dp0Installer\Branding.wxi"`)
  for /F "delims=" usebackq" %%G in (`findstr /L "ProductShortName" "%~dp0Installer\Branding.wxi"`)
  </code></pre>
  
  <p>mostly along the lines of</p>
  
  <pre><code>usebackq" %G in (`findstr /L "ProductShortName" "C:\foo\bar\Installer\Branding.wxi"`) was unexpected at this time.
  </code></pre>
  
  <p>What's the correct way of escaping it to split the string on <code>"</code>?</p>