title: Maintain all values of duplicate keys when parsing .ini file
body: <p>I have a <code>php.ini</code> file which contains the following lines:</p>
  
  <pre><code>; ...settings
  
  extension=pdo_mysql
  extension=pdo_oci
  
  ; settings...
  </code></pre>
  
  <p>So I do this:</p>
  
  <pre><code>var_dump( parse_ini_file( '/path/to/php.ini' )[ 'extension' ] );
  </code></pre>
  
  <p>But all I get is <code>string(7) "pdo_oci"</code> so it looks like the parse simply maintains the final value which <code>extension</code> was set to.</p>
  
  <p>Is there a way to make the <code>extension</code> key return an array instead?</p>
  
  <p>I understand that PHP's internals probably use a dedicated parser to explicitly handle this situation so that extensions load properly but that does not help me achieve my goal.</p>