…which does not run

I find it annoying that the quotation marks are hardcoded in DokuWiki's source code. At the moment, I have a workaround by abusing the ACH-Template:

      <?php
        ob_start();
        tpl_content();
        $myhtml = ob_get_contents();
        ob_end_clean();
        echo wfModiOut('screen', $myhtml);
       ?>

Here wfModiOut() is a function, that consists mostly of those two lines:

      $retval = str_replace('“', '»', $retval);
      $retval = str_replace('”', '«', $retval);

I thought that a renderer plugin would replace this, and so I started to work around my workaround by the following code:

<?php
 
/**
    MODIfied RENDerer for XHTML output
    @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
    @author Werner Flamme \<w.flamme@web.de>
**/
// the following lines are stolen from the s5 plugin of Harry Fuecks and Andi Gohr
// must be run within Dokuwiki
if(!defined('DOKU_INC')) die();
 
// we inherit from the XHTML renderer instead directly of the base renderer
require_once DOKU_INC.'inc/parser/xhtml.php';
// stolen code ends here
 
if (!defined('DOKU_PLUGIN'))
  define('DOKU_PLUGIN', DOKU_INC . 'lib/plugins/');
require_once DOKU_PLUGIN . 'modirend/conf/default.php';
 
/**
    This class allow to change the double and single quotation marks,
    something I always wanted but what never got implemented.
    Instead of modifying 4 lines in DokuWikis source code
    I have to write a plugin :-(
**/
class Doku_Renderer_modirend extends Doku_Renderer_xhtml {
 
    /**
        Return some info
    **/
    function getInfo(){
        return array(
                    'author' => 'Werner Flamme',
                    'email'  => 'w.flamme@web.de',
                    'date'   => '2007-01-13',
                    'name'   => 'MODIfied RENDerer',
                    'desc'   => 'Changes quote marks',
                    'url'    => 'http://www.wernerflamme.name/users:wflamme:modirend',
                    );
    } // function getInfo
 
    /**
        add opening single quote to document's code
    **/
    function singlequoteopening()
    {
        global $conf;
        $this->doc .= $conf['modirend_sq_open'];
    }
 
    /**
        add closing single quote to document's code
    **/
    function singlequoteclosing()
    {
        global $conf;
        $this->doc .= $conf['modirend_sq_close'];
    }
 
    /**
        add opening double quote to document's code
    **/
    function doublequoteopening()
    {
        global $conf;
        $this->doc .= $conf['modirend_dq_open'];
    }
 
    /**
        add closing double quote to document's code
    **/
    function doublequoteclosing()
    {
        global $conf;
        $this->doc .= $conf['modirend_dq_close'];
    }
}
 
//Setup VIM: ex: et ts=4 enc=utf-8 :

So I use the standard XHTML renderer of DokuWiki and overwrite 4 of its methods. When I append &do=export_modirend to the URL, I get „my“ quotation marks (or when I use echo exportlink($ID, 'modirend'); inside my template). This is the theory.

Practically, the &do=export_modirend leads to displaying the document's content only, without any XHTML headers and other things that make a page look nice . Without my quotation marks. When I add some output to $conf[…], this additional Text appears.

Next, my Apache didn't show my pages correctly at all – only fragments of them were shown, whether or not I added &do=export_modirend. In the error log I only saw that Apache's child died unexpectedly (does Apache expect that the children die otherwise? )

Question: why don't I get the expected result – a text (or a page) looking exactly like the other one, except for the modified quotation marks? How can I use the renderer plugin correctly?