public function getApacheInstancesPath()
    {
        if ($this->apache_config_path === false &&
            is_array($this->apache_compiles) &&
            array_key_exists('SERVER_CONFIG_FILE', $this->apache_compiles)
        ) {
            $config_file = $this->apache_compiles['SERVER_CONFIG_FILE'];
            if (is_file($config_file)) {
                $base_path = dirname($config_file);
                if (is_dir($base_path . DIRECTORY_SEPARATOR . 'other')) {
                    $this->apache_config_path = $base_path . DIRECTORY_SEPARATOR . 'other';
                } elseif (is_dir($base_path . DIRECTORY_SEPARATOR . 'conf.d')) {
                    $this->apache_config_path = $base_path . DIRECTORY_SEPARATOR . 'conf.d';
                }
            }  elseif (array_key_exists('HTTPD_ROOT', $this->apache_compiles)) {
                $base_path = preg_replace('/"$/', '', preg_replace('/^"/', '', $this->apache_compiles['HTTPD_ROOT']));
                if (is_dir($base_path . DIRECTORY_SEPARATOR . 'conf.d')) {
                    $this->apache_config_path = $base_path . DIRECTORY_SEPARATOR . 'conf.d';
                } elseif (is_dir($base_path . DIRECTORY_SEPARATOR . 'other')) {
                    $this->apache_config_path = $base_path . DIRECTORY_SEPARATOR . 'other';
                }
            }
        }

        return $this->apache_config_path;
    }