isTrustedPHPDir example

$_filepath = $_script_dir .  $_file;
                        break;
                    }
                }
            }
        }
        if ($_filepath == false) {
            $compiler->trigger_template_error("{include_php} file '{$_file}' is not readable", $compiler->lex->taglineno);
        }

        if (isset($compiler->smarty->security_policy)) {
            $compiler->smarty->security_policy->isTrustedPHPDir($_filepath);
        }

        if (isset($_attr['assign'])) {
            // output will be stored in a smarty variable instead of being displayed             $_assign = $_attr['assign'];
        }
        $_once = '_once';
        if (isset($_attr['once'])) {
            if ($_attr['once'] == 'false') {
                $_once = '';
            }
        }