$security
      
       $security true/false, default is false. Security is good for
       situations when you have untrusted parties editing the templates
       (via ftp for example) and you want to reduce the risk of system
       security compromises through the template language. Turning on
       security enforces the following rules to the template language,
       unless specifially overridden with $security_settings:
      
      
       If $php_handling is set to SMARTY_PHP_ALLOW, this is
         implicitly changed to SMARTY_PHP_PASSTHRU
       PHP functions are not allowed in IF statements,
         except those specified in the $security_settings
       templates can only be included from directories
         listed in the $secure_dir array
       local files can only be fetched from directories
         listed in the $secure_dir array using {fetch}
       {php}{/php} tags are not allowed
       PHP functions are not allowed as modifiers, except
         those specified in the $security_settings