Use a subclass of Perm to provide parameters for your permission class and to implement your own perm_invalid function.

         class My_Perm extends Perm {
           var $classname = "My_Perm";

           var $permissions = array (
             "user"          => 1,
             "author"        => 2,
             "editor"        => 4,
             "moderator"     => 8,
             "admin"         => 16
           );

           function perm_invalid($does_have, $must_have) {
             global $perm, $auth, $sess;

             include("perminvalid.ihtml");
           }
         }
   

Use the page management functions (see above) to use your permission subclass. The feature name for permission management is perm; provide the name of your Perm subclass as a parameter to the perm feature. The perm feature requires the sess feature and the auth feature:

         page_open(array("sess" => "My_Session", "auth" => "My_Auth", "perm" => "My_Perm"));
   

Use the check() instance method to protect your page:

         $perm->check("admin");  ## This page is for users with admin rights only.
   

Use have_perm() to create protected functionality on a page:

         <?php
           if ($perm->have_perm("admin")):
          ?>
           <h1>Admin only functionality</h1>
         <?php
           endif;
          ?>