Command and Description Command Handler Arguments DISCOVER This command performs three functions: ¶   Creates an attribute list ¶   Filters users ¶   Locates records used to populate the user profile The  DISCOVER  command, as part of the protocol, describes a list of attributes that must be filled in for each user found during a populate. The user-defined  DISCOVER  handler is responsible for locating user records to be populated and for checking those user records against a filter list, if one was specified. If a  FILTER  command was sent, then an internal attribute list of the items to be filtered is created. The DISCOVER  handler is responsible for enforcing the filter. Once a record is found, the handler checks it using the CheckFilterList( )  method to determine if it should be populated. When all information for that user record has been found, it is sent to the Application Management Toolkit using the  SendRecord( )  method. After all records have been located, checked, and sent to the toolkit, the  SendTermination(2)  method is called, indicating an end of discovery. Internal handler:  disc_handler When a command handler is registered with the  DISCOVER command, it is redirected to another command called  REAL_DISC. You cannot directly register a command with  REAL_DISK. This preserves the internal handler for DISCOVER, called  disc_handler, from being overridden and provides a mechanism to delay invocation of the user-defined command handler until the actual discovery process has begun. The delay occurs because both the  FILTER  and DISCOVER  commands must be completed before the real discovery can occur. (Continued) Attribute list Developing Your Application in Perl 58 User Administration Version 3.8