Command and Description Command Handler Arguments EXISTS This command is a request from the application connection manager to determine if a specific record exists. If the record was not found, the handler should call the  DataError( )  method. The protocol sends a record type with this command. No default handler. See also:  DataError( ),  GetAttributeVersion( ), GetAttributeChange( ) String FILTER By default, this command creates an internal list of the items to be filtered. The list is an inclusive filter. Items in the list should be included by populate. The items are available to the  DISCOVER handler, but are not filtered automatically. The default handler can be overridden by registering your own command handler using the  RegisterCmdHandler( )  method. Note that if you do this, the internal list is unavailable and the methods CheckFilterList( )  and  GetFilterList( )  will return nothing. The protocol does not send a record type with this command. Default handler:  filter_handler  Can override. See also:  DISCOVER,  START_DISCOVER,  CheckFilterList( ), GetFilterList( ) Item list MODIFY The handler for this command is responsible for updating the records for the application. The protocol sends a record type with this command. No default handler. See also:  DISTRIBUTE,  GetAttributeVersion( ), GetAttributeChange( ) Record Developing Your Application in Perl 60 User Administration Version 3.8