I have a command in my McCLIM application that allows the user to set pathname defaults: (define-taems-mdp-app-command (com-change-taems-filename-defaults :name t) ((pathname 'directory-pathname :default (make-pathname :directory (pathname-directory (taems-pathname-defaults *application-frame*))) :prompt "New default TAEMS model directory?")) ...) You will see that it takes one argument. I have put it in the file menu of my application, and when I try to invoke it, McCLIM crashes with the following error: Error: KAUAI-GRAPHER::COM-CHANGE-TAEMS-FILENAME-DEFAULTS got 0 args, wanted 1 arg. [condition type: PROGRAM-ERROR] Restart actions (select using :continue): 0: Return to application command loop 1: Abort entirely from this (lisp) process. [Current process: TAEMS CLIM Grapher] [1] CL-USER(1): :bt Evaluation stack: GRAPH-MDP::COM-CHANGE-TAEMS-FILENAME-DEFAULTS <- (METHOD CLIM:EXECUTE-FRAME-COMMAND (CLIM:APPLICATION-FRAME T)) <- (METHOD CLIM:DEFAULT-FRAME-TOP-LEVEL (CLIM:APPLICATION-FRAME)) <- (:INTERNAL (:EFFECTIVE-METHOD 1 T ...) 0) <- (:INTERNAL (MOP:CLASS-DEFAULT-INITARGS GRAPH-MDP::TAEMS-MDP-APP :TOP-LEVEL-LAMBDA) 0) <- (METHOD CLIM:RUN-FRAME-TOP-LEVEL (CLIM:APPLICATION-FRAME)) <- (METHOD CLIM:RUN-FRAME-TOP-LEVEL :AROUND ...) <- (:INTERNAL (:EFFECTIVE-METHOD 1 T ...) 0) <- (:INTERNAL GRAPH-MDP:RUN-GRAPHER 0) My understanding from reading the manual is that when I invoke this command from the menu, it should prompt me to accept the arguments. add-menu-item-to-command-table [Function] Arguments: command-table string type value &key documentation (after :end) keystroke text-style (errorp t) button-type s Adds a command menu item to command-table's menu. The arguments are: command-table Can be either a command table or a symbol that names a command table. string The name of the command menu item. The character case and style of string are ignored. This is how the item will appear in the menu. type This is one of: :command, :menu, or :divider. (:function, called for in the CLIM spec, is not supported in this release.) When type is :command, value should be a command (a cons of a command name followed by a list of the command's arguments), or a command name. (When value is a command name, it behaves as though a command with no arguments was supplied.) In the case where all of the command's required arguments are supplied, clicking a command menu item invokes the command immediately. Otherwise, the user will be prompted for the remaining required arguments. [from the Allegro CLIM manual; the online spec has similar wording.] Can anyone say why McCLIM is crashing here? It seems like the read-frame-command :around method should have invoked command-line-remaining-arguments-for-partial-command. The code is here: (defmethod read-frame-command :around ((frame application-frame) &key (stream *standard-input*)) (with-input-context ('menu-item) (object) (call-next-method) (menu-item (let ((command (command-menu-item-value object))) (unless (listp command) (setq command (list command))) (if (and (typep stream 'interactor-pane) (member *unsupplied-argument-marker* command :test #'eq)) (command-line-read-remaining-arguments-for-partial-command (frame-command-table frame) stream command 0) command))))) Is it possible that the stream is not an interactor-pane when the menu item is selected? For other commands, I have kludged around this problem and made them take no arguments and just accept them "by hand," as it were... Any help would be much appreciated. thanks, R