Macintosh Changes and System 7 Support

Several options can now be set in a preferences file. This file is a text file, is must be called XLS Preferences, and it must be located in the same folder as the application. Each line in the file represents an option specification. The first word identifies the option, the remaining words make up the option data. The option names currently supported are

the Workspace entry specifies a default workspace to use. Unless specified separately, listener font properties are identical to editor font ones. As an example, a preferences file containing the entries

EditFontName Courier
EditFontSize 12
Workspace Alliance Drive:MPW:Programs:New XLS:xlisp.wks
Color off

The dashed line separating system apple menu items from application items is now supplied internally -- a dash item is now no longer necessary. This should result in a single dash under both System 6 and System 7.

Under Macintosh System 7 XLISP-STAT now continues to operate while in background. If the variable *use-notifier*  is not nil , then notification occurs when a modal dialog is to be opened or when the system tries to read from the listener. The notification consists of a beep, a flashing icon on the system menu, and a diamond marking the application name in the system menu.

Minimal support for examining processes on the current computer and for sending local or remote apple events is now available. The function launch-application  takes either a file name string argument or an application signature argument and launches the corresponding application. By default the application is launched in foreground; specifying an optional argument as non- nil causes the application to be launched in background. The value returned is a process information record if the launch succeeds, or nil if the launch fails. Process information is currently encoded as a list of the process name, process signature, process serial number, time of process start and run time of the process. This representation may change.

Currently applications can only be found by signature if they are located on the boot volume.

> (encode-signature "X1St")
1479627636

A list of process information records for all running processes is returned by get-process-list , and get-front-process  returns the process information for the current front process. The set-front-process  function takes a process name string, signature code, or process information record and makes the corresponding process the front process. If the argument is a string or integer, then the first process, if any, with the corresponding name or signature is used.

XLISP-STAT now responds to the four required Apple events (Open Application, Open Documents, Print Documents, and Quit Application). The Print event is ignored. Currently new workspaces can only be opened at startup (i. e. as part of the initial high level event), but text files can be opened by double clicking them or dragging them onto the XLISP-STAT icon at any time. In addition, the Do Script event is supported (class 'misc', event 'dosc'). This event takes a direct parameter that is a string and interprets it as a lisp expression. The expression is evaluated, the result is printed to a string, and the string is returned as the direct parameter of the result. For example, if you have the Alpha shareware editor, then from a Tcl shell window you can send an apple event to a running XLISP-STAT process asking XLISP-STAT to make a system beep sound:

Alpha.5.55> dosc -c 'X1St' -s "(sysbeep)"
NIL

You can also send Apple events to processes on the same or on remote computers using the function send-apple-event . At the moment this function allows you to send events that contain parameters that are strings, integers, or floating point numbers. If a result is expected it should contain no required parameters or a required direct parameter that can be coerced to a string. In particular, this allows Do Script events to be sent to other XLISP-STAT processes. The send-apple-event  function has three required parameters, two four-character strings specifying the event class and type, and an address specifier for the event's receiver. The address can be

• The symbol t , which means the current application is the target, a self send.
• A string representing a process name on the local computer.
• An integer representing the signature code of a process on the current computer.
• A process information record as returned by launch-application  or by get-process-list .
• A target specifier as returned by browse-apple-event-targets  or by get-apple-event-target .

:data : Either nil , the default, or a string to be used as the direct parameter of the event, or a list of lists. If a list of lists is used, then the sublists must contain two items, a key string identifying the parameter (such as "----" for a direct parameter) and the data item. Data items can be integers, floating point numbers or strings.

:wait-reply : Wait for a reply if non- nil , the default.

:timeout : The symbol t for the default timeout (about a minute), an integer for a specific value, or nil for no timeout. If not supplied, the default timeout is used.

:can-switch-layer : Whether or not the receiver should be allowed to come to the front if it requires interaction.

(send-apple-event "aevt" "abou" "Finder")

To locate a target on the local machine or a machine on the network you can use the interactive browse-apple-event-targets  function. This function presents a dialog box that lists available processes for all Macintoshes on a local network; if the local network is connected to an internet the dialog also presents a list of AppleTalk zones to choose from. Several keyword arguments are available for controlling the appearance of the dialog:

:prompt : A prompt string to show at the top of the dialog.

:application-list-label : A string to show over the program list item.

:type : The connection type, which defaults to "PPCToolBox".

:name : A string specifying the name of the application to link to. Only applications with this name are shown.

:signature : An integer signature code. Only applications with this signature are shown.

:object : The name of a macintosh.

:type : The connection type, which defaults to "PPCToolBox".

:zone : An AppleTalk zone name.

As an example, suppose an XLISP-STAT process is running on another Macintosh named "Fred's Macintosh" and that all permissions are suitably set. We can send a sysbeep command to this Macintosh using the expression

(let* ((sig (encode-signature "X1St"))
       (target (get-apple-event-target :object "Fred's Macintosh")))
  (when target
        (send-apple-event "misc" "dosc" target :data "(sysbeep)")))

The support included for Apple events is rather minimal. The main reason I have not yet made it more extensive is that I don't know what kinds of events will be most useful for communicating with other applications. If anyone has any ideas or would like to help extending this, please let me know.

One problem that comes up on the Macintosh is the need to account for the screen size. Currently a background bitmap the size and depth of the primary screen is allocated within the partition. The size of this bitmap is

For a monochrome display this is fairly trivial, and a 3M partition should be adequate for most purposes (though this of course depends on what is loaded). But for a display using 32-bit color, this is 4M. At the moment, this calculation needs to be done manually and you need to make adjustments to your partition accordingly. I will try to come up with a better solution in the future.

The open-file-dialog  function now accepts a third optional parameter for specifying the file types to show. If this parameter is nil , all files are shown. If it is a string or a list of strings, only files of the corresponding types are shown.The sefault is "TEXT". At present,at most four types can be given; this limitation will be removed in the future.