Allegro CL version 8.2
Significant update since 8.2 release.

Mac OS X: IDE installation for Express Users

This document contains the following sections:

1.0 Installing X11 and GTK - Required for the IDE
2.0 Installing Allegro CL
3.0 Testing that the installation of Allegro CL on Mac OS X was successful
4.0 Tutorials and additional useful information

This rewrite of the instructions was done in April, 2011. Installation for both the 32-bit and 64-bit Lisp with the IDE is greatly simplified. If you have any difficulty, please contact for assistance.

Allegro CL requires Mac OS X 10.5 or later.

The installation of Allegro CL is described in complete detail in installation.htm. Allegro CL Express users who intend to use the IDE may prefer to use this abbreviated guide for the IDE on Mac OS X only.

Installation involves installing Allegro CL and installing certain other software (such as X11 and GTK) needed to use the IDE.

1.0 Installing X11 and GTK - Required for the IDE

Installing X11

Install This is often already installed (check /Applications/Utilities/ If it is not installed, it can be found on your Mac OS X installation medium.

Installing GTK

You need GTK to run the IDE. GTK may already be installed but may not be installed correctly for Allegro CL purposes, and the following will ensure that GTK will work for Allegro CL and related products.

The GTK .dmg file was listed as a download along with the Allegro CL Express Download and should have been downloaded with the Allegro CL Express download. You can also obtain a copy from

  1. Download the GTK+-Framework-2.22.dmg file to the local hard disk and open it.
  2. In the Finder window that pops up, drag the Gtk.framework file onto Frameworks (an alias for /Library/Frameworks) on the right. This will install the Gtk framework in the right place on your system.

    If you should get an error message about insufficient permissions, it's likely you have an older version of the framework installed. To get rid of the old version, type this into a terminal window:

     sudo rm -rf /Library/Frameworks/{Gtk,Cairo,GLib}.framework

    and retry this step.

After the Gtk.framework file is installed in this directory, the IDE and Common Graphics will be ready to use. See cgide.htm for more information on Common Graphics and the IDE.

2.0 Installing Allegro CL

Here are the steps to install Allegro CL Express (we assume the acl82express-macosx-x86.dmg file has been downloaded):

  1. Double-click on the image. It will open the .dmg file and mount the disk image. Inside there is a single directory, called AllegroCL.
  2. Copy the directory to the desired location. The AllegroCL directory can be copied (by clicking and dragging) anywhere.

That's all there is to the installation of Allegro CL (you may need to install additional tools as described in the next section). Just click and drag it your preferred location. Of course, /Applications is a good location to use, if you don't know where to put it.

3.0 Testing that the installation of Allegro CL on Mac OS X was successful

We will now test the installation. Open the directory where Allegro CL Express is installed (typically /Applications). Open Allegro CL and click on the allegro-express executable:


Allegro CL and the IDE should start up. In the Debug windows, you should see the banner and perhaps additional messages, and the first prompt, like (but probably not identical to) this:

Allegro CL Express Edition 8.2 [Mac OS X]
Copyright (C) 1985-2010, Franz Inc., Oakland, CA, USA.  All Rights Reserved.
;; Optimization settings: safety 1, space 1, speed 1, debug 2.
;; For a complete description of all compiler switches given the
;; current optimization settings evaluate (EXPLAIN-COMPILER-SETTINGS).
;; Current reader case mode: :case-insensitive-upper

You can type forms to the prompt, like (* 20 30) and the result (600) will be displayed.

We recommend that you immediately get updates. You should see the Install menu to the right of the main window's menu bar. Choose New Patches and the Download Patches will appear. Click on the List New Patches button at the bottom to see what is available and then click Download Patches. It will download any new patches (since you just installed, that is all patches). You may have to update and restart Allegro CL after the patches and updates have been downloaded (in order for the updates and patches to take effect). You do this by running by typing the following to a prompt in a Terminal Window (Applications > Utilities > Terminal):


4.0 Tutorials and additional useful information

introduction.htm is a general introduction to the documentation. cgide.htm links to all IDE/Common Graphics documentation. Look at the section Platform-specific information in that document, which has some Mac-specific information.

There are recorded Lisp classes available at and there is additional information elsewhere on the Franz Inc. website at

Copyright (c) 1998-2016, Franz Inc. Oakland, CA., USA. All rights reserved.
This page is new in the 8.2 release.
Created 2016.6.21.

Allegro CL version 8.2
Significant update since 8.2 release.