# The SWI-Prolog MacOSX app

SWI-Prolog is an open source implementation of the Prolog programming language. SWI-Prolog targets at developing real-world applications. To achieve this, in concentrates on libraries that facilitate interfacing to other software components, networking and multi-threading. SWI-Prolog can be used from the `Terminal` application, as an standard Mac application started from `Finder`, under GNU-Emacs or under the Eclipse IDE.

## Supported MacOSX versions

MacOS < 10.6 (older than Snow Leopard)
  This binary does not run on MacOS prior to Snow Leopard. You can install SWI-Prolog using MacPorts on most versions.
MacOS 10.6 (Snow Leopard)
  The app does not work on MacOS 10.6. The command line executables (`swipl, swipl-ld`) do work. See below. Note that upgrading Snow Leopard or later to Maverics is free of charge.
MacOS 10.7 and later
  All features work on these versions of MacOS.

### Using the X11 based development tools

The SWI-Prolog development tools, such as the source-level debugger, are based on xpce, SWI-Prolog's native graphics toolkit. This toolkit requires X11, and in particular Xquartz, even on Mac OS X v10.5 to v10.7 where X11 is preinstalled or can be installed as an option. SWI-Prolog's XPCE toolkit is linked against the X11 libraries in `/opt/X11`, Xquartz version 2.7.11.

The SWI-Prolog app can be executed directly from the disk image, can be installed in `/Applications` or in any other location, i.e., it is relocatable. The app advertises itself to the launcher as shell for files with extensions `.pl` and `.prolog`

## Using the commandline tools

The traditional command line tools are included in the app. To access them from the `Terminal` application, add the directory `/Applications/SWI-Prolog.app/Contents/MacOS` to `$PATH` (replace with the actual location if you installed the app in a different location).

The Qt based console for this app is developed by Carlo Capelli.

SWI-Prolog is brought to you by many contributors.