Accessing SWI-Prolog source via GIT

GIT is a fast version control system developed by Linus Torvalds and currently maintained by Junio C Hamano. Here is our motivation for choosing GIT for managing the SWI-Prolog sources. You should use the GIT version if you want to stay up-to-date and/or you want to contribute to the project. Many professional users opt for this route.

First install GIT for your platform. You need at least version 1.6.0 because the SWI-Prolog repository uses the GIT submodule features. Many modern Unix versions come with GIT installed. If your version is too old, installing a new version from source is simple. On MS-Windows we use msysGit, which is easily installed and except for being much slower than its Unix counterpart appears to do the job flawlessly. If you want graphical tools on Windows, please check out TortoiseGit.

With GIT installed, you can clone the repository from one of the addresses below. Please use the git:// access if you can as it is much faster. The HTTP gateway provides you with access if a proxy or firewall denies direct internet access to the git port (9418).

The development branch is kept in its own repository at

Initial checkout is achieved using the command below, which creates a directory pl below the current directory. The download does not contain generated documention and configuration files, neither the required stand-alone submodules. Use the ./prepare script to fetch these. This script also runs on Windows using the bash-shell that comes with msysGit. In msysGit it cannot create the configure scripts, but this warning is harmless because configure is not used on Windows. 

% git clone git://www.swi-prolog.org/home/pl/git/pl.git
% cd pl
% ./prepare

Next, consult the file INSTALL for further instructions for installing SWI-Prolog from source. You can update to the latest version using the following commands from the toplevel directory: 

% make distclean 	(typically you can ignore errors)
% git pull
% ./prepare
% ./build
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