# Building on Unix using GNU autotools

This page describes building SWI-Prolog from source for versions prior
to 7.7.20. More recent versions are built using
[cmake](https://cmake.org/). The process is described on [this
page](<unix.html>).

### Preparing the source (when downloading using GIT)

The _tar ball_ is self contained. The GIT repository contains sub
modules and does not contain generated files. The GIT source is
downloaded and prepared for building using the commands below:

```
git clone https://github.com/SWI-Prolog/swipl-devel.git
cd swipl-devel
./prepare
```

Similarly, the sequence to update the source using git and rebuild is

```
make distclean
git pull
./prepare
./build
```

### Getting the prerequisites

Building SWI-Prolog from source requires tools as well as libraries. We
maintain pages that describes the required dependencies by platform. The
last entry of the list below describes the dependencies in platform
independent way.

  - [Debian based linux (Debian, Ubuntu, Mint, Raspberry Pi, ...)](<Debian.html>)
  - [Redhat based linux (Fedora, Redhat, CentOS, ...)](<Redhat.html>)
  - [SuSE](<SuSE.html>)
  - [Mageia](<Mageia.html>)
  - [Other systems (background info)](<prerequisites.html>)

### Using the build.templ script

Both to facilitate frequent installs and to show some common options,
you are invited to use the *|build.templ|* script located in the top
directory. Copy this file to *build* and edit it according to the [EDIT]
instructions in the script. Then simply run the script as below. This
script is fairly independent from versions, so preserve your customised
script for later releases.

==
% tar zxvf swipl-<version>.tar.gz
% cd swipl-<version>
% cp -p build.templ build
% <edit> build
% ./build
==

If the above fails, follow the instructions below.

### Doing it in multiple steps

The configuration on Unix is based on GNU-Autoconf, a set of scripts
that automatically extract system characteristics and creates the
Makefile and C config header config.h. The generated Makefile only works
with GNU-Make. The installation requires an ANSI-C compiler. Configure
prefers the GNU-project C-compiler gcc, but many other compilers work
fine too.  The first step, building SWI-Prolog lite, is outlined below.

==
% gzip -d < swipl-<version>.tar.gz | tar xvfB -
% cd swipl-<version>/src
% ./configure			# see bellow
% make
% [su root]			# for public installation
% make install
==

The second step, building all tools, is only supported for machines on
which building and loading shared libraries is supported, luckily this
is the case on almost all modern operating systems.

The packages are built and installed from the packages directory in the
main distribution directory. The file README there contains additional
information on building the packages. The basic procedure is:

==
% cd swipl-<version>/packages
% ./configure
% make
% [su root]			# for public installation
% make install
==

Finally, packages can be installed one-by-one. With pl installed in a
your $PATH, simply go to the desired package directory and run the
standard GNU/Linux installation procedure. Global configure options such
as installation location are extracted from Prolog. Some package
configure scripts provide additional options that specify the location
of required libraries.

==
% ./configure
% make
% [sudo] make install
==

*configure* is a Bourne Shell script doing the actual configuration for
your computer. The most important options of configure are:

    $ --help :
    Print a list of all available options. See the files INSTALL and
    INSTALL.notes in the distribution for additional information.

    $ --prefix=prefix :
    Set the base directory for the installation. The executables are
    stored in prefix/bin/, the library in prefix/lib/pl-%plversion/ and
    the include files in prefix/include. For public installation (by
    root), /usr/local is the default. For private installation it is
    normal to specify $HOME

    $ --exec_prefix=prefix :
    Overrides the directory for installing the executables to
    exec_prefix/bin/, normally used on heterogeneous networks.

After successful installation, the compilation directory may be removed.

### In case of trouble ...

The file INSTALL in the source directory contains the generic
documentation about installing autoconf-based programs. The file
INSTALL.notes in the same directory contains additional SWI-Prolog
related hints.

If =configure= fails, try using =|bash configure|=. If =make= fails, try
using GNU-make and gcc.

If all fails, have a look at the ../Support.txt page.

## Post installation (JPL)

If you want to call Java from Prolog using JPL, you need to add the directory holding
the JVM shared objects to the dynamic linker search path.  Using default installation on Ubuntu, this is achieved by adding the following to your =|~/.profile|=:

```
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/lib/jvm/java-1.8.0-openjdk-amd64/jre/lib/amd64/server
```