
			INSTALLING R UNDER UNIX


GENERALITIES

R will configure and build under a number of common Unix platforms
including dec-alpha-osf, freebsd, hpux, linux-elf, sgi-irix, solaris,
and sunos.  In general it is relatively easy to adapt R to new
platforms.  See below for details.


SIMPLE COMPILATION

Choose a place to install the R tree (R is not just a binary, but has
additional data sets, help files, font metrics etc).  Let's call this
place RHOME.  Untar the source code.  This should create directories
src, etc, cmd, help and doc.  Issue the following commands:

	./configure
	make

If these commands execute successfully, the R binary will be copied to
the `$RHOME/bin' directory.  In addition, a shell script font-end
called "R" will be created and copied to the same directory.  You can
copy this script to a place where users can invoke it, for example to
`/usr/local/bin/R'.  You could also copy the man page `R.1' to a place
where your man reader finds it, such as `/usr/local/man/man1'. If you
want to install the complete R tree to, e.g., /usr/local/lib/R, see
section INSTALLATION below.

If you need or want to set certain configure variables to something
other than their default, you can do that by either editing the file
`config.site' or on the command line as

	VAR="..." ./configure              # Bourne shell compatibles
	(setenv VAR "..."; ./configure)    # C shell

One common variable to change is R_PAPERSIZE, which defaults to a4, not
letter.

Make will also build plain text help pages as well as HTML and LaTeX
versions of the documentation (the three kinds can also be generated
separately using make help, make html and make latex).  Note that as
of R version 0.60, you need Perl version 5 to build the documentation.
If this is not available on your system, you can obtain precompiled
documentation files via the `doc/pre-formatted-help' directory of the
Comprehensive R Archive Network (CRAN), see the file `RESOURCES' for
information on CRAN.

Now type R and reach for your S manuals ...


INSTALLATION

After
	./configure
	make
have been completed successfully, you can install the complete R tree
to your system by typing

	make install

This will install to the following directories:

	$prefix/bin		executables
	$prefix/man/man1	man pages
	$prefix/lib/R		all the rest (libraries, online help
				system, ...)

where prefix is determined during configuration (typically /usr/local)
and can be set by running configure with the option

	./configure --prefix=/where/you/want/R/to/go

The prefix of the installation directories can also be seen in the
status message that is displayed at the end of configure.

If you have libraries and header files, e.g. for GNU readline, in
non-system directories, use the variables LIBS (for libraries) and
CPPFLAGS (for header files), respectively, to specify these locations.


USING FORTRAN

To compile R, you need a FORTRAN compiler or f2c, the FORTRAN-to-C
converter.  The default is to search for f77, g77, fort77, f90, xlf,
cf77, and fc (in that order), and then for f2c, and use whichever is
found first; if none is found, R cannot be compiled.  The search
mechanism can be changed using the `--with-g77', `--with-f77', and
`--with-f2c' command line options to configure.  If your FORTRAN
compiler is in a non-standard location, you can specify it via
`--with-f77=path.to.f77'.


TWO-LEVEL MAKE

If you don't need to supply any special arguments to "configure", you
can actually build R simply by typing "make", which will automatically
run "configure" if the configuration files are absent. Since the build
process depends on the results of "configure", the top-level Makefile
does little more than passing control to Makefile.2nd after ensuring
that "configure" has been run.

This has the curious, but harmless, consequence that "make distclean"
and the like may run "configure" and remove the configuration files a
moment later. This looks odd, but is fairly hard to avoid.


NEW PLATFORMS (Standards Hah!)

There are a number of sources of problems when installing R on a new
hardware/os platform.

 1. Floating Point Arithmetic: R supports the POSIX, SVID and IEEE
    models for floating point arithmetic.  The POSIX and SVID models
    provide no problems.  The IEEE model however can be a pain.  The
    problem is that there is no agreement on how to set the signalling
    behavior;  sgi/irix and linux require no special action, freebsd
    requires a call to (the macro) fpsetmask(0) and osf1v3.2 requires
    that computation be done with a -ieee_with_inexact flag etc...
    On a new platform you must find out the magic recipe and add some
    code to make it work.  This can often be done via the file
    config.site which resides in the top level directory.

 2. Shared Libraries: There seems to be very little agreement across
    platforms on what needs to be done to build shared libraries.
    there are many different combinations of flags for the compilers
    and loaders.  The technique we use is to interrogate the X window
    system about what it does (using xmkmf).  This often works, but
    you may have to manually override the results.  Scanning the cc(1)
    and ld(1) manual entries usually reveals the correct incantation.
    Once you know the recipe you can modify the file config.site
    (following the instructions therein) so that the build will use
    these options.

If you do manage to get R running on a new platform please let us know
about it so we can modify the configuration procedures to include that
platform.

If you are having trouble getting R to work on your platform please
feel free to get in touch to ask questions.  We've had a fair amount
of practice at porting R to new platforms...

	R Core Members
