ROOT on MacOS X requires X11 to run interactively. If you have not yet installed X11, install it following the instruction given here.

As of ROOT v.3.01.05, MacOS X is officially supported. We had, however, some problems with compiling ROOT on MacOS X10.2. These problems have been solved and necessary patches have been applied to the CVS tree. Consequently, ROOT v.3.03.09b and later should compile and run out of the box.
So now building "ROOT" is fairly straightforward.
Moreover some official binary distributions for MacOS 10.3 are availabe. If you just want to use ROOT, there is no need for you to compile it. The instruction given below is for those who might want to build it yourself.

[1] Compilation Conditions

MacOS X Release 10.3.2
standard Mach Kernel (Darwin 6.3)
Apple's X11 for MacOS X
[2] Compilation Procedure

If you want to try the current CVS tree, do

$ export
$ cvs login
(Logging in to
CVS password: cvs
$ cvs -z3 checkout root

or if you just want to use the production version, do

$ tar -zxvf ../orig/root_v3.10.02.source.tar.gz

then follow the steps below:

$ su
# pushd /cern/pro/lib
# ln -s libpythia6134.a libPythia6.a
# ln -s libjetset74.a libPythia.a

# exit
$ cd root
$ export ROOTSYS=`pwd`
$ export PATH=$ROOTSYS/bin:$PATH
$ ./configure macosx
$ make

[3] Installation of a Precompiled Binary Package

Thanks to Remi Mommsen and the ROOT team, ROOT for MacOS X is now available as a Fink package from the official ROOT site. For non-Fink users, however, I prepared a binary tarball below. All you need is to expand the tarball in wherever directory you want to install it.
For instance, if you want to install it as /opt/root/pro, do the following:

$ su
# tar -zxvf <somewhere>/root_v3.10.02-macosx10.3.tar.gz   -C /opt/root
# ln -s root_v3.10.02-macosx10.3 /opt/root/pro
# exit
$ export ROOTSYS=/opt/root/pro
$ export PATH=$PATH:$ROOTSYS/bin

Back to Keisuke Fujii's HEP on X Page January 13, 2004