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The libsunperf library is the Sun Performance Library, which
is a set of highly optimized functions for computationally
intensive operations, such as those used be 3dDeconvolve for
solving systems of equations.

If you have that on your system, you might have to add the
directory it resides in to your LD_LIBRARY_PATH environment
variable. If you do not, then you will probably have to
compile the AFNI package yourself. In doing that, you will
want to choose the proper Makefile, Makefile.solaris28_gcc,
maybe.

The Makefile.solaris28_gcc does not use the Performance
Library. So it might be appropriate for you.

If you do want to compile, HowTo #0 can be of help (see
[afni.nimh.nih.gov]) In text:
[afni.nimh.nih.gov] .

But the basic steps are simple:

wget [afni.nimh.nih.gov]
gzip -d afni_src.tgz
tar xf afni_src.tar
cd afni_src
make -f Makefile.solaris28_gcc totality

Then put the results into your afni binary directory.
Assuming you have a ~/abin directory, then:

mv solaris28_gcc/* ~/abin

If you have further questions, please let me know.

- rick