As described below, the previous code specific to APPLE was
improperly specifying the path:

/Users/pieper/Downloads/Slicer-4.0.beta-r15645-Darwin
common:Slicer-4.0.beta-r15645-Darwin pieper$ find . -iname libarc\*
./lib/Slicer3/Users/partyd/Kitware/Slicer/build/libarchive-install
./lib/Slicer3/Users/partyd/Kitware/Slicer/build/libarchive-install/lib/libarchive.8.dylib
./lib/Slicer3/Users/partyd/Kitware/Slicer/build/libarchive-install/lib/libarchive.a
./lib/Slicer3/Users/partyd/Kitware/Slicer/build/libarchive-install/lib/libarchive.dylib

git-svn-id: http://svn.slicer.org/Slicer4/trunk@15648 3bd1e089-480b-0410-8dfb-8563597acbee