Unix-like OS's expect to find dynamically linked libraries, like
librosie.so, in a few special places in the filesystem.  In order to
run one of the sample Rosie drivers, you may not want to "install"
librosie by copying it into a system directory.

Two common ways to avoid installing librosie are:

1. Copy it to (or create a link to it in) the directory of the driver
   program you are running.  The setup.sh script should create such a
   link for you.
2. Set the LD_LIBRARY_PATH (Linux) or DYLD_LIBRARY_PATH (OSX) to
   include the directory where librosie lives.  The script C/rtest.sh
   does this, and then runs the rtest binary.