Titan : using native hadoop libraries on MacOSX

Once you have built the native hadoop libraries on your MacOSX, you need to add this bit of code to bin/gremlin.sh so that it can find them:

if [ -e "${HADOOP_PREFIX}/lib/native/libhadoop.dylib" ]; then
   LIB_PATH="${HADOOP_PREFIX}/lib/native"
   if [ -n "${LD_LIBRARY_PATH:-}" ]; then
       LD_LIBRARY_PATH="${LIB_PATH}:${LD_LIBRARY_PATH}"     # For Linux
   else
       LD_LIBRARY_PATH="${LIB_PATH}"
   fi

   if [ -n "${DYLD_LIBRARY_PATH:-}" ]; then
       DYLD_LIBRARY_PATH="${LIB_PATH}:${DYLD_LIBRARY_PATH}" # For Mac
   else
       DYLD_LIBRARY_PATH="${LIB_PATH}"
   fi
fi

The only oddity here is that the script uses "set -u" at the top, which makes bash complain if you use uninitialized variables. So you have to append ":-" to the variables that you are testing. You can see that in the lines that test LD_LIBRARY_PATH etc.