1. Added #ifdef extern "C" to public header files.
2. Changed variables that are key words in c++, to different names (like ns instead of namespace).
3. Add a test_c++.sh for c++ compiling.
1. Added #ifdef extern "C" to public header files.
2. Changed variables that are key words in c++, to different names (like ns instead of namespace).
3. Changed char* to const char* for constant strings.