Can I use the ri.h header file to program old-style C programs that make Renderman API calls? I tried to compile this with gcc on Mac OSX but the linker complained about undefined symbols:

#include </Applications/Graphics/3Delight-6.0.4/include/ri.h>

      RtPoint Square[4]= {{.5,.5,.5},{.5,-.5,.5},{-.5,-.5,.5},{-.5,.5,.5}};
      main()
        {
        RiBegin(RI_NULL);
        RiWorldBegin();
        RiSurface("constant",RI_NULL);
        RiPolygon(4, RI_P,(RtPointer)Square,RI_NULL);
        RiWorldEnd();
        RiEnd();
        }