Removed use of dllimport for Windows. Johnson Lin reported that he was getting warnings about it. I think the problem is that I didn't handle the case where you compile the files into your project or statically link. In this case you don't want dllexport or dllimport. From what I read, dllimport is optional (an optimization hint). Since this is becoming a nuisance, I rather just remove it rather than require another build flag.