The vc_... version is native Windows version. Run it in a Windows command prompt. The "bad address" with the cygwin version is a known problem and has been solved by another user: PriiDash(TM): Enhanced Instrument Panel / Data Logger - Now Open Sourced! | Page 3 | PriusChat To compile the program for Cygwin I have been using NetBeans IDE. I have yet to learn how to do it from the command line. But the IDE is so easy to use that I may put it off forever.