Oops... there isn't a mcCntlGetResetCodes() API function.
It is actually a compilation of a few constants and some profile settings in the order presented below. I'll add a "Get" function at some point.
The constants:
G40 // Always add G40 before G20 or G21!
G80 // Always add G80!
These next ones are in section/key, default format:
DefaultMode/UnitsMode, G20
DefaultMode/TraverseMode, G00
DefaultMode/MotionMode, G64
DefaultMode/DistanceMode, G90
DefaultMode/CenterMode, G91.1
DefaultMode/FeedMode, G95
DefaultMode/Plane, G17
DefaultMode/CanedCycleRetract, G98
DefaultMode/SpindleMode, G97S0
DefaultMode/UserDefaults1, ""
DefaultMode/UserDefaults2, ""
So construct a string by adding the constants and reading all of that from the profile, append your desired work coordinate system, and then set the new reset codes with mcCntlSetResetCodes().
Steve