Yes, lvmkmf is a command in gcc. I think the problem might be larger though. CINs are LabVIEW version and OS dependent. You cannot compile a cin on UNIX for use on a Windows computer. This is because the c code is compiled for that computer (making it OS dependent) then it is linked making it LabVIEW version dependent. When the lsb is loaded into LabVIEW and run, LabVIEW just runs the machine code the original compiler created.