Im coding mp3 encode / ripping tool and because i have licence to realbasic im gonna make user interface with it Technical part im gonna make with akrip.dll and i have develope it more by my own way now. The meaning is use threads for ripping and encode in the same time and i have thinking to use _beginthread function. In the future im gonna develope that tool to use multicore processors. But now the problem is how to design threading because now all functions in the dll are called by their own way from a realbasic so there is no mainthread at all. How it is possible to plan threads to these functions? Or is it necessary make threading in realbasic?