Error C2664

[dodoxor]

I've ref class. I 've to use a function "ccap_start_capturing" that take a ptr,and a ptr to a callback function(on_jpeg_received) and another ptr to a function on_exit_capturing defined in this class. Both "ccap_start_capturing" and "on_jpeg_received" functions are defined in a file c that i can't modify. //#include ... ref class CamPanObj{ public: CamPanObj(){ camaddr=new camaddr_t(); } protected: ~CamPanObj() {//... } public: static void on_exit_capturing(int code) {/.. } CAPID rec_start(void) { ... capid=ccap_start_capturing(camaddr,on_jpeg_received,on_exit_capturing); return (capid); } }; It returns a compile error error C2664: 'ccap_start_capturing' : cannot convert parameter 3 from 'void (__clrcall *)(int)' to 'void (__cdecl *)(int)' None of the functions with this name in scope match the target type How can i resolve it? Thanks, regards.