void cvCircle(CvArr* img, CvPoint center, int radius, CvScalar color, int thickness, int line_type, int shift) {
    void *fptr;

    fptr = dlsym(_Chcv_handle, "cvCircle_chdl");
    if(fptr == NULL) {
        fprintf(_stderr, "Error: %s(): dlsym(): %s\n", __func__,  dlerror());
        return;
    }
    dlrunfun(fptr, NULL, cvCircle, img, center, radius, color, thickness, line_type, shift);
}
