void class_printIvars(Class cl) {
    unsigned int ivarCount;
    Ivar *ivars = class_copyIvarList(cl, &ivarCount);
    printf("Ivars for %s: \n", class_getName(cl));
    for (int i = 0; i < ivarCount; i++) {
        Ivar ivar = ivars[i];
        printf("%s : %s \n",
               ivar_getName(ivar),
               ivar_getTypeEncoding(ivar));
    }
    free(ivars);
}

int main(int argc, const char * argv[]) {
    @autoreleasepool {
      Class bundle = objc_getClass("NSBundle");
      class_printIvars(bundle);
    }
}