Function rs2_set_options_changed_callback_cpp 

pub unsafe extern "C" fn rs2_set_options_changed_callback_cpp(
    options: *mut rs2_options,
    callback: *mut rs2_options_changed_callback,
    error: *mut *mut rs2_error,
)

Sets a callback in case an option in this options container value is updated \param[in] options the options container \param[in] callback callback object created from c++ application. ownership over the callback object is moved to librealsense \param[out] error if non-null, receives any error that occurs during this call, otherwise, errors are ignored