pub unsafe extern "C" fn MQTTAsync_setDeliveryCompleteCallback(
handle: MQTTAsync,
context: *mut c_void,
dc: MQTTAsync_deliveryComplete
) -> c_int
pub unsafe extern "C" fn MQTTAsync_setDeliveryCompleteCallback(
handle: MQTTAsync,
context: *mut c_void,
dc: MQTTAsync_deliveryComplete
) -> c_int