QextSerialPort - detect disconnection

Question

I have a device connected to the computer as "COM8". I'd like to know when it is unplugged from the computer, so I used the following code to detect:

m_receiverCom->isWritable();
m_receiverCom->isOpen();  

However, they still returned true after I unplugged the device. How can I detect whether the device is plugged or not ?

Answer 1

You queried the port, not the device. Send some kind of query message to the device that will produce a response message.

Answer 2

Although an old thread, prevent people from getting stuck. I just ran into this problem, and I successfully used qextserialport to detect serial port disconnect/connect using:

QextSerialPort *serial_monitor;
serial_monitor = new QextSerialEnumerator();
serial_monitor->setUpNotifications();

connect(serial_monitor, SIGNAL(deviceRemoved(QextPortInfo)), this, SLOT(_handleUSBError(QextPortInfo)));