IOBluetooth: deviceInquiryStarted and deviceInquiryComplete never called

Question

I'm scanning for Bluetooth devices on macOS 13.1 using IOBluetoothDeviceInquiry. The scanning itself works, but only the deviceInquiryDeviceFound delegate method gets called. For the remaining methods:

deviceInquiryStarted never fires, even though the inquiry obviously starts;
deviceInquiryComplete never fires, and indeed the inquiry never seems to end (the program keeps outputting Found peer... console logs);
When updateNewDeviceNames is set to true, the delegate methods related to updating device names are nonetheless never called.

Setting inquiryLength has no effect. The documentation states:

if you have the inquiry object updating device names for you, the whole inquiry process could be much longer than the specified length... If you -must- have a strict inquiry length, disable name updates.

But scanning continues indefinitely even when I set updateNewDeviceNames to false.

Here's my code:

import IOBluetooth

class Inquiry: NSObject {
    private lazy var inquiry: IOBluetoothDeviceInquiry = {
        let inquiry: IOBluetoothDeviceInquiry = IOBluetoothDeviceInquiry()
        inquiry.delegate = self
        inquiry.updateNewDeviceNames = false
        return inquiry
    }()
    lazy var foundDevices: [Any]! = self.inquiry.foundDevices()

    private var continuation: CheckedContinuation<Void, Never>?
    func start() async -> () {
        await withCheckedContinuation { continuation in
            self.continuation = continuation
            self.inquiry.start()
        }
    }
}

extension Inquiry: IOBluetoothDeviceInquiryDelegate {
    func deviceInquiryStarted(_ sender: IOBluetoothDeviceInquiry!) {
        print("inquiry started")
    }
    func deviceInquiryComplete(_ sender: IOBluetoothDeviceInquiry!, error: IOReturn, aborted: Bool) {
        print("inquiry complete")
        continuation?.resume()
    }
    func deviceInquiryDeviceFound(_ sender: IOBluetoothDeviceInquiry!, device: IOBluetoothDevice!) {
        print("device found: \(device.addressString!)")
    }
}

let inquiry: Inquiry = Inquiry()
await inquiry.start()
print(inquiry.foundDevices!)

As I'm writing a command line tool, I wrap the start method in a continuation. Other than that it's pretty much identical to other examples of IOBluetoothDeviceInquiry usage I've found (e.g. this one, which has the same problems when I try running it).

I'm really at a loss as to why this isn't working, any help would be greatly appreciated!

IOBluetooth: deviceInquiryStarted and deviceInquiryComplete never called

0 Answers0