'Bad file descriptor' error from URL session data task on Apple Watch?

Question

I'm working on an independent watchOS app and I'm testing on the Apple Watch Ultra simulator as well as a couple of real Apple Watch Ultra devices (both have active cellular data service (AT&T), are within 3 feet of their paired iPhones and connected to WiFi, as well).

My app registers with APNs to receive remote notifications. When I receive the token (in didRegisterForRemoteNotifications(withDeviceToken:)), I create a URLSession data task to send it to the server that will generate and send the notifications. This code works 100% of the time on the Apple Watch Ultra simulator but on a real Apple Watch Ultra, about 2/3 of the time, I get the following error message in the Xcode debug console:

2023-05-12 08:32:30.779560-0400 Watch App Prototype[569:586139] PDTask <5110B87C-28D7-48C9-9C68-121C7728FF68>.<2> finished with error [9] Error Domain=NSPOSIXErrorDomain Code=9 "Bad file descriptor" UserInfo={_kCFStreamErrorCodeKey=9, _kCFStreamErrorDomainKey=1, _NSURLErrorRelatedURLSessionTaskErrorKey=(
    "LocalDataPDTask <5110B87C-28D7-48C9-9C68-121C7728FF68>.<2>",
    "LocalDataTask <5110B87C-28D7-48C9-9C68-121C7728FF68>.<2>"
), _NSURLErrorFailingURLSessionTaskErrorKey=LocalDataPDTask <5110B87C-28D7-48C9-9C68-121C7728FF68>.<2>}
2023-05-12 08:32:30.780401-0400 Watch App Prototype[569:586139] Task <5110B87C-28D7-48C9-9C68-121C7728FF68>.<2> finished with error [9] Error Domain=NSPOSIXErrorDomain Code=9 "Bad file descriptor" UserInfo={_kCFStreamErrorCodeKey=9, _kCFStreamErrorDomainKey=1, _NSURLErrorRelatedURLSessionTaskErrorKey=(
    "LocalDataTask <5110B87C-28D7-48C9-9C68-121C7728FF68>.<2>",
    "LocalDataPDTask <5110B87C-28D7-48C9-9C68-121C7728FF68>.<2>",
    "LocalDataTask <5110B87C-28D7-48C9-9C68-121C7728FF68>.<2>"
), _NSURLErrorFailingURLSessionTaskErrorKey=LocalDataTask <5110B87C-28D7-48C9-9C68-121C7728FF68>.<2>}
The operation couldn’t be completed. Bad file descriptor

I ran across this post which describes what appears to be the same/similar problem and that person's code is obviously different than mine so I'm not sure that it's a code issue. When this error occurs, the URL request is definitely not completing.

For what it's worth, here's the code that I'm using to send the URL request:

func perform(_ urlRequest: URLRequest) async throws -> Data {
    let (data, response) = try await urlSession.data(for: urlRequest)
    guard let httpResponse = response as? HTTPURLResponse else {
        throw NetworkError.serverSideError(response: nil)
    }        
    guard (200...299).contains(httpResponse.statusCode) else {
        throw NetworkError.serverSideError(response: httpResponse)
    }
    return data
}

By the way, urlSession in the above code is the URLSession shared singleton. Has anyone else ever run into this error message?

'Bad file descriptor' error from URL session data task on Apple Watch?

0 Answers0