iOS - GCDAsyncUdpSocket 抛出错误域=NSPOSIXErrorDomain 代码=65 "No route to host"

Question

有时我会收到这个错误

Error Domain=NSPOSIXErrorDomain Code=65 "No route to host" UserInfo={NSLocalizedDescription=No route to host, NSLocalizedFailureReason=Error in send() function.}

在某些路由器中打开 udp 套接字时。我不知道是什么原因造成的。

这是我打开 udp 套接字的代码:

- (void)openSocket
{
    if(_asyncUdpSocket == nil)
    {
        _asyncUdpSocket = [[GCDAsyncUdpSocket alloc] initWithDelegate:self delegateQueue:dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)];
    }

    if(![_asyncUdpSocket isClosed])
    {
        return;
    }

    NSError *error;

    if (![_asyncUdpSocket enableBroadcast:YES error:&error])
    {
        NSLog(@"AsyncUdp: enable broadcast failed error: %@", error);
    }

    if (![_asyncUdpSocket bindToPort:_port error:&error])
    {
        NSLog(@"AsyncUdp: bind to port %li failed error: %@", (unsigned long)_port, error);
    }

    if (![_asyncUdpSocket joinMulticastGroup:_address error:&error])
    {
        NSLog(@"AsyncUdp: join multicast group %@ failed error: %@", _address, error);
    }

    if(![_asyncUdpSocket beginReceiving:&error])
    {
        NSLog(@"AsynUdp: begin receiving error: %@", error);
    }

    if(error != nil)
    {
        NSLog(@"Udp failed to open!");

        [_delegate onUdpSocketDidOpenfailed];
    }

    else
    {
        NSLog(@"UdpSocket - opend udp socket successful!");

        [_delegate onUdpSocketDidOpen];
    }
}

请注意，这种情况在 iPhone 7 中经常发生

Answer 1

将 Xcode 更新到版本 12.5 后，我在运行 DLNA App 项目时遇到了同样的问题。我通过将 Xcode 降级到版本 12.4 来修复它。