iphone 5s和iphone 6（tcp）的区别

Question

Is there any difference between iPhone 5s and iPhone 6 in TCP connection ? I've run the same tcp code in 5s and 6, and in 6 is working fine, but 5s suddenly stop while getting data. When code running stop, event handler not working neither. iOS version in two devices are same to 12.1.4.

init code

CFStreamCreatePairWithSocketToHost(kCFAllocatorDefault,
                                   (__bridge CFStringRef) serverip,
                                    serverport,
                                    & _readStream,
                                    & _writeStream);

 self.inputStream = (__bridge NSInputStream *)self.readStream;
 [self.inputStream setDelegate:self];
 [self.inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];

 self.outputStream = (__bridge NSOutputStream *)self.writeStream;
 [self.outputStream setDelegate:self];
 [self.outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];

 [self.inputStream open];
 [self.outputStream open];

event handler code

else if(eventCode == NSStreamEventHasBytesAvailable)
{
    if([aStream isEqual: self.inputStream])
    {
        NSInteger len = 0;
        uint8_t buf[4096];
        len = [self.inputStream read:buf maxLength:4096];

        if(len > 0)
        {
            NSMutableData* data = [[NSMutableData alloc] initWithLength:0];
            [data appendBytes: (const void *)buf length:len];
            [file_handler writeData:data];

            len_read = len_read + (int)len;

            if(len_read >= file_length) // download complete
            {
                @synchronized (self)
                {
                    [self.inputStream close];
                    [self.inputStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];
                    [self.inputStream setDelegate:nil];
                    self.inputStream = nil;

                    [self.outputStream close];
                    [self.outputStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];
                    [self.outputStream setDelegate:nil];
                    self.outputStream = nil;

Answer 1

I don't know why it have difference between 5s and 6 yet.

But I solve this problem by setting socket receive buffer size.