Error: __tcp_connection_write_eof_block_invoke Write close callback received error - iOS 10

While sending XML base API Request to ONVIF Camera. It worked fine on ios 9 device, but giving '500 Internal Error' on iOS 10.

XCode 8 Console prints below error messages:

2016-09-30 12:39:51.295419 VCPlugin[278:10183] [] nw_socket_get_input_frames recvmsg(fd 12, 1024 bytes): [54] Connection reset by peer
2016-09-30 12:39:51.301221 VCPlugin[278:10228] [] nw_socket_write_close shutdown(12, SHUT_WR): [57] Socket is not connected
2016-09-30 12:39:51.301307 VCPlugin[278:10228] [] nw_endpoint_flow_service_writes [3 10.107.2.153:80 ready socket-flow (satisfied)] Write request has 0 frame count, 0 byte count
2016-09-30 12:39:51.301903 VCPlugin[278:10185] [] __tcp_connection_write_eof_block_invoke Write close callback received error: [89] Operation canceled
2016-09-30 12:41:13.492053 VCPlugin[278:10287] [] __tcp_connection_write_eof_block_invoke Write close callback received error: [57] Socket is not connected
2016-09-30 12:42:51.278617 VCPlugin[278:10228] [] __tcp_connection_write_eof_block_invoke Write close callback received error: [22] Invalid argument

If user retry and retry three-to-four times, then after get valid xml response from server.

I don't know this iOS 10 behaviour.

this is code i have written for call XML API post request:

NSMutableURLRequest * urlRequest = [NSMutableURLRequest requestWithURL:url];
[urlRequest setHTTPMethod:@"POST"];
[urlRequest setHTTPBody:body];
[urlRequest setValue: @"application/soap+xml" forHTTPHeaderField:@"Content-Type"];
[urlRequest setValue: @"application/soap+xml" forHTTPHeaderField:@"Accept"];

NSURLSessionDataTask * dataTask = [defaultSession dataTaskWithRequest:urlRequest completionHandler:^(NSData *data1, NSURLResponse *response, NSError *error) {
        NSLog(@"Response:%@ %@\n", response, error);
        if(error == nil)
        {
             NSString * text = [[NSString alloc] initWithData: data1 encoding: NSUTF8StringEncoding];
              NSLog(@"Data = %@",text);
        }
}];

[dataTask resume];

Also read Apple Form, but not get solution.

try this code:

I have the same issue, but there is something you can do to,

1) Go in Product -> Scheme -> Edit Scheme
2) Run Section on the left, select Argument Tab and in Environment Variable put this.