When i writing large data,for example 18MB data over QTcpSocket,the QTcpSocket terminated in Writing process...
first i used this code for writing:
Qt Code: 
  1. client_socket->write(packet,packet.size());
  2.        client_socket->waitForBytesWritten();
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above code is not work correctly,and then i use this code for sending:
Qt Code: 
  1. if (packet.size()>25344)
  2.     {
  3.         QDataStream data_stream(packet);
  4.         data_stream.setVersion(QDataStream::Qt_5_3);
  5.         while (!data_stream.atEnd())
  6.         {
  7.             int len=1024;
  8.             char buffer[len];
  9.             int size_read=data_stream.readRawData(buffer,len);
  10.             if (size_read==-1)
  11.                 cout<<"ERROR!";
  12.             client_socket->write(buffer,size_read);
  13.             client_socket->waitForBytesWritten();
  14.         }
  15.     }
  16.     else
  17.     {
  18.         client_socket->write(packet,packet.size());
  19.         client_socket->waitForBytesWritten();
  20.     }
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and in another hand i using this code for reading data :
Qt Code: 
  1. void server::readyRead()
  2. {
  3.  
  4.     QTcpSocket *i_client=(QTcpSocket*) sender();
  5.     quint16 packet_size=i_client->bytesAvailable();//Read Count Bytes waiting on line
  6.     qDebug()<<"Packet Recived,Packet len: "<<QString::number(packet_size)<<"\n";
  7.  
  8.     if (packet_size>0)
  9.     {
  10.  
  11.         QByteArray recive_bytes=i_client->read(packet_size);//Read Packet
  12.         //...
  13.      }
  14. }
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second way is better,but in both of tow methods ,QTcpSocket terminated after sending some bytes!
what's the problem!?