title: QNetworkAccessManager multiple uploads fail
body: <p>In my App, I have a method to upload files to the server, this works fine. </p>
  
  <p>But when I call this method multiple times at once (like iterating over the result of a chooseFilesDialog) the first 7 (more or less) files are uploaded correctly, the others never get uploaded.</p>
  
  <p>I think this has to be linked with the fact the server doesn't allow more than X connections from the same source maybe?</p>
  
  <p>How can I make sure the upload waits for a free, established connection?</p>
  
  <p>this is my method:</p>
  
  <pre><code>QString Api::FTPUpload(QString origin, QString destination)
  {
      qint64 timestamp = QDateTime::currentMSecsSinceEpoch();
      QUrl url("ftp://ftp."+getLSPro("domain")+destination);
      url.setUserName(getLSPro("user"));
      url.setPassword(getLSPro("pwd"));
  
      QFile *data = new QFile(origin, this);
      if (data-&gt;open(QIODevice::ReadOnly))
      {
          QNetworkAccessManager *nam = new QNetworkAccessManager();
          QNetworkReply *reply = nam-&gt;put(QNetworkRequest(url), data);
          reply-&gt;setObjectName(QString::number(timestamp));
          connect(reply, SIGNAL(uploadProgress(qint64, qint64)), SLOT(uploadProgress(qint64, qint64)));
  
          return QString::number(timestamp);
      }
      else
      {
          qDebug() &lt;&lt; "Could not open file to FTP";
          return 0;
      }
  }
  
  void Api::uploadProgress(qint64 done, qint64 total) {
      QNetworkReply *reply = (QNetworkReply*)sender();
      emit broadCast("uploadProgress","{\"ref\":\""+reply-&gt;objectName()+"\" , \"done\":\""+QString::number(done)+"\", \"total\":\""+QString::number(total)+"\"}");
  }
  </code></pre>