Qt 5.9 | Qt Serial Port | Command Line Writer Sync Example | main.cpp Example File

Qt 5.9.4 Reference Documentation

# main.cpp Example File

cwritersync/main.cpp

      /****************************************************************************
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      ** Copyright (C) 2013 Laszlo Papp <lpapp@kde.org>
      ** Contact: https://www.qt.io/licensing/
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      #include <QtSerialPort/QSerialPort>

      #include <QTextStream>
      #include <QCoreApplication>
      #include <QFile>
      #include <QStringList>

      QT_USE_NAMESPACE

      int main(int argc, char *argv[])
      {
          QCoreApplication coreApplication(argc, argv);
          int argumentCount = QCoreApplication::arguments().size();
          QStringList argumentList = QCoreApplication::arguments();

          QTextStream standardOutput(stdout);

          if (argumentCount == 1) {
              standardOutput << QObject::tr("Usage: %1 <serialportname> [baudrate]").arg(argumentList.first()) << endl;
              return 1;
          }

          QSerialPort serialPort;
          QString serialPortName = argumentList.at(1);
          serialPort.setPortName(serialPortName);

          int serialPortBaudRate = (argumentCount > 2) ? argumentList.at(2).toInt() : QSerialPort::Baud9600;
          serialPort.setBaudRate(serialPortBaudRate);

          if (!serialPort.open(QIODevice::WriteOnly)) {
              standardOutput << QObject::tr("Failed to open port %1, error: %2").arg(serialPortName).arg(serialPort.errorString()) << endl;
              return 1;
          }

          QFile dataFile;
          if (!dataFile.open(stdin, QIODevice::ReadOnly)) {
              standardOutput << QObject::tr("Failed to open stdin for reading") << endl;
              return 1;
          }

          QByteArray writeData(dataFile.readAll());
          dataFile.close();

          if (writeData.isEmpty()) {
              standardOutput << QObject::tr("Either no data was currently available on the standard input for reading, or an error occurred for port %1, error: %2").arg(serialPortName).arg(serialPort.errorString()) << endl;
              return 1;
          }

          qint64 bytesWritten = serialPort.write(writeData);

          if (bytesWritten == -1) {
              standardOutput << QObject::tr("Failed to write the data to port %1, error: %2").arg(serialPortName).arg(serialPort.errorString()) << endl;
              return 1;
          } else if (bytesWritten != writeData.size()) {
              standardOutput << QObject::tr("Failed to write all the data to port %1, error: %2").arg(serialPortName).arg(serialPort.errorString()) << endl;
              return 1;
          } else if (!serialPort.waitForBytesWritten(5000)) {
              standardOutput << QObject::tr("Operation timed out or an error occurred for port %1, error: %2").arg(serialPortName).arg(serialPort.errorString()) << endl;
              return 1;
          }

          standardOutput << QObject::tr("Data successfully sent to port %1").arg(serialPortName) << endl;

          return 0;
      }