MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    QProcess p;
    p.setProgram("aplay");
    //p.setProgram("cp");
    QStringList l;
    //l << "/dev/stdin" << "myfile.txt";
    l << "-D" << "hw:0" << "-c" << "2"  << "-f"  << "S16_LE" << "-r" << "44100";
    p.setArguments(l);
    QDataStream d(&p);
    p.start(QIODevice::WriteOnly|QIODevice::Unbuffered);
    p.waitForStarted();
    d << "\n";
    QThread::msleep(20);
    d << "\n";
    qDebug() << p.state();
    if(p.state()!=2) {
        qDebug() << "Error:" << p.error();
    }
    char samples[11]="sdfgjhtr\r\n";
    for(quint16 n=1;n<300;n++) {
        for(quint16 m=0;m<441;m++)
            d.writeBytes(samples,11);
        QThread::msleep(20);
        p.waitForBytesWritten(-1);
    }
    qDebug()<<p.bytesToWrite();
    //p.readAllStandardOutput();
    qDebug()<<p.bytesToWrite();
    qDebug()<<p.isWritable();
    p.waitForBytesWritten(30000);
    p.closeWriteChannel();
    //p.readAllStandardOutput();
    QThread::msleep(200);
    qDebug()<<p.bytesToWrite();
    p.waitForBytesWritten(-1);
    QThread::msleep(200);
    qDebug()<<p.bytesToWrite();
    //qDebug()<<p.readAllStandardError();
    p.kill();
    p.waitForFinished();
}

MainWindow::~MainWindow()
{
    delete ui;
}