qInstallMessageHandler, Messages only at once when i close EXE? not during runtime

[HappyCoder]

Hello,

up to now i used qDebug() to get messages into the output of QtCreator.
The messages are printed into the output window of QtCreator when they are called.

I created a MessageHandler like it is here: http://doc.qt.io/qt-5/qtglobal.html#...MessageHandler

When i now start my application i don't have ANY messages in my console output
in QtCreator during run time. When i close my EXE all messages are printed out
at once.

What's going wrong here? It seems that all messages are "collected" somewhere
and when the EXE will be closed all printed to the console in QtCreator.
Is it normal when using qInstallMessageHandler?

Windows 7, Qt 5.5.1 and QtCreator 3.5.1

Thx

[anda_skoa]

Looks like you forgot to post the code of your message handler :-)

Cheers,
_

[HappyCoder]

Looks like you forgot to post the code of your message handler :-)
_

It is like in the URL, nothing changed:

void MyMessageOutput(QtMsgType type, const QMessageLogContext &context, const QString &msg)
{
    QByteArray localMsg = msg.toLocal8Bit();
    QString messageType;
    switch (type)
    {
    case QtDebugMsg:
        fprintf(stderr, "DBG: %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
        break;
    case QtInfoMsg:
        fprintf(stderr, "INF: %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
        break;
    case QtWarningMsg:
        fprintf(stderr, "WRN: %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
        break;
    case QtCriticalMsg:
        fprintf(stderr, "CRT: %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
        break;
    case QtFatalMsg:
        fprintf(stderr, "FAT: %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
        abort();
    }
}

void MyMessageOutput(QtMsgType type, const QMessageLogContext &context, const QString &msg)
{
    QByteArray localMsg = msg.toLocal8Bit();
    QString messageType;
    switch (type)
    {
    case QtDebugMsg:
        fprintf(stderr, "DBG: %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
        break;
    case QtInfoMsg:
        fprintf(stderr, "INF: %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
        break;
    case QtWarningMsg:
        fprintf(stderr, "WRN: %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
        break;
    case QtCriticalMsg:
        fprintf(stderr, "CRT: %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
        break;
    case QtFatalMsg:
        fprintf(stderr, "FAT: %s (%s:%u, %s)\n", localMsg.constData(), context.file, context.line, context.function);
        abort();
    }
}

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[anda_skoa]

Usually stderr is not buffered, but since this is Windows, who knows.

Have you tried fflush(stderr) at the end?

Cheers,
_

[HappyCoder]

Have you tried fflush(stderr) at the end?
_

That's it! Now i got the messages at runtime and not all at once when i close the application.

[gurpreettamber]

Yes!! It worked. Logs are now appearing at run-time. Thanks.