Unable to see the QDebug Messages on console.

Rohith

Hi,
Recently i have started to program and compile with Qt-5.7.1. I have successfully compiled for desktop and compiling and execution everything is fine. But the problem is i am unable to see the debug messages on the linux console, i am not getting where i did mistake or is anything more need to be added while compiling qtsource specially in order to see the qdebug messages on console.

Help me to resolve my problem.

Thanks in advance,
Rohith.G

yuvaram

can you share your .pro file .

Rohith

@yuvaram

Hi Yuvaram thanks for replying, here is my .pro file please check it out.

TEMPLATE = app
TARGET = CndM
INCLUDEPATH += .
QT+=  core widgets gui sql
OUTPUT += Console
# Input
HEADERS += database.h widget.h
FORMS += widget.ui
SOURCES += database.cpp main.cpp widget.cpp

Vinod Kuntoji

@Rohith ,

Add,
CONFIG += console

yuvaram

@Rohith
You need to add CONFIG type in profile, as shown
TEMPLATE = app
TARGET = CndM
INCLUDEPATH += .
QT+= core widgets gui sql
CONFIG += console

Input

HEADERS += database.h widget.h
FORMS += widget.ui
SOURCES += database.cpp main.cpp widget.cpp

Rohith

@yuvaram

Hi yuvaram and vijay thanks for replying, i have tried as per your suggestion but no use i am unable to see the qdebug messages.

my new .pro file

TEMPLATE = app
TARGET = CndM
INCLUDEPATH += .

QT+= core widgets gui sql
CONFIG += console

# Input
HEADERS += database.h widget.h
FORMS += widget.ui
SOURCES += database.cpp main.cpp widget.cpp

J.Hilk

@Rohith
you'll have to rerun qmake after changes in your *.pro file

Rohith

@J.Hilk

Hi Hilk thanks for replying, i have recompiled the project from start i.e
i have done
makedistclean
qmake -project
added all the inputs
qmake
make

yuvaram

@Rohith
Try to delete build folder , then try clean, qmake, build, run

Rohith

@yuvaram

Hi Yuvaram,

There is no separate build folder for my project, i am compiling through command line.
What is your intention i am following the same thing i am doing i.e fresh compilation, but still unable to see the messages.

Vinod Kuntoji

@Rohith ,

Try compiling your code through Qt Creator, and check the qDebugs in application output?

hskoglund

Hi, also, as a workaround, you can capture all qDebug messages and print them out yourself, just call qInstallMessageHandler, say like this:

#include "stdio.h"
void messageHandler(QtMsgType type, const QMessageLogContext &context, const QString &msg)
{
    printf(qUtf8Printable(msg));
    printf("\n");
}

int main(int argc, char *argv[])
{
    qInstallMessageHandler(messageHandler);

    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    return a.exec();
}

TM9412

Hi @Rohith and others

Are you able to print the q debug message on console ??

I am also trying to print the QDebug Messages on console but it is not printing

Paul Colby

Hi @Rohith,

i am unable to see the debug messages on the linux console

Try running your application after:

export QT_LOGGING_RULES="*.debug=true"

The default message handler decides whether or not to filter debug messages (indeed, all log categories and/or levels) based on rules loaded in five different places (see "Order of evaluation" under QLoggingCategory - Logging Rules). And recent versions of Linux (Ubuntu at least, and Fedora I've read) ship with debug output disabled by default. You can enable debug output a number of ways (see the previous link), and can even decide which components to log at which levels (eg enable debug logging of Qt's network components if you wish). It's pretty powerful, but a little bit complex IMO.

Another way is:

QLoggingCategory::defaultCategory()->setEnabled(QtDebugMsg, true);

I sometimes like to do that in response to a -d or --debug command line option.

Cheers.

TM9412

correct @Paul-Colby
thanks