I just realized the following when debugging a CMake (non-qt) project with QtCreator (not using it because of Qt but because it's a nice IDE) and CDB.
The program has a simple cout code line which is properly displayed in the "Application Output" pane when I run the program with Ctrl+R. However, if I debug the same build&run configuration with F5, I cannot see any output.
Where does QtCreator forward stdout to in the second case?
You can see the output printed on the debugging logs, which is a pane under Window->Views->Debugger Log
The right pane shows the expected output. Not a full solution but a very close workaround.
I believe qt creator sees only the output from cdb and it doesn't forward the program's output, but only its own. In fact, the application output pane displays one line of cdb's output related to a system call I make within my program.
This workaround causes a weird side-effect. When cdb hits a breakpoint, the colorscheme of that pane gets reset to default.
On a sidenote, there was a closed bug report stating
There is a difference to the old debugging engine in that the
printf()-output of console-applications is suppressed in
debug/console-builds of Qt Creator builds. In previous versions, the
output used to go to the terminal Qt Creator was started in.
Not true in my case, as launching qtcreator from cmd detaches from cmd.
Try using std::endl or std::flush (if you don't want to change line) at the end of cout, e.g. std::cout << "Hello" << std::endl;
In Windows, OutputDebugString() goes to the "Application Output" window.
You can filter out noise by adding your own Message function:
https://doc.qt.io/qt-6/qtglobal.html#qInstallMessageHandler
Related
Operating Environment: Windows 7, Visual Studio 2010, CLR GUI.
So I've been given the unglorious task of enhancing a GUI application that is started from a command prompt. Because it is. Because poor design decisions by previous implementers. Anyway, it launches one of several GUIs depending upon the input arguments.
I'd like to be able to print back to the same command prompt window if (when) the user types something that the code doesn't understand.
Here's what I've tried (none of which output anything):
int main( array<System::String^>^ args )
{
Application::EnableVisualStyles();
Application::SetCompatibleTextRenderingDefault(false);
OutputDebugString("hello");
Trace::WriteLine("hello");
Debug::Trace::WriteLine("hello");
Console::WriteLine("hello");
std::cout << "hello";
printf("hello");
return 0;
}
Thanks in advance!
Update: I don't want to use AllocConsole(), as that opens a new console that disappears along with all of the data when the application exits. Similarly, a pop-up message box won't work. I'm looking for a way to make the output persistent.
The only way I can get output from the application to date is via a message box (non-persistent) or opening a new console that disappears when the application exits (via AllocConsole() ). And I'm running from a command prompt, not the debugger's "Play" button.
Update
Why the down-vote for not doing research? I spent a day trying to solve this, looking through dozens of posts trying to find a solution, and to date I've found others looking for the same answer, but not finding it. AllocConsole() or changing the project type is always the solution, but neither is a solution for me.
Update
I added the "full code", which is the 2 statements. THAT IS ALL THE CODE. So simple. I'm skipping the start of the GUI because I don't care about that right now, I just want it to print back to the console where the application was started. The most basic HelloWorld. If there are project settings I need to post, I don't know which ones would be relevant. This is where I want to print to the console, before the GUI is ever up. I can't show the GUI if there is an error in the user input.
Right click on the project, select Properties
Under Linker -> System, Change Subsystem from Windows to Console.
A Windows subsystem application cannot write to console, but by changing the subsystem to Console (which can write to the calling console), the Form part of the application can still work (tested in Visual Studio 2010).
I have just started using KDbg and am having a hard time finding the answer to my question. I open a file in KDbg (I opened an executable written in assembly), there is a pop up that says
GDB: Reading symbols from /home/myputer/Desktop/ASMdirectory/chapter5/eatsyscall/eatsyscall...done.
How do I get the option to run the program in the debugger and add breakpoints and etc. It doesn't allow me to click the button to run the program or add any breakpoints, is there an issue here? Am I missing a step? Thanks in advance. BTW I'm using Linux(Ubuntu) and NASM for my assembler.
What are the versions of software you are running?
For example I am running
Ubuntu 12.04,
kdbg 2.5.0 (KDE Development Platform 4.8.5),
gdb 7.4-2012.04,
nasm 2.09.10
You are using Duntemann's book, yes?
I am assuming you changed SECTION .txt to SECTION .text because
when GDB attempts to read symbols it reports "done" instead of "Can't find any code sections in symbol file"
I would recommend using gdb directly instead of kdbg. I do not know of a way to get kdbg to show disassembled code or list (or how to send any gdb commands directly). I think the best that can be done is:
Run kdbg
Open the executable
Switch to the Breakpoints tab
Enter "_start" (which I believe is the only visible symbol you have) in the edit box.
Hit the "Add Breakpoint" button
Hit the "Run" button
Execution should have broken at _start
Switch to the Registers tab
Hit the "Step into by instruction" button to walk through your code
Kdbg does not seem to be able to restart execution. It seems the program must be killed then run again.
So there I am, working on a Silverlight app, and between one build & run and the next, my debug output goes away. Where before I had dozens of lines of Debug.Writeline text, I now have only the module load and thread messages.
Yes, I'm in debug mode (vs. release mode).
Yes, my Output window says "Show output from: Debug".
Yes, when I right-click on the output window, every option is checked.
No, my Tools > options > debugging > general > "Redirect all output text to the immediate window" is not checked.
All I can figure (and it's a wild guess) is that for some reason, the VS debugger isn't attaching to the Silverlight app like it should.
What's weird is this has been happening for the last couple of days, out of the blue. And just as suddenly, all my debug messages start showing up again.
This is VERY frustrating.
EDIT: Of course, after returning to the project after the weekend, all Debug messages are back. No idea what was causing the issue, so I'm sure it will happen again.
Now the question is: should I leave this question open in case the problem arises again in the near future? What happens to an unawarded bounty?
I found the same problem and just by setting options → debugging → output window → Thread Exit Messages to true the output windows was begin to send the right messages !?
I had exactly the same issue. Out of the blue, debug.print stopped working. In my case, it used to go to the Immediate Window. Nothing there. Nothing in the Output window. I followed several suggestions to no avail until I found this one at http://www.experts-exchange.com/questions/26894732/Debug-Print-and-Debug-Write-no-longer-work-in-Visual-Studio-2010.html
There is a context menu in the Output/Debug pane. The "Program Output"
menu item was accidentally cleared.
Checked the item and it started working again (even though my output was the immediate window). What a relief...
Ensure that the DEBUG conditional compilation symbol is defined. The Debug class suggests that you "add the /d:DEBUG option to the compiler command line when you compile your code using a command line, or add #define DEBUG to the top of your file".
Did you create or modify an Application config? If yes: the initial created configuration by VS does contains the necessary wiring configurations to enable the debugging at all. Not sure what and if there are counterparts in Silverlight, but in WPF environments simply replacing the app.config will have the same effect as you expierience.
Check the Immediate Window. Check the options. There is a general setting that says "send Debug output to Immediate Window"
I am testing an F# project using NUnit. On the debug tab of project configuration I have set the debugger to use an external program which is nunit-console here and the working directory to the debug folder of my project. I prefer using nunit-console with the debugger since the GUI version doesn't hit the test file's breakpoints.
When I debug the test the console window appears and disappears and there is no chance to read the output. I have tried Console.Readline(), but it doesn't work because when I directly run the test from a terminal using nunit-console, it fails due to this command.
Is there a way to redirect the nunit-console output to the Visuals Studio's output window?
UPDATE: I could use Thread.Sleep() to delay the nunit-console.exe when I run the test from the console. But from Visual Studio it doesn't happen so I am pretty sure that nunit-console.exe fails to read the test file when the command is issued by Visual Studio. Still, it would be very nice to be able to read the console output, thus the redirection is still desirable.
Either use Tools->Options...->Debugging->General:"Redirect all Output Window text to Immediate Window" and then make sure that the "Immediate Window" is visible with Debug->Windows->Immediate.
Or use NUnit's "/wait" command line option.
Unless I am missing something, you should be able to hit all your breakpoints with the GUI as well, set the startup project to nunit.exe and pass the name of your test DLL as a command line parameter. You will hit the breakpoints in Visual Studio, and your print statments will be in the GUI's output tab.
I'm using Aptana Studio with Pydev 1.5.3 to debug my Django applications. I use PyDev's remote debugger and some code in manage.py and for most of the time this setup is working successfully- I can set breakpoints, inspect variables and step/continue through my code.
However, I'd like to execute arbitrary code at the breakpoint- the thing I really miss after switching from pdb to Eclipse debugging. There is an interactive console available in debug perspective but it is inactive for me.
So my question- is it possible to set up an interactive console in PyDev with remote debugger which could "inject" code at breakpoint?
strange, i am using pydev 1.5.6 for remote debugging and I can use the interactive console - i type the cmmand, hit enter, after a while get results back; check your firewall is not blocking anything (if you are sure, the interactive console works in local mode). there is even settings in pydev source code to set how much of stdout should be returned back to client (in chars), it should work
After some digging I discovered that I can use Expressions view to access variables properties and view results of class methods, but that still isn't a complete console at breakpoint though.
With PyDev 1.5.5 it should be possible:
In "Variables" view, you can right-click on a name, then select "change value".
The console is working as well, albeit a bit tricky.
It is only for inspection and in a very strange way: you have to input the text in the "Debug server" console, and you will get the output in the "filename" console.
Note also that you need to press enter twice, leaving an empty line.
While the "empty line" trick is documented, the issue about two different console for input and output is not, and I think it may be a bug.
On my development stack running Apache + mod_wsgi entering commands into the console had their output routed to the site's error logs. To resolve this you have set the stdoutToServer=True and sterrToServer=True to route capture all output to the PyDev remote debugger:
from pydevsrc import pydevd;pydevd.settrace('192.168.2.8', stdoutToServer=True, stderrToServer=True) #clone and put on python path: https://github.com/tenXer/PyDevSrc