Unable to retrieve version information with command line options on Windows

[jfbourdon]

What is the bug or the crash?

I'm unable to retrieve version information with command line option --version even though the option exists. Nothing is printed. Other commands like --help (image below that display what --version should do), --profile or --profiles-path work as intended.

Steps to reproduce the issue

Call qgis-ltr-bin --version or qgis-bin --version and see that nothing is printed.

Versions

QGIS 3.20.0 and QGIS 3.16.9, both via OSGeo4W install
Windows 10 Version 1809

[gioman]

Also it should print that infos in the terminal/console, and not open that dialog, I think.

[agiudiceandrea]

I'm unable to retrieve version information with command line option --version

It's an issue that occurs on Windows platforms. Also reported in #37465 (comment).

Also it should print that infos in the terminal/console, and not open that dialog, I think.

It seems this is by design, introduced with bd23bf1 and f61c993 probably just to workaround the same issue that occurs with "--version".

QGIS/src/app/main.cpp

Lines 180 to 187 in 3e28304

	#ifdef Q_OS_WIN
	MessageBox( nullptr,
	msg.join( QString() ).toLocal8Bit().constData(),
	"QGIS command line options",
	MB_OK );
	#else
	std::cout << msg.join( QString() ).toLocal8Bit().constData();
	#endif

[jfbourdon]

Also it should print that infos in the terminal/console, and not open that dialog, I think.

Sorry for the confusion, I now edited my description to make it clear that --help works but not --version.

The argument --version or -v should be read...

QGIS/src/app/main.cpp

Lines 641 to 645 in f14ddac

	else if ( arg == QLatin1String( "--version" ) || arg == QLatin1String( "-v" ) )
	{
	version();
	return EXIT_SUCCESS;
	}

Is it that version() function doesn't produce a valid string on Windows?

QGIS/src/app/main.cpp

Lines 121 to 125 in f14ddac

	void version( )
	{
	const QString msg = QStringLiteral( "QGIS %1 '%2' (%3)\n" ).arg( VERSION ).arg( RELEASE_NAME ).arg( QGSVERSION );
	std::cout << msg.toStdString();
	}

Elsewhere strings seem to be printed with msg.toLocal8Bit().constData(); instead of msg.toStdString(); . I must say that I don't know much about C++.

[agiudiceandrea]

Is it that version() function doesn't produce a valid string on Windows?

AFAIK the issue is due to the fact that, normally, std::cout cannot display the text string in the console when a WIN32 GUI application is executed in the CLI.
In fact, you can redirect the output of qgis-bin --version to a file using qgis-bin --version > version.txt and see a valid version text string successfully written in the file.

I now edited my description to make it clear that --help works

Do you mean it's OK for you that the --version output would be displayed in a MessageBox window like for the --help output?
In this case it should be simple to fix the issue.

EDIT: it seems it is also by design that a MessageBox window is not used for the --version output. See #30198 and in particular #30198 (review)

[jfbourdon]

Do you mean it's OK for you that the --version output would be displayed in a MessageBox window like for the --help output?

No, I was just trying to say that all arguments were doing what we are expecting them to do. Maybe I should have remove my last sentence altogether.

Thanks for the trick qgis-bin --version > version.txt, I didn't thought about trying that. For my intended usage, it will do the job just fine.