Don't log messages go in the stderr by default?

[ratijas]

Don't they go in the stderr by default?

I mean, they follow the default Qt handler which is also quite configurable with env variable: https://doc.qt.io/qt-5/debug.html#warning-and-debugging-messages / https://doc.qt.io/qt-5/qloggingcategory.html#configuring-categories

Originally posted by @ogoffart in #86 (comment)

After years of looking for a cause or at least a working solution, I have finally been pointed in the right direction. This whole time Qt apps were trying to log into system journal, and not to stdout/stderr. It can be reverted by simply setting QT_LOGGING_TO_CONSOLE environment variable, as suggested in QTCREATORBUG-24756 (check out linked issues and mail thread as well). Note that QT_LOGGING_TO_CONSOLE does NOT appear in the documentation pages linked above.

I filled as issue QTCREATORBUG-25935 for Qt Creator to set it on by default when running apps from IDE.

If I knew it at the time of #86, I'd rather pass logs from Rust to Qt side. But oh well… Now we have a reason to implement it too.