On Fri, 30 Aug 2019 17:53:02 +1000, Chris Angelico wrote: > That's because sys.stderr is never changing in your example here. Try > checking whether sys.stdout is a TTY instead. OMG, thanks a lot, this does the trick. > > (Also, why the sleep? Seems unnecessary.) Because without using sleep, the stuff on screen will display very shortly and then disappear. Is this not your testing result?