Argh, sorry for the previous posts. I had some sort of Ctrl-lock, that is, the keyboard acted as if Ctrl was pressed all the time. Now I know that Ctrl+Enter is a shortcut to send an email. I accidentally closed some shells by pressing the D key.
I was able to get rid off it by switching to a text console with Alt-F1 (the additional Ctrl key was also not needed) and back. Alex Schuster writes: > The next test gives 93 seconds, that's nice. What is not so nice is that emerge -a --depclean took over half an hour of CPU time, needing half a gigabyte of memory. WOW. Wonko