When certain SDL-based programs (e.g. prboom, dosbox) are run from the console (not X) and terminate abruptly for some reason (e.g. killed or segfaults), the screen locks up; It just goes black, and remains black until you reboot.
This is in contrast with the hello_video and hello_triangle demos which return the console to its original state even if they are terminated abruptly.
What exactly is going wrong here, and is there a way to recover it without rebooting?
I have observed this in Debian Squeeze. I do not know if other OSes are affected.
Edit: I should clarify only the console (HDMI/RCA output, USB keyboard) is affected, not ssh connections (which continue to work fine.)