I installed dosbox on Ubuntu linux, and when I run it, I get this message: Exit to error: Can't init SDL No available video device. Could somebody tell me what I did wrong?

Thank you so much.

I have a little problem. I've put dosbox onto my usb flash drive, and I couldn't figure out how to have it mount a directory on it automatically (using a frontend, or whatnot) whenever I run it, no matter what computer I have the drive connected to. When you connect the drive to a computer, the …