nanogui: Thread: can't open keyboard device

Hi:
When running nano-X, the program is stucked on tcsetattr.  I am running it under Linux framebuffer with KBDSCAN = Y.
If I skip tcsetattr, then the demo.sh will be running OK except that my keyboard is not running properly so that I can't exit from microwindows.

Any idea?
Do I need to set my /dev/tty to any special settings?

Thanks,
Jackie