>     I'm still thinking we should expose below these fancy procedures the
>     system calls, struct, and flags primitives they use to get and set
>     line disciplines.

The line discipline stuff won't apply to the Windows console. (Well, now
they run a Linux kernel in there, but the classic console still exists.)

For Unix, there's now:

     struct termios orig_mode;
     struct termios raw_mode;

     cfmakeraw(&raw_mode);
     tcgetattr(term_fd, &orig_mode);
     tcsetattr(term_fd, TCSAFLUSH, &raw_mode);
     // ...
     tcsetattr(term_fd, TCSAFLUSH, &orig_mode);

I have some fairly full-featured terminal stuff implementing a line
editor and fullscreen display that doesn't need any other line
discipline or ioctl stuff.

What is the worst that happend from a user's point of view in the
failure mode suggested by Harold (I didn't understand all the details)?
If it's only a couple of lost characters or screen update problem, well,
those happen on a daily basis with all terminal programs :)