Re: [Qemu-devel] [PATCH] display: stop using DT_NOGRAPHIC, use DT_NONE

[Peter Maydell]

On 28 June 2013 12:50, Michael Tokarev <address@hidden> wrote:
> Um. With either -nographic or -display none, there's no "display"
> per se, and it is the "display" who relays keypresses and such into
> guest.  Without display, the guest becomes headless completely, not
> only it does not have a monitor of a video card, but also does not
> have keyboard or mouse or other similar stuff.  Or it may have these,
> but you can't "touch" neither keyboard nor mouse because you don't
> "see" them without a display.  Fun thing but here we go.
>
> This ctrl+c handling is only about when you explicitly redirected
> some other char device to guest, such as serial port.  Which don't
> have much to do with display I think, hence I don't understand the
> logic here.

The point is that one of the things -nographic does, as well
as disabling the graphics display, is to redirect the serial
port (among other things) to stdio. That's why there's code
in the char backend that cares about "did you say -nographic":
because -nographic means "no graphic display, serial port on
terminal, send ctrl-c in terminal to guest rather than killing
qemu, [some other stuff]".

It would be nice to be able to say "-nographic is equivalent to
'-display none -serial stdio -disable-ctrl-c -other-things'"
but I'm not sure exactly what the -other-things are or even
if we can set them all on the command line specifically.

-- PMM