[Linux-fbdev-devel] Re: fbdev, console, (video) overlay/underlay& fbtv

[Geert U. <ge...@li...>]

On Thu, 12 Jul 2001, Romain Dolbeau wrote:
> Geert Uytterhoeven wrote:
> > In 2.5.x, we will change behavior: only one app can open /dev/fb* at the same
> > time, and VC switching is adisabled as long as /dev/fb* is open.
> 
> So, XFree86-4 open /dev/fb to use the framebuffer, you
> can't go back to a VC until you have exited X ?
> Looks like a big backward step to me. But of course
> it solves a _lot_ of problems :-)

No. You can still receive a signal when the user wants to switch VC.

In fact this is what X already does, but explicitly: it requests a new VC,
switches to it, disables VC switching, and installs a VC switching signal
handler. When the user wants to switch VCs, X gets the signal, unmaps graphics,
restores to text mode, and switches to the new VC.

So the only thing that changes is that VC switching is implicitly disabled when
/dev/fb* is opened.

> Also, if all VC are on FB0, what happen if you mmap() FB1 ?
> Does it blocks VC switching or not ?

Of course opening /dev/fbX affects VCs tied to fbX only.

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@li...

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds