Hi!
On Wed, 26 Sep 2001, Tom Goetze wrote:
> Looking through the initialization info, I find:
> [...]
> Can I use any of this information to correctly set
> my struct video_buffer before I call:
> ioctl(fd, VIDIOCSFBUF, &vid_buf);
No.
> It sure looks like it gets set during initialization, so why is it
> suddenly unset when I get around to changing the window size?
It was never set up to that time. It must be set from the outside world of
the driver. The frame buffer (*this* frame buffer) is located in your
graphics card.
You can use a DGA inquiry like v4l-conf (from xawtv package) does. Or,
if you prefer a command line option for your program, you can visually
look for the frame buffer address among the start messages of X.
It's a good behaviour of the driver if it rejects every non-root user who
tries to call VIDIOCSFBUF.
Bye,
Rolf
