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    SubjectRe: [linux-fbdev] fbdev 2.4.0 cleanups
    Date
    James A Simmons writes:
    > Okay lets consider this. Now some video cards use different apertures for
    > their video memory. What I mean the framebuffer location is different for
    > 8 bit (it's little endian) and 16 bit (big endian). Consider this.
    > You start your X server in 8 bit mode. Now it will have write access to
    > /dev/fb. Now you start some app which opens /dev/fb in read only mode and
    > gets the current fix info. fix->smem_start will point to the little endian
    > aperture right. Now your X server has properly ALT whatever function keys
    > that do change the video mode. Since the X server has write access it can
    > change the modes. So now you switch to 16 bit color mode which means
    > fix->smem_start has changed to the big aperture. Your other app is still
    > writing to where the little endian aperture was which is the wrong place.

    Unless there has been a major change in X11, I don't think that's possible.
    I believe that the only thing that Alt +/- can do is change resolution, not
    colour depth.

    IIRC, colour depth requires a restart of the server and all applications.

    Please correct me if I'm wrong.
    _____
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    | | Russell King rmk@arm.linux.org.uk --- ---
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    / | THE developer of ARM Linux |+| /|\
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