Re: Gives Bus error in memcpy() in coping /dev/fb0 to a file.

["Antonino A. Daplas" <adaplas@gmail.com>]

On Fri, 2007-03-09 at 10:21 +0530, Vishal Soni wrote:
> On Thursday 08 March 2007 18:35, Antonino A. Daplas wrote:
> > On Wed, 2007-03-07 at 17:20 +0530, Vishal Soni wrote:
> > > [root@tw pcapp]# ./pcapp
> > > 1024x768, 16bpp
> > > framebuffer device mapped to memory @ 0xb7db3000.
> > > FB_FRAME mapped to memory @ 0xb7c33000.
> > > Bus error
> >
> > I don't think vfb's framebuffer can be mmapped.  It's fixable, but
> > nobody seems to have a need for it,  yet.
> >
> > Tony
> fb is getting successfully mapped.. its just that memcpy gives bus error when 
> i try to copy the mapped memory of framebuffer device to a "mapped file,"
> 
> Well, I am able to get the ball rolling by writing the mapped framebuffer onto 
> the file by using write system call

Unless you modified vfb yourself, it's not possible because
fix->smem_start is not set all (it's pointing to NULL). What's actually
being mmapped is physical addres 0UL.

Tony



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