From: Nathan K. <nat...@gm...> - 2006-10-09 00:04:13
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Hey folks, I'm messing with some virtual framebuffering, and had a question. When in userspace, if I want to read the contents of the framebuffer I just do a open("/dev/fb0",O_RDONLY) and I've got a nice clean capture of the screen. Where, however, does this data live in kernelspace? My vfb driver declares a pointer and then allocates whatever memory the display needs, basically width*height*bytes_per_pixel bytes. A lot like the variable "videomemory" in drivers/video/vfb.c. If I try to copy this data, however, it comes out garbled. Some parts look a little like the original, but most of it is pretty random. Is there another home for this pixel data somewhere? I tried reading from info->screen_base, but got exactly the same results. Much thanks, Nathan |