access & dump framebuffer

access & dump framebuffer

[J.]

Sunday, October 16 12:57:35

Hi .. 

Question - I was thinking about writing a program that creates a
screendump [image] only from the cli. [not X]. Where should I access
the data that is displayed on the screen? Directly from the hardware, or
from the kernel somewhere or .. ?

Any comments, thoughts or hints are appreciated.

Thankx.

J.


-- 
Don't worry Ma'am. We're university students, - we know what we're doing.

Re: access & dump framebuffer

[Eric Bambach]

J.

I haven't done this before but perhaps I can get you started.

I wouldnt try to do it from the kernel becuase drivers have already been 
written to do that. In order to display an image the kernel will have to be 
compiled with FrameBuffer support for whichever videocard the machine has. 

Next, I would look into the bootsplash packages and how that uses the 
framebuffer device for displaying images. There are also vaious libraries 
that you can link traditional X programs against so they can be used in an 
environment without X. They use the framebuffer device instead. I seem to 
recall that people have even gotten the mozilla browser to open up in a cli 
environment. Search for those libraries and see how they do it.

My main point is that you want to do is find out how to use the video 
framebuffer device once you know the machine's kernel supports it. 

 Hope that gets you started!

On Sunday 16 October 2005 06:01 am, J. wrote:
> Sunday, October 16 12:57:35
>
> Hi ..
>
> Question - I was thinking about writing a program that creates a
> screendump [image] only from the cli. [not X]. Where should I access
> the data that is displayed on the screen? Directly from the hardware, or
> from the kernel somewhere or .. ?
>
> Any comments, thoughts or hints are appreciated.
>
> Thankx.
>
> J.

-- 
----------------------------------------
--EB

> All is fine except that I can reliably "oops" it simply by trying to read
> from /proc/apm (e.g. cat /proc/apm).
> oops output and ksymoops-2.3.4 output is attached.
> Is there anything else I can contribute?

The latitude and longtitude of the bios writers current position, and
a ballistic missile.

                --Alan Cox LKML-December 08,2000 

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