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Date: Thu, 22 Sep 2005 08:51:58 +0200
From: Helge Hafting <helge.hafting@aitel.hist.no>
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To: Valdis.Kletnieks@vt.edu
CC: rep stsb <repstsb@yahoo.ca>, linux-kernel@vger.kernel.org,
       06020051@lums.edu.pk
Subject: Re: In-kernel graphics subsystem
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Valdis.Kletnieks@vt.edu wrote:

>On Thu, 22 Sep 2005 01:51:20 EDT, rep stsb said:
>
>  
>
>>1. Convert svgalib drivers into kernel modules to get
>>v-sync interrupts. 
>>
>>2. Write a windowing program on svgalib. 
>>    
>>
>
>Wouldn't it make more sense to extend the current framebuffer driver
>support to support v-sync? (framebuffers are already in the kernel, and
>there were so many security holes with svgalib-based programs that it left
>a bad taste in a lot of people's mouths)
>
>And having gotten a v-sync interrupt, what would you *do* with it?
>You'll need an API here....
>  
>
Simple.  What we want from such interrupts, is to wait for them, no?
So lets use one of the existing structures made for waiting.  One example
is a file descriptor.  Do a blocking read, which the kernel unblocks when
the interrupt comes in. A file descriptor also supports things like
select() if need be.

Helge Hafting