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To: Terry Lambert <terry@lambert.org>
cc: hackers@freebsd.org, multimedia@freebsd.org
Subject: Re: mmap problems? 
In-reply-to: Your message of "Wed, 18 Dec 1996 14:01:51 MST."
             <199612182101.OAA10384@phaeton.artisoft.com> 
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Date: Wed, 18 Dec 1996 13:06:11 -0800
From: Amancio Hasty <hasty@rah.star-gate.com>
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>From The Desk Of Terry Lambert :
> > I have an old program "tv" which used to work okay. 
> > 
> >   frame_size = 38896;
> >         if ((video = open("/dev/meteor0", O_RDONLY)) < 0) {
> >                 fprintf(stderr, "open failed: %s\n", strerror(errno));
> >                 exit(1);
> >         }
> > 
> > After running the program several times, tv exits with a a memory access
> > violation. It  looks like the system is not
> > giving me access to the last page of the frame buffer. Any hints?
> 
> Look at the meteor driver; the page range limitation is imposed at
> that level.
> 
> 
> 					Terry Lambert
> 					terry@lambert.org
> ---

Hi,

I am a little confuse . Why would "tv" work 3 or 5 times then fail to run
because the driver did not mmap properly the pages?