Subject: Re: CVS commit: src/sys/sys
To: Hubert Feyrer <feyrer@cs.stevens.edu>
From: Jason Thorpe <thorpej@shagadelic.org>
List: source-changes
Date: 12/20/2005 08:09:32
On Dec 19, 2005, at 10:01 PM, Hubert Feyrer wrote:
> On Tue, 20 Dec 2005, YAMAMOTO Takashi wrote:
>>> This is probably a very stupid question, but... what I wonder is
>>> how to
>>> get a "struct device foodev" that way,
>>
>> you can't. you don't need to do so, if you make it really opaque.
>
> What does "opaque" mean? I wonder where all those things come from
> that these pointers point to... X-)
"opaque" means you can't see into it. You don't know, or care, if
it's an int, a pointer, a float, whatever.
> (Yes, I'm aware that this is a very newbie question... I fetched
> myself a bloody nose again trying to dig into our kernel, and still
> have no real idea where to start; I'm aware that this is probably
> not the best point?)
Opaque types are hardly limited to the kernel. pthread_t is an
opaque type, for example.
-- thorpej