Message-Id:	<m0wg9Vn-000S2ZC@ciati.edu.ar>
Comments:	Authenticated sender is <salvador AT natacha DOT inti DOT edu DOT ar>
From:	"Salvador Eduardo Tropea (SET)" <salvador AT inti DOT edu DOT ar>
Organization:	INTI
To:	wilsonl AT sfu DOT ca (Wilson Wang Shun Leung)
Date:	Mon, 23 Jun 1997 17:09:57 +0000
MIME-Version:	1.0
Subject:	Re: "far" pointer question
CC:	djgpp AT delorie DOT com

wilsonl AT sfu DOT ca (Wilson Wang Shun Leung) wrote:

> But now my question is how I can convert the information
> I have to a pointer which I can actually use for
> read/write data.  What I now have is a selector (the
> content that goes to segment register) and a offset of
> zero.  
Look in the sys/farptr.h file, you'll find the macros to use these values.

> Can I just use the real mode calculation like
> this one:
>    int *port;
>    port = ((DWORD)selector) * 16  + offset
No way!.
 
> where DWORD is 32 bit wide and selector is 16 bit.
> 
> My specific questions are
>   Is the pointer I defined (port) 32 bit wide?
>   What if my offset is 32 bit wide? Then the above
>   calculation should be all wrong. 
All wrong, the value is a SELECTOR not a SEGMENT, you must put the selector in 
one of the segment (read selector ;-) registers and use the 32 pointer.

> Am I missing something? 
Yes, look the macros.

SET 
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