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From: Martin Krischik <martin@krischik.com>
Newsgroups: comp.lang.ada
Subject: Re: Ada to C Interface: Passing Pointers Via System.Address
Date: Thu, 13 Jan 2005 18:14:40 +0100
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Date: 2005-01-13T18:14:40+01:00
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tmoran@acm.org wrote:

>> My C functions return pointers to data structures (very large
>> structures). I need to then pass the pointer to the data struct to the
>> Ada code and
>> back into other C functions.  There is no interaction with the data
>> structure in the Ada code except to pass the pointer from one C function
>> to another.
>   If the data being passed through Ada is a black box to Ada, why not
> just declare a type of the appropriate size, eg
>   type C_Thing is range 0 .. 2**32-1;
>   for C_Thing'size use 32;

The World is on the dawn of 64bit CPUs. Better be prepared:

type C_Thing is mod System.Memory_Size;
for C_Thing'Size use System.Word_Size;

Martin

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