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From: guerby@gnat.com (Laurent Guerby)
Subject: Re: access aliased obstacle
Date: 1996/07/06
Message-ID: <ws9d928rekk.fsf@schonberg.cs.nyu.edu>#1/1
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sender: guerby@schonberg.cs.nyu.edu
references: <4rfig3$l5d@news1.delphi.com>
organization: New York University
reply-to: guerby@gnat.com
newsgroups: comp.lang.ada
Date: 1996-07-06T00:00:00+00:00
List-Id: <comp.lang.ada>


> To pass a data structure to an OS routine I tried
> 
>   type elements(discriminant: enumeration_type:=normal_value) is record
>     case discriminant is
>     ...
>   end record;
>   for elements'size use 64;  -- size does not vary
> 
>   type list_of_elements is array(1 .. 17) of aliased elements;
[...]

   Are you trying to interface a C union (array of)? If it's the case,
I think the use of Unchecked_Union may be of interest (and I believe
it will be portable between Ada 95 implementation).

   An array of general access may also be closer to C here.

-- 
Laurent Guerby <guerby@gnat.com>, Team Ada.
   "Use the Source, Luke. The Source will be with you, always (GPL)."