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From: "Beard, Frank" <beardf@spawar.navy.mil>
Newsgroups: comp.lang.ada
Subject: RE: Variable length raw-byte data
Date: Tue, 12 Dec 2000 16:11:13 -0500
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Date: 2000-12-12T16:11:13-05:00

Your right.  When I wrote the code that used Unchecked_Conversion,
it was on an HP-UX box with the Alsys Ada83 compiler that didn't
have System.Address_To_Access_Conversions.  The addresses there
did translate nicely to access types.

With Ada95, the only interfaces I've written to C have used the
Interfaces.C... packages.

Frank

-----Original Message-----
From: tmoran@acm.org [mailto:tmoran@acm.org]

  Instead of trying to use Unchecked_Conversion to change an address
into an access type (I presume that was meant here), use
System.Address_To_Access_Conversions.  That should work.  But a
System.Address need not be the same size as an access type (consider
various Intel memory models), and even an access to an unconstrained
array (which will involve an actual 'range being stored somewhere) and
an access to a constrained array (where the compiler might keep the
range somewhere else) may be different, and different from a
System.Address.