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Date: Tue, 21 Feb 2006 16:52:49 +0100
From: Georg Bauhaus <bauhaus@futureapps.de>
Organization: future apps GmbH
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Newsgroups: comp.lang.ada
Subject: Re: binding to C: popen
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Date: 2006-02-21T16:52:42+01:00
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Poul-Erik Andreasen wrote:

> Yes but a C pointer is in Ada represented as system.address and i can
> not test that for O the the systems.address_image gives 0804C060 and if
> that is a stadart c value for a null-pointer things are fine, but that
> seems to be a hack.

System.Null_Address, or Interfaces.C.Strings.Null_Ptr perhaps?

You could consider writing a predicate like

  fucntion is_null(p: System.Address) return Boolean;

in order to have the comparison in one place only.

HTH,
 Georg