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Date: Mon, 14 Apr 2003 17:39:01 -0400
From: Paul Anderson <notme@nowhere.com>
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Newsgroups: comp.lang.ada
Subject: Interfacing Ada with C
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Date: 2003-04-14T17:39:01-04:00
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Hi:

I have a need to interface an Ada library with a C program.
I am having trouble finding the best way to convert
strings between the two worlds.

I have a declaration:

    procedure One(Name : in Wide_String);
    pragma Export(C, One, "one");

When I compile I get:

foo.ads:29:42: warning: type of argument "One" is unconstrained array
foo.ads:29:42: warning: foreign caller must pass bounds explicitly

Fine, except how do I "pass bounds explicitly" when I call
this function in C?  The prototype for this function in C
would normally be:

    void one(wide_string w);

which doesn't have a slot for the bounds.  So where does it
go?

Alternatively, is there an different way of doing this that
avoids this problem?

I am using gnat-3.15p.

Thanks,

Paul.