Re: Pointer

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Mon, 19 May 2008 10:13:48 +0000, S�bastien wrote:

>> Suggesting, n is returned from the C program:
>> 
>> with Interfaces.C;  use Interfaces.C;
>> with Interfaces.C.Strings;  use Interfaces.C.Strings;
>> 
>> function Get_It return String is
>>    procedure Internal (N : out size_t; Data : out chars_ptr);
>>    pragma Import (C, Internal, "<C-name>");
>>    Data : chars_ptr;
>>    N : size_t;
>> begin
>>    Internal (Data);
>>    return Value (N, Data);
>> end Get_It;
> 
> Yes it's exaclty what I did ... and it's exaclty what I would like to 
> avoid :-) Actually, I was looking for a pure Ada solution.

In what sense pure? Do you want to re-implement Interfaces.C.String?

> I think there is a way using an unchecked type conversion, but how to be 
> sure of the size of the System.Address?

(And how to sure about the size of Character vs. char?)

You could convert System.Address to a pointer of an Ada object using an
instance of System.Address_To_Access_Conversions.

(It seems that I don't fully understand your problem)

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de