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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Getting length of array from C
Date: 01 Feb 2005 05:26:00 +0000
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"Chuck" <cwinters15@comcast.net> writes:

> Is there some way of getting an ada array length from C interface
> code?  I have to try and accomplish this while minimizing the number
> of changes to the original Ada code.  Any ideas?

Afraid I can't tell which way round you want this to work! Do you have
an Ada array that you need C code to be able to get at, or a C array
that you need Ada code to be able to get at? What's the concept of
operation?

Typically C code needs/can provide the address of the first element of
the array and a count of the number of elements.

Depending on your compiler, you may find something like

  procedure C_Proc (A : My_Array; Count : Integer);
  pragma Import (C, C_Proc, "c_proc");

helpful. You might need to declare a derived array type to get the
representation to be compatible:

  type My_C_Array is new My_Array;
  pragma Convention (C, My_C_Array);

-- 
Simon Wright                               100% Ada, no bugs.