Re: Interfacing to C

[Georg Bauhaus <bauhaus@futureapps.de>]

Garry wrote:
 
> -- Start of hsdbg.ads
> --
> with Interfaces.C;
> with Interfaces.C.Strings;
> 
> package HSDBG is
> --  Dummy procedure?
>       type DUMB is digits 5 range 0.0 .. 1.0E10;
>       procedure DUMMY (B : DUMB);
> --  End Dummy procedure
>       procedure marktime(Variable : Interfaces.C.Strings.chars_ptr);
>       pragma Import(C, marktime, "marktime");
> end HSDBG;
> -- End of hsdbg.ads
> 

You don't need a dummy procedure, and according to the spec you do
not need a body either.
  The reason is that in general a body is there to complete
the declarations in the spec. As the only subprogram in
the spec, "marktime", is imported, there is nothing to complete
in this sense. Now to require a body, the Ada LRM has this to say
(Section 7.2)

pragma Elaborate_Body
     can be used to require a library_unit_declaration to have a body,
     ... if it would not otherwise require one.


-- Georg