Interfacing a subprogram from C.

Interfacing a subprogram from C.

[Pedro Jose Garcia Gil]

Hello.

I want to use a function in C to program in Ada95.

For example (I have included all the realized steps.):

%%%%%%%%%%%% file "pepe.c" %%%%%
#include <stdio.h>
void pintar(int a){
printf("The number is : %d \n",a);
}
%%%%%%%%%%%%

$gcc -c pepe.c

%%%%%%%%%%% file prueba.adb %%%
with Ada.Text_IO; use Ada.Text_IO;

procedure prueba is
 pragma linker_options("prueba.o");

 procedure pintar(dato: integer);
 pragma import(C,pintar,"pintar");
 a: integer:=7;

begin
 pintar(a);
end prueba;

%%%%%%%%%%%%%%

$gnatmake prueba.adb
>>>>>>>>>>>>>>>>>>>>>>>>>
gnatbind -x prueba.ali
gnatlink prueba.ali
prueba.o: In function `_ada_prueba':
prueba.o(.text+0x0): multiple definition of `_ada_prueba'
./prueba.o(.text+0x0): first defined here
./prueba.o: In function `_ada_prueba':
./prueba.o(.text+0x10): undefined reference to `pintar'
prueba.o: In function `_ada_prueba':
prueba.o(.text+0x10): undefined reference to `pintar'
gnatmake: *** link failed.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>


What am I doing wrong?.

It's necessary to compile with other options or include some file in
somewhere?.

Thank you very much.

Pedro.

Re: Interfacing a subprogram from C.

[sk]

Hi,

1) Remove  "pragma linker_options("prueba.o");" from the 
Ada source.

2) use the command "gnatmake prueba.adb -largs pepe.o"

3) READ THE GNAT MANUALS :-)


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Re: Interfacing a subprogram from C.

[Pedro Garcia Gil]

It's OK,

Thanks you very much.

Re: Interfacing a subprogram from C.

[Jerry van Dijk]

"Pedro Jose Garcia Gil" <pggil@isa.upv.es> writes:

> $gcc -c pepe.c
> What am I doing wrong?.

Your C object file is called pepe.o
 
> It's necessary to compile with other options or include some file in
> somewhere?.

More portable is:

*** c_part.c ***************************************************************
#include <stdio.h>

void c_part(int i)
{
  printf("c_part received: %d\n", i);
}
****************************************************************************

*** ada_part.adb ***********************************************************
with Interfaces.C;

procedure Ada_Part is

   procedure C_Part (I : Interfaces.C.int);
   pragma Import (C, C_Part, "c_part");
   pragma Linker_Options ("c_part.o");

begin
   C_Part (7);
end Ada_Part;
****************************************************************************

****************************************************************************
C_PART   C              87  28-02-02  19:07 c_part.c
ADA_PART ADB           213  28-02-02  19:10 ada_part.adb

C:\Home\work>gcc -c -o c_part.o c_part.c

C:\Home\work>gnatmake ada_part
gcc -c ada_part.adb
gnatbind -x ada_part.ali
gnatlink ada_part.ali

C:\Home\work>ada_part
c_part received: 7
****************************************************************************

-- 
--  Jerry van Dijk   | email: jvandyk@attglobal.net
--  Leiden, Holland  | web:   users.ncrvnet.nl/gmvdijk

Re: Interfacing a subprogram from C.

[Jeffrey Carter]

Pedro Jose Garcia Gil wrote:
> 
> Hello.
> 
> I want to use a function in C to program in Ada95.
> 
> For example (I have included all the realized steps.):
> 
> %%%%%%%%%%%% file "pepe.c" %%%%%
> #include <stdio.h>
> void pintar(int a){
> printf("The number is : %d \n",a);
> }
> %%%%%%%%%%%%
> 
> $gcc -c pepe.c
> 
> %%%%%%%%%%% file prueba.adb %%%
> with Ada.Text_IO; use Ada.Text_IO;
> 
> procedure prueba is
>  pragma linker_options("prueba.o");

I suggest you want "pepe.o" here.

> 
>  procedure pintar(dato: integer);
>  pragma import(C,pintar,"pintar");
>  a: integer:=7;
> 
> begin
>  pintar(a);
> end prueba;
> 
> %%%%%%%%%%%%%%
> 
> $gnatmake prueba.adb
> >>>>>>>>>>>>>>>>>>>>>>>>>
> gnatbind -x prueba.ali
> gnatlink prueba.ali
> prueba.o: In function `_ada_prueba':
> prueba.o(.text+0x0): multiple definition of `_ada_prueba'
> ./prueba.o(.text+0x0): first defined here
> ./prueba.o: In function `_ada_prueba':
> ./prueba.o(.text+0x10): undefined reference to `pintar'
> prueba.o: In function `_ada_prueba':
> prueba.o(.text+0x10): undefined reference to `pintar'
> gnatmake: *** link failed.
> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
> 
> What am I doing wrong?.
> 
> It's necessary to compile with other options or include some file in
> somewhere?.
> 
> Thank you very much.
> 
> Pedro.


-- 
Jeffrey Carter