• Alex_Dovhal (38/38) Jun 26 2011 Hi. I try to interface D module with C one. See:
• Robert Clipsham (5/7) Jun 26 2011 extern(C) extern int myCVar;
• Alex_Dovhal (63/67) Jun 26 2011 Thanks for answer. I've already tried that, it doesn't work for some rea...
• Jimmy Cao (6/75) Jun 26 2011 It works for me like this:
• Alex_Dovhal (2/7) Jun 26 2011 Thanks.

"Alex_Dovhal" <alex_dovhal yahoo.com> writes:

Hi. I try to interface D module with C one. See:

* file test.c:
#include <stdio.h>
int c_var;
int func()
{
    c_var = 1234;
    printf("In C\n");
    printf("c_var = %d\n", c_var);
    printf("&c_var = %x\n", &c_var);
    return 0;
}

* file unit.d:
module unit;
import std.stdio;
extern(C){
    int c_var;
    int func();
}

void main()
{
    func();
    writeln("In D");
    writefln("c_var = %d", c_var);
    writefln("&c_var = %x", &c_var);
}

And compile:
    dmc -c test.c
    dmd unit.d test.obj

I'd like to call C functions and use C variables in D module.
D calls C functions just fine, but how can I use C variables?

This program outputs:
In C
c_var = 1234
&c_var = 45d004
In D
c_var = 0
&c_var = 14298c

Robert Clipsham <robert octarineparrot.com> writes:

On 26/06/2011 20:54, Alex_Dovhal wrote:
 I'd like to call C functions and use C variables in D module.
 D calls C functions just fine, but how can I use C variables?

extern(C) extern int myCVar;

-- 
Robert
http://octarineparrot.com/

"Alex_Dovhal" <alex_dovhal yahoo.com> writes:

"Robert Clipsham" <robert octarineparrot.com> wrote:
 On 26/06/2011 20:54, Alex_Dovhal wrote:
 I'd like to call C functions and use C variables in D module.
 D calls C functions just fine, but how can I use C variables?

 extern(C) extern int myCVar;

Thanks for answer. I've already tried that, it doesn't work for some reason:

* file unit2.d:
module unit;
import std.stdio;
extern(C) int func();
extern(C) extern int c_var;

void main()
{
    func();
    writeln("In D");
    writefln("c_var = %d", c_var);
    writefln("&c_var = %x", &c_var);
}

Result:
In C
c_var = 1234
&c_var = 470200
In D
object.Error: Access Violation
----------------
426DA4
426C1B
405BEB
4057E7
451099
----------------


Found workaround, but it's extreme hack:

*file test.c
#include <stdio.h>
int c_var;
//int* ref_c_var()
//{
//    return &c_var;
//}

#define

REF_DECL(int, c_var)

int func()
{
    c_var = 1234;
    printf("In C\n");
    printf("c_var = %d\n", c_var);
    printf("&c_var = %x\n", &c_var);
    return 0;
}

*file: unit1.d:
module unit;
import std.stdio;

extern(C) int func();

string C_VAR(string type, string name)
{
    return
        "extern (C) "~ type ~ "* ref_" ~ name ~ "();"~
        " " ~ "ref " ~ type ~ " " ~ name ~"(){return *ref_"~name~"();}";
}

mixin(C_VAR("int", "c_var"));

void main()
{
    func();
    writeln("In D");
    writefln("c_var = %d", c_var);
    writefln("&c_var = %x", &c_var);
}

Jimmy Cao <jcao219 gmail.com> writes:

On Sun, Jun 26, 2011 at 5:00 PM, Alex_Dovhal <alex_dovhal yahoo.com> wrote:

 "Robert Clipsham" <robert octarineparrot.com> wrote:
 On 26/06/2011 20:54, Alex_Dovhal wrote:
 I'd like to call C functions and use C variables in D module.
 D calls C functions just fine, but how can I use C variables?

 extern(C) extern int myCVar;

 Thanks for answer. I've already tried that, it doesn't work for some
 reason:

 * file unit2.d:
 module unit;
 import std.stdio;
 extern(C) int func();
 extern(C) extern int c_var;

 void main()
 {
    func();
    writeln("In D");
    writefln("c_var = %d", c_var);
    writefln("&c_var = %x", &c_var);
 }

 Result:
 In C
 c_var = 1234
 &c_var = 470200
 In D
 object.Error: Access Violation
 ----------------
 426DA4
 426C1B
 405BEB
 4057E7
 451099
 ----------------


 Found workaround, but it's extreme hack:

 *file test.c
 #include <stdio.h>
 int c_var;
 //int* ref_c_var()
 //{
 //    return &c_var;
 //}

 #define

 REF_DECL(int, c_var)

 int func()
 {
    c_var = 1234;
    printf("In C\n");
    printf("c_var = %d\n", c_var);
    printf("&c_var = %x\n", &c_var);
    return 0;
 }

 *file: unit1.d:
 module unit;
 import std.stdio;

 extern(C) int func();

 string C_VAR(string type, string name)
 {
    return
        "extern (C) "~ type ~ "* ref_" ~ name ~ "();"~
        " " ~ "ref " ~ type ~ " " ~ name ~"(){return *ref_"~name~"();}";
 }

 mixin(C_VAR("int", "c_var"));

 void main()
 {
    func();
    writeln("In D");
    writefln("c_var = %d", c_var);
    writefln("&c_var = %x", &c_var);
 }

It works for me like this:

extern(C){
   __gshared int c_var;
   int func();
}

"Alex_Dovhal" <alex_dovhal yahoo.com> writes:

"Jimmy Cao" <jcao219 gmail.com> wrote:
It works for me like this:

extern(C){
   __gshared int c_var;
   int func();
}

Thanks.