• How to access externally defined varibles and functions? <How_member pathlink.com> Jan 20 2006
• "Jarrett Billingsley" <kb3ctd2 yahoo.com> Jan 20 2006
• tyro[a.c.edwards] <tyro[a.c.edwards]_member pathlink.com> Jan 20 2006
• Chris Sauls <ibisbasenji gmail.com> Jan 20 2006

How to access externally defined varibles and functions? <How_member pathlink.com> writes:

What is the correct way to access externally defined variables and functions?
The following attempt result in a linker error.

Thanks,
Andrew

--------- test.d ----------

import std.cstream;
import std.process;

int global;
extern (D) void func();

void main() {
global = 12;
dout.writefln(global);
func();
dout.writefln(global);
}


--------- test2.d ----------

extern (D) int globe;

void func() {
globe = 47;
}

--------- result ----------

F:\did>dmd test test2
c:\dmd\bin\..\..\dm\bin\link.exe test+test2,,,user32+kernel32/noi;
OPTLINK (R) for Win32  Release 7.50B1
Copyright (C) Digital Mars 1989 - 2001  All Rights Reserved

test.obj(test)
Error 42: Symbol Undefined _D4test4funcFZv
--- errorlevel 1

"Jarrett Billingsley" <kb3ctd2 yahoo.com> writes:

"How to access externally defined varibles and functions?" 
<How_member pathlink.com> wrote in message 
news:dqrcnd$2n3s$1 digitaldaemon.com...

--------- test.d ----------

import std.cstream;
import std.process;

int global;

void main()
{
    global = 12;
    dout.writefln(global);
    func();
    dout.writefln(global);
}


--------- test2.d ----------

int globe;

void func()
{
    globe = 47;
}


----------------------------

And are you trying to change "global" with "func()"? 

tyro[a.c.edwards] <tyro[a.c.edwards]_member pathlink.com> writes:

In article <dqrdqj$2o13$1 digitaldaemon.com>, Jarrett Billingsley says...
"How to access externally defined varibles and functions?" 
<How_member pathlink.com> wrote in message 
news:dqrcnd$2n3s$1 digitaldaemon.com...

--------- test.d ----------

import std.cstream;
import std.process;

int global;

void main()
{
    global = 12;
    dout.writefln(global);
    func();
    dout.writefln(global);
}


--------- test2.d ----------

int globe;

void func()
{
    globe = 47;
}


----------------------------

And are you trying to change "global" with "func()"? 


Yes! I'm trying to access "global" from test.d with "func()". This solution
doesn't really work for me. Basically, I have had the pleasure of using
externally defined C functions and variables and would like to understand why
they work and how to use that facility in D.

Thanks again,
Andrew

Chris Sauls <ibisbasenji gmail.com> writes:

 What is the correct way to access externally defined variables and functions?


Simple:

########## test.d
# module test;
#
# private import std.cstream;
# private import std.process;
# private import test2;
#
# public int global;
#
# void main () {
#   global = 12;
#   dout.writefln(global);
#   func();
#   dout.writefln(global);
# }

########## test2.d
# module test2;
#
# private import test;
#
# void func () {
#   global = 47; // or // test.global = 47;
# }

-- Chris Sauls