Mixing: Qbasic & C++

[i586coder]

Hello folks,

I had many experiences around mixing languages
e.g.
qbasic <-> assembly
qbasic <-> pascal
c++ -> qbasic
c++ <-> assembly

but i failed to make mix between qbasic & C++ ( C++ <- qbasic )
i think there is one method to do that,
declare qbasic function as pascal in c++

in qbasic

Code: Select all

 function addone%(n as integer)
             addone%= n + 1
 end function

& i compiled qbasic code & generate qbtst.OBJ

in C++

Code: Select all

 extern "C"{
  int pascal addone(int);
 }

main(){
 int  foo;
  foo=addone(3);//foo must be 4
}

finally, link all .OBJ files
and compiler say:

Linker Error: Undefined symbol addone in module F:\mix.CPP


need your comments

ThankX

Cheers,
Ahmad T. Dajani

[Solar]

I don't know anything about QBasic, but I'd use objdump to list the symbols from both object files. It might be as simple as a missing underscore.

[CodeCat]

Indeed, name mangling is probably your problem. If you're using GCC you could use the -fno-leading-underscore option to GCC to make the names compatible.

[Love4Boobies]

It's nice to experiment but I'm not sure I see the reason behind all of this. If you want something more low-level than C++, there's C (also Pascal), which you already managed. Both C and Pascal support stuff like GOTOs, etc.

[i586coder]

WELL,

I got a library for qbasic "3d4qb.lib" i think
This lib include many functions around 3d (scale,rotate,...)
it's hard to start like this project form scratch since i want only some
functions from that lib in my C code
so, i decide to disassemble it,& i do it ,but huge library like this in assembly langauge is terrible to understand,isn't it

thanX again

[Combuster]

You may consider to write your code against Direct3D's math library instead. And there probably are many more libraries that do math stuff for you.

I see no real need for quickbasic other than it being totally outdated.