Linking Errors

[davewelsh]

I have a program that requires a dll called qcode32.dll. The program is just two files: demo.cpp and qcode32.h which has the type definition used for the dll fuction calls. I also have qcode32.lib.

The qcode32.h goes something like this:
>typedef struct { ... } POSTREC;
>void __declspec (dllimport) QCODE32(POSTREC * postrec, int parm);


and the demo.cpp goes something like this:
>#include qcode32.h
>main()
>{
>...
>QCODE32((POSTREC *)&x, y);
>...
>}


Now I can compile this by running from the command line:
>cl demo.cpp qcode32.lib


But I can't make a project that will compile. I open the .cpp in vc++ and tell it to build and then vc++ creates a default project for me. I add the .h. Then I go to project->setting->link and add qcode32.lib, but when I build I get the error:

>error LNK2001: unresolved external symbol "__declspec(dllimport) void __cdecl QCODE32(struct POSTREC *,int)" (__imp_?QCODE32@@YAXPAUPOSTREC@@H@Z)


Can anyone tell me how to set up a simple project that will compile this? (I have a larger project that I want to integrate with this dll)

 

[davewelsh]

Update:

I've sucessfully made a console application and a win32 application with the four files. Now my problem is getting it to work in an MFC application.

I used the MFC AppWizard to create a dialog-based application and I want to call the dll procedures in the CWhateverDlg class. I added: #include "qcode32.h"
to WhateverDlg.cpp and in project->settings->link, I added qcode32.lib. But I still get the error when I compile.

 

[davewelsh]

Ok. I found out that the simple projects compiled because they used .c files. If I rename them to .cpp, they don't link properly. Does anyone know why this is?

My dialog-based app uses .cpp files and I doubt I could just rename all .cpp files to .c files.