How I properly declare an exported function that is also used locally?

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Hi,
I have a FuncA() inside the EXE. FuncA() is called from inside the EXE and from inside a DLL. Therefore, I wrote a callback function for FuncA() so that the DLL can call to it. Hence, I need to export FuncA() so that I can get the function address from inside the DLL.

declspec(dllexport) void FuncA(){ return; }//declspec(dllexport) is to be able to get the function address.

However,
Because FuncA() is called from DLL AND from inside the EXE as well,
my problem is the declaration of funcA() inside the EXE. That declaration will be used by the functions inside the EXE.

void FuncA();//If I write it this way I get the following error:
error C2375: 'FuncA' : redefinition; different linkage

And,

declspec(dllimport) void FuncA();//If I write it this way, I get the following warning and the program hangs.
warning LNK4049: locally defined symbol _FuncA imported

How do I write the proper declaration?
Note: Windows, Visual Studio 2008, Standard-C

Posted 7-Mar-11 18:53pm

kenny00100

Updated 7-Mar-11 21:13pm

v4

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2 solutions

Solution 1

I'm not sure I understand your problem correctly, but I think you have FuncA declared inside your exe file and in your dll? And in your exe you want to be able to call both the FuncA from the exe itself and the dll?
The easiest solution seems to be to just rename one of them so they no longer conflict.

Posted 7-Mar-11 19:49pm

User 7429338

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kenny00100 8-Mar-11 3:11am

Thank you for replying,
Actually, my situation is that FuncA() is defined inside EXE. And, it is also called from functions that exist inside the EXE. Furthermore, it is called by functions outside the EXE (inside the DLL).
The above is (are) the declaration of FuncA() inside the EXE that the other functions(EXE functions) use. I cannot seem to find the write format.

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Ozer Karaagac · Accepted Answer · 2011-03-08T02:08:00

As far as I understand your comments, you need to use pre-processor directives in any hader file using to declare your function.

// in AnyHaderFile.h for FuncA() declaration
#ifdef _WITHINDLL_
declspec(dllimport) void FuncA();
#else
declspec(dllexport) void FuncA();
#endif

// in your DLL file, include it with after definition of _WITHINDLL_
#define _WITHINDLL_
#include "AnyHaderFile.h"

// in your EXE file, you just need to include without _WITHINDLL_

#include "AnyHaderFile.h"

In this particual case, the function is implemented in EXE (not in DLL unlike as usual).

I hope, I understand right.