Thread: linker errors?

I am using this code:

Code:

#include "dll.h"
#include <windows.h>
#include <string.h>
#include <windows.h>
#include <objidl.h>
#include <ShlObj.h>

#if defined(_MSC_VER)
#pragma comment(lib, "ole32.lib")
#pragma comment(lib, "uuid.lib")
#endif

// CreateLink - uses the Shell's IShellLink and IPersistFile interfaces 
//              to create and store a shortcut to the specified object. 
//
// Returns the result of calling the member functions of the interfaces. 
//
// Parameters:
// lpszPathObj  - address of a buffer containing the path of the object. 
// lpszPathLink - address of a buffer containing the path where the 
//                Shell link is to be stored. 
// lpszDesc     - address of a buffer containing the description of the 
//                Shell link. 
//lpszDir       - Working Directory for the file.
HRESULT CreateLink(LPCSTR lpszPathObj, LPCSTR lpszPathLink, LPCSTR lpszDesc, LPCSTR lpszDir) 
{ 
    CoInitialize(NULL);
    HRESULT hres; 
    IShellLink* psl; 
    // Get a pointer to the IShellLink interface. 
    hres = CoCreateInstance(CLSID_ShellLink, NULL, CLSCTX_INPROC_SERVER, IID_IShellLink, (LPVOID*)&psl); 
    if (SUCCEEDED(hres)) 
    { 
        IPersistFile* ppf; 
 
        // Set the path to the shortcut target and add the description. 
        psl->SetPath(lpszPathObj); 
        psl->SetDescription(lpszDesc); 
        psl->SetWorkingDirectory(lpszDir);
 
        // Query IShellLink for the IPersistFile interface for saving the 
        // shortcut in persistent storage. 
        hres = psl->QueryInterface(IID_IPersistFile, (LPVOID*)&ppf); 
 
        if (SUCCEEDED(hres)) 
        { 
            WCHAR wsz[MAX_PATH]; 
 
            // Ensure that the string is Unicode. 
            MultiByteToWideChar(CP_ACP, 0, lpszPathLink, -1, wsz, MAX_PATH); 
			
            // Add code here to check return value from MultiByteWideChar 
            // for success.
 
            // Save the link by calling IPersistFile::Save. 
            hres = ppf->Save(wsz, TRUE); 
            ppf->Release(); 
        } 
        psl->Release(); 
    } 
    return hres; 
}
export bool makeShortCut(LPCTSTR exeName, LPCTSTR lnkName, LPCTSTR description, LPCTSTR workingDir)
{
    LPCTSTR lpszFileName = lnkName;
    LPCTSTR lpszShortcutDesc = exeName;
    LPCTSTR lpszShortcutPath = description;
    LPCTSTR pszDir= workingDir;
    return(CreateLink(lpszFileName, lpszShortcutDesc, lpszShortcutPath, pszDir));
}

and I am getting:

[Linker error] undefined reference to `CoInitialize@4'
[Linker error] undefined reference to `CoCreateInstance@20'
[Linker error] undefined reference to `IID_IPersistFile'
ld returned 1 exit status
C:\Dev-Cpp\Projects\TestDLL\Makefile.win [Build Error] [Test.dll] Error 1

I am using Dev-C++ anybody no what I did wrong?

From the Dev-C++ menu: Project -> Project Options -> Parameters tab -> Add Library or Object
Navigate to the "lib" folder within the Dev-C++ installation folder.
Add the files libole32.a and libuuid.a.

gg

Hi Codeplug!
But what these lines are doing in his code?
I think they are supposed to have the same effect?

Code:

#if defined(_MSC_VER)
#pragma comment(lib, "ole32.lib")
#pragma comment(lib, "uuid.lib")
#endif

Yes, but they are for VC++. They only run if _MSC_VER is defined and that is only defined in Visual Studio.

The only thing I can see in what you've posted so far is that you don't have a balancing CoUninitialize.

So lets see the code that's calling the dll - unless calling CoUninitialize fixes it...

gg

Originally Posted by Codeplug

The only thing I can see in what you've posted so far is that you don't have a balancing CoUninitialize.

So lets see the code that's calling the dll - unless calling CoUninitialize fixes it...

gg

CoUninitialize didn't fix it and my dll calling code isn't written in C or C++.

Write a small C/C++ app that just calls your DLL so you can rule out the DLL as the source of the issue.

gg