dll from win32 console.

[appollosputnik]

Dear Friends I have a mfc application which I already converted to a dll. now I want to launch that application from another win32 client application. So how I can achieve this. Any h elp would be highly appreciated. check my code snippet. //in App.h header extern "C" __declspec(dllexport) void runAppli(); //in App.cpp __declspec(dllexport) void runAppli(HWND hWnd) { AFX_MANAGE_STATE(AfxGetStaticModuleState()); } //In the client console int main(int argc, char **argv) { typedef void (*EntryPointfuncPtr)(int argc, const char * argv ); HINSTANCE LoadMe; LoadMe = LoadLibrary(L"C:\\Users\\DasmahapatraS\\Projects\\Bhagavan_Cadem\\RevolutionProj\\debug\\RevolutionProj.dll"); if (LoadMe != 0) printf("LoadMe library loaded!\n"); else printf("LoadMe library failed to load!\n"); EntryPointfuncPtr LibMainEntryPoint; LibMainEntryPoint = (EntryPointfuncPtr)GetProcAddress(LoadMe,"runAppli"); return 0; } I am not able to launch with this code. Please tell me whats going wrong... My application is appearing and disappearing from the screen. Thanks a lot for any help. Sujan

[Chris Losinger]

sujandasmahapatra wrote:

My application is appearing and disappearing from the screen.

when? have you tried stepping through it in the debugger?

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[appollosputnik]

nothing is happening with debugger..its dll..... appearing and disappearing....please give me some suggestion how can i launch the dll application from console client. Thanks a lot for comments. Thanks Sujan

[Chris Losinger]

sujandasmahapatra wrote:

nothing is happening with debugger..its dll.....

have you tried stepping into the DLL code to see what it's doing? http://support.microsoft.com/kb/85221[^]

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[Lost User]

That's hardly surprising since it's a console app trying to run a Windows DLL. you also seem to have a discrepancy between the definition of your runAppli() function and its implementation.

Unrequited desire is character building. OriginalGriff

[appollosputnik]

I am able to reduce the code to this much but still its crashing... ///////////////////////////////////////////////////////////////////////////////////// int main(int argc, char **argv) { /* get handle to dll */ HINSTANCE hGetProcIDDLL = LoadLibrary(TEXT("C:\\Users\\DasmahapatraS\\Projects\\Bhagavan_Cadem\\RevolutionProj\\debug\\RevolutionProj.dll")); /* get pointer to the function in the dll*/ FARPROC lpfnGetProcessID = GetProcAddress(HMODULE (hGetProcIDDLL),"runAppli"); /* Define the Function in the DLL for reuse. This is just prototyping the dll's function. A mock of it. Use "stdcall" for maximum compatibility. */ typedef BOOL (* pICFUNC)(HINSTANCE, LPCSTR); pICFUNC MyFunction=NULL; ///* The actual call to the function contained in the dll */ BOOL intMyReturnVal = MyFunction(HMODULE (hGetProcIDDLL), "runAppli"); /* Release the Dll */ FreeLibrary(hGetProcIDDLL); return 0; } ///////////////////////////////////////////////////////////////////////////////////// __declspec(dllexport) void runAppli() { AFX_MANAGE_STATE(AfxGetStaticModuleState()); } ////////////////////////////////////////////////////////////////////////////////////

[Lost User]

First point: please use <pre> tags around your code so that it is more readable. Second point:

pICFUNC MyFunction=NULL;
///* The actual call to the function contained in the dll */
BOOL intMyReturnVal = MyFunction(HMODULE (hGetProcIDDLL), "runAppli");

how do you expect a call to a NULL address not to crash?

Unrequited desire is character building. OriginalGriff

[appollosputnik]

Now I am writing like this. int main(int argc, char **argv) { /* get handle to dll */ HINSTANCE hGetProcIDDLL = LoadLibrary(TEXT("C:\\Users\\DasmahapatraS\\Projects\\Bhagavan_Cadem\\RevolutionProj\\debug\\RevolutionProj.dll")); typedef BOOL (* pICFUNC)(HINSTANCE, LPCSTR); pICFUNC lpfnGetProcessID = (pICFUNC)GetProcAddress((HMODULE) hGetProcIDDLL,"runAppli"); ///* The actual call to the function contained in the dll */ BOOL intMyReturnVal = lpfnGetProcessID((HMODULE) hGetProcIDDLL, "runAppli"); /* Release the Dll */ FreeLibrary(hGetProcIDDLL); return 0; } ////////////////////////////////////////////////////////////////////////////////////////////////////// BOOL __declspec(dllexport) runAppli(HWND hwnd, LPCSTR lpAppName) { // Only needed if resources are accessed //AFX_MANAGE_STATE(AfxGetStaticModuleState()); ::ShowWindow(hwnd, SW_SHOW); UNREFERENCED_PARAMETER(lpAppName); return true; } Somebody suggested this piece of code. But nothing is appearing with this. My mainwindow of the dll application is not coming. Can u tell me whats wrong still in this. Thanks a lot for your help. Sujan

[Stephen Hewitt]

LoadLibrary[^] returns a HMODULE, not HINSTANCE. Alter the DLL loading to look like this:

HMODULE hDll = LoadLibrary(_T("C:\\Users\\DasmahapatraS\\Projects\\Bhagavan_Cadem\\RevolutionProj\\debug\\RevolutionProj.dll"));

Secondly, lose the cast like this (since you're now using the correct type above):

typedef BOOL (*PFUNC)(HINSTANCE, LPCSTR);
PFUNC pProc = (PFUNC)GetProcAddress(hDll, "runAppli");

Note also that I've added a _T (same as TEXT) which you left out. Now a guess at the cause of your problems: GetProcAddress[^] is failing because you're using the wrong function name by ignoring name mangling[^]. Change the DLL like this:

extern "C" BOOL __declspec(dllexport) runAppli(HWND hwnd, LPCSTR lpAppName)

Steve

[appollosputnik]

With this even its not happening stephen... _T is not compiling so I have put only the text. its compiling Now the code looks like this.. int main(int argc, char **argv) { /* get handle to dll */ HMODULE hDll = LoadLibrary(TEXT("C:\\Users\\DasmahapatraS\\Projects\\Bhagavan_Cadem\\RevolutionProj\\debug\\RevolutionProj.dll")); typedef BOOL (* ICFUNC)(HINSTANCE, LPCSTR); ICFUNC lpfnGetProcessID = (ICFUNC)GetProcAddress(hDll, "runAppli"); ///* The actual call to the function contained in the dll */ BOOL intMyReturnVal = lpfnGetProcessID(hDll, "runAppli"); /* Release the Dll */ FreeLibrary(hDll); return 0; } extern "C" BOOL __declspec(dllexport) runAppli(HWND hwnd, LPCSTR lpAppName) { // Only needed if resources are accessed //AFX_MANAGE_STATE(AfxGetStaticModuleState()); ::ShowWindow(hwnd, SW_SHOW); UNREFERENCED_PARAMETER(lpAppName); return true; }

[appollosputnik]

Now the code is looking like this ....But still application is not launching. int main(int argc, char **argv) { /* get handle to dll */ HMODULE hDll = LoadLibrary(TEXT("C:\\Users\\DasmahapatraS\\Projects\\Bhagavan_Cadem\\RevolutionProj\\debug\\RevolutionProj.dll")); typedef BOOL (* ICFUNC)(HINSTANCE, LPCSTR); ICFUNC lpfnGetProcessID = (ICFUNC)GetProcAddress(hDll, "runAppli"); ///* The actual call to the function contained in the dll */ BOOL intMyReturnVal = lpfnGetProcessID(hDll, "runAppli"); /* Release the Dll */ FreeLibrary(hDll); return 0; } /////////////////////////////////////////////////////////////////////////////////////////////////////////// extern "C" BOOL __declspec(dllexport) runAppli(HWND hwnd, LPCSTR lpAppName) { // Only needed if resources are accessed //AFX_MANAGE_STATE(AfxGetStaticModuleState()); ::ShowWindow(hwnd, SW_SHOW); UNREFERENCED_PARAMETER(lpAppName); return true; }

[Stephen Hewitt]

sujandasmahapatra wrote:

With this even its not happening stephen...
_T is not compiling so I have put only the text. its compiling

Yeah, I was wrong on that point. You don't use _T on GetProcAddress. I have modified my post to reflect this.   So it works now?

Steve

[Stephen Hewitt]

Why are you passing a HMODULE when a HWND is expected?

sujandasmahapatra wrote:

BOOL intMyReturnVal = lpfnGetProcessID(hDll, "runAppli");

sujandasmahapatra wrote:

extern "C" BOOL __declspec(dllexport) runAppli(HWND hwnd, LPCSTR lpAppName)

Steve

[appollosputnik]

With this even its not launching the application. simply returning. dll application is not launching. some more things are missing it seems. Please let me know if you're able to figure it out. Thanks for your help sujan

[appollosputnik]

typedef BOOL (* ICFUNC)(HINSTANCE, LPCSTR); ICFUNC lpfnGetProcessID = (ICFUNC)GetProcAddress(hDll, "runAppli"); ///* The actual call to the function contained in the dll */ BOOL intMyReturnVal = lpfnGetProcessID(hDll, "runAppli"); lpfnGetProcessID expects a HMODULE right...? Is it wrong. ??

[appollosputnik]

How can I get the handle from the client console and pass it to the lpfnGetProcessID .... to runAppli....With the code below I am getting run-time error. that hwnd being used without being intialized.. Please tell me how can I initialize hwnd. Thanks Sujan int main(int argc, char **argv) { HWND hwnd; /* get handle to dll */ HMODULE hDll = LoadLibrary(TEXT("C:\\Users\\DasmahapatraS\\Projects\\Bhagavan_Cadem\\RevolutionProj\\debug\\RevolutionProj.dll")); typedef BOOL (* ICFUNC)(HWND, LPCSTR); ICFUNC lpfnGetProcessID = (ICFUNC)GetProcAddress(hDll, "runAppli"); ///* The actual call to the function contained in the dll */ BOOL intMyReturnVal = lpfnGetProcessID(hwnd, "runAppli"); /* Release the Dll */ FreeLibrary(hDll); return 0; }

[Stephen Hewitt]

You're not explaining yourself very clearly but it sounds like you might be after the GetConsoleWindow function.

Steve

[appollosputnik]

extern "C" BOOL __declspec(dllexport) runAppli(HWND hwnd, LPCSTR lpAppName) { // Only needed if resources are accessed //AFX_MANAGE_STATE(AfxGetStaticModuleState()); ::ShowWindow(hwnd, SW_SHOW); UNREFERENCED_PARAMETER(lpAppName); return true; } So I need to pass hwnd to this function right..? Is it necessary to launch my dll application. I just want to launch the application.

[Stephen Hewitt]

Why don't you explain exactly what you are trying to do?

Steve

[appollosputnik]

I have made some changes in the code let me know whats wrong in this my application is not launching. int main(int argc, char **argv) { HWND hWnd=NULL; /* get handle to dll */ HMODULE hDll = LoadLibrary(TEXT("C:\\Users\\DasmahapatraS\\Projects\\Bhagavan_Cadem\\RevolutionProj\\debug\\RevolutionProj.dll")); typedef BOOL (* ICFUNC)(LPCSTR); ICFUNC lpfnGetProcessID = (ICFUNC)GetProcAddress(hDll, "runAppli"); ///* The actual call to the function contained in the dll */ BOOL intMyReturnVal = lpfnGetProcessID("runAppli"); /* Release the Dll */ FreeLibrary(hDll); return 0; } //////////////////////////////////////////////////////////////////////////////////////////////////// extern "C" BOOL __declspec(dllexport) runAppli(LPCSTR lpAppName) { // Only needed if resources are accessed //AFX_MANAGE_STATE(AfxGetStaticModuleState()); ::ShowWindow( AfxGetMainWnd()->GetSafeHwnd(), SW_SHOW); UNREFERENCED_PARAMETER(lpAppName); return true; }