WSAStartup generates unhandled exception

[David Crow]

jimjim733 wrote:

when this is run an unhandled exception occurs

And if you remove the code, does the error go away? Yes I realize you need sockets initialized but that is a secondary problem.

"Love people and use things, not love things and use people." - Unknown

"The brick walls are there for a reason...to stop the people who don't want it badly enough." - Randy Pausch

[jimjim733]

Yeap, it goes away. Here is a copy of the InitInstance Cheers Jim

BOOL CMyApp::InitInstance()
{
// AfxEnableControlContainer();

// Standard initialization
// If you are not using these features and wish to reduce the size
//  of your final executable, you should remove from the following
//  the specific initialization routines you do not need.

#ifdef _AFXDLL
Enable3dControls(); // Call this when using MFC in a shared DLL
#else
Enable3dControlsStatic(); // Call this when linking to MFC statically
#endif

// Socket initialisation
//
WSADATA wsaData;
int iResult = WSAStartup(MAKEWORD(2,2),&wsaData);
if (iResult != NO\_ERROR) {
  OutputDebugString("Error at WSAStartup()\\r\\n");
}

CMyDlg dlg;
m\_pMainWnd = &dlg;

int nResponse = dlg.DoModal();
if (nResponse == IDOK)
{
	// TODO: Place code here to handle when the dialog is
	//  dismissed with OK
}
else if (nResponse == IDCANCEL)
{
	// TODO: Place code here to handle when the dialog is
	//  dismissed with Cancel
}

// Since the dialog has been closed, return FALSE so that we exit the
//  application, rather than start the application's message pump.
return FALSE;

}

[Mark Salsbery]

I can't see what's causing the exception, but is there a reason you're not calling the base class InitInstance()? Mark

Mark Salsbery Microsoft MVP - Visual C++ :java:

[jimjim733]

Sorry, not sure I follow....that is the base class of the project....isn't it? Am I missing something here?:confused:

[Mark Salsbery]

jimjim733 wrote:

that is the base class of the project....isn't it?

Maybe it is (I can't see the header file) but it looks so much like an MFC CWinApp/CWinAppEx InitInstance() override that I assumed it was :) Mark

Mark Salsbery Microsoft MVP - Visual C++ :java:

[jimjim733]

ok, so what do I need to do? :~

[David Crow]

When the exception is thrown, what does the call stack look like?

"Love people and use things, not love things and use people." - Unknown

"The brick walls are there for a reason...to stop the people who don't want it badly enough." - Randy Pausch

[Mark Salsbery]

Something like this:

BOOL CMyApp::InitInstance()
{
if (!CWinApp::InitInstance())
return FALSE;
// AfxEnableControlContainer();

// Standard initialization
// If you are not using these features and wish to reduce the size
//  of your final executable, you should remove from the following
//  the specific initialization routines you do not need.

#ifdef _AFXDLL
Enable3dControls(); // Call this when using MFC in a shared DLL
#else
Enable3dControlsStatic(); // Call this when linking to MFC statically
#endif

...

Not all base class implementations of virtual functions do anything but there is a little code in CWinApp::InitInstance() that may or may not be important. Mark

Mark Salsbery Microsoft MVP - Visual C++ :java:

[jimjim733]

No, that didn't work :confused:

[jimjim733]

here's a copy of the stack not sure what I am looking for??? Jim

std::vector<UnitInfoStruct *,std::allocator<UnitInfoStruct *> >::size() line 114 + 15 bytes
CAlinksRemoteControl::ScanForUnits() line 480 + 14 bytes
CMultiVueDlg::OnInitDialog() line 130
AfxDlgProc(HWND__ * 0x00240334, unsigned int 272, unsigned int 3081096, unsigned int 3081096) line 35 + 14 bytes
USER32! 7e418734()
USER32! 7e42413c()
USER32! 7e423b30()
USER32! 7e43e599()
USER32! 7e418734()
USER32! 7e418816()
USER32! 7e42a013()
USER32! 7e42a998()
CWnd::DefWindowProcA(unsigned int 272, unsigned int 3081096, long 0) line 1000 + 32 bytes
CWnd::Default() line 249
CDialog::HandleInitDialog(unsigned int 3081096, unsigned int 3081096) line 624 + 8 bytes
CWnd::OnWndMsg(unsigned int 272, unsigned int 3081096, long 0, long * 0x0012f800) line 1815 + 17 bytes
CWnd::WindowProc(unsigned int 272, unsigned int 3081096, long 0) line 1585 + 30 bytes
AfxCallWndProc(CWnd * 0x0012fc08 {CMultiVueDlg hWnd=???}, HWND__ * 0x00240334, unsigned int 272, unsigned int 3081096, long 0) line 215 + 26 bytes
AfxWndProc(HWND__ * 0x00240334, unsigned int 272, unsigned int 3081096, long 0) line 368
AfxWndProcBase(HWND__ * 0x00240334, unsigned int 272, unsigned int 3081096, long 0) line 220 + 21 bytes
USER32! 7e418734()
USER32! 7e418816()
USER32! 7e42927b()
USER32! 7e42651a()
USER32! 7e42683e()
USER32! 7e439b43()
CWnd::CreateDlgIndirect(const DLGTEMPLATE * 0x0042b540, CWnd * 0x00000000 {CWnd hWnd=???}, HINSTANCE__ * 0x00400000) line 327 + 36 bytes
CDialog::DoModal() line 531 + 32 bytes
CMultiVueApp::InitInstance() line 71 + 11 bytes
AfxWinMain(HINSTANCE__ * 0x00400000, HINSTANCE__ * 0x00000000, char * 0x00151f0c, int 1) line 39 + 11 bytes
WinMain(HINSTANCE__ * 0x00400000, HINSTANCE__ * 0x00000000, char * 0x00151f0c, int 1) line 30
WinMainCRTStartup() line 330 + 54 bytes
KERNEL32! 7c817067()

[David Crow]

jimjim733 wrote:

not sure what I am looking for???

It looks as though your code gets all the way into OnInitDialog() before the exception is thrown.

"Love people and use things, not love things and use people." - Unknown

"The brick walls are there for a reason...to stop the people who don't want it badly enough." - Randy Pausch

[Mark Salsbery]

What does "didn't work" mean? I didn't expect it to fix the exception - i only pointed out the fact that it was missing and wondered if there was a reason. Mark

Mark Salsbery Microsoft MVP - Visual C++ :java:

[Roger Stoltz]

Like David said, you seem to get as far as to OnInitDialog. Is it possible that the code using the vector doesn't run if the socket lib hasn't been initialized? That could explain why the error "goes away" if you omit the call to WSAStartup. To me it looks like the std::vector<UnitInfoStruct*> vector has not been created properly since vector::size() only operates on internal data and doesn't change anything. Could it be that the vector variable is a pointer that you haven't allocated memory for? :~ Just guessing, but it could be worth checking...

"It's supposed to be hard, otherwise anybody could do it!" - selfquote
"High speed never compensates for wrong direction!" - unknown

[jimjim733]

Sorry, just thought that might have fixed it. :(

[jimjim733]

Okay, thanks.....i'll take a look

[jimjim733]

okay, can you help? I am not sure how to do this:~ Below are the only references I have for UnitInfoStruct

struct UnitInfoStruct *pUnit = NULL;

	pUnit = new struct UnitInfoStruct;

vector<struct UnitInfoStruct \*> m\_vszIPAddr;

struct UnitInfoStruct {
char szIPAddr[16];
char szSer[9];
};

As you can tell, I am struggling with this a bit. Jim

[Roger Stoltz]

Ok, it's the m_vszIPAddr variable I'm suspicious about, or rather its container since the variable itself is not a pointer. The reason why I think this is suspicious is you get an access violation, which usually means a pointer referencing out-of-bounds memory e.g. a very low address. Since you get the assertion inside the std::vector::size() function, which only operates on internal operators that doesn't reference memory outside the vector elements if initialized properly, my guess is that somehow the vector has not been initialized properly. As the vector itself is not a pointer, it should be initialized when its container is created and that's why I'm curious about the container. In your CAlinksRemoteControl::ScanForUnits() you must access the vector in some way, probably calling push_back() to add a new "unit". I would also like to see the code for allocating memory for a new "unit", how data is assigned to it and how it is inserted into the vector.

"It's supposed to be hard, otherwise anybody could do it!" - selfquote
"High speed never compensates for wrong direction!" - unknown

[jimjim733]

One thing I have tried is moving the WSAStartup to the main initDialog function and the app goes through. Any ideas???? jim:confused:

[Roger Stoltz]

jimjim733 wrote:

Any ideas?

Nope. I suggest you follow the call chain into ScanForUnits() from OnInitDialog() in debug mode. Verify that all objects operated on are created properly.

"It's supposed to be hard, otherwise anybody could do it!" - selfquote
"High speed never compensates for wrong direction!" - unknown