Re: ATL dll failing to load in VB

From:

"Brian Muth" <bmuth@mvps.org>

Newsgroups:

microsoft.public.vc.atl

Date:

Fri, 13 Jun 2008 09:02:00 -0700

Message-ID:

<OnepR7WzIHA.4848@TK2MSFTNGP05.phx.gbl>

<pulkit.gaur@gmail.com> wrote in message news:e6b09fa3-821a-4bf7-b65b-544968011c5a@a1g2000hsb.googlegroups.com...

Hi Brian ..

Well .. my dll is in debug mode

Copied the code of the lib inside my new dll.

Now the problems boils down to the call of my wrapper dll.

i get exception saying - Access violation reading location 0x00000000
in the
dllmain() of my wrapper dll whenever it gets called.

here is the code frag ..

=====================================================
struct cInfo
{
int nCamN;
IBaseFilter *pCap;
IBaseFilter *pSG;
CoSGCB *pSGCB;
dsCallBack *pCB;
CamInfo () : pCap(NULL), pSG(NULL), pSGCB(NULL), pCB(NULL) {};
};

static __declspec( thread ) vector<cInfo> *pinfo;

BOOL APIENTRY DllMain( HMODULE hModule,
DWORD ul_reason_for_call,
LPVOID lpReserved
)
{
switch (ul_reason_for_call)
{
case DLL_PROCESS_ATTACH:
CoInitialize(0);
pinfo = new vector<cInfo>; { here i get exception }
..........
...............................
............

=======================================================
-

dinmith

I see you just posted this in the MSDN Forums at

http://forums.msdn.microsoft.com/en-US/vcgeneral/thread/c3a86583-2567-420c-9ab2-b4baea50fb6a

and I've answered it there:

You are breaking a number of rules. Please re-read the documentation on DllMain() carefully. You can only carry out very primitive
operations when attaching a DLL. And certainly there is no point in calling CoInitialize(), since the thread that loads the DLL may
not be the thread that calls into the DLL later on. Either the client must call CoInitialize, or you will have to call
CoInitialize...CoUninitialize() on each call into the DLL.