Issue in getting exception pointer in VC++ CLR project for generating dump file.

Hi,

We are working on VC++ CLR (Windows Forms) application.

We are writing a code to generate Mini dump file (using MINIDUMPWRITEDUMP in dbghelp.dll) whenever application crashes.

The code available on internet for writing mini dump file in c# generates the mini dump but without Exception code and information, because _EXCEPTION_INFORMATION was set using Marshal::GetExceptionPointers() which returns 0. We called MINIDUMPWRITEDUMP inside AppDomain::UnhandledExceptionEventHandler for this.

To get the valid exception pointer for mini dump we made following attempts with and without AppDomain::UnhandledExceptionEventHandler  –

•       Used mixed (managed and unmanaged ) dll to add SetUnhandledExceptionFilter.  Inside top level exception filter function added code to write mini dump.  Inside main the handler is set on 1^st line. But handler is not invoked on any exception. This works fine with console C# project.

// inside dll
#pragma unmanaged
LONG WINAPI ABCExceptionFilter(__in struct _EXCEPTION_POINTERS *pExceptionInfo)
{ // code to write dump 
}
#pragma managed
Namespacee SEHHandler {
	public ref class SEHExpHandler
	{
	public:
		static void AddHandler()
		{
                     SetUnhandledExceptionFilter(ABCExceptionFilter);
		}
	};
}
// inside app main()
[STAThreadAttribute]
int main(array<System::String ^> ^args)
{
SEHHandler::SEHExpHandler::AddHandler();
//some code . . .
		Application::Run(gcnew Form1());
//some code . . .
}

•       Used __try __except inside application main. The exception filter was written in other C++ dll and called inside __except ( expression ) using platform Invoke.  But this throws the caught exception while trying to call handler.

// inside app class
[DllImport("SEHhandler.dll")]
extern int __stdcall se_handler(unsigned int code, IntPtr ep);

[STAThreadAttribute]
int main(array<System::String ^> ^args)
{
 __try
 { //some code. . .
 }
  __except(se_handler(GetExceptionCode(),    
 (IntPtr)GetExceptionInformation()))
 { //some code. . .
 }
}
// inside dll
 __declspec(dllexport)
  extern int WINAPI se_handler(unsigned int code, 
   struct _EXCEPTION_POINTERS* ep)
 {	// code to write minidump
		return EXCEPTION_EXECUTE_HANDLER;
 }

Can anyone help us to get either of the code work. The aim is to write dump file with correct stack trace where exception was thrown.

Thanks in advance.

-- Sumit