C / C++ / MFC

hello[3]=0;

Stefan63 wrote:

This means the compiler does have to create a local string variable on the stack, inside this function. And this particular string variable will indeed be destroyed upon return.

Microsoft wrote:

Microsoft Specific

char* DisplayInfo()
{
   char* hello = "hello!";
   return hello;
}

int _tmain(int argc, _TCHAR* argv[])
{
   char* h = DisplayInfo();
   if (strlen(h)>0)
       h[0] = 0;
	return 0;
}

The C++ Standard wrote:

The effect of attempting to modify a string literal is undefined.

The C++ Standard wrote:

An ordinary string literal has type "array of n const char"

Sauro Viti wrote:

As far as I know, the VB6 strings are unicode

Sauro Viti wrote:

and their VC correspondant is the BSTR type...

CPallini wrote:

You can ignored most of this difference, because Visual Basic will automatically convert any Unicode BSTRs to ASCII before passing them to an external function.

void __stdcall FillString(LPSTR pszString, LONG cSize)
{
   // Create a temp buffer with our string
   char buffer[] = "Hello from the C DLL!";

   // Copy our temp string to pszString
   // but check the size to make sure we have a buffer
   // big enough to hold the entire string.
   if (cSize > strlen(buffer))
      strcpy(pszString, buffer);
}

const wchar_t* HELLO = _T("Yahoooooo");
int DisplayInfoSize()
{
    return wcslen(HELLO);
}
LPCWSTR __stdcall DisplayInfo(wchar_t* hello)
{
    return wcscpy(hello, HELLO);
}

const wchar_t* HELLO = _T("Yahoooooo");
LPCWSTR __stdcall DisplayInfo()
{
    wchar_t* hello = new wchar_t*[wcslen(HELLO)+1];
    return wcscpy(hello, HELLO);
}

CListBox& GetListBoxCtrl() const {return *(CListBox*)this;}