🚀 go-pugleaf

Here is a working function that uses FormatMessage to display what the 
problem reported by GetLastError is:

---------------------------
// hwnd - the parent window, use NULL if there is none
// title_text - the text that will show in the title of an error
//
//  message box.  Use "" or NULL if you do not want to
//  provide any text
//
// If GetLastError() returns zero, indicating no error, no
// error message is shown
//
// This function returns the last error number and sets
// last error in the OS to zero
//
DWORD WINAPI ShowLastError(HWND hwnd, const char *title_text)
  {
  TCHAR *err_msg;
  DWORD last_error = GetLastError();

  FormatMessage(
      FORMAT_MESSAGE_ALLOCATE_BUFFER |
          FORMAT_MESSAGE_FROM_SYSTEM,
      NULL,
      last_error,
      MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
      reinterpret_cast<LPTSTR>(&err_msg),
      0,
      NULL);

  if (title_text && *title_text)
    MessageBox(hwnd, err_msg, title_text, MB_OK);
  else
    MessageBox(hwnd, err_msg, "Error", MB_OK);

  LocalFree(err_msg);
  SetLastError(0);
  return last_error;
  }

---------------------------

.  Ed

> Jos� wrote in message
> news:hfonn3l8o175ht0j11i9d4q5msanpr6apt@4ax.com...
>
> What went wrong?
>
> _FILETIME f1;
>  FILE*han1=fopen("J:\\Projects\\test1.h","r");
>  res=GetFileTime(han1,  &f1,NULL,NULL);
>
> The file exists, han1 is not zero and the file can be read. But
> GetFileTime returns an error.
>
> I tried to find what went wrong. The help file tells me to:
>
> LPVOID lpMsgBuf;
>
> But that causes a compilation error, ("cannot convert void * to const
> char *) so I declared:
>
> char* lpMsgBuf;
>
> and it goes on:
>
> FormatMessage(
>    FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
>    NULL,     GetLastError(),
>    MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
>    (LPTSTR) &lpMsgBuf,     0,      NULL);
> MessageBox( NULL, lpMsgBuf, "GetLastError", MB_OK|MB_ICONINFORMATION);
> LocalFree( lpMsgBuf );
>
> The error message is "De ingang is ongeldig". If I set the language to
> English, no message is returned. Translated into English, it would be
> "The entry is invalid".
>
> Well, that's good to know: the entry is invalid! But what is the
> entry? And why is it invalid?