Question

I’d like to write to shared memory and then dump the contents to a file in the win32 api.
Currently I have this code:

HANDLE hFile, hMapFile;
  LPVOID lpMapAddress;

  hFile = CreateFile("input.map",
  GENERIC_READ | GENERIC_WRITE,
  0,
  NULL,
  OPEN_EXISTING,
  FILE_ATTRIBUTE_NORMAL,
  NULL);

  hMapFile = CreateFileMapping(hFile,
  NULL,
  PAGE_READWRITE,
  0,
  0,
  TEXT("SharedObject"));

  lpMapAddress = MapViewOfFile(hMapFile,
  FILE_MAP_ALL_ACCESS,
  0,
  0,
  0);

  sprintf(MapViewOfFile, "<output 1>");

  UnmapViewOfFile(lpMapAddress);
  CloseHandle(hFile);
  CloseHandle(hMapFile);

However, line 31 (the sprintf call) gives the error:

error: cannot convert `void*(*)(void*, DWORD, DWORD, DWORD, DWORD)' 
to `char*' for argument `1' to `int sprintf(char*, const char*, ...)'

I’ve tried casting the lpMapAddress to LPTSTR, but it has no effect. What am I doing wrong? Or is there a better way to do it?

Answer 1

In the

sprintf(MapViewOfFile, "<output 1>"); 

line, you wanted lpMapAddress, not MapViewOfFile. Or (char*)lpMapAddress to be precise.