message: Check null pointer before fclose
  * Check null pointer before fclose, because fclose(NULL) will lead to undefined behavior
  * Update main.cpp
  Cast to one code style
  * Update main.cpp
  Remove redundant ==
diff: @@ -70,7 +70,10 @@ int __cdecl wmain(int argc, wchar_t* argv[])
  fGotChar = GetChar(&wch);
  }
  + if (hFile)
  + {
  fclose(hFile);
  + }
  wprintf(L"Done.\r\n");
  }
  