GetLastErrorAsString leaks memory

[sredna]

When using the FORMAT_MESSAGE_ALLOCATE_BUFFER flag you are supposed to LocalFree the returned string at some point.

If you are single-threaded you can do something like

LPSTR GetLastErrorAsString()
{
  UINT err = GetLastError();
  static LPSTR str = NULL;
  if (str) LocalFree(str), str = NULL;
  FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER|..., err, ..., (LPSTR) &str, ...);
  return str;
}

This will leak one string in total instead of one for each call.

If you are multi-threaded you might want to use TLS or add the strings to a list you free later...