LPSTR FormatLineCallback(LPSTR szOutputBuffer,
    DWORD dwDevice, DWORD dwMsg, DWORD dwCallbackInstance, 
    DWORD dwParam1, DWORD dwParam2, DWORD dwParam3);
LPSTR FormatLineError(long lLineError, LPSTR lpszOutputBuffer);
LPSTR FormatLastError(DWORD dwLastError, LPSTR szOutputBuffer);
LPSTR FormatCommError(DWORD dwCommError, LPSTR szOutputBuffer);