anchor.diff:  @echo off
   
   set DEVICE_NAME=outline-tap0
  +set DEVICE_HWID=tap0901
   
   :: Check whether the device already exists.
   netsh interface show interface name=%DEVICE_NAME% >nul
  
positive.code: type "%BEFORE_DEVICES%"
  
  echo Creating TAP network device...
  tap-windows6\tapinstall install tap-windows6\OemVista.inf tap0901
  if %errorlevel% neq 0 (
    echo Could not create TAP network device. >&2
    exit /b 1
  
negative.code: :: us find the name of the new device.
  ::
  :: Note:
  ::  - While we could limit the search to devices having ServiceName=%DEVICE_HWID%,
  ::    that will cause wmic to output just "no instances available" when there
  ::    are no other TAP devices present, messing up the diff.
  ::  - We do not use findstr, etc., to strip blank lines because those ancient tools
  