function IsReservedDeviceName(DevName: string): Boolean;
const
  // List of reserved device names
  cReservedNames: array[1..22] of string = (
    'CON', 'PRN', 'AUX', 'NUL',
    'COM1', 'COM2', 'COM3', 'COM4', 'COM5', 'COM6', 'COM7', 'COM8', 'COM9',
    'LPT1', 'LPT2', 'LPT3', 'LPT4', 'LPT5', 'LPT6', 'LPT7', 'LPT8', 'LPT9'
  );
var
  I: Integer; // loops thru all reserved device names
begin
  // Get base file name, excluding path
  DevName := SysUtils.AnsiUpperCase(
   SysUtils.ExtractFileName(DevName)
  );
  Result := False;
  // Check if name is reserved
  for I := Low(cReservedNames) to High(cReservedNames) do
    if cReservedNames[I] = DevName then
    begin
      Result := True;
      Break;
    end;
end;
//delphi/2217