docs: def airwires(board, showgui=0):
      'search for airwires in eagle board'
      board = Path(board).expand().abspath()
  
      file_out = tempfile.NamedTemporaryFile(suffix='.txt', delete=0)
      file_out.close()
  
      ulp = ulp_templ.replace('FILE_NAME', file_out.name)
  
      file_ulp = tempfile.NamedTemporaryFile(suffix='.ulp', delete=0)
      file_ulp.write(ulp.encode('utf-8'))
      file_ulp.close()
  
      commands = [
          'run ' + file_ulp.name,
          'quit',
      ]
      command_eagle(board, commands=commands, showgui=showgui)
  
      n = int(Path(file_out.name).text())
  
      Path(file_out.name).remove()
      Path(file_ulp.name).remove()
  
      return n