text: #!/usr/bin/env python3
  
  # Copyright (c) 2020, G.A. vd. Hoorn
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  # author: G.A. vd. Hoorn
  
  
  """
  Write to a controller IO port.
  
  Usage: dominh [--no-upload] write [options] <host> <port_type> <index> <val>
  
  Options:
    -h --help     Show this screen.
    --check       Verify the write was successful. Exit status
                  reflects success of operation.
  
  """
  
  import sys
  
  from docopt import docopt
  from requests import exceptions
  
  import dominh
  from dominh.io import io_write
  
  
  def main(argv, skip_upload=False):
      args = docopt(__doc__, argv=argv)
  
      port_type = args['<port_type>']
      index = int(args['<index>'])
      val = int(args['<val>'])
  
      check = args['--check']
  
      try:
          c = dominh.connect(host=args['<host>'], skip_helper_upload=skip_upload)
          ret = io_write(c._conx, port_type, index, val, check=check)
          if check:
              sys.exit(ret)
  
      except (exceptions.ConnectionError, OSError) as e:
          sys.stderr.write(f"Error trying to connect to the controller: {e}\n")
      except dominh.DominhException as e:
          sys.stderr.write(f"Error during write: {e}\n")
  