open_channel (Net::SSH::Connection::Session)

         # File lib/net/ssh/connection/session.rb, line 287
    287:     def open_channel(type="session", *extra, &on_confirm)
    288:       local_id = get_next_channel_id
    289:       channel = Channel.new(self, type, local_id, &on_confirm)
    290:
    291:       msg = Buffer.from(:byte, CHANNEL_OPEN, :string, type, :long, local_id,
    292:         :long, channel.local_maximum_window_size,
    293:         :long, channel.local_maximum_packet_size, *extra)
    294:       send_message(msg)
    295:
    296:       channels[local_id] = channel
    297:     end