anchor.diff:      ns_config:set(port_servers,
                     lists:keystore(PortServerName, 1, PortServers, PortConfig)).
   
  -get_port_server_param(Config, PortServerName, ParameterName) ->
  -    get_port_server_param(Config, PortServerName, ParameterName, node()).
  -
   get_port_server_param(Config, PortServerName, ParameterName, Node) ->
       StartArgs =
           case get_port_server_config(Config, PortServerName, Node) of
  
positive.code:             {PortServerName, _Path, S, _Env} -> S
          end,
      find_param(ParameterName, StartArgs).
  
  set_port_server_param(Config, PortServerName, ParameterName, V) ->
      set_port_server_param(Config, PortServerName, ParameterName, V, node()).
  
  set_port_server_param(Config, PortServerName, ParameterName, V, Node) ->
      {Path, StartArgs, Env} =
  
negative.code: 
  %% API
  -export([start_link/4, params/1,
           get_port_server_param/4,
           set_port_server_param/5]).
  
  %% gen_server callbacks
  -export([init/1,
  