anchor.diff:      <<A/binary, B/binary>>.
   
   
  +f(F, A) ->
  +    lists:flatten(io_lib:format(F, A)).
  +
   %% p(F) ->
   %%     p(F, []).
   
  
positive.code:     ?REGISTRY:which_sockets(true).
  
  -spec which_sockets(FilterRule) -> [socket()] when
  	FilterRule :: 'inet' | 'inet6' |
  	'stream' | 'dgram' | 'seqpacket' |
  	'sctp' | 'tcp' | 'udp' |
  	pid() |
  
negative.code: 
  -define(SELECT_INFO(Tag, SelectHandle),
          {select_info, Tag, SelectHandle}).
  
  
  %% ===========================================================================
  %%
  