anchor.diff:  	L when L#log.blocked_by =:= From ->
   	    reply(From, {error, {blocked_log, L#log.name}}, S);
   	_ ->
  -	    loop(S#state{queue = [{From, {change_header, NewHead}}
  -				  | S#state.queue]})
  -    end;
  -handle({From, {change_size, NewSize}}, S) ->
  +	    enqueue(Message, S)
  +    end;
  +handle({From, {change_size, NewSize}}=Message, S) ->
       case get(log) of
   	L when L#log.mode =:= read_only ->
   	    reply(From, {error, {read_only_mode, L#log.name}}, S);
  
positive.code: 	L when L#log.blocked_by =:= From ->
  	    reply(From, {error, {blocked_log, L#log.name}}, S);
  	_ ->
  	    loop(S#state{queue = [{From, {block, QueueLogRecs}} |
  				  S#state.queue]})
      end;
  handle({From, unblock}, S) ->
      case get(log) of
  
negative.code: 	L when L#log.blocked_by =:= From ->
  	    reply(From, {error, {blocked_log, L#log.name}}, S);
  	_ ->
  	    enqueue(Message, S)
      end;
  handle({From, {change_header, NewHead}}=Message, S) ->
      case get(log) of
  	L when L#log.mode =:= read_only ->
  	    reply(From, {error, {read_only_mode, L#log.name}}, S);
  