18> {ok, Pid} = couch_file:open("foo.txt", [create]),
18> process_info(Pid, [monitored_by, dictionary]).
[{monitored_by,[#Ref<0.3443229540.145621016.63807>]},
 {dictionary,[{couch_file_fd,{{file_descriptor,prim_file,
                                               #{handle => #Ref<0.3443229540.145621016.63807>,
                                                 owner => <0.103.0>,r_ahead_size => 0,
                                                 r_buffer => #Ref<0.3443229540.145620998.64182>}},
                              "foo.txt"}},
              {'$initial_call',{couch_file,init,1}},
              {read_timestamp,{1529,608469,122491}},
              {'$ancestors',[<0.99.0>]}]}]