bionic (3) et_selector.3erl.gz

NAME

       et_selector - Define event transforms and trace patterns

DESCRIPTION

EXPORTS

       make_pattern(RawPattern) -> TracePattern

              Types:

                 RawPattern = detail_level()
                 TracePattern = erlang_trace_pattern_match_spec()
                 detail_level() = min | max | integer(X) when X >= 0, X =< 100

              Makes a trace pattern suitable to feed change_pattern/1

              Min detail level deactivates tracing of calls to et:trace_me/4,5

              Max detail level activates tracing of all calls to et:trace_me/4,5

              integer(X)  detail  level  activates  tracing  of  all calls to et:trace_me/4,5 whose detail level
              argument is lesser than X.

              See also erlang:trace_pattern/2 for more info about its match_spec()

       change_pattern(Pattern) -> ok

              Types:

                 Pattern = detail_level() | empty_match_spec() | erlang_trace_pattern_match_spec()
                 detail_level() = min | max | integer(X) when X >= 0, X =< 100
                 empty_match_spec() = []

              Activates/deactivates tracing by changing the current trace pattern.

              min detail level deactivates tracing of calls to et:trace_me/4,5

              max detail level activates tracing of all calls to et:trace_me/4,5

              integer(X) detail level activates tracing of all  calls  to  et:trace_me/4,5  whose  detail  level
              argument is lesser than X.

              An empty match spec deactivates tracing of calls to et:trace_me/4,5

              Other   match   specs   activates   tracing   of   calls   to   et:trace_me/4,5  accordingly  with
              erlang:trace_pattern/2.

       parse_event(Mod, ValidTraceData) -> false | true | {true, Event}

              Types:

                 Mod   =   module_name()   |   undefined   <v>module_name()   =   atom()   <v>ValidTraceData   =
                 erlang_trace_data() | record(event)
                 erlang_trace_data() = {trace, Pid, Label, Info} | {trace, Pid, Label, Info, Extra} | {trace_ts,
                 Pid, Label, Info, ReportedTS} | {trace_ts, Pid, Label, Info, Extra, ReportedTS}  |  {seq_trace,
                 Label, Info} | {seq_trace, Label, Info, ReportedTS} | {drop, NumberOfDroppedItems}

              Transforms trace data and makes an event record out of it.

              See erlang:trace/3 for more info about the semantics of the trace data.

              An event record consists of the following fields:

                detail_level:
                  Noise has a high level as opposed to essentials.

                trace_ts:
                  Time when the trace was generated. Same as event_ts if omitted in trace data.

                event_ts:
                  Time when the event record was created.

                from:
                  From actor, such as sender of a message.

                to:
                  To actor, such as receiver of message.

                label:
                  Label intended to provide a brief event summary.

                contents:
                  All nitty gritty details of the event.

              See et:trace_me/4and et:trace_me/5 for details.

              Returns:

                {true, Event}:
                  where Event is an #event{} record representing the trace data

                true:
                  means  that  the  trace  data  already  is  an  event record and that it is valid as it is. No
                  transformation is needed.

                false:
                  means that the trace data is uninteresting and should be dropped