et_viewer(3)

🌸 NAME 🌸

et_viewer — she displays a sequence chart for trace events (messages/actions) 💅

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✨ DESCRIPTION ✨

okay so bestie, real talk: this section is literally empty in the original page 😭 like the Erlang folks just hit enter and moved on. The vibe is fully carried by the NAME up top and the DATA TYPES + FUNCTIONS below. No cap. 🫶

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🦋 DATA TYPES 🦋

here's the whole cast, no skips, no cuts 💖

• actors() — [term()].
• first_key() — term().
• option() — the big one, the main character 👑:

option() ::
          {title, string()} |
          {detail_level, 0..100} |
          {is_suspended, boolean()} |
          {scale, integer()} |
          {width, integer()} |
          {height, integer()} |
          {collector_pid, pid() | undefined} |
          {active_filter, atom()} |
          {max_events, integer() | undefined} |
          {max_actors, integer() | undefined} |
          {actors, actors()} |
          {first_event, first_key()} |
          {hide_unknown, boolean()} |
          {hide_actions, boolean()} |
          {display_mode,
           all |
           {search_actors, forward | reverse, first_key(), actors()}}.

ik that union is giving menu at a fancy restaurant but every single line is load-bearing, bestie 🍓

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🔥 FUNCTIONS 🔥

🌈 file/1

file(FileName :: file:filename()) -> {ok, pid()} | {error, term()}.

start a whole new event viewer plus a matching collector, and load them up with trace events straight outta a trace file 📂✨ it's giving "bring your own data".

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💜 get_collector_pid/1

get_collector_pid(ViewerPid :: pid()) -> pid().

hand her a viewer pid, she hands you back the identifier of the collector process. that's it, that's the function, no notes 🎀

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🌸 start/0

start() -> {ok, pid()} | {error, term()}.

the simplified glow-up start of a sequence chart viewer, with global tracing already activated 💅 super convenient to use straight from the command line, like so:

erl -s et_viewer

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🦄 start/1

start(GUIorOptions) -> {ok, Viewer :: pid()} | {error, term()}
                when
                    GUIorOptions :: wx | default | Options,
                    Options :: [option() | et_collector:option()].

start of a sequence chart viewer without linking to the parent process — no invisible leash, she's independent 🫶

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⭐ start_link/1

start_link(GUIorOptions) ->
                     {ok, Viewer :: pid()} | {error, term()}
                     when
                         GUIorOptions :: wx | default | Options,
                         Options :: [option() | et_collector:option()].

start a sequence chart viewer for trace events (messages/actions) 🔥

quick note on filters, because this part matters: a filter_fun() takes an event record as its sole argument and returns false | true | {true, NewEvent}.

and if collector_pid is undefined, a brand new et_collector gets started up with these parameter settings: parent_pid, event_order, trace_global, trace_pattern, trace_port, trace_max_queue, trace_client, dict_insert and dict_delete. the new et_viewer then registers itself as an et_collector subscriber 💖

🎀 Default values 🎀

• parent_pid - self().
• title - "et_viewer".
• detail_level - max.
• is_suspended - false.
• scale - 2.
• width - 800.
• height - 600.
• collector_pid - undefined.
• event_order - trace_ts.
• active_filter - collector.
• max_actors - 5.
• actors - ["UNKNOWN"].
• first_event - first.
• hide_unknown - false.
• hide_actions - false.
• display_mode - all.

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💀 stop/1

stop(ViewerPid :: pid()) -> ok.

stops a viewer process. bye bestie, you ate 🫡✨

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and that's the whole page, fr fr 🌈💜 this gem dropped as part of Ericsson AB's et 1.8, and you're reading the et_viewer(3) manual page — go forth and chart those events, queen 👑🎀