<?xml version="1.0" encoding="latin1" ?> <!DOCTYPE erlref SYSTEM "erlref.dtd"> <erlref> <header> <copyright> <year>2002</year><year>2010</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> The contents of this file are subject to the Erlang Public License, Version 1.1, (the "License"); you may not use this file except in compliance with the License. You should have received a copy of the Erlang Public License along with this software. If not, it can be retrieved online at http://www.erlang.org/. Software distributed under the License is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the specific language governing rights and limitations under the License. </legalnotice> <title>et_selector</title> <prepared>Håkan Mattsson</prepared> <responsible>Håkan Mattsson</responsible> <docno></docno> <approved>Håkan Mattsson</approved> <checked></checked> <date></date> <rev>%VSN%</rev> <file>et_selector.xml</file> </header> <module>et_selector</module> <modulesummary>Define event transforms and trace patterns</modulesummary> <description> <p></p> </description> <funcs> <func> <name>make_pattern(RawPattern) -> TracePattern</name> <fsummary>Makes a trace pattern suitable to feed change_pattern/1</fsummary> <type> <v>RawPattern = detail_level()</v> <v>TracePattern = erlang_trace_pattern_match_spec()</v> <v>detail_level() = min | max | integer(X) when X >= 0, X =< 100</v> </type> <desc> <p>Makes a trace pattern suitable to feed change_pattern/1</p> <p>Min detail level deactivates tracing of calls to <c>et:trace_me/4,5</c></p> <p>Max detail level activates tracing of all calls to <c>et:trace_me/4,5</c></p> <p>integer(X) detail level activates tracing of all calls to <c>et:trace_me/4,5</c> whose detail level argument is lesser than X.</p> <p>See also <c>erlang:trace_pattern/2</c> for more info about its <c>match_spec()</c></p> </desc> </func> <func> <name>change_pattern(Pattern) -> ok</name> <fsummary>Activates/deactivates tracing by changing the current trace pattern</fsummary> <type> <v>Pattern = detail_level() | empty_match_spec() | erlang_trace_pattern_match_spec()</v> <v>detail_level() = min | max | integer(X) when X >= 0, X =< 100</v> <v>empty_match_spec() = [] </v> </type> <desc> <p>Activates/deactivates tracing by changing the current trace pattern.</p> <p><c>min</c> detail level deactivates tracing of calls to <c>et:trace_me/4,5</c></p> <p><c>max</c> detail level activates tracing of all calls to <c>et:trace_me/4,5</c></p> <p><c>integer(X)</c> detail level activates tracing of all calls to <c>et:trace_me/4,5</c> whose detail level argument is lesser than <c>X</c>.</p> <p>An empty match spec deactivates tracing of calls to <c>et:trace_me/4,5</c></p> <p>Other match specs activates tracing of calls to <c>et:trace_me/4,5</c> accordingly with <c>erlang:trace_pattern/2</c>.</p> </desc> </func> <func> <name>parse_event(Mod, ValidTraceData) -> false | true | {true, Event}</name> <fsummary>Transforms trace data and makes an event record out of it</fsummary> <type> <v>Mod = module_name() | undefined <v>module_name() = atom() <v>ValidTraceData = erlang_trace_data() | record(event)</v> <v>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}</v> </type> <desc> <p>Transforms trace data and makes an event record out of it.</p> <p>See <c>erlang:trace/3</c> for more info about the semantics of the trace data.</p> <p>An event record consists of the following fields:</p> <taglist> <tag><em>detail_level</em></tag> <item><p>Noise has a high level as opposed to essentials.</p></item> <tag><em>trace_ts</em></tag> <item><p>Time when the trace was generated. Same as event_ts if omitted in trace data.</p></item> <tag><em>event_ts</em></tag> <item><p>Time when the event record was created.</p></item> <tag><em>from</em></tag> <item><p>From actor, such as sender of a message.</p></item> <tag><em>to</em></tag> <item><p>To actor, such as receiver of message.</p></item> <tag><em>label</em></tag> <item><p>Label intended to provide a brief event summary.</p></item> <tag><em>contents</em></tag> <item><p>All nitty gritty details of the event.</p></item> </taglist> <p>See <c>et:trace_me/4</c>and <c>et:trace_me/5</c> for details.</p> <p>Returns:</p> <taglist> <tag><em>{true, Event}</em></tag> <item><p>where Event is an #event{} record representing the trace data</p></item> <tag><em>true</em></tag> <item><p>means that the trace data already is an event record and that it is valid as it is. No transformation is needed.</p></item> <tag><em>false</em></tag> <item><p>means that the trace data is uninteresting and should be dropped</p></item> </taglist> </desc> </func> </funcs> </erlref>