<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE erlref SYSTEM "erlref.dtd"> <erlref> <header> <copyright> <year>1996</year> <year>2013</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. The Initial Developer of the Original Code is Ericsson AB. </legalnotice> <title>log_mf_h</title> <prepared>Martin Björklund</prepared> <responsible>Bjarne Dacker</responsible> <docno></docno> <approved>Bjarne Däcker</approved> <checked>Martin Björklund</checked> <date>1996-10-31</date> <rev>A</rev> <file>log_mf_h.sgml</file> </header> <module>log_mf_h</module> <modulesummary>An Event Handler which Logs Events to Disk</modulesummary> <description> <p>The <c>log_mf_h</c> is a <c>gen_event</c> handler module which can be installed in any <c>gen_event</c> process. It logs onto disk all events which are sent to an event manager. Each event is written as a binary which makes the logging very fast. However, a tool such as the <c>Report Browser</c> (<c>rb</c>) must be used in order to read the files. The events are written to multiple files. When all files have been used, the first one is re-used and overwritten. The directory location, the number of files, and the size of each file are configurable. The directory will include one file called <c>index</c>, and report files <c>1, 2, ....</c>. </p> </description> <datatypes> <datatype> <name name="args"/> <desc><p>Term to be sent to <seealso marker="gen_event#add_handler/3"> gen_event:add_handler/3</seealso>.</p></desc> </datatype> </datatypes> <funcs> <func> <name name="init" arity="3"/> <name name="init" arity="4"/> <fsummary>Initiate the event handler</fsummary> <desc> <p>Initiates the event handler. This function returns <c><anno>Args</anno></c>, which should be used in a call to <c>gen_event:add_handler(EventMgr, log_mf_h, <anno>Args</anno>)</c>. </p> <p><c><anno>Dir</anno></c> specifies which directory to use for the log files. <c><anno>MaxBytes</anno></c> specifies the size of each individual file. <c><anno>MaxFiles</anno></c> specifies how many files are used. <c><anno>Pred</anno></c> is a predicate function used to filter the events. If no predicate function is specified, all events are logged.</p> </desc> </func> </funcs> <section> <title>See Also</title> <p><seealso marker="gen_event">gen_event(3)</seealso>, rb(3) </p> </section> </erlref>