path: root/lib/kernel/doc/src/logger_std_h.xml

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  <header>
    <copyright>
      <year>2017</year>
      <holder>Ericsson AB. All Rights Reserved.</holder>
    </copyright>
    <legalnotice>
      Licensed under the Apache License, Version 2.0 (the "License");
      you may not use this file except in compliance with the License.
      You may obtain a copy of the License at

          http://www.apache.org/licenses/LICENSE-2.0

      Unless required by applicable law or agreed to in writing, software
      distributed under the License is distributed on an "AS IS" BASIS,
      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      See the License for the specific language governing permissions and
      limitations under the License.

    </legalnotice>

    <title>logger_std_h</title>
    <prepared></prepared>
    <responsible></responsible>
    <docno></docno>
    <approved></approved>
    <checked></checked>
    <date></date>
    <rev>A</rev>
    <file>logger_std_h.xml</file>
  </header>
  <module>logger_std_h</module>
  <modulesummary>Default handler for the Logger application.</modulesummary>

  <description>
    <p>This is the default handler for the Logger
      application. Multiple instances of this handler can be added to
      logger, and each instance will print logs to <c>standard_io</c>,
      <c>standard_error</c> or to a file.</p>

    <p>To add a new instance,
      use <seealso marker="logger#add_handler-3"><c>logger:add_handler/3</c>
      </seealso>.</p>

    <p>The handler configuration may contain the following keys,
      associated with values as described:</p>
    <taglist>
      <tag><c>filters</c></tag>
      <item>
	<p>A list of <c>{Id,{Fun,Args}}</c>, each representing a filter
	  that may selct or modify log events to forward to this
	  handler.</p></item>
      <tag><c>filter_default</c></tag>
      <item>
	<p>The atom <c>log</c> or <c>stop</c>, specifying what to
	  do with a log event if all filters
	  return <c>ignore</c>.</p></item>
      <tag><c>formatter</c></tag>
      <item>
	<p><c>{Module,Extra}</c>,
	  where <c>Module:format(Log,Extra)</c> will be called by
	  the handler to produce the string that will be printed to
	  the handler's destination.</p></item>
      <tag><c>level</c></tag>
      <item>
	<p>The level of log events that <c>logger</c> shall forward to
	  this handler. Log events of the specified, or more severe
	  levels, are forwarded.</p></item>
    </taglist>

  </description>

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  </funcs> -->

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