<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE chapter SYSTEM "chapter.dtd">
<chapter>
<header>
<copyright>
<year>2003</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.
</legalnotice>
<title>Error Logging</title>
<prepared></prepared>
<docno></docno>
<date></date>
<rev></rev>
<file>error_logging.xml</file>
</header>
<marker id="error logging"></marker>
<section>
<title>Error Information From the Runtime System</title>
<p>Error information from the runtime system, that is, information
about a process terminating because of an uncaught error exception,
is by default written to terminal (tty):</p>
<code type="none"><![CDATA[
=ERROR REPORT==== 9-Dec-2003::13:25:02 ===
Error in process <0.27.0> with exit value: {{badmatch,[1,2,3]},[{m,f,1},{shell,eval_loop,2}]}]]></code>
<p>The error information is handled by the <em>error logger</em>, a
system process registered as <c>error_logger</c>. This process
receives all error messages from the Erlang runtime system as
well as from the standard behaviours and different Erlang/OTP
applications.</p>
<p>The exit reasons (such as <c>badarg</c>) used by
the runtime system are described in
<seealso marker="doc/reference_manual:errors#exit_reasons">
Errors and Error Handling</seealso>.</p>
<p>For information about the process <c>error_logger</c> and its user
interface (with the same name), see the
<seealso marker="kernel:error_logger">error_logger(3)</seealso>
manual page in Kernel. The system can be configured so that
error information
is written to file or to tty, or both. In addition, user-defined
applications can send and format error information using
<c>error_logger</c>.</p>
</section>
<section>
<title>SASL Error Logging</title>
<p>The standard behaviours (<c>supervisor</c>, <c>gen_server</c>,
and so on) send progress and error information to <c>error_logger</c>.
If the SASL application is started, this information is
written to tty as well. For more information, see
<seealso marker="sasl:error_logging">SASL Error Logging</seealso>
in the SASL User's Guide.</p>
<pre>
% <input>erl -boot start_sasl</input>
Erlang (BEAM) emulator version 5.4.13 [hipe] [threads:0] [kernel-poll]
=PROGRESS REPORT==== 31-Mar-2006::12:45:58 ===
supervisor: {local,sasl_safe_sup}
started: [{pid,<0.33.0>},
{name,alarm_handler},
{mfa,{alarm_handler,start_link,[]}},
{restart_type,permanent},
{shutdown,2000},
{child_type,worker}]
=PROGRESS REPORT==== 31-Mar-2006::12:45:58 ===
supervisor: {local,sasl_safe_sup}
started: [{pid,<0.34.0>},
{name,overload},
{mfa,{overload,start_link,[]}},
{restart_type,permanent},
{shutdown,2000},
{child_type,worker}]
=PROGRESS REPORT==== 31-Mar-2006::12:45:58 ===
supervisor: {local,sasl_sup}
started: [{pid,<0.32.0>},
{name,sasl_safe_sup},
{mfa,{supervisor,
start_link,
[{local,sasl_safe_sup},sasl,safe]}},
{restart_type,permanent},
{shutdown,infinity},
{child_type,supervisor}]
=PROGRESS REPORT==== 31-Mar-2006::12:45:58 ===
supervisor: {local,sasl_sup}
started: [{pid,<0.35.0>},
{name,release_handler},
{mfa,{release_handler,start_link,[]}},
{restart_type,permanent},
{shutdown,2000},
{child_type,worker}]
=PROGRESS REPORT==== 31-Mar-2006::12:45:58 ===
application: sasl
started_at: nonode@nohost
Eshell V5.4.13 (abort with ^G)
1> </pre>
</section>
</chapter>
