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+<?xml version="1.0" encoding="latin1" ?>
+<!DOCTYPE erlref SYSTEM "erlref.dtd">
+
+<erlref>
+ <header>
+ <copyright>
+ <year>1996</year>
+ <year>2007</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>error_handler</title>
+ <prepared></prepared>
+ <docno></docno>
+ <date></date>
+ <rev></rev>
+ </header>
+ <module>error_handler</module>
+ <modulesummary>Default System Error Handler</modulesummary>
+ <description>
+ <p>The error handler module defines what happens when certain types
+ of errors occur.</p>
+ </description>
+ <funcs>
+ <func>
+ <name>undefined_function(Module, Function, Args) -> term()</name>
+ <fsummary>Called when an undefined function is encountered</fsummary>
+ <type>
+ <v>Module = Function = atom()</v>
+ <v>Args = [term()]</v>
+ <d>A (possibly empty) list of arguments <c>Arg1,..,ArgN</c></d>
+ </type>
+ <desc>
+ <p>This function is evaluated if a call is made to
+ <c>Module:Function(Arg1,.., ArgN)</c> and
+ <c>Module:Function/N</c> is undefined. Note that
+ <c>undefined_function/3</c> is evaluated inside the process
+ making the original call.</p>
+ <p>If <c>Module</c> is interpreted, the interpreter is invoked
+ and the return value of the interpreted
+ <c>Function(Arg1,.., ArgN)</c> call is returned.</p>
+ <p>Otherwise, it returns, if possible, the value of
+ <c>apply(Module, Function, Args)</c> after an attempt has been
+ made to autoload <c>Module</c>. If this is not possible, the
+ call to <c>Module:Function(Arg1,.., ArgN)</c> fails with
+ exit reason <c>undef</c>.</p>
+ </desc>
+ </func>
+ <func>
+ <name>undefined_lambda(Module, Fun, Args) -> term()</name>
+ <fsummary>Called when an undefined lambda (fun) is encountered</fsummary>
+ <type>
+ <v>Module = Function = atom()</v>
+ <v>Args = [term()]</v>
+ <d>A (possibly empty) list of arguments <c>Arg1,..,ArgN</c></d>
+ </type>
+ <desc>
+ <p>This function is evaluated if a call is made to
+ <c>Fun(Arg1,.., ArgN)</c> when the module defining the fun is
+ not loaded. The function is evaluated inside the process
+ making the original call.</p>
+ <p>If <c>Module</c> is interpreted, the interpreter is invoked
+ and the return value of the interpreted
+ <c>Fun(Arg1,.., ArgN)</c> call is returned.</p>
+ <p>Otherwise, it returns, if possible, the value of
+ <c>apply(Fun, Args)</c> after an attempt has been made to
+ autoload <c>Module</c>. If this is not possible, the call
+ fails with exit reason <c>undef</c>.</p>
+ </desc>
+ </func>
+ </funcs>
+
+ <section>
+ <title>Notes</title>
+ <p>The code in <c>error_handler</c> is complex and should not be
+ changed without fully understanding the interaction between
+ the error handler, the <c>init</c> process of the code server,
+ and the I/O mechanism of the code.</p>
+ <p>Changes in the code which may seem small can cause a deadlock
+ as unforeseen consequences may occur. The use of <c>input</c> is
+ dangerous in this type of code.</p>
+ </section>
+</erlref>
+