~azzar1/unity/add-show-desktop-key

1332 by David Coles
Incorporated old faq.txt into new Sphinx docs
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.. IVLE - Informatics Virtual Learning Environment
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   Copyright (C) 2007-2009 The University of Melbourne
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.. This program is free software; you can redistribute it and/or modify
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   it under the terms of the GNU General Public License as published by
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   the Free Software Foundation; either version 2 of the License, or
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   (at your option) any later version.
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.. This program is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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   GNU General Public License for more details.
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.. You should have received a copy of the GNU General Public License
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   along with this program; if not, write to the Free Software
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   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
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.. _ref-faq:
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**************************
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Frequently Asked Questions
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**************************
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This is a list of Frequently Asked Questions for IVLE. It answers questions 
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about common issues encountered when configuring or running the system.
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.. _ref-faq-how:
1385 by David Coles
Fix references in Documentation
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1332 by David Coles
Incorporated old faq.txt into new Sphinx docs
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How can I...
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============
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... change the Terms of Service notice?
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---------------------------------------
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You should customize the ToS notice at :file:`/var/lib/ivle/notices/tos.html`.
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.. _ref-faq-why:
1385 by David Coles
Fix references in Documentation
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1332 by David Coles
Incorporated old faq.txt into new Sphinx docs
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Why does...
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===========
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... Apache not restart?
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-----------------------
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Make sure no console processes are lying around (e.g. sudo killall
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python), then restart with ``sudo /etc/init.d/apache2 restart``.  If the issue
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persists, try stopping the server and starting it in two separate
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steps, so you see the errors reported by the start script.
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... IVLE dump me back to the login screen with no error when I try to login?
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----------------------------------------------------------------------------
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This is usually because IVLE can't save your session information. IVLE saves
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sessions to a sessions directory on disk. Unfortunately, this is not currently
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configurable in :file:`./setup.py` config. You need to edit the Apache config 
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file.
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Look for ``PythonOption mod_python.file_session.database_directory``. Make
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sure it is set to the place you want. Then, you need to manually make sure
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that directory exists.
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The default is :file:`/var/lib/ivle/sessions`.
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1387 by David Coles
FAQs for common error messages
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... ivle-buildjail throw an UnsafeJail exception
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------------------------------------------------
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When running :program:`ivle-buildjail` you may occasionally see an error 
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like::
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    Traceback (most recent call last):
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      File "bin/ivle-buildjail", line 158, in <module>
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        raise UnsafeJail(d)
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    __main__.UnsafeJail: /var/lib/ivle/jails/__base_build__/tmp/.ICE-unix
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This means that writable files exist in the Jail template. If left in the jail 
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then users would be able to edit a file that is shared between all jail 
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instances. The usual solution is just to remove these file from the jail build 
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directory and try again.
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... the console return 'Console Restart' messages
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-------------------------------------------------
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There are three cases where a console may be restarted:
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1. **Console Restart: The IVLE console has timed out due to inactivity**
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    The Python console process is no longer running. This is most likey due to 
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    the console process being automatically terminated due to no messages 
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    being sent or received by the console in the previous 15 minutes.
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    This message can also be triggered if the console is terminated for 
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    another reason (such as being sent :const:`SIGKILL` from the system 
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    command line or any other fatal signal).
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2. **Console Restart: CPU Time Limit Exceeded**
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   To prevent exhaustion of local system resources, Python console processes 
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   are set with an CPU Time Limit of 25 seconds of user time (time executing 
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   on the CPU rather than real "clock-on-the-wall" time).
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   This setting can be configured by changing the values associated with 
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   :const:`RLIMIT_CPU` in :file:`bin/trampoline/trampoline.c`.
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3. **Console Restart: Communication to console process lost**
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    IVLE was unable to understand a response from the console process. This 
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    will only happen if the console sends a malformed response and quite 
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    likely a bug.
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4. **Console Restart: Communication to console process reset**
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    IVLE's TCP connection to the console process was reset. May indicate 
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    network issues.
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