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IFI Fossil Interface (IFI)
1 Introduction
2 Getting started
  2.1 Obtaining IFI
  2.2 Installation
  2.3 Documentation
  2.4 Compatibility
  2.5 Staying informed
  2.6 Contributing
    2.6.1 Canonical HEmP forum
    2.6.2 Patches
    2.6.3 Fossil bundles
    2.6.4 Canonical HEmP checkin/commit access
    2.6.5 HEmP tickets
3 IFI buffers
  3.1 *Fossil shell* buffers
  3.2 The *Fossil checkouts* buffer
  3.3 The *Fossil timeline* buffer
  3.4 The *Fossil help* buffer
4 Primary features
  4.1 IFI headlines
  4.2 IFI shortcuts
5 Design features
Appendix A GNU Free Documentation License

This manual (last modified Wed 8 Sep 2021 11:13:30 BST, base
21c953800f9) documents IFI Fossil Interface (IFI) version 0.1; part of
its _pre-alpha_ development phase.

IFI Fossil Interface (IFI)
**************************

1 Introduction
**************

Fossil (https://fossil-scm.org) is a distributed software
configuration management (SCM) system with built-in HTTP server and
web interface (https://fossil-scm.org/home/doc/trunk/www/webui.wiki).

IFI provides two facilities for working with Fossil in Emacs; an
enhanced shell buffer (*note *Fossil shell* buffers::) employing
Fossil’s built-in shell (https://fossil-scm.org/home/help?cmd=shell),
and a checkouts buffer (*note The *Fossil checkouts* buffer::)
providing an overview of the current state of all Fossil checkout
directories.

The enhanced shell facility may be loaded and used independently of
the checkouts buffer facility, but the reverse is not possible.  The
checkouts buffer is dependent on one or more enhanced shells for
carrying out Fossil commands.  This is by design (*note Design
features::).

IFI does not interfere with, and does not replace, Emacs’ generic
version control interface VC (*note (emacs)Version Control::), when
Venkat Iyer’s Fossil backend is installed:

      <http://chiselapp.com/user/venks/repository/emacs-fossil>

2 Getting started
*****************

2.1 Obtaining IFI
=================

Not surprisingly, IFI’s development home is a Fossil repository known
as ‘HEmP’:

      <https://software.sebyte.me/hemp>

The copy of HEmP hosted at the above URL is known as ‘canonical HEmP’.
There you will find instructions on how to clone the repository as a
whole, as well as a link to the latest IFI release tarball.

*N.B.* HEmP includes _mulitiple_ Emacs projects.  If you decide to
clone the repository, pay attention to the ‘Anonymous quick start’
instructions found in file ‘home.md’ at the top level of branch
‘trunk’, or at the above URL.

2.2 Installation
================

Installation is the same whether you clone HEmP or download and
extract a release tarball (*note Obtaining IFI::).  In either case,
the directory containing IFI’s source files:

      ifi-ckout.el
      ifi-custom.el
      ifi-lib.el
      ifi-loaddefs.el
      ifi-shell.el
      ifi-x.el

must be added to Emacs’ ‘load-path’ before you issue the command:

      M-x load-library RET ifi-loaddefs RET

At this point, the two IFI entry point commands:

      M-x fossil-shell
      M-x fossil-checkouts

are available but the set of source files that define each command
have not been loaded (*note (elisp)Autoload::).  To load the source
files and begin using IFI, simply issue one of the above two commands.
(*Note *Fossil shell* buffers:: or *note The *Fossil checkouts*
buffer::).

To make the two IFI entry point commands available at start-up , add
the following line to your ‘.emacs’ init file:

      (require 'ifi-loaddefs)

If you prefer to load all IFI source files at start-up (rather than on
first use), add this line to your ‘.emacs’ init file instead:

      (require 'ifi-ckout)

This is sufficient because, as described in the introduction (*note
Introduction::), the checkouts buffer facility depends on the enhanced
shell facility and will ensure the shell facility is loaded.

Finally, you may load only the source files required by the enhanced
shell facility, and ensure the checkouts buffer facility is available
when it is needed, by adding these two lines to your ‘.emacs’ init
file:

      (require 'ifi-shell)
      (require 'ifi-loaddefs) ; make `M-x fossil-checkouts' available

As always, the time it takes to load Emacs Lisp source files can be
reduced by byte compiling them beforehand (*note (elisp)Byte
Compilation::).  Visit the directory containing the IFI source files
in ‘Dired’ and issue command ‘C-u 0 M-x byte-recompile-directory RET’.
The position of point is unimportant.  IFI should compile cleanly in
GNU Emacs version >= 26.3 and all later versions (*note
Compatibility::).

2.3 Documentation
=================

This manual is included in release tarballs and is available online in
the following formats:

HTML (Fossilized)
     <https://software.sebyte.me/hemp/doc/ifi/doc/>

HTML (Standalone)
     <https://software.sebyte.me/hemp/doc/ifi/doc/ifi.html>

PDF
     <https://software.sebyte.me/hemp/doc/ifi/doc/ifi.pdf>

Plain text
     <https://software.sebyte.me/hemp/doc/ifi/doc/ifi.text>

Info
     <https://software.sebyte.me/hemp/doc/ifi/doc/ifi.info>

*N.B.* The online editions of the manual document IFI’s _development_
version and may differ substantially from the editions included in a
release tarball, especially during its early development phases.
(Current phase: pre-alpha).

The easiest way to browse the Info manual in Emacs (in the absence of
an installation script) is to load Emacs library ‘Dired Extra’.
(*Note (dired-x)Top::).  With ‘Dired Extra’ loaded, simply visit the
‘doc/’ directory in ‘Dired’, position point on file ‘ifi.info’ and
type ‘Shift-I’.

2.4 Compatibility
=================

IFI development began in GNU Emacs 26.3 and is being continued in
version 27.2.  It should byte-compile cleanly, i.e.  without warnings,
in Emacs 26.3 and all later versions.

IFI has not been tested in earlier versions of GNU Emacs, nor on
platforms other than GNU/Linux.  Compilation bug reports are welcome.
*Note Contributing::.

2.5 Staying informed
====================

Stay informed about IFI development by signing up for email alerts at
canonical HEmP:

      <https://software.sebyte.me/hemp/subscribe>

You may choose between announcements, checkin (commit) alerts, forum
posts, forum edits, ticket and wiki page alerts.

*N.B.* HEmP includes _multiple_ Emacs projects.  _It is not possible
to subscribe to IFI alerts only_.

If desired, you may sign up anonymously, i.e.  without a named user
account.

2.6 Contributing
================

Contributions to IFI development should be made at canonical HEmP.
There you can post to the forum and open new tickets, anonymously if
you prefer, i.e.  without a named user account.

2.6.1 Canonical HEmP forum
--------------------------

The canonical HEmP forum is for general queries, feedback, policy
deliberation, simple patches e.t.c.

      <https://software.sebyte.me/hemp/forum>

*N.B.* HEmP includes _multiple_ Emacs projects.  The title of new
forum posts discussing IFI development should therefore begin with
IFI: .  For example:

      IFI: Issue with multiple *Fossil shell* buffers

2.6.2 Patches
-------------

Creating an ordinary patch file with Fossil is simple:

      $ fossil diff > file.patch

When posting a patch to the forum, include in the title of your post
the 10-digit artifact hash of the checkin/commit against which the
patch was made.  For example:

      IFI: Bugfix patch against 632729f34f

If you have cloned HEmP, the 10-digit artifact hash may be found
either by examining the timeline (look for the *CURRENT* entry) or by
issuing Fossil’s ‘info’ command like so:

      $ fossil info current | grep ^hash: | cut -b 15-24

If you downloaded and extracted an IFI release tarball, the 10-digit
artifact hash may be found in the ‘VERSION’ file.

Note that it is generally best to upload a patch to a pastebin and
include a link to the paste in the forum post, rather than including
the patch in the forum post itself.

2.6.3 Fossil bundles
--------------------

For more substantial contributions, the ‘diff’ command may be
inadequate since it cannnot record file renamings, file deletions, tag
operations, checkin/commit messages e.t.c.  In this case, it is better
to clone HEmP, create and work on a development branch, e.g.
‘ifi-fixes’, and then send a Fossil bundle
(https://fossil-scm.org/home/help?cmd=bundle), which you would
generate like so:

      $ fossil bundle export --branch ifi-fixes ifi-fixes.bundle

Internally, Fossil stores state information in SQLite database files,
and a Fossil bundle is no different; it’s an SQLite database file.
When attaching a Fossil bundle to an email, mime-type
application/vnd.sqlite3 should therefore be used.

Enquire in the forum for an email address or use the Fossil
administrator address fossil at domain sebyte.me).

*N.B.* For developers used to making pull or merge requests, no such
facility exists in the Fossil ecosystem.  Bundles are a powerful
alternative.

2.6.4 Canonical HEmP checkin/commit access
------------------------------------------

The first step towards gaining checkin/commit access to canonical HEmP
is to create a named user account and participate in IFI development
using the forum.

To create a named user account, visit the canonical HEmP login page
(https://software.sebyte.me/hemp/login) and click the button labelled
’Create A New Account’.

2.6.5 HEmP tickets
------------------

The canonical HEmP ticket facility is for _formal_ bug reports and
feature requests and should generally follow discussion in the forum.

      <https://software.sebyte.me/hemp/ticket>

*N.B.* HEmP includes _multiple_ Emacs projects.  The one line ticket
summary should therefore begin with IFI: .  For example:

      IFI:  Compilation error under Emacs 24.2

3 IFI buffers
*************

3.1 *Fossil shell* buffers
==========================

Once IFI has been installed (*note Installation::), you may start a
Fossil shell (and enter a *Fossil shell* buffer) by issuing command
‘M-x fossil-shell RET’.  (In fact, ‘M-x fos-sh RET’ is usually
sufficient).  This will start a ‘fossil shell’ process in whichever
directory is current when you issue the command.  (*Note (emacs)File
Names:: for a brief explanation of ‘default-directory’).

Let’s suppose that you are visiting your home directory in Dired when
you issue the command ‘M-x fossil-shell RET’.  Let’s suppose also that
your home directory is _not_ a Fossil checkout.  The ‘*Fossil shell*’
buffer will, not surprisingly, look like this:

      fossil (no repo)>

The shell is waiting for you to start issuing Fossil commands.  For
example:

      fossil (no repo)> info
      config-db:    /home/sebyte/.fossil
      fossil:       /home/sebyte/fossil/bin/fossil
      version:      2.17 [de417fb73c] 2021-08-06 07:58:18 UTC
      fossil (no repo)>

However, note the buffer’s header line in which a large red dot is
followed by the abbreviated form of the current directory.  Note also
what happens when you type a comma immediately after the Fossil
prompt; the minibuffer prompt reads Shortcut.  (*Note IFI
shortcuts::).  Let’s suppose a checkout of a newly initialised Fossil
repository is found at ‘~/fossil/sandpit/foo’ and that you type ‘cd
RET’ and enter this checkout directory.  The ‘*Fossil shell*’ buffer
would now look something like this:

      fossil (no repo)> info
      config-db:    /home/sebyte/.fossil
      fossil:       /home/sebyte/fossil/bin/fossil
      version:      2.17 [de417fb73c] 2021-08-06 07:58:18 UTC
      fossil (no repo)> [ cd ~/fossil/sandpit/foo/ ]
      fossil (unnamed)>

Behind the scenes, the previous ‘fossil shell’ process has been
killed, the current directory has changed and a new ‘fossil shell’
process has been started.  The (fake) shell command ‘cd
~/fossil/sandpit/foo/’ (delimited by brackets) records where in the
sequence of commands the change of directory occurred.

Note also the changes to the buffer’s header line.  Because the new
‘fossil shell’ process is running within a Fossil checkout, the large
red dot is now followed by the abbreviated form of the current
directory, the name of the project, the name of the current branch, a
count (in brackets) of how many checkins/commits the checkout is
behind the branch head and, finally, the default remote sync URL of
the Fossil repository to which the checkout belongs.  (*Note IFI
headlines::).

Now let’s return to your home directory in Dired and issue the command
‘M-x fossil-shell RET’ again.  We find ourselves in the same *Fossil
shell* buffer we were in before, but a second change of directory has
taken place, returning us to where we were:

      fossil (no repo)> info
      config-db:    /home/sebyte/.fossil
      fossil:       /home/sebyte/fossil/bin/fossil
      version:      2.17 [de417fb73c] 2021-08-06 07:58:18 UTC
      fossil (no repo)> [ cd ~/fossil/sandpit/foo/ ]
      fossil (unnamed)> [ cd ~/ ]
      fossil (no repo)>

The ‘*Fossil shell*’ buffer has been resued because user-cutomisable
variable ‘ifi-shell-use-multiple-buffers-p’ is bound to ‘nil’ by
default.  Had you enabled use of multiple shell buffers before issuing
the ‘M-x fossil-shell RET’ command the second time, you would have
found yourself in a new shell buffer, named ‘*Fossil shell*<2>’.

There’s no limit on how many shell buffers/processes may be alive at
once but a directory may only have a single ‘*Fossil shell*’ buffer
associated with it at any one time.

3.2 The *Fossil checkouts* buffer
=================================

Content goes here.

3.3 The *Fossil timeline* buffer
================================

Content goes here.

3.4 The *Fossil help* buffer
============================

Content goes here.

4 Primary features
******************

Content goes here.

4.1 IFI headlines
=================

Content goes here.

4.2 IFI shortcuts
=================

Content goes here.

5 Design features
*****************

Content goes here.

Appendix A GNU Free Documentation License
*****************************************

                    Version 1.3, 3 November 2008

     Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
     <http://fsf.org/>

     Everyone is permitted to copy and distribute verbatim copies
     of this license document, but changing it is not allowed.

  0. PREAMBLE

     The purpose of this License is to make a manual, textbook, or
     other functional and useful document “free” in the sense of
     freedom: to assure everyone the effective freedom to copy and
     redistribute it, with or without modifying it, either
     commercially or noncommercially.  Secondarily, this License
     preserves for the author and publisher a way to get credit for
     their work, while not being considered responsible for
     modifications made by others.

     This License is a kind of “copyleft”, which means that derivative
     works of the document must themselves be free in the same sense.
     It complements the GNU General Public License, which is a
     copyleft license designed for free software.

     We have designed this License in order to use it for manuals for
     free software, because free software needs free documentation: a
     free program should come with manuals providing the same freedoms
     that the software does.  But this License is not limited to
     software manuals; it can be used for any textual work, regardless
     of subject matter or whether it is published as a printed book.
     We recommend this License principally for works whose purpose is
     instruction or reference.

  1. APPLICABILITY AND DEFINITIONS

     This License applies to any manual or other work, in any medium,
     that contains a notice placed by the copyright holder saying it
     can be distributed under the terms of this License.  Such a
     notice grants a world-wide, royalty-free license, unlimited in
     duration, to use that work under the conditions stated herein.
     The “Document”, below, refers to any such manual or work.  Any
     member of the public is a licensee, and is addressed as “you”.
     You accept the license if you copy, modify or distribute the work
     in a way requiring permission under copyright law.

     A “Modified Version” of the Document means any work containing
     the Document or a portion of it, either copied verbatim, or with
     modifications and/or translated into another language.

     A “Secondary Section” is a named appendix or a front-matter
     section of the Document that deals exclusively with the
     relationship of the publishers or authors of the Document to the
     Document’s overall subject (or to related matters) and contains
     nothing that could fall directly within that overall subject.
     (Thus, if the Document is in part a textbook of mathematics, a
     Secondary Section may not explain any mathematics.)  The
     relationship could be a matter of historical connection with the
     subject or with related matters, or of legal, commercial,
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     The “Invariant Sections” are certain Secondary Sections whose
     titles are designated, as being those of Invariant Sections, in
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     License.  If a section does not fit the above definition of
     Secondary then it is not allowed to be designated as Invariant.
     The Document may contain zero Invariant Sections.  If the
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     The “Cover Texts” are certain short passages of text that are
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     A “Transparent” copy of the Document means a machine-readable
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     Examples of suitable formats for Transparent copies include plain
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     The “Title Page” means, for a printed book, the title page
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     the material this License requires to appear in the title page.
     For works in formats which do not have any title page as such,
     “Title Page” means the text near the most prominent appearance of
     the work’s title, preceding the beginning of the body of the
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     The “publisher” means any person or entity that distributes
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     A section “Entitled XYZ” means a named subunit of the Document
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     you modify the Document means that it remains a section “Entitled
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     The Document may include Warranty Disclaimers next to the notice
     which states that this License applies to the Document.  These
     Warranty Disclaimers are considered to be included by reference
     in this License, but only as regards disclaiming warranties: any
     other implication that these Warranty Disclaimers may have is
     void and has no effect on the meaning of this License.

  2. VERBATIM COPYING

     You may copy and distribute the Document in any medium, either
     commercially or noncommercially, provided that this License, the
     copyright notices, and the license notice saying this License
     applies to the Document are reproduced in all copies, and that
     you add no other conditions whatsoever to those of this License.
     You may not use technical measures to obstruct or control the
     reading or further copying of the copies you make or distribute.
     However, you may accept compensation in exchange for copies.  If
     you distribute a large enough number of copies you must also
     follow the conditions in section 3.

     You may also lend copies, under the same conditions stated above,
     and you may publicly display copies.

  3. COPYING IN QUANTITY

     If you publish printed copies (or copies in media that commonly
     have printed covers) of the Document, numbering more than 100,
     and the Document’s license notice requires Cover Texts, you must
     enclose the copies in covers that carry, clearly and legibly, all
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     words of the title equally prominent and visible.  You may add
     other material on the covers in addition.  Copying with changes
     limited to the covers, as long as they preserve the title of the
     Document and satisfy these conditions, can be treated as verbatim
     copying in other respects.

     If the required texts for either cover are too voluminous to fit
     legibly, you should put the first ones listed (as many as fit
     reasonably) on the actual cover, and continue the rest onto
     adjacent pages.

     If you publish or distribute Opaque copies of the Document
     numbering more than 100, you must either include a
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     state in or with each Opaque copy a computer-network location
     from which the general network-using public has access to
     download using public-standard network protocols a complete
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     use the latter option, you must take reasonably prudent steps,
     when you begin distribution of Opaque copies in quantity, to
     ensure that this Transparent copy will remain thus accessible at
     the stated location until at least one year after the last time
     you distribute an Opaque copy (directly or through your agents or
     retailers) of that edition to the public.

     It is requested, but not required, that you contact the authors
     of the Document well before redistributing any large number of
     copies, to give them a chance to provide you with an updated
     version of the Document.

  4. MODIFICATIONS

     You may copy and distribute a Modified Version of the Document
     under the conditions of sections 2 and 3 above, provided that you
     release the Modified Version under precisely this License, with
     the Modified Version filling the role of the Document, thus
     licensing distribution and modification of the Modified Version
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     these things in the Modified Version:

       A. Use in the Title Page (and on the covers, if any) a title
          distinct from that of the Document, and from those of
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          listed in the History section of the Document).  You may use
          the same title as a previous version if the original
          publisher of that version gives permission.

       B. List on the Title Page, as authors, one or more persons or
          entities responsible for authorship of the modifications in
          the Modified Version, together with at least five of the
          principal authors of the Document (all of its principal
          authors, if it has fewer than five), unless they release you
          from this requirement.

       C. State on the Title page the name of the publisher of the
          Modified Version, as the publisher.

       D. Preserve all the copyright notices of the Document.

       E. Add an appropriate copyright notice for your modifications
          adjacent to the other copyright notices.

       F. Include, immediately after the copyright notices, a license
          notice giving the public permission to use the Modified
          Version under the terms of this License, in the form shown
          in the Addendum below.

       G. Preserve in that license notice the full lists of Invariant
          Sections and required Cover Texts given in the Document’s
          license notice.

       H. Include an unaltered copy of this License.

       I. Preserve the section Entitled “History”, Preserve its Title,
          and add to it an item stating at least the title, year, new
          authors, and publisher of the Modified Version as given on
          the Title Page.  If there is no section Entitled “History”
          in the Document, create one stating the title, year,
          authors, and publisher of the Document as given on its Title
          Page, then add an item describing the Modified Version as
          stated in the previous sentence.

       J. Preserve the network location, if any, given in the Document
          for public access to a Transparent copy of the Document, and
          likewise the network locations given in the Document for
          previous versions it was based on.  These may be placed in
          the “History” section.  You may omit a network location for
          a work that was published at least four years before the
          Document itself, or if the original publisher of the version
          it refers to gives permission.

       K. For any section Entitled “Acknowledgements” or
          “Dedications”, Preserve the Title of the section, and
          preserve in the section all the substance and tone of each
          of the contributor acknowledgements and/or dedications given
          therein.

       L. Preserve all the Invariant Sections of the Document,
          unaltered in their text and in their titles.  Section
          numbers or the equivalent are not considered part of the
          section titles.

       M. Delete any section Entitled “Endorsements”.  Such a section
          may not be included in the Modified Version.

       N. Do not retitle any existing section to be Entitled
          “Endorsements” or to conflict in title with any Invariant
          Section.

       O. Preserve any Warranty Disclaimers.

     If the Modified Version includes new front-matter sections or
     appendices that qualify as Secondary Sections and contain no
     material copied from the Document, you may at your option
     designate some or all of these sections as invariant.  To do
     this, add their titles to the list of Invariant Sections in the
     Modified Version’s license notice.  These titles must be distinct
     from any other section titles.

     You may add a section Entitled “Endorsements”, provided it
     contains nothing but endorsements of your Modified Version by
     various parties—for example, statements of peer review or that
     the text has been approved by an organization as the
     authoritative definition of a standard.

     You may add a passage of up to five words as a Front-Cover Text,
     and a passage of up to 25 words as a Back-Cover Text, to the end
     of the list of Cover Texts in the Modified Version.  Only one
     passage of Front-Cover Text and one of Back-Cover Text may be
     added by (or through arrangements made by) any one entity.  If
     the Document already includes a cover text for the same cover,
     previously added by you or by arrangement made by the same entity
     you are acting on behalf of, you may not add another; but you may
     replace the old one, on explicit permission from the previous
     publisher that added the old one.

     The author(s) and publisher(s) of the Document do not by this
     License give permission to use their names for publicity for or
     to assert or imply endorsement of any Modified Version.

  5. COMBINING DOCUMENTS

     You may combine the Document with other documents released under
     this License, under the terms defined in section 4 above for
     modified versions, provided that you include in the combination
     all of the Invariant Sections of all of the original documents,
     unmodified, and list them all as Invariant Sections of your
     combined work in its license notice, and that you preserve all
     their Warranty Disclaimers.

     The combined work need only contain one copy of this License, and
     multiple identical Invariant Sections may be replaced with a
     single copy.  If there are multiple Invariant Sections with the
     same name but different contents, make the title of each such
     section unique by adding at the end of it, in parentheses, the
     name of the original author or publisher of that section if
     known, or else a unique number.  Make the same adjustment to the
     section titles in the list of Invariant Sections in the license
     notice of the combined work.

     In the combination, you must combine any sections Entitled
     “History” in the various original documents, forming one section
     Entitled “History”; likewise combine any sections Entitled
     “Acknowledgements”, and any sections Entitled “Dedications”.  You
     must delete all sections Entitled “Endorsements.”

  6. COLLECTIONS OF DOCUMENTS

     You may make a collection consisting of the Document and other
     documents released under this License, and replace the individual
     copies of this License in the various documents with a single
     copy that is included in the collection, provided that you follow
     the rules of this License for verbatim copying of each of the
     documents in all other respects.

     You may extract a single document from such a collection, and
     distribute it individually under this License, provided you
     insert a copy of this License into the extracted document, and
     follow this License in all other respects regarding verbatim
     copying of that document.

  7. AGGREGATION WITH INDEPENDENT WORKS

     A compilation of the Document or its derivatives with other
     separate and independent documents or works, in or on a volume of
     a storage or distribution medium, is called an “aggregate” if the
     copyright resulting from the compilation is not used to limit the
     legal rights of the compilation’s users beyond what the
     individual works permit.  When the Document is included in an
     aggregate, this License does not apply to the other works in the
     aggregate which are not themselves derivative works of the
     Document.

     If the Cover Text requirement of section 3 is applicable to these
     copies of the Document, then if the Document is less than one
     half of the entire aggregate, the Document’s Cover Texts may be
     placed on covers that bracket the Document within the aggregate,
     or the electronic equivalent of covers if the Document is in
     electronic form.  Otherwise they must appear on printed covers
     that bracket the whole aggregate.

  8. TRANSLATION

     Translation is considered a kind of modification, so you may
     distribute translations of the Document under the terms of
     section 4.  Replacing Invariant Sections with translations
     requires special permission from their copyright holders, but you
     may include translations of some or all Invariant Sections in
     addition to the original versions of these Invariant Sections.
     You may include a translation of this License, and all the
     license notices in the Document, and any Warranty Disclaimers,
     provided that you also include the original English version of
     this License and the original versions of those notices and
     disclaimers.  In case of a disagreement between the translation
     and the original version of this License or a notice or
     disclaimer, the original version will prevail.

     If a section in the Document is Entitled “Acknowledgements”,
     “Dedications”, or “History”, the requirement (section 4) to
     Preserve its Title (section 1) will typically require changing
     the actual title.

  9. TERMINATION

     You may not copy, modify, sublicense, or distribute the Document
     except as expressly provided under this License.  Any attempt
     otherwise to copy, modify, sublicense, or distribute it is void,
     and will automatically terminate your rights under this License.

     However, if you cease all violation of this License, then your
     license from a particular copyright holder is reinstated (a)
     provisionally, unless and until the copyright holder explicitly
     and finally terminates your license, and (b) permanently, if the
     copyright holder fails to notify you of the violation by some
     reasonable means prior to 60 days after the cessation.

     Moreover, your license from a particular copyright holder is
     reinstated permanently if the copyright holder notifies you of
     the violation by some reasonable means, this is the first time
     you have received notice of violation of this License (for any
     work) from that copyright holder, and you cure the violation
     prior to 30 days after your receipt of the notice.

     Termination of your rights under this section does not terminate
     the licenses of parties who have received copies or rights from
     you under this License.  If your rights have been terminated and
     not permanently reinstated, receipt of a copy of some or all of
     the same material does not give you any rights to use it.

  10. FUTURE REVISIONS OF THIS LICENSE

     The Free Software Foundation may publish new, revised versions of
     the GNU Free Documentation License from time to time.  Such new
     versions will be similar in spirit to the present version, but
     may differ in detail to address new problems or concerns.  See
     <http://www.gnu.org/copyleft/>.

     Each version of the License is given a distinguishing version
     number.  If the Document specifies that a particular numbered
     version of this License “or any later version” applies to it, you
     have the option of following the terms and conditions either of
     that specified version or of any later version that has been
     published (not as a draft) by the Free Software Foundation.  If
     the Document does not specify a version number of this License,
     you may choose any version ever published (not as a draft) by the
     Free Software Foundation.  If the Document specifies that a proxy
     can decide which future versions of this License can be used,
     that proxy’s public statement of acceptance of a version
     permanently authorizes you to choose that version for the
     Document.

  11. RELICENSING

     “Massive Multiauthor Collaboration Site” (or “MMC Site”) means
     any World Wide Web server that publishes copyrightable works and
     also provides prominent facilities for anybody to edit those
     works.  A public wiki that anybody can edit is an example of such
     a server.  A “Massive Multiauthor Collaboration” (or “MMC”)
     contained in the site means any set of copyrightable works thus
     published on the MMC site.

     “CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0
     license published by Creative Commons Corporation, a
     not-for-profit corporation with a principal place of business in
     San Francisco, California, as well as future copyleft versions of
     that license published by that same organization.

     “Incorporate” means to publish or republish a Document, in whole
     or in part, as part of another Document.

     An MMC is “eligible for relicensing” if it is licensed under this
     License, and if all works that were first published under this
     License somewhere other than this MMC, and subsequently
     incorporated in whole or in part into the MMC, (1) had no cover
     texts or invariant sections, and (2) were thus incorporated prior
     to November 1, 2008.

     The operator of an MMC Site may republish an MMC contained in the
     site under CC-BY-SA on the same site at any time before August 1,
     2009, provided the MMC is eligible for relicensing.

ADDENDUM: How to use this License for your documents
====================================================

To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and
license notices just after the title page:

       Copyright (C)  year  your name.
       Permission is granted to copy, distribute and/or modify this document
       under the terms of the GNU Free Documentation License, Version 1.3
       or any later version published by the Free Software Foundation;
       with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
       Texts.  A copy of the license is included in the section entitled ``GNU
       Free Documentation License''.

If you have Invariant Sections, Front-Cover Texts and Back-Cover
Texts, replace the “with...Texts.” line with this:

         with the Invariant Sections being list their titles, with
         the Front-Cover Texts being list, and with the Back-Cover Texts
         being list.

If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation.

If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of
free software license, such as the GNU General Public License, to
permit their use in free software.