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

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

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:


2 Getting started

2.1 Obtaining IFI

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


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*

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

      (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

2.3 Documentation

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

HTML (Fossilized)

HTML (Standalone)


Plain text


*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:


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

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.


*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

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.


*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

      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

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

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     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.


     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.


     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

     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


     “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

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.