Source

xemacs-21.4 / etc / BETA

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				-*- mode:outline -*-

* Introduction
==============

You are running a potentially unstable version of XEmacs.  Please do
not report problems with Beta XEmacs to comp.emacs.xemacs.  Report
them to <xemacs-beta@xemacs.org>, preferably with 
'M-x report-xemacs-bug RET'. 

** Mailing Lists
================

*** XEmacs Beta Mailing List
----------------------------

If you are not subscribed to the XEmacs beta list you should be.
Currently all discussion of development issues, including bug reports
and coding discussion, takes place on the XEmacs Beta mailing list.
Only patches and administrative actions regarding patches are sent
elsewhere (to the XEmacs Patches list).

*** XEmacs Patches Mailing List
-------------------------------

XEmacs Patches records proposed changes to XEmacs, and their
disposition.  It is open subscription, and all patches that are
seriously proposed for inclusion in XEmacs should be posted here.  You
can follow progress of your patch by subscribing to the mailing list
or in the archives.

Besides patches, only actions by members of the XEmacs Review Board
should be posted to this list.  All discussion should be redirected to
XEmacs Beta or XEmacs Design.

*** XEmacs Design Mailing List
------------------------------

XEmacs Design is for design discussions such as adding major features
or whole modules, or reimplementation of existing functions, to XEmacs.

*** List Administrivia
----------------------

In the descriptions below, the word LIST (all uppercase) is a
variable.  Substitute "beta", "design", or "patches" as appropriate
(to get "xemacs-beta" as the mailbox for the XEmacs Beta mailing list,
or <http://www.xemacs.org/Lists/#xemacs-beta> for its URL).

The XEmacs mailing lists are managed by the Mailman mailing list
package, and the usual Mailman commands work.  Do not send mailing
list requests to the main address (<xemacs-LIST@xemacs.org>), always
send them to <xemacs-LIST-request@xemacs.org>.  If you have problems
with the list itself, they should be brought to the attention of the
XEmacs Mailing List manager <list-manager@xemacs.org> (the same
mailbox, "list-manager", for all lists).  All public mailing lists
have searchable archives.  The URL is

	     http://list-archive.xemacs.org/xemacs-LIST

Note that the xemacs-LIST-admin address is used internally by the
Mailman software; it is NOT a synonym for xemacs-LIST-request.

*** Managing your subscription via the Web
------------------------------------------

Subscription, unsubscription, and options (such as digests and
temporarily suspending delivery) can be accomplished via the web
interface at <http://www.xemacs.org/Lists/#xemacs-LIST>.

*** Subscribing by e-mail
-------------------------

Send an email message to <xemacs-LIST-request@xemacs.org> with
`subscribe' (without the quotes) as the BODY of the message.

*** Unsubscribing by e-mail
---------------------------

Send an email message to <xemacs-LIST-request@xemacs.org> with
`unsubscribe' (without the quotes) as the BODY of the message.

** Beta Release Schedule
========================

We would like to achieve a weekly or fortnightly release cycle (you
know the Open Source model: release early, release often), and in a
perfect world that would indeed be the case.  There are at least three
things that often get in the way of that goal: 1) The Release Manager
has a life outside of XEmacs (hard to believe, I know, but true), 
2) we like to make releases that will build (at least on the Release
Manager's box), and 3) Murphy likes to throw a spanner in the works
right when you least expect it (Murphy's Law: Whatever can go wrong,
will go wrong).

If you'd like to keep right up to date and ride the bleeding edge, use
CVS (see <http://www.xemacs.org/Develop/cvsaccess.html>).  If you
can't use CVS for some reason and must use FTP, please let us know.
it will make it more likely that we release betas more often.


** Reporting Problems
=====================

The best way to get problems fixed in XEmacs is to submit good problem
reports, 'M-x report-xemacs-bug RET' will help you do this (assuming
you have a usable XEmacs).  Since this is beta software, problems are
certain to exist.  Please read through all of part II of the XEmacs
FAQ for an overview of problem reporting.  Other items which are most
important are:

1.  Do not submit C stack backtraces without line numbers.  Since it
    is possible to compile optimized with debug information with GCC
    it is never a good idea to compile XEmacs without the -g flag.
    XEmacs runs on a variety of platforms, and often it is not
    possible to recreate problems which afflict a specific platform.
    The line numbers in the C stack backtrace help isolate where the
    problem is actually occurring.
 
2.  Attempt to recreate the problem starting with an invocation of
    XEmacs with `xemacs -no-autoloads'.  Quite often, problems are
    due to package interdependencies, and the like.  An actual bug
    in XEmacs should be reproducible in a default configuration
    without loading any special packages (or the one or two specific
    packages that cause the bug to appear).  If you have trouble
    getting anything to work at all with the above invocation, use
    `xemacs -vanilla' instead.  If you need to load your user init
    file or the site file to get the problem to occur, then it has
    something to do with them, and you should try to isolate the
    issue in those files.

3.  A picture can be worth a thousand words.  When reporting an
    unusual display, it is generally best to capture the problem in a
    screen dump and include that with the problem report.  The easiest
    way to get a screen dump is to use the xv program and its grab
    function.  Save the image as a GIF to keep bandwidth requirements
    down without loss of information.  MIME is the preferred method
    for making the image attachments.

** Getting the Source
=====================

In addition to the normal tar distribution, XEmacs source is now
available via CVS.  Please see

	    http://www.xemacs.org/Develop/cvsaccess.html

* Compiling Beta XEmacs
=======================

** Building an XEmacs from patches
==================================

All beta releases of XEmacs are included with patches from the previous
version in an attempt to keep bandwidth requirements down.  Patches
should be applied with the GNU patch program in something like the
following.  Let's say you're upgrading XEmacs 21.5-beta9 to XEmacs
21.5-beta10 and you have a full unmodified XEmacs 21.5-beta9 source
tree to work with.  Change to the top level directory and issue the
shell command:

$ gunzip -c /tmp/xemacs-21.5.9-21.5.10.patch.gz | patch -p1

After patching, check to see that no patches were missed by doing
$ find . -name \*.rej -print

Any rejections should be treated as serious problems to be resolved
before building XEmacs.

After seeing that there were no rejections, issue the commands

$ ./config.status --recheck
$ make beta > ./beta.err 2>&1
$ make check > ./xemacs-make-check.err 2>&1

Redirect the output from make to those files because you'll use them
later when you send off a build report with 'M-x build-report RET'

** Building XEmacs from a full distribution
===========================================

Locate a convenient place where you have at least 100MB of free space
and issue the command

$ gunzip -c /tmp/xemacs-21.5.10.tar.gz | tar xvf -

(or simply `tar zxvf /tmp/xemacs-21.5.10.tar.gz' if you use GNU tar).

cd to the top level directory and issue an appropriate configure
command.  One maintainer uses the following at the time of this
writing:

./configure \
	--extra-verbose \
	--site-prefixes=/usr/local/pgsql:/usr/local/BerkeleyDB.4.1 \
	--dynamic=yes --with-gtk=no --with-gnome=no --with-toolbars \
	--with-wmcommand --with-athena=next --with-menubars=lucid \
	--with-scrollbars=athena --with-dialogs=athena --with-widgets=athena \
	--with-gif --with-sound=native,noesd --with-site-lisp=no \
	--with-site-modules --pdump --with-mule --with-xfs --debug \
	--error-checking=all --memory-usage-stats --use-kkcc \
	--with-clash-detection

Part of the configure output is a summary that looks something
like the following.  (this summary is also available as the file
'Installation' in the top directory of your build tree, and via
the command 'M-x describe-installation RET').

uname -a: Linux eicq 2.4.20 #1 Wed Dec 18 02:14:29 EST 2002 i586 unknown

./configure  '--extra-verbose' '--site-prefixes=/usr/local/pgsql:/usr/local/BerkeleyDB.4.1' '--dynamic=yes' '--with-gtk=no' '--with-gnome=no' '--with-toolbars' '--with-wmcommand' '--with-athena=next' '--with-menubars=lucid' '--with-scrollbars=athena' '--with-dialogs=athena' '--with-widgets=athena' '--with-gif' '--with-sound=native,noesd' '--with-site-lisp=no' '--with-site-modules' '--pdump' '--with-mule' '--with-xfs' '--debug' '--error-checking=all' '--memory-usage-stats' '--use-kkcc' '--with-clash-detection'


XEmacs 21.5-b10 "burdock" (+CVS-20030131) configured for `i586-pc-linux'.


Compilation / Installation:
  Source code location:              /usr/local/src/xemacs
  Installation prefix:               /usr/local
  Additional prefixes:               /usr/local/pgsql /usr/local/BerkeleyDB.4.1
  Operating system description file: `s/linux.h'
  Machine description file:          `m/intel386.h'
  Compiler:                          gcc -Wall -Wno-switch -Winline -Wmissing-prototypes -Wsign-compare -Wundef -Wstrict-prototypes -Wshadow -Wmissing-declarations -O1 -ggdb3 -Wall -Wchar-subscripts -Wunused -Wundef -Wshadow -Wsign-compare -Wmissing-declarations -march=k6
  Relocating allocator for buffers:  no
  GNU version of malloc:             yes
    - Using Doug Lea's new malloc from the GNU C Library.

Window System:
  Compiling in support for the X window system:
    - X Windows headers location:                 /usr/X11/include
    - X Windows libraries location:               /usr/X11/lib
    - Handling WM_COMMAND properly.
  Compiling in support for the Athena widget set:
    - Athena headers location:                    X11/neXtaw
    - Athena library to link:                     neXtaw
  Using Lucid menubars.
  Using Athena scrollbars.
  Using Athena dialog boxes.
  Using Athena native widgets.

TTY:
  Compiling in support for ncurses.
  Compiling in support for GPM (General Purpose Mouse).

Images:
  Compiling in support for GIF  images (builtin).
  Compiling in support for XPM  images.
  Compiling in support for PNG  images.
  Compiling in support for JPEG images.
  Compiling in support for TIFF images.
  Compiling in support for X-Face message headers.

Sound:
  Compiling in support for sound (native).

Databases:
  Compiling in support for Berkeley database.
  Compiling in support for PostgreSQL.
    - Using PostgreSQL header file:  libpq-fe.h
    - Using PostgreSQL V7 bindings.

Internationalization:
  Compiling in support for Mule (multi-lingual Emacs).
  Compiling in support for XIM (X11R5+ I18N input method).
    - Using raw Xlib to provide XIM support.
    - Using XFontSet to provide bilingual menubar.

Mail:
  Compiling in support for "dot-locking" mail spool file locking method.

Other Features:
  Inhibiting IPv6 canonicalization at startup.
  Compiling in support for dynamic shared object modules.
  Using the new GC algorithms.
  Using the new portable dumper.
  Compiling in support for extra debugging code.
  WARNING: ---------------------------------------------------------
  WARNING: Compiling in support for runtime error checking.
  WARNING: XEmacs will run noticeably more slowly as a result.
  WARNING: Error checking is on by default for XEmacs beta releases.
  WARNING: ---------------------------------------------------------



Then...

$ make > ./beta.err 2>&1
$ make check > ./xemacs-make-check.err 2>&1

...and you should have a working XEmacs.

After you have verified that you have a functional editor, fire up
your favorite mail program and send a build report to
<xemacs-buildreports@xemacs.org>.

Preferably this is best done from XEmacs, following these simple steps:

M-x customize-group RET build-report RET
M-x build-report RET

See also
<http://www.xemacs.org/Releases/Public-21.2/tester.html#reporting>

If you create the report manually by other means, here is what the
build report should include:

1. Your hardware configuration (OS version, etc.)

2. Version numbers of software in use (X11 version, system library
   versions if appropriate, graphics library versions if appropriate).
   If you're on a system like Linux, include all the version numbers
   you can because chances are it makes a difference.

3. The options given to configure

4. The configuration report illustrated above

   For convenience all of the above items are placed in a file called
   `Installation' in the top level build directory.  They are also
   available by performing M-x describe-installation inside XEmacs.

5. Any other unusual items you feel should be brought to the attention
   of the developers.


* Packages
==========

[Note: these instructions have been partly updated, but not carefully
reviewed in some time.  Caveat tester.]

Starting with XEmacs 21.1, much of the functionality of XEmacs has
been unbundled into "the packages."  For more information about the
package system, see the Info nodes on Packages (in the XEmacs User
Manual) and on Packaging (in the Lisp Reference).

When bootstrapping XEmacs, you may need to manually install some
packages (at least xemacs-base and efs).  These packages are available
by FTP at <ftp://ftp.xemacs.org/pub/xemacs/packages/>.

** Binary package installation
==============================

Prerequisite:  XEmacs 21.0-b1.

Binary packages are complete entities that can be untarred at the top
level of an XEmacs package hierarchy and work at runtime.  To install files
in this directory, run the command `M-x package-admin-add-binary-package'
and fill in appropriate values to the prompts.

** Manual procedures for package management
===========================================

Prerequisite: XEmacs 21.0

When adding and deleting files from a lisp directory the
auto-autoloads.el (global symbols) and custom-load.el (Customization
groups) must be kept in synch.  Assuming one is manipulating a
directory called `lisp-utils', the command to rebuild the
auto-autoloads.el file is:

xemacs -vanilla -batch \
  -eval \("setq autoload-package-name \"lisp-utils\""\) \
  -f batch-update-directory lisp-utils

The command to rebuild the custom-load.el file is:

xemacs -vanilla -batch -f Custom-make-dependencies lisp-utils

To byte-compile both of these files the command is:

xemacs -vanilla -batch -f batch-byte-compile \
	lisp-utils/auto-autoloads.el lisp-utils/custom-load.el

Of course, being a beta tester, you'd be aware that it is much easier
to manage your XEmacs packages with PUI.

** Building XEmacs and XEmacs packages from scratch
===================================================

To build everything completely from scratch isn't hard, just time
consuming. 

*** Step 1 - grab the sources (core and packages)

$ cvs -d :pserver:cvs@cvs.xemacs.org:/pack/xemacscvs login
 [password: "cvs" (sans quotes)]

$ cvs -d :pserver:cvs@cvs.xemacs.org:/pack/xemacscvs co -d xemacs-21.5 xemacs

$ cvs -d :pserver:cvs@cvs.xemacs.org:/pack/xemacscvs co packages

*** Step 2 - build XEmacs

$ cd xemacs-21.5
$ ./configure [options...]
$ make > ./beta.err 2>&1
$ make check > ./xemacs-make-check.err 2>&1

And optionally:

$ make install > ./xemacs-make-install.err 2>&1

*** Step 3 - build and install the packages

$ cd packages
$ cp Local.rules.template Local.rules

Then edit Local.rules to suit your needs/environment
see: (Info-goto-node "(xemacs)Local.rules file") for details about
this file.

And then:

$ make install

* Improving XEmacs
=================

** Creating patches for submission
==================================

All patches to XEmacs that are seriously proposed for inclusion (eg,
bug fixes) should be mailed to <xemacs-patches@xemacs.org>.  Each
patch will be reviewed by the patches review board, and will be
acknowledged and added to the distribution, or rejected with an
explanation.  Progress of the patch is tracked on the XEmacs Patches
mailing list, which is open subscription.  (If a patch is simply
intended to facilitate discussion, "I mean something that works like
this but this is really rough", a Cc to XEmacs Patches is optional,
but doesn't hurt.)

Patches to XEmacs Lisp packages should be sent to the maintainer of
the package.  If the maintainer is listed as `XEmacs Development Team'
patches should be sent to <xemacs-patches@xemacs.org>.

Emailed patches should preferably be sent in MIME format and quoted
printable encoding (if necessary).

The simplest way to create well-formed patches is to use CVS and
Didier Verna's Patcher library (available as patcher.el in the
xemacs-devel package).  Patcher is new and requires some setup, but
most of the core developers are now using it for their own patches.
Patcher also can be configured to create patches for several projects,
and recognize the project from the directory it is invoked in.  This
makes it a useful general tool (as long as XEmacs-style patches are
accepted at your other projects, which is likely since they conform to
the GNU standards).

When making patches by hand, please use the `-u' option, or if your
diff doesn't support it, `-c'.  Using ordinary (context-free) diffs
are notoriously prone to error, since line numbers tend to change when
others make changes to the same source file.

An example of the `diff' usage:

$ diff -u OLDFILE NEWFILE

-or-

$ diff -c OLDFILE NEWFILE

Also, it is helpful if you create the patch in the top level of the
XEmacs source directory:

$ cp -p lwlib/xlwmenu.c lwlib/xlwmenu.c.orig
  hack, hack, hack....
$ diff -u lwlib/xlwmenu.c.orig lwlib/xlwmenu.c

Also note that if you cut & paste from an xterm to an XEmacs mail buffer
you will probably lose due to tab expansion.  The best thing to do is
to use an XEmacs shell buffer to run the diff commands, or ...
M-x cd to the appropriate directory, and issue the command `C-u M-!' from
within XEmacs.

Patches should be as single-minded as possible.  Mammoth patches can
be very difficult to place into the right slot.  They are much easier
to deal with when broken down into functional or conceptual chunks.
The patches submitted by Kyle Jones and Hrvoje Niksic are stellar
examples of how to "Do The Right Thing".

Each patch should be accompanied by an update to the appropriate
ChangeLog file.  Guidelines for writing ChangeLog entries is governed
by the GNU coding standards.  Please see
<http://www.gnu.org/prep/standards_toc.html>   [Change Logs section]
for details.

Do not submit context diffs (either -c or -u) of ChangeLogs.  Because
of the "stack" nature of ChangeLogs (new entries are always pushed on
the top), context diffs will fail to apply more often than they
succeed.  Simply cutting and pasting the entry from an Emacs buffer to
the mail buffer (beware of tab expansion!) is probably easiest.  The
Patcher library also will set up your ChangeLogs for you, and copy
them to the mail.  Context-less unified diffs (-U 0) are also
acceptable.

*** Patch discussion etiquette
-------------------------------

If you intend a patch for _application_ to the sources as is, _always_
post it to xemacs-patches, even if there are minor points you would
like to have discussed by others.  Not doing so will resulting in
patches getting "lost".  If you expect that the patch will not be
acceptable, but are using it to stimulate discussion, then don't post
to xemacs-patches.  Intermediate cases are up to your judgment;
unless you're sure you'll follow up with a "real" patch, better to err
on the side of posting to xemacs-patches.

Discussion of the _content_ of the patch (ie responses to reviewer
comments beyond "that's right, ok, I'll do it your way") should _always_
be posted to xemacs-beta or to xemacs-design.  If you're not sure
which is more appropriate, send it to xemacs-beta.  That is the most
widely read channel.

If discussion results in a bright idea and you come up with a new
patch, normally you should post it to both mailing lists.  The people
discussing on XEmacs Beta will want to know the outcome of the thread,
and you need to submit to XEmacs Patches as the "list of record."

If the old patch has been applied to CVS, then just submit the new one
as usual.  If it has not been applied, then it is best to submit a new
patch against CVS.  If possible do this as a reply to the original
patch post, or something following it in the thread.  (The point is to
get the original patch post's Message-ID in your References header.)
In this case, also use the keyword SUPERSEDES in the Subject header to
indicate that the old patch is no longer valid, and that this one
replaces it.

These rules will result in a fair number of cross posts, but we don't
yet have a better way to handle that.

Note: Developers should never post to xemacs-patches unless there is a
patch in the post.  We plan to enforce this with an automatic filter.

The exceptions are administrative.  If you have commit authorization,
then post a short COMMIT notice to xemacs-patches when you commit to
CVS.  Members of the Review Board will also post short notices of
administrative action (APPROVE, VETO, QUERY, etc) to xemacs-patches.

** Large contributions
======================

Perhaps you have a whole new mode, or a major synchronization with
upstream for a neglected package, or a synchronization with GNU Emacs
you would like to contribute.  We welcome such contributions, but they
are likely to be relatively controversial, generate more comments and
requests for revision, and take longer to integrate.  Please be
patient with the process.

*** Updates to existing packages
--------------------------------

If a package has gotten a bit out of date, or even started to bitrot,
we welcome patches to synchronize it with upstream/GNU Emacs versions.
Most packages end up varying somewhat from their GNU origins.  See
"Syncing with GNU Emacs" for hints.  Note that if you do a reasonably
large amount of syncing with GNU Emacs, you should log this in the
file itself as well as in the ChangeLog.

If the package is important to you, please consider becoming the
maintainer.  (See "New packages", below.)

*** New packages
----------------

If you have a new mode or other large addition that does not require
changes to the core, please consider submitting it as a package, and
becoming the maintainer.  You get direct commit privileges to the
repository for your package, "approval" privileges for your own
patches as well as third party patches to your package, and some
degree of veto power over patches you don't like.  In return, you are
expected to maintain friendly liaison with the upstream developer (if
you aren't the upstream developer), keep watch on the XEmacs Patches
list for relevant patches, and be available by email to other
developers for discussion of changes that impact your package.  It's
also a pretty standard route to the "core" development group, where we
have plenty of extra work waiting for volunteers.

You don't have to become the maintainer, but it virtually ensures
rapid acceptance of the package.

For help in creating new packages, see the (rather sparse) discussions
in the XEmacs User's Guide and the Lisp Reference Manual.  The XEmacs
Package Release Engineer (Ville Skytt� <scop@xemacs.org> is currently
serving with Norbert Koch <viteno@xemacs.org> assisting; Steve
Youngs <youngs@xemacs.org> and Stephen Turnbull <stephen@xemacs.org>
also can help) are the most likely sources of advice.

*** Syncing with GNU Emacs
--------------------------

Syncing with GNU Emacs is an important activity.  Although each
version has its advantages and areas of concentration, it is very
desirable that common functionality share specifications and APIs.
When porting GNU code to XEmacs, the following points should be given
special attention:

  o Recent GNU Emacsen cannot be built without Mule, but XEmacs can.
    Make sure your changes do not assume the presence of Mule.

  o GNU Emacs nomenclature often differs from that of XEmacs.
    Sometimes syncing the names is desirable, other times not.

  o GNU Emacs functionality often differs from that of XEmacs.
    Syncing functionality is often controversial.

It is important that you let other developers know that
synchronization has taken place, to what degree, and when.  For this
purpose, we use comments of the form

/* Synched up with: FSF 21.3 by Stephen Turnbull */

in the source file itself, as the last element of the prefatory
material (copyright notice and commentary).  Obviously the comment
marker needs to be changed to leading semicolons for Lisp, but
otherwise the format is the same.

Of course you should note syncing as the purpose in the ChangeLog,
too.  But entries get buried deep in the ChangeLog file, and may even
get moved to a separate ChangeLog.OLD file for rarely synched files.

Rather than dates we use the version of GNU Emacs to sync to.  If the
synchronization is partial, add a new comment describing what has
actually been synched, leaving the description of the last full sync
in place.  At each full sync, remove all previous synchronization
comments.

This applies to Lisp that we have broken out into packages, but
remains in the GNU Emacs core, as well to core Lisp in XEmacs.