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+-*- outline -*-
+
+This file attempts to describe the rules to use when hacking Octave.
+Don't put this file into the distribution.
+
+* Working from the repository
+
+These notes intend to help people working on the checked-out sources.
+These requirements do not apply when building from a distribution
+tarball.
+
+** Requirements
+
+We've opted to keep only the highest-level sources in the repository.
+This eases our maintenance burden, (fewer merges etc.), but imposes
+more requirements on anyone wishing to build from the just-checked-out
+sources.  For example, you have to use the latest stable versions of
+the maintainer tools we depend upon, including:
+
+  - Autoconf <http://www.gnu.org/software/autoconf/>
+  - Automake <http://www.gnu.org/software/automake/>
+  - Bison <http://www.gnu.org/software/bison/>
+  - Flex <http://www.gnu.org/software/flex/>
+  - Git <http://git-scm.com/>
+  - Gnulib <http://www.gnu.org/software/gnulib/>
+  - GNU Make <http://www.gnu.org/software/make/>
+  - Gzip <http://www.gnu.org/software/gzip/>
+  - Libtool <http://www.gnu.org/software/libtool/>
+  - Mercurial <http://mercurial.selenic.com/>
+  - Perl <http://www.cpan.org/>
+  - Rsync <http://samba.anu.edu.au/rsync/>
+  - Tar <http://www.gnu.org/software/tar/>
+
+Only building the initial full source tree will be a bit painful.
+Later, after synchronizing from the repository a plain `make' should
+be sufficient.
+
+** First checkout
+
+Obviously, if you are reading these notes, you did manage to check out
+this package from the repository.  For the record, you will find all the
+relevant information on:
+
+  http://savannah.gnu.org/hg/?group=octave
+
+After checking out Octave, you will need to run the autogen.sh
+script:
+
+  $ ./autogen.sh
+
+This script will examine the source tree and generate some Makefile
+fragments and then runs the bootstrap script.  The bootstrap script comes
+from gnulib but is kept in the Octave source archive.  It should be
+updated from the gnulib source as necssary.  The bootstrap script takes
+care of checking out a copy of gnulib, running the autotools, and
+generating the configure script.  Once the autogen.sh and bootstrap
+scripts complete successfully, you may run
+
+  $ ./configure
+  $ make
+  $ make check
+
+At this point, there should be no difference between your local copy,
+and the master copy:
+
+  $ hg diff
+
+should output no difference.
+
+Additional information about coding style 
+
+This file will eventually be extended to explain more about updating
+Octave, preparing patches, and making releases.
+
+Enjoy!
+
+-----
+
+Copyright (C) 2009 John W. Eaton
+
+This file is part of Octave.
+
+Octave is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 3 of the License, or (at
+your option) any later version.
+
+Octave is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with Octave; see the file COPYING.  If not, see
+<http://www.gnu.org/licenses/>.
+
+
+This file was adapted for Octave from the HACKING file that is part of
+GNU Bison, which contained the following Copyright notice:
+
+  Copyright (C) 2002, 2003, 2004, 2005, 2007, 2008, 2009
+  Free Software Foundation, Inc.
+
+  This file is part of GNU Bison.
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.