You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 
Thomas Schmitt cc4d72bf8b Corrected comment 10 years ago
cdrskin Corrected comment 10 years ago
doc Lifted ban to derive GPLv3, extended copyright range to 2010 10 years ago
libburn Corrected comment 10 years ago
libcevap Fixed a bug about arrays 12 years ago
test Let libburner warn programmers if they forget to set 64 bit off_t 10 years ago
AUTHORS Cleaned up authors file, move Lorenzo to contributors 13 years ago
CONTRIBUTORS Cleaned up authors file, move Lorenzo to contributors 13 years ago
COPYING Initial import 14 years ago
COPYRIGHT Lifted ban to derive GPLv3, extended copyright range to 2010 10 years ago
ChangeLog Added dummy NEWS, Changelog, and Install - libburn tree 13 years ago
INSTALL Added dummy NEWS, Changelog, and Install - libburn tree 13 years ago
Makefile.am New system adapter for Solaris uscsi (tested on snv134, kernel 5.11) 10 years ago
NEWS Added dummy NEWS, Changelog, and Install - libburn tree 13 years ago
README New system adapter for Solaris uscsi (tested on snv134, kernel 5.11) 10 years ago
acinclude.m4 Forcing use of /usr/local on FreeBSD by LDFLAGS and CPPFLAGS 10 years ago
bootstrap Repaired broken macro settings during Linux build 13 years ago
configure.ac Made number transition to 0.8.1 10 years ago
libburn-1.pc.in Renamed libburn-5.pc to libburn-1.pc 12 years ago
version.h.in Initial import 14 years ago

README

------------------------------------------------------------------------------
libburnia-project.org
------------------------------------------------------------------------------
This all is under GPL.
(See GPL reference, our clarification and commitment at the end of this text)
------------------------------------------------------------------------------
libburn-project.org
By Mario Danic <mario.danic@gmail.com> and Thomas Schmitt <scdbackup@gmx.net>
Copyright (C) 2006-2010 Mario Danic, Thomas Schmitt
Still containing parts of Libburn. By Derek Foreman <derek@signalmarketing.com>
and Ben Jansens <xor@orodu.net>
Copyright (C) 2002-2006 Derek Foreman and Ben Jansens

http://files.libburnia-project.org/releases/libburn-0.8.0.pl00.tar.gz

------------------------------------------------------------------------------

Build and Installation

From tarball

Obtain libburn-0.8.0.pl00.tar.gz, take it to a directory of your choice and do:

tar xzf libburn-0.8.0.pl00.tar.gz
cd libburn-0.8.0
./configure --prefix=/usr
make

To make libburn accessible for running resp. application development,
and to install the cdrecord compatibility binary cdrskin, do
(as Superuser):

make install

This procedure installs libburn.so.4 and cdrskin depending on it.
For a standalone cdrskin binary, see cdrskin/README.

A behavioral conflict is known between any burn software and demons like hald
which probe CD drives. This can spoil burn runs for CD-R or CD-RW.
You may have to keep your hald away from the drive. See for example
http://www.freebsd.org/gnome/docs/halfaq.html


From SVN

Our build system is based on autotools. For preparing the build of a SVN
snapshot you will need autotools of at least version 1.7.
Do in a directory of your choice:

svn co http://svn.libburnia-project.org/libburn/trunk libburn-svn
cd libburn-svn
./bootstrap
./configure --prefix=/usr
make
make install

Warning: The trunk might contain experimental features which might not
persist until next release.


Special ./configure options

In some situations Linux may deliver a better write performance to drives if
the track input is read with O_DIRECT (see man 2 open). The API call
burn_os_open_track_src() and the input readers of cdrskin and libburn fifo
can be told to use this peculiar read mode by:
--enable-track-src-odirect

But often libburn call burn_write_opts_set_dvd_obs(opts, 64*1024) will yield
even better performance in such a situation. 64k can be made default at
configure time by:
--enable-dvd-obs-64k
This may be combined with above --enable-track-src-odirect .

Alternatively the transport of SCSI commands can be done via libcdio-0.83.
You may install it and re-run libburn's ./configure with option
--enable-libcdio

Make sure to re-compile all source files after running ./configure
make clean ; make
make install


------------------------------------------------------------------------------

An important part of the project, libisofs, is hosted in a bzr repository at
launchpad.net :
bzr branch lp:libisofs

Another part the project, libisoburn, is hosted in the libburnia SVN, too:
svn co http://svn.libburnia-project.org/libisoburn/trunk libisoburn

See README files there.

------------------------------------------------------------------------------


Overview of libburnia-project.org

libburnia-project.org is an open-source software project for reading, mastering
and writing optical discs.
For now this means CD media, all DVD media except DVD-R DL, all BD media.

The project comprises of several more or less interdependent parts which
together strive to be a usable foundation for application development.
These are libraries, language bindings, and middleware binaries which emulate
classical (and valuable) Linux tools.
Currently it is supported on GNU/Linux with kernels >= 2.4,
on FreeBSD with ATAPI/CAM enabled in the kernel (see man atapicam),
and on OpenSolaris (tested with kernel 5.11).
On other X/Open compliant systems there will only be pseudo drives, but no
direct MMC operation on real CD/DVD/BD drives.

For full ports to other systems we would need : login on a development machine
resp. a live OS on CD or DVD, advise from a system person about the equivalent
of Linux sg or FreeBSD CAM, volunteers for testing of realistic use cases.

We have a well tested code base for burning data and audio CDs, DVDs and BDs.
The burn API is quite comprehensively documented and can be used to build a
presentable application.
We have a functional application which emulates the core use cases of cdrecord
in order to prove that usability, and in order to allow you to explore
libburn's scope by help of existing cdrecord frontends.

ISO 9660 filesystems with Rock Ridge and Joliet extensions can be created
and manipulated quite freely. This capability together with our burn capability
makes possible a single binary application which covers all steps of image
composition, updating and writing. Quite unique in the Linux world.

The project components (list subject to growth, hopefully):

- libburn is the library by which preformatted data get onto optical media.
It uses either /dev/sgN (e.g. on kernel 2.4 with ide-scsi) or
/dev/srM or /dev/hdX (e.g. on kernel 2.6).
libburn is the foundation of our cdrecord emulation. Its code is
independent of cdrecord. Its DVD capabilities are learned from
studying the code of dvd+rw-tools and MMC-5 specs. No code but only
the pure SCSI knowledge has been taken from dvd+rw-tools, though.

- libisofs is the library to pack up hard disk files and directories into a
ISO 9660 disk image. This may then be brought to CD via libburn.
libisofs is to be the foundation of our upcoming mkisofs emulation.

- libisoburn is an add-on to libburn and libisofs which coordinates both and
also allows to grow ISO-9660 filesystem images on multi-session
media as well as on overwriteable media via the same API.
All media peculiarities are handled automatically.

- cdrskin is a limited cdrecord compatibility wrapper for libburn.
cdrecord is a powerful GPL'ed burn program included in Joerg
Schilling's cdrtools. cdrskin strives to be a second source for
the services traditionally provided by cdrecord. Additionally it
provides libburn's DVD capabilities, where only -sao is compatible
with cdrecord.
cdrskin does not contain any bytes copied from cdrecord's sources.
Many bytes have been copied from the message output of cdrecord
runs, though.
See cdrskin/README for more.

- xorriso is an application of all three libraries which creates, loads,
manipulates and writes ISO 9660 filesystem images with
Rock Ridge extensions. Manipulation is not only adding or
overwriting of files but also deleting, renaming, attribute
changing, incremental backups, activating boot images, and
extracting of files from ISO images to disk. An own ISO 9660
extension stores ACLs, xattr, and MD5 of file content.
See xorriso/README for more.

- "test" is a collection of application gestures and examples given by the
authors of the library features. The burn API example of libburn
is named test/libburner.c . The API for media information inquiry is
demonstrated in test/telltoc.c .
Explore these examples if you look for inspiration.

We strive to be a responsive upstream.

Our libraries are committed to maintain older feature sets in newer versions.
This applies to source code headers (API) as well as to linkable objects (ABI).
The only exception from this rule is about non-release versions x.y.*[13579]
which are allowed to introduce new features, change those new features in
any way and even may revoke such new features before the next release of
x.y.*[02468]. As soon as it is released, a feature is promised to persist.

SONAMES:
libburn.so.4 (since 0.3.4, March 2007),
libisofs.so.6 (since 0.6.2, February 2008),
libisoburn.so.1 (since 0.1.0, February 2008).

Applications must use 64 bit off_t. E.g. by defining
#define _LARGEFILE_SOURCE
#define _FILE_OFFSET_BITS 64
or take special precautions to interface with the libraries by 64 bit integers
where the .h files prescribe off_t. To reduce libburn's off_t size to 32 bit
will keep it from processing tracks of more than 2 GB size.


------------------------------------------------------------------------------
Project history as far as known to me:

- Founded in 2002 as it seems. See mailing list archives
http://lists.freedesktop.org/archives/libburn/
The site of this founder team is reachable and offers download of a
(somewhat outdated) tarball and from CVS :
http://icculus.org/burn/
Copyright holders and most probably founders:
Derek Foreman and Ben Jansens.

- I came to using libburn in 2005. Founded the cdrskin project and submitted
necessary patches which were accepted or implemented better. Except one
remaining patch which prevented cdrskin from using vanilla libburn from CVS.
The cdrskin project site is reachable and offers download of the heavily
patched (elsewise outdated) tarball under the name cdrskin-0.1.2 :
http://scdbackup.sourceforge.net/cdrskin_eng.html
It has meanwhile moved to use vanilla libburn.pykix.org , though.
Version 0.1.4 constitutes the first release of this kind.

- In July 2006 our team mate Mario Danic announced a revival of libburn
which by about nearly everybody else was perceived as unfriendly fork.
Derek Foreman four days later posted a message which expressed his
discontent.
The situation first caused me to publically regret it and then - after i
got the opportunity to move in with cdrskin - gave me true reason to
personally apologize to Derek Foreman, Ben Jansens and the contributors at
icculus.org/burn. Posted to both projects:
http://lists.freedesktop.org/archives/libburn/2006-August/000446.html
http://mailman-mail1.webfaction.com/pipermail/libburn-hackers/2006-August/000024.html

- Mid August 2006 project cdrskin established a branch office in
libburn.pykix.org so that all maintainers of our tools have one single place
to get the current (at least slightely) usable coordinated versions of
everything.
Project cdrskin will live forth independendly for a while but it is committed
to stay in sync with libburn.pykix.org (or some successor, if ever).
cdrskin is also committed to support icculus.org/burn if the pending fork
is made reality by content changes in that project. It will cease to maintain
a patched version of icculus.org/burn though. Precondition for a new
release of cdrskin on base of icculus.org/burn would be the pending
"whitelist patch" therefore.
I would rather prefer if both projects find consense and merge, or at least
cooperate. I have not given up hope totally, yet.
I, personally, will honor any approach.

- 2nd September 2006 the decision is made to strive for a consolidation of
copyright and a commitment to GPL in a reasonable and open minded way.
This is to avoid long term problems with code of unknown origin and
with finding consense among the not so clearly defined group of copyright
claimers and -holders.
libisofs is already claimed sole copyright Mario Danic.
cdrskin and libburner are already claimed sole copyright Thomas Schmitt.
Rewrites of other components will follow and concluded by claiming full
copyright within the group of libburn.pykix.org-copyright holders.

- 16th September 2006 feature freeze for release of libburn-0.2.2 .

- 20th September 2006 release of libburn-0.2.2 .

- 26th October 2006 feature freeze for cdrskin-0.2.4 based on libburn-0.2.3 .
This version of cdrskin is much more cdrecord compatible in repect
to drive addressing and audio features.

- 30th October 2006 release of cdrskin-0.2.4 .

- 13th November 2006 splitting releases of libburn+cdrskin from libisofs.

- 24th November 2006 release of libburn-0.2.6 and cdrskin-0.2.6 . cdrskin has
become suitable for unaware frontends as long as they perform only the core
of cdrecord use cases (including open-ended input streams, audio, and
multi-session).

- 28th November 2006 the umbrella project which encloses both, libisofs and
libburn, is now called libburnia. For the origin of this name, see
http://en.wikipedia.org/wiki/Liburnians .

- 16th January 2007 release of libburn-0.3.0 and cdrskin-0.3.0 . Now the scope
is widened to a first class of DVD media: overwriteable single layer types
DVD-RAM, DVD+RW, DVD-RW. This is not a cdrecord emulation but rather inspired
by dvd+rw-tools' "poor man" writing facility for this class of media.
Taking a bow towards Andy Polyakov.

- 11th February 2007 version 0.3.2 covers sequential DVD-RW and DVD-R with
multi-session and with DAO.

- 12th March 2007 version 0.3.4 supports DVD+R and thus covers all single layer
DVD media. Code for double layer DVD+/-R is implemented but awaits a tester
yet.

- 23th April 2007 version 0.3.6 follows the unanimous opinion of Linux kernel
people that one should not use /dev/sg on kernel 2.6.

- 31st July 2007 version 0.3.8 marks the first anniversary of libburn revival.
We look back on improved stability, a substantially extended list of media
and write modes, and better protection against typical user mishaps.

- 24th October 2007 version 0.4.0 is the foundation of new library libisoburn
and an upcomming integrated application for manipulating and writing
ISO 9660 + Rock Ridge images. cdrskin-0.4.0 got capabilities like growisofs
by these enhancements: growing of overwriteable media and disk files.
Taking again a bow towards Andy Polyakov.

- 26th Januar 2008 version 0.4.2 rectifies the version numbering so that we
reliably release libburn.so.4 as should have been done since libburn-0.3.2.
cdrskin now is by default linked dynamically and does a runtime check
to ensure not to be started with a libburn which is older than itself.

- 3rd Feb 2008 libisofs-0.2.x (.so.5) has been deprecated.

- 14th Feb 2008 libisofs-0.6.2 permanently replaces the old libisofs-0.2.x.
It is the first release of new libisofs.so.6 which will guarantee future
API/ABI compatibility for its whole feature set.

- 15th Feb 2008 libisoburn-0.1.0 (.so.1) coordinates libisofs and libburn for
the purpose of ISO image reading and writing. It emulates multi-session on
overwriteable media. Application xorriso makes use of all three libraries.

- 8th Apr 2008 libburn-0.4.4 has proven to be capable of burning to DVD+R/DL
and read performance on disk file pseudo-drives has been improved.

- 27th Apr 2008 libisofs-0.6.4 can now read data file content from images
and can map pieces of disk files onto image files. Image directory iteration
has been enhanced. Input data streams and extended information have been
exposed in the API to allow future development.

- 29th Apr 2008 libisoburn-0.1.4 was made more efficient with reading of
image tree nodes. It now depends on libisofs-0.6.4 and libburn-0.4.4.
xorriso makes use of new libisofs features by performing incremental
updates of directory trees and by cutting oversized data files into
pieces. A primitive single session emulation of cdrecord and mkisofs is
provided.

- 10th May 2008 libburn-0.4.6 supports formatting and writing of BD-RE,
full nominal speed for DVD-RAM and BD-RE. cdrskin has a unified blank
type with automatic media state recognition.

- 17th May 2008 an old bug with DVD-RAM and now with BD-RE is fixed by
libburn-0.4.8 to allow libisoburn emulation of multisession on those media.

- 19th May 2008 libisoburn-0.1.6 brings better table-of-content emulation
on overwriteble media and disk files.

- 1st Jun 2008 libisofs-0.6.6 fixes some problems around device files.

- 3rd Jun 2008 libisoburn-0.1.8 fixes a bug with overwriteable media.

- 23rd Jun 2008 libisoburn-0.2.0 introduces extraction of files from
ISO images.

- 16th Jul 2008 libburn-0.5.0 handles systems with no /dev/sr* but only
/dev/scd*.

- 19th Jul 2008 libisoburn/xorriso-0.2.2 can do multi-session in mkisofs
and cdrecord style. xorriso now can serve underneath growisofs.

- 20th Aug 2008 libburn-0.5.2 revokes the necessity that a drive must be
enumerable in order to be adressable. Enumeration is enhanced by examining
/proc/sys/dev/cdrom/info.

- 24th Aug 2008 libisoburn/xorriso-0.2.4 introduces a media readability check
with data retrieval option.

- 18th Sep 2008 libisofs-0.6.8 supports ISO 9660 Level 3 which allows very
large data files in the image.

- 20th Sep 2008 libisoburn/xorriso-0.2.6 takes into respect the new Level 3
capabilities of libisofs.

- 6th Oct 2008 libburn-0.5.4 adjusts the changes of 0.5.2 to the needs of
Linux kernel 2.4 and introduces human readable SCSI error messages.

- 6th Oct 2008 libisofs-0.6.10 fixes two bugs which prevented adding and
manipulation of ISOLINUX boot images.

- 15th Oct 2008 libisoburn/xorriso-0.2.8 can activate and maintain an
ISOLINUX boot image by an EL Torito boot record.

- 12th Nov 2008 libburn-0.5.6 fixes usage of freed memory by the fifo thread
of an aborted burn run.

- 26th Nov 2008 libisofs-0.6.12 can produce a ISOLINUX isohybrid MBR on the fly
and allows to produce ISO images which resemble old mkisofs images.

- 2nd Dec 2008 libisoburn-0.3.0. xorriso now is ready for exotic character
sets, for legacy FreeBSD systems which expect an outdated Rock Ridge
signature, and for producing ISO images with MBR which boot from hard disk
or USB stick. Three minor bugs were fixed.

- 7th Dec 2008 libburn-0.5.8 prevents a SIGSEGV with wierd CD table-of-content
and improves BD-RE formatting.

- 9th Dec 2008 Our project received a donation from Thomas Weber.

- 2nd Jan 2009 libburn-0.6.0 allows to format BD-R and to write to either
formatted or unformatted BD-R.

- 6th Jan 2009 libisoburn-0.3.2. xorriso can produce and execute commands for
mounting older sessions from all kinds of media. Pseudo-drives outside the
/dev/ tree can be addressed without prefix "stdio:".

- 20th Feb 2009 libburn-0.6.2 source release now compiles out of the box
on FreeBSD.

- 28 Feb 2009 libisofs-0.6.14 can record ACLs and Extended Attributes xattr
in its ISO images.

- 01 Mar 2009 libisoburn-0.3.4. xorriso makes use of the ACL and xattr
capabilities provided by libisofs for xorriso backup features.

- 11 Mar 2009 libisofs-0.6.16 of libisofs fixes two bugs which on Solaris
prevented to navigate the ISO images by ".." and to recognize the Rock Ridge
extensions of ISO images. The ban to build libisofs on operating systems
other than Linux and FreeBSD has been lifted.

- 13 Mar 2009 libburn-0.6.4 got a dummy adapter for SCSI/MMC command transport.
It will show no drives and thus libburn will only be able to perform
operations on "stdio:" pseudo drives. Nevertheless this allowed to lift the
ban to build libburn on operating systems other than Linux and FreeBSD.

- 16 Mar 2009 libisoburn-0.3.6: xorriso uses RRIP version 1.10 as default
in order to be mountable where mkisofs images are mountable.

- 17 Apr 2009 libisofs-0.6.18 introduces content filtering of data files.
Built-in filters allow compression to formats gzip and zisofs. External
filter processes allow arbitrary data conversions like encryption.

- 19 Apr 2009 libisoburn-0.3.8 makes use of the new libisofs capability to
perform content filtering of data files.

- 08 May 2009 libburn-0.6.6 fixes a bug with aborting on broken output pipe
and a bug with device scan on FreeBSD.

- 31 May 2009 libisofs-0.6.20 can record hard link relations in ISO images
and offers support with restoring them to disk. Current Linux kernels will
mount images with such hard links but will attribute a unique inode number
to each file.

- 28 Jun 2009 libisoburn-0.4.0: xorriso can record and restore hard link
relations of files. Performance of data reading has been improved. Option
-find now supports logical operators with its tests.

- 14 Jul 2009 libburn-0.6.8 fixes bugs and shortcommings with old MMC-1 drives
and with large SCSI bus numbers as handed out by Linux for USB drives.

- 20 Jul 2009 libisoburn-0.4.0.pl01 fixes a regression in xorriso which caused
data loss in older sessions if xorriso was used underneath growisofs.
Affected are releases since libisoburn-0.3.2 in january 2009.

- 25 Aug 2009 libisofs-0.6.22 can record MD5 checksums for the whole session
and for each single data file. Checksum tags allow to verify superblock and
directory tree before importing them.

- 27 Aug 2009 libburn-0.7.0 allows to calm down a drive and to inquire its
supported profiles. It works around some pitfalls with U3 enhanced memory
sticks which emulate a CD-ROM.

- 27 Aug 2009 libisoburn-0.4.0.pl00 can record MD5 checksums by which one may
verify the session or single data files in the image. When comparing image
files with files in the local filesystem, the MD5 sums avoid the need for
reading file content from the image.

- 22 Sep 2009 libisoburn-0.4.0.pl01 fixes a bug in xorriso option -cut_out.

- 08 Oct 2009 libisofs-0.6.24 fixes a bug which could cause the loss of blanks
in file names when a new session got added to an ISO image. With names
shorter than 251 characters this happened only to trailing blanks.

- 08 Oct 2009 libisoburn-0.4.0.pl02 fixes bugs with xorriso option -for_backup,
with xorrisofs -help, and with xorrecord -help.

- 12 Oct 2009 libburn-0.7.2 fixes a bug with CD TAO multi-track dummy sessions.
It can retrieve media product info and can process track input which was
prepared for CD-ROM XA Mode 2 Form 1. cdrskin now performs option -minfo.

- 28 Oct 2009 libisoburn-0.4.4 fixes a bug with cdrecord emulation and
introduces new information options about media type and ISO image id strings.
On Linux it helps with mounting two sessions of the same media
simultaneously.

- 12 Nov 2009 libburn-0.7.2.pl01 works around problems with Pioneer DVR-216D.
DVD-R runs made the drive stuck. Ejecting the tray did not work properly.

- 06 Dec 2009 libburn-0.7.4 works around problems with newer DVD burners,
provides throughput enhancements with hampered busses on Linux, and new
API calls to log SCSI commands and to control the libburn fifo.

- 09 Dec 2009 libisoburn-0.4.6 allows performance tuning of output to DVD
drives or disk files.

- 26 Dec 2009 libburn-0.7.4.pl01 fixes the release tarball which was lacking
the files of the generic system adapter for X/Open.

- 29 Dec 2009 Our project received a donation for purchasing a fine small
computer which shall serve as OS farm for development and support.

- 20 Jan 2010 Version 0.6.26 of libisofs fixes minor bugs and shall enhance
portability.

- 22 Jan 2010 libburn-0.7.6 has an improved system adapter for FreeBSD,
fixes bugs about the generic X/Open system adapter, and allows to use
libcdio >= 0.83 as SCSI transport facility.

- 10 Feb 2010 libisofs-0.6.28 fixes a regression about bootable images which
was introduced by version 0.6.22 in August 2009.

- 23 Feb 2010 libisoburn-0.5.0 marks the transition of the xorriso standalone
version to an official GNU project. The name changed to "GNU xorriso" and its
license is now GPLv3+.
The licenses of libburnia libraries and applications are not affected by
this change.

- 10 Mar 2010 libburn-0.7.8 fixes bugs and improves the built-in abort handler
on FreeBSD.

- 30 Mar 2010 Release 0.5.2 of libisoburn provides xorriso documentation in
GNU Texinfo format with embedded extra data to derive a full man page.

- 09 Apr 2010 libburn-0.8.0 now works with ahci driver on FreeBSD 8-STABLE.


------------------------------------------------------------------------------

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License version 2 or later
as published by the Free Software Foundation.

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, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

------------------------------------------------------------------------------
Clarification in my name and in the name of Mario Danic, upcoming copyright
holders on toplevel of libburnia. To be fully in effect after the remaining
other copyrighted code has been replaced by ours and by copyright-free
contributions of our friends:
------------------------------------------------------------------------------

We, the copyright holders, agree on the interpretation that dynamical linking
of our libraries constitutes "use of" and not "derivation from" our work in
the sense of GPL, provided those libraries are compiled from our unaltered
code or from altered code published under GPL.

So we will not raise legal protest if you link our libraries dynamically with
applications which are not under GPL, or if you distribute our libraries
and application tools in binary form, as long as you fulfill the usual
condition of GPL to offer a copy of their source code -altered or unaltered-
under GPL.

We ask you politely to use our work in open source spirit
and with the due reference to the entire open source community.

If there should really arise the case where above clarification
does not suffice to fulfill a clear and neat request in open source
spirit that would otherwise be declined for mere formal reasons,
only in that case we will duely consider to issue a special license
covering only that special case.
It is the open source idea of responsible freedom which will be
decisive and you will have to prove that you exhausted all own
means to qualify for GPL.

For now we are firmly committed to maintain one single license: GPL.

signed: Mario Danic, Thomas Schmitt
Agreement joined later by: Vreixo Formoso