libisofs/README

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                                    libisofs
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Released under GPL (see COPYING file for details).

Copyright (C) 2008 - 2010 Vreixo Formoso, Mario Danic, Thomas Schmitt

libisofs is part of the libburnia project (libburnia-project.org)
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libisofs is a library to create an ISO-9660 filesystem, supports extensions
like RockRidge or Joliet, and introduces an own extension AAIP.
It is a full featured ISO-9660 editor which composes and changes the directory
tree of an ISO image. This tree and its newly imported data file contents get
then written as independent single-session image or as add-on session for the
image from where the tree was originally loaded.

Features:
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- Image creation
	- Creates ISO-9660 images from local files.
	- Support for RockRidge and Joliet extensions.
	- Support for ISO-9660:1999 (version 2).
	- Support for El-Torito bootable images.
	- Support for multi-extent data files up to 400 GB (level 3).
	- Full-featured edition of the image files, including: addition of new
	  files, removing of existent files, moving files, renaming files,
	  change file attributes (permissions, timestamps...)
	- Optional recording per file of non-ISO 9660 features:
	  ACL, xattr, content MD5, hard link relations.
	  They do not hamper image readability by operating systems but can be
	  retrieved only via libisofs.
	- Optional zisofs compression, gzip compression, external filter
	  processes.
	- Several options to relax ISO-9660 constraints.
	- Special options for images intended for distribution (suitable
	  default modes for files, hiding of real timestamps...).
- Image reading
	- Image tree and data heap can be verified by stream reading and
	  eventually recorded MD5 tags.
	- Directory tree and file attributes of ISO 9660 session get loaded
	  into memory for editing or for extraction into local filesystem.
	- File content can be read by applications.
	- Automatic zisofs decompression.
	- Optional application of gzip decompression or external filter
	  processes.
	- Eventually recorded MD5 of data file can be obtained, MD5 of data
	  stream can be computed and compared.
	- Helper functions for restoring ACL and/or xattr to the local
	  filesystem.
- Multisession
	- Support for growing an existing image on multi-session media.
	- Support for "emulated multisession" on overwriteable media such as
	  DVD+RW, USB sticks, regular files.
	- Support for blindly prepared add-on sessions (mkisofs style -M -C)
	  suitable for pipes which lead to an external burn program.
- Image modification
	- Creates a completely new image from files out of another image and
	  eventual editing operations. Suitable for any target medium.
- Others
	- Handling of different input and output charset.
	- Good integration with libburn for image burning.
	- Reliable, good handling of different kind of errors.

Requirements:
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- libburn 0.4.2 headers must be installed at compile time. It is not required
  at runtime.
  
Know bugs:
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Multisession and image growing can lead to undesired results in several cases:

a) Images with unsupported features, such as:
	- UDF.
	- HSF/HFS+ or other Mac extensions.
	- El-Torito with multiple entries.
	- ECMA-119 with extended attributes.
	- Non El-Torito boot info.
	- ...
   In all these cases, the resulting new image (or new session) could lack some
   features of the original image.
   In some cases libisofs will issue warning messages, or even refuse to grow
   or modify the image. Others remain undetected. Images created with libisofs
   do not have this problems.

b) Bootable El-Torito images may have several problems, that result in a new
   image that is not bootable, or that boots from an outdated session. In many
   cases it is recommended to add boot info again in the new session.
   
    - isolinux images won't be bootable after a modify. This is because 
      isolinux images need to have hardcoded the root dir lba. libisofs cannot 
      know whether an image is an isolinux image or not, so the user is 
      responsible to tell libisofs that it must patch the image, with the
      el_torito_patch_isolinux_image() function. This problem could also exists
      on other boot images.
	- Most boot images are highly dependent of the image contents, so if the 
	  user moves or removes some files on image it is possible they won't boot 
	  anymore.
	- There is no safer way to modify hidden boot images, as the size of the 
	  boot image can't be figured out.

c) Generated images could have different ECMA-119 low level names, due to 
   different way to mangle names, to new files added that force old files to 
   be renamed, to different relaxed contraints... This only affect the 
   ISO-9660 info, not the RR names, so it shouldn't be a problem in most
   cases. If your app. relies on low level ISO-9660 names, you will need to 
   ensure all node names are valid ISO names (maybe together with some
   relaxed contraints), otherwise libisofs might arbitrarily change the names.


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                        Download, Build and Installation

libisofs code is mantained in a Bazaar repository at Launchpad 
(https://launchpad.net/libisofs/). You can download it with:

$ bzr branch lp:libisofs

Our build system is based on autotools. For preparing the build you will need 
autotools of at least version 1.7. If you have download the code from the
repository, first of all you need to execute

   ./autogen.sh
   
on toplevel dir to execute autotools.

Alternatively you may unpack a release tarball for which you do not need
autotools installed.

To build libisofs it should be sufficient to go into its toplevel directory 
and execute

   ./configure --prefix=/usr
   make

To make the libraries accessible for running resp. developing applications 
   make install

See INSTALL file for further details.


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    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

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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.

Note:
In the particular case of libisofs there is no foreign copyright involved.
As of 2010 foreign copyright is only in component libburn.
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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