About
=====

GNU libextractor is a library used to extract meta data from files of
arbitrary type.  It is designed to use helper-libraries to perform the
actual extraction, and to be trivially extendable by linking against
external extractors for additional file types.  Common use-cases for
GNU libextractor include detail-views in file managers, detailed
search results in file-sharing networks and general information
gathering in forensics investigations and penetration testing.

GNU libextractor is a simple C library with a small API.  Bindings for
GNU libextractor exists for many languages in addition to the standard
C/C++ API (we know about bindings for Java, Perl, PHP, Mono, Python,
Ruby).

libextractor uses a plugin mechanism to enable developers to quickly
add extractors for additional formats.  Plugins are executed
out-of-process and can thus bugs in them (or the libraries that they
use) cannot crash the main application.  libextractor typically ships
with a few dozen plugins that can be used to obtain keywords from
common file types.

More detailed documentation is available in the GNU libextractor
manual.  libextractor is an official GNU package and available from
http://www.gnu.org/s/libextractor/.


Joining GNU
===========

This is a GNU program, developed by the GNU Project and part of the
GNU Operating System. If you are the author of an awesome program and
want to join us in writing Free Software, please consider making it an
official GNU program and become a GNU maintainer.  You can find
instructions on how to do so at http://www.gnu.org/help/evaluation.
We are looking forward to hacking with you!


extract
=======

extract is a simple command-line interface to GNU libextractor.


Dependencies
============

* GNU C/C++ compiler
* libltdl 2.2.x (from GNU libtool)
* GNU libtool 2.2 or higher
* GNU gettext

The following dependencies are all optional, but should be
available in order for maximum coverage:

* libarchive
* libbz2 (bzip2)
* libexiv2
* libflac
* libgif (giflib)
* libglib (glib)
* libgtk+
* libgsf
* libgstreamer
* libjpeg (v8 or later)
* libmagic (file)
* libmpeg2
* libmp4v2
* librpm
* libsmf
* libtidy
* libtiff
* libvorbis / libogg
* libz (zlib)

When building libextractor binaries, please make sure all of these
dependencies are available and configure detects a sufficiently recent
installation.  Otherwise the build system may automatically build only
a subset of GNU libextractor resulting in mediocre meta data
production.

Finally, 'zzuf' is a fuzzing tool that can optionally be detected by
the build system and be used for debugging / testing.  It is not required
at runtime or for normal builds.