# Background information for new users of Ghostscript

## Table of contents

- An overview of Ghostscript
  - How is Ghostscript licensed? Where can I find it?
    - GNU Ghostscript
  - Libraries obtained from other parties
  - What if I want support?
  - What about commercial use?
  - What platforms does Ghostscript run on?
    - Ports done by users
- Related work
  - Drivers
  - Previewers
    - Previewers for X Windows
    - Previewers for DOS and MS Windows
    - A previewer for GNU/Linux
  - Related programs
- If you need help
  - Reporting problems
- Contacting Ghostscript headquarters
- How you can help improve Ghostscript
- Acknowledgements

For other information, see the Ghostscript overview.

## An overview of Ghostscript

Ghostscript is the name of a set of software that provides:

- An interpreter for the PostScript TM language and the Adobe Portable Document Format (PDF -- sometimes confused with Acrobat, Adobe's PDF browser and editor product);
- Input modules (utilities) for reading a variety of raster formats, including CMYK, GIF, JFIF (JPEG), MIFF, PBM/PGM/PPM, and PCX;
- Output modules (drivers) for a wide variety of window systems (including X Windows and Microsoft Windows), raster file formats, and printers, as well as a PDF output module that implements functions similar to Adobe's AcrobatTM DistillerTM product; and
- The Ghostscript library, a set of procedures to implement the graphics and filtering capabilities that are primitive operations in the PostScript language and in PDF.

In simple terms, this means that Ghostscript can read a PostScript or PDF file and display the results on the screen or convert them into a form you can print on a non-PostScript printer. Especially together with several popular previewers, with Ghostscript you can view or print an entire document or even isolated pages, even if your computer doesn't have Display PostScript and your printer doesn't handle PostScript itself.

### How is Ghostscript licensed? Where can I find it?

Ghostscript is a copyrighted work (artofcode LLC owns the copyright); it is not shareware or in the public domain. Different versions of it are distributed with three different licenses:

#### GNU Ghostscript

GNU Ghostscript is distributed under the terms of the GNU General Public License, which allows free use, and free copying and redistribution under certain conditions (including, in some cases, commercial distribution). You can always get the current version of GNU Ghostscript by Internet FTP from any of the many GNU distribution sites. The GNU home ftp site is

> ftp://ftp.gnu.org/pub/gnu/

For a more complete list of sites, including sites outside the U.S. and other ways of obtaining GNU software, contact the Free Software Foundation <gnu@gnu.org>.

Versions of Ghostscript are also available from sites in the Comprehensive TeX Archive Network (CTAN), in a tree based at /tex-archive/support/ghostscript/, which you can find at these principal CTAN distribution sites ("participating hosts") as of mid-1998:

> ftp://ctan.tug.org/tex-archive/support/ghostscript/ |  | Massachusetts, U.S.A.
> ftp://ftp.dante.de/tex-archive/support/ghostscript/ |  | Deutschland
> ftp://ftp.tex.ac.uk/tex-archive/support/ghostscript/ |  | United Kingdom

CTAN has more than fifty mirror sites around the world. For information about CTAN sites, including how to use them over the World Wide Web, visit ctan.org or get the file `CTAN.sites` from any CTAN server, for instance

> ftp://ctan.tug.org/tex-archive/CTAN.sites

### Libraries obtained from other parties

The Ghostscript source code distribution, and the Ghostscript executable code, include libraries obtained from other parties. All the source files mentioned in this section are in the Ghostscript and third-party library source kits. The documentation of how to build Ghostscript tells where to get these libraries and how to unpack them.

> The Independent JPEG Group (IJG) library
>   The executable versions of Ghostscript are based in part on the work of the Independent JPEG Group. For more information, see `jpeg.mak` in the main Ghostscript source directory and `README` in the libjpeg source directory.
> The Portable Network Graphics (PNG) library created by Dave Martindale, Guy Eric Schalnat, Paul Schmidt, and Tim Wegner, of Group 42, Inc.
>   For more information, see `libpng.mak` in the main Ghostscript source directory, and `README` and `png.h` in the libpng source directory.
> The zlib library created by Jean-loup Gailly and Mark Adler
>   For more information, see `zlib.mak` in the main Ghostscript source directory, and `README` in the zlib source code.

These libraries do not fall under the GPL but come with their own licenses, which also allow free use and redistribution under appropriate circumstances and which appear in the files mentioned just above. These libraries are entirely original works of their respective authors, and are provided as is with no warranty and no support.

### What if I want support?

Neither artofcode LLC nor any organization known to us currently offers Ghostscript support for end-users -- that is, for people or companies who just want to use Ghostscript and not redistribute it as part of a product.

Nothing in the GNU license prevents anyone from providing support for Ghostscript, either free or commercial. We would be happy to include in the Ghostscript documentation the contact information for anyone who wants to offer such support.

### What platforms does Ghostscript run on?

Ghostscript is written entirely in C, with special care taken to make it portable to a wide variety of systems. It is actively maintained on many unix-like operating systems, Microsoft Windows, Apple's MacOS and OpenVMS and can easily be ported to others. Please see Making Ghostscript for details on the build process and hints for various platforms.

## Related work

### Drivers

A number of people have created Ghostscript drivers that they prefer to distribute directly, rather than including them in the Ghostscript distributions. Please refer to www.linuxprinting.org or your favorite search engine for relevant examples.

### Previewers

The Ghostscript user interface is very primitive, so several people have contributed screen previewers with better user interfaces.

#### Previewers for X Windows

`GSPreview`
  For information on GSPreview, contact Richard Hesketh <rlh@ukc.ac.uk>.

#### Previewers for DOS and MS Windows

`psv`
  `PSV`, another keyboard-based PostScript viewing package for DOS, appears to be redistributable with no restrictions. It was once available from

  > ftp://puccini.ujf-grenoble.fr/pub/contrib-ps/DOS-PSV/

#### A previewer for GNU/Linux

`BMV`
  Jan Kybic has created a Ghostscript-based bitmap previewing program for GNU/Linux called `BMV`, which doesn't use X Windows but is based on `svgalib`. He says there is a port of `BMV` for SCO Unix by William Bader. `BMV` is available from

  > ftp://sunsite.unc.edu/pub/Linux/apps/graphics/viewers/svga/bmv-1.2.tgz

### Related programs

`genscript`
  `genscript` is a free replacement for the `enscript` program. `genscript` converts plain text files to PostScript and sends the generated PostScript output to the specified printer or to a file. `genscript` can be easily extended to handle different output media, and it has many options which can be used to customize printouts, including 2-up printing, pagination, complex headers, and many more. You can find the current version at

  > http://www.iki.fi/~mtr/genscript/ (home page)
  > ftp://ftp.gnu.org/pub/gnu/enscript/enscript-*.tar.gz

`pstotext`
  A good free utility `pstotext` uses Ghostscript to extract plain text from PostScript files. It is much better than the `ps2ascii` utility distributed with Ghostscript. You can read the `pstotext` documentation at

  > http://www.research.digital.com/SRC/virtualpaper/manpages/pstotext.1.html

  and download the `pstotext` kit from

  > http://www.research.digital.com/SRC/virtualpaper/pstotext.html

  `pstotext` is unsupported, but the authors, Paul McJones <paul.mcjones@acm.org> and Andrew Birrell <birrell@pa.dec.com>, are happy to have your questions and comments either by e-mail or here

  For more information about the authors' Virtual Paper project, which attempts to make on-line reading of lengthy material (like research reports, manuals, or entire books) comfortable, read:

  > http://www.research.digital.com/SRC/virtualpaper

`PreScript`
  This is another good free utility that uses Ghostscript to extract text from PostScript or PDF files. It can also generate very simple HTML, keeping some of the formatting. It is unsupported, but is the product of an active research project. Its home page is:

  > http://www.nzdl.org/html/prescript.html

## If you need help

The list of Frequently Asked Questions (FAQ) isn't updated very often, so it may be somewhat out of date. It's available from

> http://www.cs.wisc.edu/~ghost/doc/faq.htm
> ftp://mirror.cs.wisc.edu/pub/mirrors/ghost/faq.htm

or by AFS from

> /afs/cs.wisc.edu/p/mirror/pub/mirrors/ghost/faq.htm

CompuServe announced in December 1995 that the Graphics Support Forum offers Message Section and Library 21, "Ghostscript", for technical assistance with Ghostscript. Ghostscript is available for downloading in Library 21, "Ghostscript." To access the Graphics Support Forum, `GO GRAPHSUP`. This service has no connection with the main Ghostscript developers.

If you have problems with Ghostscript and you have access to the Internet, we suggest to post your question to one of these Usenet newsgroups:

`gnu.ghostscript.bug`
  if your question is about GNU Ghostscript. If you have access to Internet mail, but not Usenet news, write to `bug-ghostscript@gnu.org`, which is equivalent to posting to that newsgroup.
`comp.lang.postscript`
  if you have a general question about Ghostscript. Note however that this newsgroup was not intended for Ghostscript discussion per se.

There are hundreds of Ghostscript user sites all over the world, and another user will often be able to help you. If you have trouble with a specific device driver, look at `devs.mak` and `contrib.mak` in the Ghostscript source directory to see in which file the driver is defined. If it's defined in `contrib.mak`, the list of contributed drivers, please contact the author directly: the maintainers of Ghostscript can't help you with user-maintained drivers.

### Reporting problems

Please read Bug-info.htm for information about reporting problems.

## Contacting Ghostscript headquarters

As of mid-September 2000, artofcode LLC is responsible for the future development of Ghostscript. Please do not contact us if all you want is help with Ghostscript! Ghostscript is free, but our time is not. If you call for help, we will tell you politely that we cannot answer your question. Ghostscript's documentation, while not of commercial end-user quality, has been adequate for thousands of users (for many of whom English is a foreign language), so the answer to your question is very likely in it somewhere.

Here is our contact information:

### Aladdin Enterprises

Aladdin Enterprises, the original authors of Ghostscript, is no longer responsible for Ghostscript, but may be available for small contract projects. Here is their contact information:

If you want help with Ghostscript, or want to report a problem, please do not contact us. We will not be able to help you.

## How you can help improve Ghostscript

The most valuable thing you can do to help improve Ghostscript is to help test it. We make three different grades of release available, each of which needs a different kind of testing.

- Stable releases are made available about every 9 months, after a beta test period. Reporting problems as described above often results in a fix being posted on our Web site.

- Beta releases are posted starting about 6 weeks before a planned public release. These are candidates for public release, and need intensive testing.

- Development releases are posted every few weeks. These are not supposed to be good enough for general use, but testing them is still very helpful, since it gets problems corrected before the intensive beta test period.

You can always find the current public release and the current beta or tester release on our Web site. If you would like to be notified when new beta or tester releases are posted, please contact us.

There are also some useful projects that we don't have enough resources to work on, and with which we would appreciate help. See this list for details.

## Acknowledgements

Ghostscript was originally created, and through the year 2000 was primarily developed and maintained, by L. Peter Deutsch, President of Aladdin Enterprises (not to be confused with Peter J. Deutsch, founder of Bunyip Information Systems Inc.).

Special thanks are due to Russell Lang, for the `GSview for Windows` and `PM GSview` programs, and for contributing most of the code for the Microsoft Windows and OS/2 environments; to Tim Theisen, for the `Ghostview` program for X Windows and for major contributions to, and assistance with support of, the code for the X Windows environment; to Martin Fong and Mark Lentczner, for the first Macintosh ports; to Pete Kaiser <kaiser@acm.org>, for redoing all of the documentation in HTML; and to the Independent JPEG Group, to Group 42, Inc., and to Jean-loup Gailly and Mark Adler, for creating the freely available libraries that Ghostscript uses.

Special thanks are due to URW++ Design and Development Incorporated, of Hamburg, Germany (http://www.urwpp.de/) for making a commercial-quality set of the 35 standard PostScript Type 1 fonts available for free distribution under the GNU and Aladdin licenses, and for updating them to include Adobe's expanded PostScript 3 character set.

Special thanks are due to Richard Stallman and the Free Software Foundation for originating the GNU General Public License, for originally motivating Aladdin's interest in creating free software, and for being the primary distributor of GNU Ghostscript on the Internet.

See also the list of the many other people who have contributed significantly to improving Ghostscript.

Copyright © 1996-2002 artofcode LLC. All rights reserved.

This software is provided AS-IS with no warranty, either express or implied. This software is distributed under license and may not be copied, modified or distributed except as expressly authorized under the terms of the license contained in the file LICENSE in this distribution.

Ghostscript version 7.06, 1 April 2003