This is Info file kpathsea.info, produced by Makeinfo-1.64 from the
input file kpathsea.texi.

START-INFO-DIR-ENTRY
* Kpathsea: (kpathsea).		File lookup along search paths.
END-INFO-DIR-ENTRY

   This file documents the Kpathsea library for path searching.

   Copyright (C) 1993, 94, 95 Karl Berry.

   Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.

   Permission is granted to copy and distribute modified versions of
this manual under the conditions for verbatim copying, provided also
that the sections entitled "Freedom" and "GNU General Public License"
are included exactly as in the original, and provided that the entire
resulting derived work is distributed under the terms of a permission
notice identical to this one.

   Permission is granted to copy and distribute translations of this
manual into another language, under the above conditions for modified
versions, except that the sections entitled "Freedom" and "GNU General
Public License" may be included in a translation approved by the Free
Software Foundation instead of in the original English.


File: kpathsea.info,  Node: Basic glyph lookup,  Next: Fontmap,  Up: Glyph lookup

Basic glyph lookup
------------------

   When Kpathsea looks for a bitmap font NAME at resolution DPI in a
format FORMAT, it first checks each directory in the search path for a
file `NAME.DPIFORMAT'; for example, `cmr10.300pk'.  Kpathsea looks for
a PK file first, then a GF file.

   If that fails, Kpathsea looks for `dpiDPI/NAME.FORMAT'; for example,
`dpi300/cmr10.pk'. This is how fonts are typically stored on
filesystems (like DOS's) that permit only three-character extensions.

   If that fails, Kpathsea looks for a font with a close-enough DPI.
"Close enough" is defined (by the macro `KPSE_BITMAP_TOLERANCE' in
`kpathsea/tex-glyph.h') to be `DPI / 500 + 1', which is slightly more
than the 0.2% allowed by the DVI standard.


File: kpathsea.info,  Node: Fontmap,  Next: MakeTeX... scripts,  Prev: Basic glyph lookup,  Up: Glyph lookup

Fontmap
-------

   If a bitmap font is not found with the original name (see the
previous section), Kpathsea looks through any "fontmap" files for an
"alias" for the original font name.  These files are named
`texfonts.map' and are searched for along the usual glyph path.

   This feature is intended to help in two respects:

  1. An alias name is limited in length only by available memory, not
     by your filesystem.  Therefore, if you want to ask for
     `Adobe-Lucida-Bold-Sans=Typewriter' instead of `plcbst', you can.

  2. A few fonts have historically had multiple names: specifically,
     LaTeX's "circle font" has variously been known as `circle10',
     `lcircle10', and `lcirc10'.  Aliases can make all the names
     equivalent, so that it no longer matters what the name of the
     installed file is; TeX documents will find their favorite name.


   The format of fontmap files is straightforward: the first word on
each line is the true filename; the second word is the alias; subsequent
words are ignored.  A "word" is a sequence of non-whitespace
characters.  Blank lines are ignored; comments start with `%' and
continue to end-of-line.

   If an alias has an extension, it matches only those files with that
extension; otherwise, it matches anything with the same root,
regardless of extension.  For example, an alias `foo.tfm' matches only
when exactly `foo.tfm' is being searched for; but an alias `foo'
matches `foo.vf', `foo.300pk', etc.

   As an example, here are the fontmap entries that make the circle
fonts equivalent. These are in the distributed `texfonts.map' in the
Web2C distribution.

     circle10	lcircle10
     circle10	lcirc10
     lcircle10	circle10
     lcircle10	lcirc10
     lcirc10		circle10
     lcirc10		lcircle10


File: kpathsea.info,  Node: MakeTeX... scripts,  Next: Fallback font,  Prev: Fontmap,  Up: Glyph lookup

`MakeTeX'... scripts
--------------------

   If Kpathsea cannot find a bitmap font, by either its original name
or a fontmap alias, it can be configured to invoke an external program
to create it.  The same mechanism can be used for other nonexistent
files.

   The script is passed the name of the file to create and possibly
other arguments, as explained below.  It must echo the full pathname of
the file it created (and nothing else) to standard output; it can write
diagnostics to standard error.

* Menu:

* MakeTeX... script names::
* MakeTeX... script arguments::


File: kpathsea.info,  Node: MakeTeX... script names,  Next: MakeTeX... script arguments,  Up: MakeTeX... scripts

`MakeTeX'... script names
.........................

   The following table shows the default name of the script for each
possible file types.  (The source is the variable `kpse_make_specs' in
`kpathsea/tex-make.c'.)

`MakeTeXPK'
     Glyph fonts.

`MakeTeXTeX'
     TeX input files.

`MakeTeXMF'
     Metafont input files.

`MakeTeXTFM'
     TFM files.

These names are overridden by an environment variable specific to the
program--for example, `DVIPSMAKEPK' for Dvipsk.

   If a `MakeTeX...' script fails, the invocation is appended to a file
`missfont.log' in the current directory. If the current directory is
not writable and the environment variable `TEXMFOUTPUT' is set, its
value is used. Otherwise, nothing is written.


File: kpathsea.info,  Node: MakeTeX... script arguments,  Prev: MakeTeX... script names,  Up: MakeTeX... scripts

`MakeTeX'... script arguments
.............................

   The first argument to a `MakeTeX'... script is always the name of
the file to be created.

   For `MakeTeXPK', three or four additional arguments are also passed,
via corresponding environment variables:

  1. The dpi to make the font at (`KPATHSEA_DPI').

  2. The "base dpi" the program is operating at (`MAKETEX_BASE_DPI'),
     i.e., the assumed resolution of the output device.

  3. A "magstep" string suitable for the Metafont `mag' variable
     (`MAKETEX_MAG').

  4. Optionally, a Metafont mode name to assign to the Metafont `mode'
     variable (`MAKETEX_MODE').  Otherwise, (the default) `MakeTeXPK'
     guesses the mode from the resolution.  *Note TeX directory
     structure: TeX directory structure.

  5. Optionally, a directory name. If the directory is absolute, it is
     used as-is. Otherwise, it is appended to the root destination
     directory set in the script (from environment variables `DESTDIR'
     or `MTP_DESTDIR' or a compile-time default). If this argument is
     not supplied, the mode name is appended to the root destination
     directory.


Kpathsea sets `KPATHSEA_DPI' appropriately for each attempt at building
a font.  It's up to the program using Kpathsea to set the others.
(*Note Calling sequence::.)

   You can change the specification for the arguments passed to the
external script by setting the environment variable named as the script
name, but all capitals--`MAKETEXPK', for example.  If you've changed
the script name by setting (say) `DVIPSMAKEPK' to `foo', then the spec
is taken from the environment variable `FOO'.

   The spec can contain any variable references, to the above variables
or any others you might have set.  As an example, the default spec for
`MakeTeXPK' is:

     $KPATHSEA_DPI $MAKETEX_BASE_DPI $MAKETEX_MAG $MAKETEX_MODE

The convention of passing the name of the file to be created as the
first argument cannot be changed.


File: kpathsea.info,  Node: Fallback font,  Prev: MakeTeX... scripts,  Up: Glyph lookup

Fallback font
-------------

   If a bitmap font cannot be found or created at the requested size,
Kpathsea looks for the font at a set of "fallback resolutions".  You
specify these resolutions as a colon-separated list (like search paths).
Kpathsea looks first for a program-specific environment variable (e.g.,
`DVIPSSIZES' for Dvipsk), then the environment variable `TEXSIZES',
then a default specified at compilation time (the Make variable
`default_texsizes').  You can set this list to be empty if you prefer
to find fonts at their stated size or not at all.

   Finally, if the font cannot be found even at the fallback
resolutions, Kpathsea looks for a fallback font, typically `cmr10'.
Programs must enable this feature by assigning to the global variable
`kpse_fallback_font' or calling `kpse_init_prog' (*note Calling
sequence::.); the default is no such fallback font.


File: kpathsea.info,  Node: TeX directory structure,  Next: Programming,  Prev: TeX searching,  Up: Top

TeX directory structure
***********************

   (This section obviously not really written yet; sorry.  See
`kpathsea/HIER'.)

   By default, the bitmap font paths end with `$MAKETEX_MODE', thus
including the device name (i.e., the Metafont mode) in the path.  This
is to make it possible to distinguish two different devices with the
same resolution--write/white and write/black 300dpi printers, for
example.

   However, since most sites don't have this complication, Kpathsea
(specifically, `kpse_init_prog' in `kpathsea/proginit.c') has a special
case: if the mode has not been explicitly set by the user (or in a
configuration file), it sets `MAKETEX_MODE' to `/'.  This makes the
default PK path, for example, expand into `.../pk//', so fonts will be
found even if there is no subdirectory for the mode.  (If your site has
only one printer, for example.)

   To make the paths independent of the mode, simply edit
`texmf.cnf.in' before installation, or the installed `texmf.cnf'.
*Note Default paths::.

   *Note `MakeTeX'... script arguments: MakeTeX... script arguments,
for how this interacts with `MakeTeXPK'.


File: kpathsea.info,  Node: Programming,  Next: Copying,  Prev: TeX directory structure,  Up: Top

Programming
***********

   This chapter is for programmers who wish to use Kpathsea. *Note
Introduction::, for the conditions under which you may do so. (If you
do this, I'd appreciate a note, just to satisfy my curiousity.)

* Menu:

* Overview: Programming overview:	 Introduction.
* Calling sequence::			 Specifics of what to call.
* Config: Programming with config files:	Getting info from texmf.cnf.


File: kpathsea.info,  Node: Programming overview,  Next: Calling sequence,  Up: Programming

Programming overview
====================

   Aside from this manual, your best source of information is the
source to the programs I've modified to use Kpathsea (also listed in the
introduction). Of those, Dviljk is probably the simplest, and hence a
good place to start. Xdvik adds VF support and the complication of X
resources. Dvipsk adds the complication of its own config files.

   Beyond these of examples of use, the `.h' files in the Kpathsea
source describe the interfaces and functionality (and of course the
`.c' files define the actual routines, which are the ultimate
documentation).  `pathsearch.h' declares the basic searching routine.
`tex-file.h' and `tex-glyph.h' define the interfaces for looking up
particular kinds of files.

   The library provides no way for an external program to register new
file types: `tex-file.[ch]' must be modified to do this. For example,
Kpathsea has support for looking up Dvips config files, even though
obviously no program other than Dvips will ever want to do so. I felt
this was acceptable, since along with new file types should also come
new defaults in `texmf.cnf' (and its descendant `paths.h'), since it's
best for users if they can modify one configuration file for all kinds
of paths.

   Kpathsea does not open any files or parse any formats itself. Its
purpose is only to return filenames. The GNU font utilities source does
contain libraries to read TFM, GF, and PK files.


File: kpathsea.info,  Node: Calling sequence,  Next: Programming with config files,  Prev: Programming overview,  Up: Programming

Calling sequence
================

   The typical way to use Kpathsea in your program goes something like
this:

  1. Call `kpse_set_progname' with `argv[0]'; This is the only
     initialization that is mandatory to take full advantage of
     Kpathsea--specifically, for the `.PROGRAM' feature of config files
     (*note Config files::.).

     `kpse_set_progname' sets the global variables
     `program_invocation_name' and `program_invocation_short_name'.  It
     also initializes debugging flags based on the environment variable
     `KPATHSEA_DEBUG', if that is set.  set.

     The GNU C library provides these two global variables itself; in
     this case, the call to `kpse_set_program' does nothing. But you
     (as a software author) most likely do not want to force people
     installing your program to have glibc.

  2. Set debugging options. *Note Debugging::. If your program doesn't
     have a debugging flag already, you can define one and set
     `kpathsea_debug' to the number that the user supplies (see
     Dviljk), or you can just omit this altogether (people can always
     set `KPATHSEA_DEBUG').  If you do have runtime debugging already,
     you need to merge Kpathsea's options with yours (see Dvipsk and
     Xdvik).

  3. If your program has its own configuration files that can define
     search paths, you should assign those paths to the `client_path'
     member in the appropriate element of the `kpse_format_info' array.
     (This array is indexed by file type; see `tex-file.h'.)  See
     `resident.c' in Dvipsk for an example.

  4. Call `kpse_init_prog' (see `proginit.c'). It's useful for the DVI
     drivers, at least, but for other programs it may be simpler to
     extract the parts of it that actually apply.  This does not
     initialize any paths, it just looks for (and sets) certain
     environment variables and other random information.  (A search
     path is always initialized at the first call to find a file of
     that type; this eliminates much useless work, e.g., initializing
     the BibTeX search paths in a DVI driver.)

  5. The routine to actually find a file of type FORMAT is
     `kpse_find_FORMAT', defined in `tex-file.h'. These are macros that
     expand to a call to `kpse_find_file'.  You can call, say,
     `kpse_find_tfm' after doing only the first of the initialization
     steps above--Kpathsea will read the generic config file
     `texmf.cmf', look for environment variables, and do the expansions
     at the first lookup.

  6. To find PK and/or GF bitmap fonts, the routines are `kpse_find_pk',
     `kpse_find_gf' and `kpse_find_glyph', defined in `tex-glyph.h'.
     These return a structure in addition to the resultant filename,
     because fonts can be found in so many ways. See the documentation
     in the source.


   Kpathsea also provides many utility routines. Some are generic: hash
tables, memory allocation, string concatenation and copying, string
lists, reading input lines of unlimited length, etc. Others are
filename-related: default path, tilde, and variable expansion, `stat'
calls, etc. (Perhaps someday I'll move the former to a separate
library.)

   The `c-*.h' header files can also help your program adapt to many
different systems.  You will almost certainly want to use Autoconf for
configuring your software if you use Kpathsea; I strongly recommend
using Autoconf regardless.  You can get it by ftp from
`prep.ai.mit.edu' in `pub/gnu/autoconf-*.tar.gz', or from any of its
mirrors.


File: kpathsea.info,  Node: Programming with config files,  Prev: Calling sequence,  Up: Programming

Programming with config files
=============================

   You can use the same `texmf.cnf' configuration file as Kpathsea for
your program. This will help installers do all configuration in one
place.

   To retrieve a value VAR, the best way is to call `kpse_var_expand'
on the string `$VAR'. This will look first for an environment variable
VAR, then a config file value. The result will be the value found, or
the empty string. This function is declared in `kpathsea/variable.h'.

   If for some reason you want to retrieve a value *only* from a config
file, not automatically looking for a corresponding environment
variable, call `kpse_cnf_get' (declared in `kpathsea/cnf.h') with the
string VAR.

   No initialization calls are needed.


File: kpathsea.info,  Node: Copying,  Next: Freedom,  Prev: Programming,  Up: Top

GNU GENERAL PUBLIC LICENSE
**************************

                         Version 2, June 1991

     Copyright (C) 1989, 1991 Free Software Foundation, Inc.
     675 Mass Ave, Cambridge, MA 02139, USA
     
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Preamble
========

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     PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY
     SERVICING, REPAIR OR CORRECTION.

 13. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
     WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY
     MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE
     LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL,
     INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR
     INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
     DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU
     OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY
     OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN
     ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

                      END OF TERMS AND CONDITIONS

Appendix: How to Apply These Terms to Your New Programs
=======================================================

   If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these
terms.

   To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
convey the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.

     ONE LINE TO GIVE THE PROGRAM'S NAME AND A BRIEF IDEA OF WHAT IT DOES.
     Copyright (C) 19YY  NAME OF AUTHOR
     
     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 2 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, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

   Also add information on how to contact you by electronic and paper
mail.

   If the program is interactive, make it output a short notice like
this when it starts in an interactive mode:

     Gnomovision version 69, Copyright (C) 19YY NAME OF AUTHOR
     Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
     This is free software, and you are welcome to redistribute it
     under certain conditions; type `show c' for details.

   The hypothetical commands `show w' and `show c' should show the
appropriate parts of the General Public License.  Of course, the
commands you use may be called something other than `show w' and `show
c'; they could even be mouse-clicks or menu items--whatever suits your
program.

   You should also get your employer (if you work as a programmer) or
your school, if any, to sign a "copyright disclaimer" for the program,
if necessary.  Here is a sample; alter the names:

     Yoyodyne, Inc., hereby disclaims all copyright interest in the program
     `Gnomovision' (which makes passes at compilers) written by James Hacker.
     
     SIGNATURE OF TY COON, 1 April 1989
     Ty Coon, President of Vice

   This General Public License does not permit incorporating your
program into proprietary programs.  If your program is a subroutine
library, you may consider it more useful to permit linking proprietary
applications with the library.  If this is what you want to do, use the
GNU Library General Public License instead of this License.


File: kpathsea.info,  Node: Freedom,  Next: Index,  Prev: Copying,  Up: Top

Regain your programming freedom
*******************************

   Until a few years ago, programmers in the United States could write
any program they wished.  This freedom has now been taken away by two
developments: software patents, which grant the patent holder an
absolute monopoly on some programming technique, and user interface
copyright, which forbid compatible implementations of an existing user
interface.

   In Europe, especially through the GATT treaty, things are rapidly
approaching the same pass.

* Menu:

* Software patents::            Algorithm monopolies.
* User interface copyright::    Forbidding upward-compatibility.
* What to do?::                 What to do?


File: kpathsea.info,  Node: Software patents,  Next: User interface copyright,  Up: Freedom

Software patents
================

   The U.S. Patent and Trademark Office has granted numerous software
patents on software techniques.  Patents are an absolute
monopoly--independent reinvention is precluded.  This monopoly lasts
for seventeen years, i.e., forever (with respect to computer science).

   One patent relevant to TeX is patent 4,956,809, issued to the Mark
Williams company on September 11, 1990, applied for in 1982, which
covers (among other things)
     representing in a standardized order consisting of a standard
     binary structure file stored on auxiliary memory or transported on
     a communications means, said standardized order being different
     from a different order used on at least one of the different
     computers;

     Converting in each of the different computers binary data read
     from an auxiliary data storage or communications means from the
     standardized order to the natural order of the respective host
     computer after said binary data are read from said auxiliary data
     storage or communications means and before said binary data are
     used by the respective host computer; and

     Converting in each of the different computers binary data written
     into auxiliary data storage or communications means from the
     natural order of the respective host computer to the standardized
     order prior to said writing.

... in other words, storing data on disk in a machine-independent
order, as the DVI, TFM, GF, and PK file formats specify.  Even though
TeX is "prior art" in this respect, the patent was granted (the patent
examiners not being computer scientists, even less computer
typographers).  Since there is a strong presumption in the courts of a
patent's validity once it has been granted, there is a good chance that
users or implementors of TeX could be successfully sued on the issue.

   As another example, the X window system, which was intended to be
able to be used freely by everyone, is now being threatened by two
patents: 4,197,590 on the use of exclusive-or to redraw cursors, held
by Cadtrak, a litigation company (this has been upheld twice in court);
and 4,555,775, held by AT&T, on the use of backing store to redraw
windows quickly.

   Here is one excerpt from a recent mailing by the League for
Programming Freedom (*note What to do?::.) which I feel sums up the
situation rather well.  It comes from an article in `Think' magazine,
issue #5, 1990.  The comments after the quote were written by Richard
Stallman.

         "You get value from patents in two ways," says Roger Smith, IBM
        Assistant General Counsel, intellectual property law.
     "Through fees,     and through licensing negotiations that give
     IBM access to other     patents.

     "The IBM patent portfolio gains us the freedom to do what we need
     to     do through cross-licensing--it gives us access to the
     inventions of     others that are the key to rapid innovation.
     Access is far more     valuable to IBM than the fees it receives
     from its 9,000 active     patents.  There's no direct calculation
     of this value, but it's many     times larger than the fee income,
     perhaps an order of magnitude     larger."

   This information should dispel the belief that the patent system will
"protect" a small software developer from competition from IBM.  IBM
can always find patents in its collection which the small developer is
infringing, and thus obtain a cross-license.

   However, the patent system does cause trouble for the smaller
companies which, like IBM, need access to patented techniques in order
to do useful work in software.  Unlike IBM, the smaller companies do
not have 9,000 patents and cannot usually get a cross-license.  No
matter how hard they try, they cannot have enough patents to do this.

   Only the elimination of patents from the software field can enable
most software developers to continue with their work.

   The value IBM gets from cross-licensing is a measure of the amount of
harm that the patent system would do to IBM if IBM could not avoid it.
IBM's estimate is that the trouble could easily be ten times the good
one can expect from one's own patents--even for a company with 9,000 of
them.


File: kpathsea.info,  Node: User interface copyright,  Next: What to do?,  Prev: Software patents,  Up: Freedom

User interface copyright
========================

   (This section is copied from the GCC manual, by Richard Stallman.)

     This section is a political message from the League for Programming
     Freedom to the users of the GNU font utilities.  It is included
     here as an expression of support for the League on my part.

   Apple, Lotus and Xerox are trying to create a new form of legal
monopoly: a copyright on a class of user interfaces.  These monopolies
would cause serious problems for users and developers of computer
software and systems.

   Until a few years ago, the law seemed clear: no one could restrict
others from using a user interface; programmers were free to implement
any interface they chose.  Imitating interfaces, sometimes with changes,
was standard practice in the computer field.  The interfaces we know
evolved gradually in this way; for example, the Macintosh user interface
drew ideas from the Xerox interface, which in turn drew on work done at
Stanford and SRI.  1-2-3 imitated VisiCalc, and dBase imitated a
database program from JPL.

   Most computer companies, and nearly all computer users, were happy
with this state of affairs.  The companies that are suing say it does
not offer "enough incentive" to develop their products, but they must
have considered it "enough" when they made their decision to do so.  It
seems they are not satisfied with the opportunity to continue to compete
in the marketplace--not even with a head start.

   If Xerox, Lotus, and Apple are permitted to make law through the
courts, the precedent will hobble the software industry:

   * Gratuitous incompatibilities will burden users.  Imagine if each
     car manufacturer had to arrange the pedals in a different order.

   * Software will become and remain more expensive.  Users will be
     "locked in" to proprietary interfaces, for which there is no real
     competition.

   * Large companies have an unfair advantage wherever lawsuits become
     commonplace.  Since they can easily afford to sue, they can
     intimidate small companies with threats even when they don't
     really have a case.

   * User interface improvements will come slower, since incremental
     evolution through creative imitation will no longer be permitted.

   * Even Apple, etc., will find it harder to make improvements if they
     can no longer adapt the good ideas that others introduce, for fear
     of weakening their own legal positions.  Some users suggest that
     this stagnation may already have started.

   * If you use GNU software, you might find it of some concern that
     user interface copyright will make it hard for the Free Software
     Foundation to develop programs compatible with the interfaces that
     you already know.


File: kpathsea.info,  Node: What to do?,  Prev: User interface copyright,  Up: Freedom

What to do?
===========

   (This section is copied from the GCC manual, by Richard Stallman.)

   To protect our freedom from lawsuits like these, a group of
programmers and users have formed a new grass-roots political
organization, the League for Programming Freedom.

   The purpose of the League is to oppose new monopolistic practices
such as user-interface copyright and software patents; it calls for a
return to the legal policies of the recent past, in which these
practices were not allowed.  The League is not concerned with free
software as an issue, and not affiliated with the Free Software
Foundation.

   The League's membership rolls include John McCarthy, inventor of
Lisp, Marvin Minsky, founder of the Artificial Intelligence lab, Guy L.
Steele, Jr., author of well-known books on Lisp and C, as well as
Richard Stallman, the developer of GNU CC.  Please join and add your
name to the list.  Membership dues in the League are $42 per year for
programmers, managers and professionals; $10.50 for students; $21 for
others.

   The League needs both activist members and members who only pay their
dues.

   To join, or for more information, phone (617) 492-0023 or write to:

     League for Programming Freedom
     1 Kendall Square #143
     P.O. Box 9171
     Cambridge, MA 02139

   You can also send electronic mail to `league@prep.ai.mit.edu'.

   Here are some suggestions from the League for things you can do to
protect your freedom to write programs:

   * Don't buy from Xerox, Lotus or Apple.  Buy from their competitors
     or from the defendants they are suing.

   * Don't develop software to work with the systems made by these
     companies.

   * Port your existing software to competing systems, so that you
     encourage users to switch.

   * Write letters to company presidents to let them know their conduct
     is unacceptable.

   * Tell your friends and colleagues about this issue and how it
     threatens to ruin the computer industry.

   * Above all, don't work for the look-and-feel plaintiffs, and don't
     accept contracts from them.

   * Write to Congress to explain the importance of this issue.

          House Subcommittee on Intellectual Property
          2137 Rayburn Bldg
          Washington, DC 20515
          
          Senate Subcommittee on Patents, Trademarks and Copyrights
          United States Senate
          Washington, DC 20510

     (These committees have received lots of mail already; let's give
     them even more.)

   Express your opinion!  You can make a difference.

