223 lines
7.9 KiB
Plaintext
223 lines
7.9 KiB
Plaintext
This is the file README and belongs to version 0.9.4a of May 8, 1994
|
|
of the portable Forth-environment.
|
|
--------------------------------------------------------------------
|
|
|
|
What is it?
|
|
===========
|
|
|
|
This package contains all neccessary ANSI-C source files to build a
|
|
running Forth-environment on most UNIX machines, on DOS and on OS/2.
|
|
|
|
The Forth-system is closely modeled along the new American National
|
|
Standard for the programming language Forth. I implemented every word
|
|
of every word set mentioned in the dpANS-6 document of june 1993.
|
|
Additionally it is compatible to Forth-83.
|
|
|
|
This set of source files is distributed under the GNU general public
|
|
license for libraries. See the file COPYING.LIB for conditions.
|
|
|
|
I chose that one to point out that I don't consider programs you write
|
|
on top of it a 'derived work' of the portable Forth environment. To
|
|
violate these conditions you have to do two things together:
|
|
|
|
- you use a modified pfe to run your program
|
|
- you keep these modification secret
|
|
|
|
Should be easy to avoid.
|
|
|
|
|
|
Why did I do it?
|
|
================
|
|
|
|
For fun. As an excercise in unix programming. And there was no such
|
|
thing. See below, design objectives.
|
|
|
|
|
|
Design objectives
|
|
=================
|
|
|
|
With two elaborate standards at hand, one for C, one for Forth, it
|
|
should be possible to build one language in terms of the other and
|
|
thus provide both where at least one is available.
|
|
|
|
While I leave the writing of an ANSI-C compiler in Forth to those who
|
|
really believe in Forth's superiority and universality, I concentrated
|
|
on the manageable part: Providing a Forth-system in ANSI-C that is
|
|
|
|
- CORRECT this means not just "no bugs" -- it means all
|
|
the interaction of all parts works as specified
|
|
by the standard AND by traditions.
|
|
|
|
- COMPLETE with powerful computers on the desk and power-
|
|
ful programming environments there is no need
|
|
to and no use in strategies like "here kernel,
|
|
there xyz word set" that might be appropriate
|
|
on a microcontroller.
|
|
|
|
- PORTABLE I hate to rewrite code because of environmental
|
|
dependencies. Most of the system should be a mere
|
|
interface between two well defined languages.
|
|
There are of course such dependencies. I tried
|
|
to resort to a common subset of all UNIX bahavior
|
|
known to me. Fortunately this in fact allowed
|
|
porting to DOS and OS/2 thanks to the great
|
|
emx-package.
|
|
|
|
- USABLE A sole kernel helps noone. It should be a
|
|
development environment. You should be able
|
|
to manage multiple-source-file-projects from
|
|
within.
|
|
|
|
- SIMPLE or transparent. At least to my taste.
|
|
|
|
Maybe you miss the design objective SPEED. It was not my goal to
|
|
provide the fastest C-based Forth-environment. This would have led to
|
|
conflicts with much more important goals. We all have fast computers,
|
|
haven't we?
|
|
|
|
After all pfe isn't slow. With a little tuning using GNU-C's global
|
|
register variable feature it is pretty fast. But obviously it cannot
|
|
compete with assembler implementations.
|
|
|
|
|
|
Status
|
|
======
|
|
|
|
Did I achieve the above objectives?
|
|
Some of them. I'll continue working on it.
|
|
|
|
The system is in use for fifteen month now. Several quite obvious and
|
|
several quite subtle bugs have been fixed. While there surely are some
|
|
more, they are not as obvious since the system passes several test
|
|
programs, some of them rather sophisticated.
|
|
|
|
Once you get the system running, you'll have
|
|
|
|
- All ANSI Forth word sets with the exception of the assembler
|
|
hooks `CODE', `END-CODE' etc. Nothing else is missing.
|
|
|
|
- Several more words provided for compatibility and convenience.
|
|
|
|
- An interface to a text editor to edit plain text sources
|
|
and the ability to include them.
|
|
|
|
- A word star lookalike block file editor to write
|
|
source in the old style block format.
|
|
|
|
- A simple source level debugger -- maybe I should better
|
|
say "single stepper".
|
|
|
|
Thus you'll be able to edit, compile an run programs in a moderately
|
|
comfortable way. For the final design of the development environment
|
|
your suggestions still are welcome!
|
|
|
|
If you try this system, please keep in mind that it is still under
|
|
development. Sometimes new --even stupid-- bugs are introduced while
|
|
enhancing functionality or while fixing old ones. I appreciate every
|
|
hint to a bug and I fixed every bug I've been told about in the last
|
|
months. So please don't hesitate to tell me about whatever seems
|
|
wrong. Please check for the latest version via anonymous ftp from
|
|
|
|
roxi.rz.fht-mannheim.de:/pub/languages/forth/pfe-?.?.?.tar.gz
|
|
|
|
(accessible from germany only) or
|
|
|
|
sunsite.unc.edu:/pub/languages/forth/pfe-?.?.?.tar.gz
|
|
|
|
Please send suggestions and bug reports via e-mail to
|
|
|
|
duz@roxi.rz.fht-mannheim.de
|
|
|
|
|
|
Usage
|
|
=====
|
|
|
|
For installation refer to the files `install' and `tuning'.
|
|
|
|
Once you have it running and see the "ok" prompt after typing return
|
|
you can interactively type in forth words. If you mistype, you can
|
|
edit the command line and recall old command lines with the arrow
|
|
keys. (If you can't then your termcap doesn't work all right and you
|
|
can resort to wordstar-like control keys.)
|
|
|
|
To write some more statements try "EDIT-TEXT filename". This will
|
|
invoke your favorite text-file editor on the given file. If it
|
|
doesn't, first check the environment variable EDITOR, then check the
|
|
file "const.h" for the #defined symbol "EDITOR".
|
|
|
|
Having written some code you can load it by "INCLUDE filename".
|
|
|
|
If you prefer the old style block files, give a file to use as
|
|
block-file with the -b commandline option. Alternatively you can say
|
|
`USING filename' or if the file doesn't exist yet: `USING-NEW
|
|
filename'. Then you can edit a block by `n EDIT-BLOCK'.
|
|
|
|
If your termcap-mechanism works well, the arrow keys and some other
|
|
function keys should be active. Quit the editor with ^U and load
|
|
blocks with "n LOAD". If it doesn't work well you might not even get a
|
|
picture.
|
|
|
|
For more commandline options try the option -h.
|
|
|
|
The interrupt key is remapped to ^U and leads back to the FORTH input
|
|
loop. Use it to break out of infinite loops.
|
|
To terminate the system, type BYE at the command-prompt or press the
|
|
keyboard quit key of your system (usually ^\).
|
|
|
|
|
|
Documentation
|
|
=============
|
|
|
|
I started writing a documentation in texinfo format. This will allow
|
|
you to view it online or print it in good quality. There's also an
|
|
outdated and hopefully soon superseded man-page that explains some of
|
|
the command line options. All documentation is highly unfinished.
|
|
|
|
For more information please try to get the dpANS-document, which is
|
|
an EXCELLENT REFERENCE to this system! You can (could?) ftp it at
|
|
ftp.uu.net in the directory /vendor/minerva/x3j14.
|
|
|
|
|
|
Contributions
|
|
=============
|
|
|
|
are welcome! After the kernel is finished now it makes much sense to
|
|
share the burden of creating and improving a well rounded programming
|
|
environment for all tasks a Forth programmer wants to do. PFE is YOUR
|
|
tool. Get involved in it's design!
|
|
|
|
There is a mailing list on pfe which you should subscribe to if you
|
|
want to be up to date with the development of the system. Send e-mail
|
|
to duz@roxi.rz.fht-mannheim.de if you want to subscribe to that
|
|
mailing list.
|
|
|
|
|
|
Acknowledgements
|
|
================
|
|
|
|
I want to express my gratitude to the people who put their efforts in
|
|
the precise descriptions I found in these documents:
|
|
|
|
- draft proposed American National Standard -- Programming Languages
|
|
-- Forth (X3J14 dpANS-6, June 30, 1993)
|
|
|
|
- FORTH-83 Standard (August 1983)
|
|
|
|
- fig-FORTH Installation Manual -- Glossary, Model, Editor
|
|
(Version 1.3, November 1980)
|
|
|
|
Thanks for providing superb development tools:
|
|
|
|
- Richard Stallman and the FSF, Linus Thorvalds and all who
|
|
contribute to Linux and Eberhard Mattes.
|
|
|
|
Several nice people gave me valuable hints to bugs and possible
|
|
improvements, were patient enough to try the very first releases, made
|
|
ports to machines I never saw myself and kept me from frustration. If
|
|
pfe is stable now it is thanks to it's users. Most notably:
|
|
|
|
Lennert Benschop, Sean Conner, Holger Dietze, Kevin Haddock,
|
|
Rob Hooft, Giorgio Richelli, Marko Teiste, Guenther Thomsen.
|
|
|
|
Thank You.
|