pcom.p
  *     Authors:                                *
  *           Urs Ammann                        *
  *           Kesav Nori                        *
  *           Christian Jacobi                  *

pint.p
  (*K. Jensen, N. Wirth, Ch. Jacobi, ETH May 76*)


---------- Forwarded message ---------
From: Steven Pemberton <Steven.Pemberton@no.spam>
Date: Mon, Aug 23, 2010 at 9:46 AM
Subject: Re: Pascal: P4 copyright (I know, boring)
To: Rugxulo <rugxulo@no.spam>


As the opening of the P4 code states:

  (***********************************************
   *                                            *
   *     Portable Pascal compiler               *
   *     ************************               *
   *                                            *
   *            Pascal P4                       *
   *                                            *
   *     Authors:                               *
   *          Urs Ammann                        *
   *          Kesav Nori                        *
   *          Christian Jacobi                  *
   *     Address:                               *
   *      Institut Fuer Informatik              *
   *      Eidg. Technische Hochschule           *
   *      CH-8096 Zuerich                       *

So there are the authors (not me, I just wrote a book on it).

Niklaus Wirth specifically wrote to me to say that it is Public Domain,
which means that anyone can do anything they like with it, without asking
for permission. Since that was in the 1970's, I doubt I still have that
letter...

Wirth is now retired. I don't know about the other three.

Hope this helps.

Best wishes,

Steven


On Sun, 15 Aug 2010 04:43:20 +0200, Rugxulo <rugxulo@no.spam> wrote:

> Okay, I know you're probably busy with your small children or just
> busy in general. And I know this is tedious and boring, but I have to
> ask ....
>
> Recently, GPC has stagnated (even though it works pretty well) due to
> various reasons. So a rewrite is tentatively (!) being planned. Some
> ideas were outputting C++ source code or rewriting in Pascal (instead
> of C) in order to take advantage of more Pascal developers (instead of
> few C devs since Pascal <> C).
>
> Long story short, I think Scott Moore suggested using P5 (his ISO 7185
> complete improvement to the P4 subset) as a good starting point, esp.
> since GPC prefers standards over Borland ad hoc crud.
>
> But Frank (head of GPC) says informal declarations of P4 as "public
> domain" aren't good enough. He wants some kind of explicit agreement
> from the original authors (or you or equivalent) that proves that it
> is indeed free for reasonable or even commercial reuse (similar to GPL
> freedom since GPC currently uses that).
>
> Any ideas?? I'm not 100% sure who the original authors are anyways,
> and even if I take a guess (Amman, Nori, Jacobi, Wirth, Jensen), I
> don't know how to contact them reliably.     :-/

----------------------------------------------------------------------
p2c.h
/* Header file for code generated by "p2c", the Pascal-to-C translator */

/* "p2c"  Copyright (C) 1989, 1990, 1991 Free Software Foundation.
 * By Dave Gillespie, daveg@no.spam  Version 1.20
 * This file may be copied, modified, etc. in any way.  It is not restricted
 * by the licence agreement accompanying p2c itself.
 */

p2clib.c
/* Run-time library for use with "p2c", the Pascal to C translator */

/* "p2c"  Copyright (C) 1989, 1990, 1991 Free Software Foundation.
 * By Dave Gillespie, daveg@no.spam  Version 1.20
 * This file may be copied, modified, etc. in any way.  It is not restricted
 * by the licence agreement accompanying p2c itself.
 */

----------------------------------------------------------------------
README for P4 compiler/interpreter

Included are the sources to the P4 Pascal -> P-code compiler and to the
P-code interpreter. The original source-code was written in Pascal, which
was transformed to C-code, using p2c.
(Details of the conversion can be found in the headers of the C-files)

You can redistribute all the source code freely, the p2c library source
and the code generated by it are NOT subject to the GNU general public
license. The original Pascal source-code is public domain.

Enjoy

Send reactions to

I.J.A.vanGeel@no.spam

Date: august 22 1996

----------------------------------------------------------------------
LICENSE from Scott Moore (aka Scott Franco)

Pascal-P4 is the original sources of the Pascal-P compiler from ETH
Zurich, as created by Niklaus Wirth and his students. It was and is
public domain, as acknowledged by Professor Wirth, and I add my
modifications to it to the public domain as well.

Public domain is a widely misunderstood concept. There is no "license"
possible nor needed for public domain works. There are no restrictions
on it's use, nor do it's authors have any rights to it. It can be used
for any purpose, public or private, and distributed or modified for
any use whatever, paid or not.

The following are typical answers to questions about public domain
works in general, and this work in specific.

Q. The Berne convention states that copyright in Europe, where
   Pascal-P originated, is automatic. Doesn't that make Pascal-P a
   copyrighted work?

A. The laws in all copyright countries dictate what must be done to
   qualify as a copyrighted work. Since there is no specific legal
   agreement concerning public domain work, public domain is shaped by
   what constitutes enforceable copyright. The most common features of
   public domain are, but not limited to:

   1. The author has stated the work is public domain.

   2. The work has been distributed freely and with knowledge of the
      author(s).

In the case of Pascal-P, both are true.

Q. Doesn't public domain mean that I may no longer be able to gain
   access to the source?

A. If every copy of the work were to be erased or burned, but that is
   virtually impossible. Nobody can order you to release your copy since,
   by definition, there are no "rights" to a public domain work.

Q. Can't someone just copyright or patent the work later?

A. Showing that a work is in the public domain is part of denying
   copyright or patent to a work. By definition, a legitimate public
   domain work cannot later be copyrighted or patented.

Q. Can't someone improve the work, then gain rights to that derived
   work and thus restrict it's use?

A. Anyone can improve a public domain work, but they only have rights
   to their improvements, not to the original work. If their improvements
   are trivial, then it would be trivial for others to add that
   functionality. If it is not trivial, then you might want to pay for
   it.

----------------------------------------------------------------------
Any changes made by me are also released into the public domain.

-- Rugxulo (Anthony Williams)
