From: Dave Mason <dmason AT plg DOT uwaterloo DOT ca>
To: dj AT ctron DOT com
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Re: License??????????????
Date: Thu, 30 Jun 1994 22:32:26 -0400

> Date: Sat, 25 Jun 1994 18:57:08 -0400
> From: dj AT ctron DOT com (DJ Delorie)
> 
> Now that you mentioned it, I checked the flex.skeleton file and it
> doesn't include a copyright.  I guess that means it's not gpl, and so
> flex-generated source would be OK to distribute binary-only.

Actually more than that, the README says:
-----
Note that flex is distributed under a copyright very similar to that of
BSD Unix, and not under the GNU General Public License (GPL), except for
the "configure" script, which is covered by the GPL.
-----

And COPYING says:
-----
Flex carries the copyright used for BSD software, slightly modified
because it originated at the Lawrence Berkeley (not Livermore!) Laboratory,
which operates under a contract with the Department of Energy:

	Copyright (c) 1990 The Regents of the University of California.
	All rights reserved.

	This code is derived from software contributed to Berkeley by
	Vern Paxson.

	The United States Government has rights in this work pursuant
	to contract no. DE-AC03-76SF00098 between the United States
	Department of Energy and the University of California.
...

This basically says "do whatever you please with this software except
remove this notice or take advantage of the University's (or the flex
authors') name".

Note that the "flex.skl" scanner skeleton carries no copyright notice.
You are free to do whatever you please with scanners generated using flex;
for them, you are not even bound by the above copyright.
-----
This is why I always use byacc and flex.

../Dave