Screen version 4.00.03 (FAU) 23-Oct-06 GPL issues

Question

I am using Screen command with following version :-

Screen version 4.00.03 (FAU) 23-Oct-06

I want to know which GPL version(GPLv2 or GPLv3) associated with Screen command. Any help from where i could find out ?

Answer 1

I have that same version on my Fedora 14 machine. man screen contains a COPYLEFT section that states:

   Copyright (C) 1993-2003
        Juergen Weigert ([email protected])
        Michael Schroeder ([email protected])
   Copyright (C) 1987 Oliver Laumann
   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, 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 MER‐
   CHANTABILITY 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 (see the file COPYING); if not,  write  to  the  Free
   Software  Foundation,  Inc.,  59  Temple  Place - Suite 330, Boston, MA
   02111-1307, USA

so that says GPLv2, or later if you prefer.

You can also find the license in /usr/share/doc/screen-4.0.3/COPYING which confirms that is Version 2.

Answer 2

FAU Screen vs GNU screen

"Screen (FAU)" seems to be the Apple OS X / macOS version of screen.

Les Googles

Google doesn't seem to know where fau screen comes from either:

https://www.google.com/search?q=%22Screen+version+4.00.03+(FAU)+23-Oct-06%22

Les Filesystem

Neither locate screen-4.0.3 nor locate '/screen/' yield any interesting results.

strings /usr/bin/screen does reveal the same license shown above:

Copyright (c) 1993-2002 Juergen Weigert, Michael Schroeder
Copyright (c) 1987 Oliver Laumann
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, 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 (see the file COPYING); if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
Send bugreports, fixes, enhancements, t-shirts, money, beer & pizza to [email protected]

However, this version of screen doesn't seem to behave like "real" screen (it doesn't work with ssh, for example), so my guess is that it's a fork.

Apple Open Source

Apple publishes the sources to this (potential) fork:

https://opensource.apple.com/source/screen/screen-22/

And there is a changelog:

https://opensource.apple.com/source/screen/screen-22/screen/patchlevel.h.auto.html

However, if you peruse a bit through the various versions of OS X open source (https://opensource.apple.com/) you can find potentially different versions of FAU screen (such as https://opensource.apple.com/source/screen/screen-19/screen/) that have the exact same version output.