I also was wondering about the pedigree of extra.zip.
The zip include a text file which identifies the packager as Julian Smart and the source as UnxUtils.
I have previously searched for the same utilities to enable the scintilla make files to work under cmd.exe and found them at
http://unxutils.sourceforge.net/ which I presume is the same source.
This site authored by Karl M. Syring. There are a number of utilities, the origin of some is given but there is no discussion of licence.
The source code is available through CVS attached to
http://sourceforge.net/projects/unxutilscvs -d:pserver:anonymous@cvs.sourceforge.net:/cvsroot/unxutils login
cvs -z3 -d:pserver:anonymous@cvs.sourceforge.net:/cvsroot/unxutils co -P unxutils
I have downloaded the source and the file utilities appear to be early GNU and are therefore freely distributable.
I enclose a header from the cp.c. There is however no copy of the the GNU General Public Licence.
If you made the source available it would seem ok to resdistribute
/* cp.c -- file copying (main routines)
Copyright (C) 89, 90, 91, 95, 1996 Free Software Foundation.
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; if not, write to the Free Software Foundation,
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
Written by Torbjorn Granlund, David MacKenzie, and Jim Meyering. */