LICENSE

  Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted, provided
that the above copyright notice appears in all copies and that both the
copyright notice and this permission notice appear in supporting
documentation, and that the same name not be used in advertising or
publicity pertaining to distribution of the software without specific,
written prior permission. We make no representations about the
suitability this software for any purpose. It is provided "as is"
without express or implied warranty.

CREDITS

  sort: coreutils, Copyright (C) 1988, 1991-2010 Free Software Foundation, Inc.,
licensed under the GNU General Public License (http://www.gnu.org/licenses/gpl.html).
(http://www.gnu.org/software/coreutils)

  shlock: shlock.c, Copyright (c) 2005 The DragonFly Project,
licensed under the DragonFly BSD License (http://www.dragonflybsd.org/docs/developer/DragonFly_BSD_License/).
(http://gitweb.dragonflybsd.org/dragonfly.git/blob/HEAD:/usr.bin/shlock/shlock.c)