In short, Gauche is distributed under so called "BSD license",
that is, as far as you retain the copyrignt notice and disclaimer below,
you can use, copy, modify and redistribute your modification freely.
The formal term is specified in each copyright notices.

A few files associated to autoconf and libtool in the distribution are
covered by GPL, but they have an exception so that I (and you) can
distribute them under BSD license.  See each file for the detailed term.


Copyright and condition of use of main portion of the source:
-----------------------------------------------------------------------------

  Copyright (c) 2000-2006 Shiro Kawai, All rights reserved.

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions
  are met:

   1. Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.

   2. Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.

   3. Neither the name of the authors nor the names of its contributors
      may be used to endorse or promote products derived from this
      software without specific prior written permission.

  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

-----------------------------------------------------------------------------



Copyright of gc/* -----------------------------------------------------------

    Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
    Copyright (c) 1991-1996 by Xerox Corporation.  All rights reserved.
    Copyright (c) 1996-1999 by Silicon Graphics.  All rights reserved.
    Copyright (c) 1999 by Hewlett-Packard Company. All rights reserved.

    THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
    OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.

    Permission is hereby granted to use or copy this program
    for any purpose,  provided the above notices are retained on all copies.
    Permission to modify the code and to distribute modified code is granted,
    provided the above notices are retained, and a notice that the code was
    modified is included with the above copyright notice.


Copyright of lib/srfi-1.scm -------------------------------------------------

;;; Copyright (c) 1998, 1999 by Olin Shivers. You may do as you please with
;;; this code as long as you do not remove this copyright notice or
;;; hold me liable for its use. Please send bug reports to shivers@ai.mit.edu.


Copyright of lib/srfi-11.scm ------------------------------------------------

;;  Copyright (C) Lars T Hansen (1999). All Rights Reserved. 
;;
;;  This document and translations of it may be copied and furnished to
;;  others, and derivative works that comment on or otherwise explain it
;;  or assist in its implementation may be prepared, copied, published and
;;  distributed, in whole or in part, without restriction of any kind,
;;  provided that the above copyright notice and this paragraph are
;;  included on all such copies and derivative works. However, this
;;  document itself may not be modified in any way, such as by removing
;;  the copyright notice or references to the Scheme Request For
;;  Implementation process or editors, except as needed for the purpose of
;;  developing SRFIs in which case the procedures for copyrights defined
;;  in the SRFI process must be followed, or as required to translate it
;;  into languages other than English.
;;
;;  The limited permissions granted above are perpetual and will not be
;;  revoked by the authors or their successors or assigns.
;;
;;  This document and the information contained herein is provided on an
;;  "AS IS" basis and THE AUTHOR AND THE SRFI EDITORS DISCLAIM ALL
;;  WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY
;;  WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY
;;  RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A
;;  PARTICULAR PURPOSE.


Copyright of ext/mt-random/mt-random.c ------------------------------------

   Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,
   All rights reserved.                          

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

     1. Redistributions of source code must retain the above copyright
        notice, this list of conditions and the following disclaimer.

     2. Redistributions in binary form must reproduce the above copyright
        notice, this list of conditions and the following disclaimer in the
        documentation and/or other materials provided with the distribution.

     3. The names of its contributors may not be used to endorse or promote 
        products derived from this software without specific prior written 
        permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


Copyright of lib/gauche/reload.scm -------------------------------------

;;;  Copyright(C) 2002 by Alex Shinn <foof@synthcode.com>
;;;
;;;  Permission to use, copy, modify, distribute this software and
;;;  accompanying documentation for any purpose is hereby granted,
;;;  provided that existing copyright notices are retained in all
;;;  copies and that this notice is included verbatim in all
;;;  distributions.
;;;  This software is provided as is, without express or implied
;;;  warranty.  In no circumstances the author(s) shall be liable
;;;  for any damages arising out of the use of this software.


Copyright of ext/digest/*, lib/rfc/hmac.scm, lib/util/digest.scm -------

  Copyright (c) 2002-2003 Kimura Fuyuki, All rights reserved.

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions
  are met:

  1. Redistributions of source code must retain the above copyright
     notice, this list of conditions and the following disclaimer.

  2. Redistributions in binary form must reproduce the above copyright
     notice, this list of conditions and the following disclaimer in the
     documentation and/or other materials provided with the distribution.

  3. Neither the name of the authors nor the names of its contributors
     may be used to endorse or promote products derived from this
     software without specific prior written permission.

  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
