NETHACK GENERAL PUBLIC LICENSE

                    (Copyright 1989 M. Stephenson)

               (Based on the BISON general public license,

                   copyright 1988 Richard M. Stallman)

 Everyone is permitted to copy and distribute verbatim copies of this

 license, but changing it is not allowed.  You can also use this wording to

 make the terms for other programs.

  The license agreements of most software companies keep you at the mercy of

those companies.  By contrast, our general public license is intended to give

everyone the right to share NetHack.  To make sure that you get the rights we

want you to have, we need to make restrictions that forbid anyone to deny you

these rights or to ask you to surrender the rights.  Hence this license

agreement.

  Specifically, we want to make sure that you have the right to give away

copies of NetHack, that you receive source code or else can get it if you

want it, that you can change NetHack or use pieces of it in new free

programs, and that you know you can do these things.

  To make sure that everyone has such rights, we have to forbid you to

deprive anyone else of these rights.  For example, if you distribute copies

of NetHack, you must give the recipients all the rights that you have.  You

must make sure that they, too, receive or can get the source code.  And you

must tell them their rights.

  Also, for our own protection, we must make certain that everyone finds out

that there is no warranty for NetHack.  If NetHack is modified by someone

else and passed on, we want its recipients to know that what they have is

not what we distributed.

  Therefore we (Mike Stephenson and other holders of NetHack copyrights) make

the following terms which say what you must do to be allowed to distribute or

change NetHack.

                        COPYING POLICIES

  1. You may copy and distribute verbatim copies of NetHack source code as

you receive it, in any medium, provided that you keep intact the notices on

all files that refer to copyrights, to this License Agreement, and to the

absence of any warranty; and give any other recipients of the NetHack

program a copy of this License Agreement along with the program.

  2. You may modify your copy or copies of NetHack or any portion of it, and

copy and distribute such modifications under the terms of Paragraph 1 above

(including distributing this License Agreement), provided that you also do the

following:

    a) cause the modified files to carry prominent notices stating that you

    changed the files and the date of any change; and

    b) cause the whole of any work that you distribute or publish, that in

    whole or in part contains or is a derivative of NetHack or any part

    thereof, to be licensed at no charge to all third parties on terms

    identical to those contained in this License Agreement (except that you

    may choose to grant more extensive warranty protection to some or all

    third parties, at your option)

    c) You may charge a distribution fee for the physical act of

    transferring a copy, and you may at your option offer warranty protection

    in exchange for a fee.

  3. You may copy and distribute NetHack (or a portion or derivative of it,

under Paragraph 2) in object code or executable form under the terms of

Paragraphs 1 and 2 above provided that you also do one of the following:

    a) accompany it with the complete machine-readable source code, which

    must be distributed under the terms of Paragraphs 1 and 2 above; or,

    b) accompany it with full information as to how to obtain the complete

    machine-readable source code from an appropriate archive site.  (This

    alternative is allowed only for noncommercial distribution.)

For these purposes, complete source code means either the full source

distribution as originally released over Usenet or updated copies of the

files in this distribution used to create the object code or executable.

  4. You may not copy, sublicense, distribute or transfer NetHack except as

expressly provided under this License Agreement.  Any attempt otherwise to

copy, sublicense, distribute or transfer NetHack is void and your rights to

use the program under this License agreement shall be automatically

terminated.  However, parties who have received computer software programs

from you with this License Agreement will not have their licenses terminated

so long as such parties remain in full compliance.

Stated plainly:  You are permitted to modify NetHack, or otherwise use parts

of NetHack, provided that you comply with the conditions specified above;

in particular, your modified NetHack or program containing parts of NetHack

must remain freely available as provided in this License Agreement.  In

other words, go ahead and share NetHack, but don't try to stop anyone else

from sharing it farther.