2003-02-18 Neal H. Walfield <[email protected]>

	* Makefile.am: New file.
	* fdl.texi: New file.
	* gpl.texi: New file.
	* assuan.texi: Imported from newpg.

5 files changed, 1207 insertions, 0 deletions

diff --git a/doc/ChangeLog b/doc/ChangeLog
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+2003-02-18  Neal H. Walfield  <[email protected]>
+
+	* Makefile.am: New file.
+	* fdl.texi: New file.
+	* gpl.texi: New file.
+	* assuan.texi: Imported from newpg.
+
diff --git a/doc/Makefile.am b/doc/Makefile.am
new file mode 100644
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--- /dev/null
+++ b/doc/Makefile.am
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+# Assuan Makefile
+# Copyright (C) 2003 Free Software Foundation, Inc.
+#
+# This file is part of Assuan.
+#
+# Assuan is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as
+# published by the Free Software Foundation; either version 2.1 of
+# the License, or (at your option) any later version.
+#
+# Assuan 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser 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 
+
+## Process this file with automake to produce Makefile.in
+
+info_TEXINFOS = assuan.texi
+
+assuan_TEXINFOS = gpl.texi fdl.texi
+
diff --git a/doc/assuan.texi b/doc/assuan.texi
new file mode 100644
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--- /dev/null
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+\input texinfo                      @c -*-texinfo-*-
+@c %**start of header
+@setfilename assuan.info
+
+@macro copyrightnotice
+Copyright @copyright{} 2002, 2003 Free Software Foundation, Inc.
+@end macro
+@macro permissionnotice
+Permission is granted to copy, distribute and/or modify this document
+under the terms of the GNU Free Documentation License, Version 1.1 or
+any later version published by the Free Software Foundation; with the
+Invariant Sections being ``GNU General Public License'', the Front-Cover
+texts being (a) (see below), and with the Back-Cover Texts being (b)
+(see below).  A copy of the license is included in the section entitled
+``GNU Free Documentation License''.
+
+(a) The FSF's Front-Cover Text is:
+
+     A GNU Manual
+
+(b) The FSF's Back-Cover Text is:
+
+     You have freedom to copy and modify this GNU Manual, like GNU
+     software.  Copies published by the Free Software Foundation raise
+     funds for GNU development.
+@end macro
+
+
+@settitle Developing with Assuan
+
+@c Create a separate index for command line options.
+@defcodeindex op
+@c Merge the standard indexes into a single one.
+@syncodeindex fn cp
+@syncodeindex vr cp
+@syncodeindex ky cp
+@syncodeindex pg cp
+@syncodeindex tp cp
+
+@c printing stuff taken from gcc.
+@macro gnupgtabopt{body}
+@code{\body\}
+@end macro
+@macro gnupgoptlist{body}
+@smallexample
+\body\
+@end smallexample
+@end macro
+@c Makeinfo handles the above macro OK, TeX needs manual line breaks;
+@c they get lost at some point in handling the macro.  But if @macro is
+@c used here rather than @alias, it produces double line breaks.
+@iftex
+@alias gol = *
+@end iftex
+@ifnottex
+@macro gol
+@end macro
+@end ifnottex
+
+
+@c Change the font used for @def... commands, since the default
+@c proportional one used is bad for names starting __.
+@tex
+\global\setfont\defbf\ttbshape{10}{\magstep1}
+@end tex
+
+@c %**end of header
+
+@ifnottex
+@dircategory GNU Libraries
+@direntry
+* Assuan: (assuan).        An IPC library for non-persistent servers.
+@end direntry
+This file documents the use and the internals of Assuan.
+
+This is Edition @value{EDITION}, last updated @value{UPDATED}, of
+@cite{The `Developing with Assuan' Manual}, for Version @value{VERSION}.
+@sp 1
+Published by the Free Software Foundation@*
+59 Temple Place - Suite 330@*
+Boston, MA 02111-1307 USA
+@sp 1
+@copyrightnotice{}
+@sp 1
+@permissionnotice{}
+@end ifnottex
+
+@setchapternewpage odd
+
+@titlepage
+@title Developing with Assuan
+@subtitle Version @value{VERSION}
+@subtitle @value{UPDATED}
+@author Werner Koch @code{(wk@@gnupg.org)}
+
+@page
+@vskip 0pt plus 1filll
+@copyrightnotice{}
+@sp 2
+@permissionnotice{}
+@end titlepage
+@summarycontents
+@contents
+@page
+
+
+@node Top
+@top Introduction
+@cindex introduction
+
+This manual documents how to exploit the Assuan library, a simple
+interprocess communcation library.
+
+@menu
+* Introduction::        An introduction to and the motivation behind Assuan.
+* Assuan::              Description of the Assuan protocol.
+
+Miscellaneous
+
+* Copying::             GNU Lesser General Public License says
+                        how you can copy and share Assuan
+* GNU Free Documentation License:: How you can copy and share this manual.
+
+Indices
+
+* Option Index::        Index to command line options.
+* Index::	        Index of concepts and symbol names.
+@end menu
+
+@include gpl.texi
+@include fdl.texi
+
+@node Introduction
+@chapter Introduction to Assuan
+
+In an ideal world, Assuan is irrelevant.  Assuan's primary use is to
+allow a client to interact with a non-persistent server.  Using
+Assuan, this is accomplished by forking a subprocess and communicating
+with it via, for example, a pipe or unix domain socket.  This method
+is neither elegant nor efficient especially when there is a lot of
+data spread across several transactions: not only is there a penalty
+for an increased number of context switches, but also a significant
+amount of data is @var{memcpy}ed from the client to a file descriptor
+and from the file descriptor to the server.  Despite these and other
+disadvantages, this type of client/server communication can be useful:
+the client is completely separate from the server; they are in
+different address spaces.  This is especially important in situations
+where the server must have a known degree of reliability and data must
+be protected: as the Assuan protocol is well defined and clients
+cannot corrupt the servers' address space, auditing become much
+easier.
+
+Assuan was developed for use by the GNU Privacy Guard, GnuPG, to
+prevent potentially buggy clients from unwittingly corrupting
+sensitive transactions or compromising data such as a secret key.
+Assuan permits the servers, which do the actual work, e.g. encryption
+and decryption of data using a secret key, to be developed
+independently of the user interfaces, e.g. mail clients and other
+encryption front ends.  Like a shared library, the interface is well
+defined and any number of front ends can use it; however, unlike a
+shared library, the client cannot see or touch the server's data.  As
+with any modular system, Assuan helps keep the servers small and
+understandable help to make code more understandable and less error
+prone.
+
+Assuan is not, however, limited to use with GnuPG servers and clients:
+it was design to be flexible enough to meet the demands of almost any
+transaction based environment with non-persistent servers.
+
+@node Assuan
+@chapter Description of the Assuan protocol.
+
+The architecture of the modular GnuPG system is based on several
+highly specialized modules which compose a network of client/server
+communication.  A common framework for intermodule communication is
+therefore needed and should be implemented in a library.
+
+Goals:
+
+@itemize @bullet
+@item Common framework for module communication
+@item Easy debugging
+@item Easy module testing 
+@item Extendible
+@item Optional authentication and encryption facility
+@item Usable by access external hardware
+@end itemize
+
+
+Design criteria:
+
+@itemize @bullet
+@item Client server with back channel
+@item Use a mainly text based protocol
+@item Escape certain control characters
+@item Allow indefinite data length
+@item Request confidentiality for parts of the communication
+@item Dummy module to allow direct linking of client and server
+@item Inline data or descriptor passing for bulk data
+@item No protection against DoS needed
+@item Subliminal channels are not an issue
+@end itemize
+
+Implementation:
+
+The implementation is line based with a maximum line size of 1000
+octects.  The default IPC mechanism are Unix Domain Sockets.
+
+On a connect request the server responds either with an okay or an error
+status.  For authentication check the server may send an Inquiry
+Response prior to the first Okay, it may also issue Status messages.
+The server must check that the client is allowed to connect, this is
+done by requesting the credentials for the peer and comparing them to
+those of the server.  This avoids attacks based on wrong socket
+permissions.
+
+It may choose to delay the first response in case of an error.  The
+server never closes the connection - however the lower protocol may do
+so after some time of inactivity or when the connection is in an error
+state.
+
+All textual messages are assumed to be in UTF-8 unless otherwise noted.
+
+
+Server responses:
+
+@table @code
+@item OK  [<arbitary debugging information>]
+Request was successful.
+
+@item ERR @var{errorcode} [<human readable error description>]
+Request could not be fulfilled.  The error codes are mostly application
+specific except for a few common ones.
+
+@item S @var{keyword} <status information depending on keyword>
+Informational output by the server, still processing the request.
+
+@item # <string>
+Comment line issued only for debugging purposes.  Totally ignored.
+
+@item D <raw data>
+Raw data returned to client. There must be exactly one space after the
+'D'.  The values for '%', CR and LF must be percent escaped; this is
+encoded as %25, %0D and %0A.  Only uppercase letters should be used in
+the hexadecimal representation.  Other characters may be percent escaped
+for easier debugging.  All these Data lines are considered one data
+stream up to the OK or ERR response.  Status and Inquiry Responses
+may be mixed with the Data lines.
+
+@item INQUIRE @var{keyword}> <parameters>
+Server needs further information from the client.  The client should
+answer with a command which is allowed after an inquiry.  Note that the
+server does not confirm that client command but either continues
+processing or ends processing with an error status.  Not all commands
+are allowed.
+@end table
+
+
+A client should only check the first letter of each line and then skip
+over to the next token (except for data lines where the raw data starts
+exactly after 2 bytes).  Lines larger than 1000 bytes should be
+treated as a communication error. (The rationale for having a line
+length limit is to allow for easier multiplexing of multiple channels).
+
+
+Client requests:
+
+The server waits for client requests after he sent an Okay or Error.
+The client should not issue a request in other cases with the
+exception of the CANCEL command.
+
+@example
+@var{command} <parameters>
+@end example
+
+@var{command} is a one word string without preceding white space.
+Parameters are command specific, CR, LF and the percent signs should be
+percent escaped as described above.  To send a backslash as the last
+character it should also be percent escaped.  Percent escaping is
+allowed anywhere in the parameters but not in the command.  The line
+ends with a CR, LF or just a LF.
+
+Not yet implemented feature: If there is a need for a parameter list
+longer than the line length limit (1000 characters including command and
+CR, LF), the last character of the line (right before the CR/LF or LF)
+must be a non-escape encoded backslash. The following line is then
+expected to be a continuation of the line with the backslash replaced by
+a blank and the line ending removed.
+
+@example
+D <raw data>
+@end example
+
+Raw data to the server. There must be exactly one space after the 'D'.
+The values for '%', CR and LF must be percent escaped; this is encoded
+as %25, %0D and %0A.  Only uppercase letters should be used in the
+hexadecimal representation.  Other characters may be percent escaped for
+easier debugging.  All these Data lines are considered one data stream
+up to the OKAY or ERROR response.  Status and Inquiry Responses may be
+mixed with the Data lines.
+
+@example
+END
+@end example
+
+
+
+Lines beginning with a @code{#} or empty lines are ignored.  This is
+useful to comment test scripts.
+
+
+Although the commands are application specific, some of them are used by
+all protocols and partly directly supported by the Assuan library:
+
+@table @code
+@item CANCEL
+his is the one special command which aborts the current request.  it can
+be sent at any time and the server will stop its operation right before
+it would send the next response line (of any type).
+
+@item BYE
+Close the connect, the server will reply with an @code{OK}.
+
+@item AUTH
+Not yet specified as we don't implement it in the first phase.  See my
+mail to gpa-dev on 2001-10-25 about the rationale for measurements
+against local attacks.
+
+@item RESET
+Reset the connection but not any existing authentication.  The server
+should release all resources associated with the connection.
+
+@item END
+Used by a client to mark the end of raw data.  The server may send END
+to indicate a partial end of data.
+@end table
+
+
+Error Codes:
+
+Here we keep a list of error codes used in any Assuan based
+protocol.  The format is the string @code{ERR}, white space, the error
+number, white space, a textual description of the error.
+
+@table @code
+
+@item 100 Unknown Command
+@item 101 Not Implemented
+
+@item 301 certificate has been revoked [DirMngr]
+@item 302 no CRL known for this certificate [DirMngr]
+@item 303 CRL is too old and a new one could not be retrieved [DirMngr]
+
+@end table
+
+
+@c ---------------------------------------------------------------------
+@c Indexes
+@c ---------------------------------------------------------------------
+
+@node Option Index
+@unnumbered Option Index
+
+@printindex op
+
+@node Index
+@unnumbered Index
+
+@printindex cp
+
+@c ---------------------------------------------------------------------
+@c Epilogue
+@c ---------------------------------------------------------------------
+
+@bye
+
+
diff --git a/doc/fdl.texi b/doc/fdl.texi
new file mode 100644
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--- /dev/null
+++ b/doc/fdl.texi
@@ -0,0 +1,401 @@
+@node GNU Free Documentation License
+@appendix GNU Free Documentation License
+
+@cindex FDL, GNU Free Documentation License
+@center Version 1.1, March 2000
+
+@display
+Copyright @copyright{} 2000 Free Software Foundation, Inc.
+59 Temple Place, Suite 330, Boston, MA  02111-1307, USA
+
+Everyone is permitted to copy and distribute verbatim copies
+of this license document, but changing it is not allowed.
+@end display
+
+@enumerate 0
+@item
+PREAMBLE
+
+The purpose of this License is to make a manual, textbook, or other
+written document @dfn{free} in the sense of freedom: to assure everyone
+the effective freedom to copy and redistribute it, with or without
+modifying it, either commercially or noncommercially.  Secondarily,
+this License preserves for the author and publisher a way to get
+credit for their work, while not being considered responsible for
+modifications made by others.
+
+This License is a kind of ``copyleft'', which means that derivative
+works of the document must themselves be free in the same sense.  It
+complements the GNU General Public License, which is a copyleft
+license designed for free software.
+
+We have designed this License in order to use it for manuals for free
+software, because free software needs free documentation: a free
+program should come with manuals providing the same freedoms that the
+software does.  But this License is not limited to software manuals;
+it can be used for any textual work, regardless of subject matter or
+whether it is published as a printed book.  We recommend this License
+principally for works whose purpose is instruction or reference.
+
+@item
+APPLICABILITY AND DEFINITIONS
+
+This License applies to any manual or other work that contains a
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+A ``Modified Version'' of the Document means any work containing the
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+The ``Invariant Sections'' are certain Secondary Sections whose titles
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+
+@item
+VERBATIM COPYING
+
+You may copy and distribute the Document in any medium, either
+commercially or noncommercially, provided that this License, the
+copyright notices, and the license notice saying this License applies
+to the Document are reproduced in all copies, and that you add no other
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+
+You may also lend copies, under the same conditions stated above, and
+you may publicly display copies.
+
+@item
+COPYING IN QUANTITY
+
+If you publish printed copies of the Document numbering more than 100,
+and the Document's license notice requires Cover Texts, you must enclose
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+
+If the required texts for either cover are too voluminous to fit
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+
+If you publish or distribute Opaque copies of the Document numbering
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+
+It is requested, but not required, that you contact the authors of the
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+
+@item
+MODIFICATIONS
+
+You may copy and distribute a Modified Version of the Document under
+the conditions of sections 2 and 3 above, provided that you release
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+
+@enumerate A
+@item
+Use in the Title Page (and on the covers, if any) a title distinct
+from that of the Document, and from those of previous versions
+(which should, if there were any, be listed in the History section
+of the Document).  You may use the same title as a previous version
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+
+@item
+List on the Title Page, as authors, one or more persons or entities
+responsible for authorship of the modifications in the Modified
+Version, together with at least five of the principal authors of the
+Document (all of its principal authors, if it has less than five).
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+@item
+State on the Title page the name of the publisher of the
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+
+@item
+Preserve all the copyright notices of the Document.
+
+@item
+Add an appropriate copyright notice for your modifications
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+Include, immediately after the copyright notices, a license notice
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+Preserve in that license notice the full lists of Invariant Sections
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+Include an unaltered copy of this License.
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+Preserve the section entitled ``History'', and its title, and add to
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+
+@item
+Preserve the network location, if any, given in the Document for
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+
+@item
+In any section entitled ``Acknowledgments'' or ``Dedications'',
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+
+@item
+Preserve all the Invariant Sections of the Document,
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+Delete any section entitled ``Endorsements''.  Such a section
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+
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+Do not retitle any existing section as ``Endorsements''
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+
+@item
+COMBINING DOCUMENTS
+
+You may combine the Document with other documents released under this
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+
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+author or publisher of that section if known, or else a unique number.
+Make the same adjustment to the section titles in the list of
+Invariant Sections in the license notice of the combined work.
+
+In the combination, you must combine any sections entitled ``History''
+in the various original documents, forming one section entitled
+``History''; likewise combine any sections entitled ``Acknowledgments'',
+and any sections entitled ``Dedications''.  You must delete all sections
+entitled ``Endorsements.''
+
+@item
+COLLECTIONS OF DOCUMENTS
+
+You may make a collection consisting of the Document and other documents
+released under this License, and replace the individual copies of this
+License in the various documents with a single copy that is included in
+the collection, provided that you follow the rules of this License for
+verbatim copying of each of the documents in all other respects.
+
+You may extract a single document from such a collection, and distribute
+it individually under this License, provided you insert a copy of this
+License into the extracted document, and follow this License in all
+other respects regarding verbatim copying of that document.
+
+@item
+AGGREGATION WITH INDEPENDENT WORKS
+
+A compilation of the Document or its derivatives with other separate
+and independent documents or works, in or on a volume of a storage or
+distribution medium, does not as a whole count as a Modified Version
+of the Document, provided no compilation copyright is claimed for the
+compilation.  Such a compilation is called an ``aggregate'', and this
+License does not apply to the other self-contained works thus compiled
+with the Document, on account of their being thus compiled, if they
+are not themselves derivative works of the Document.
+
+If the Cover Text requirement of section 3 is applicable to these
+copies of the Document, then if the Document is less than one quarter
+of the entire aggregate, the Document's Cover Texts may be placed on
+covers that surround only the Document within the aggregate.
+Otherwise they must appear on covers around the whole aggregate.
+
+@item
+TRANSLATION
+
+Translation is considered a kind of modification, so you may
+distribute translations of the Document under the terms of section 4.
+Replacing Invariant Sections with translations requires special
+permission from their copyright holders, but you may include
+translations of some or all Invariant Sections in addition to the
+original versions of these Invariant Sections.  You may include a
+translation of this License provided that you also include the
+original English version of this License.  In case of a disagreement
+between the translation and the original English version of this
+License, the original English version will prevail.
+
+@item
+TERMINATION
+
+You may not copy, modify, sublicense, or distribute the Document except
+as expressly provided for under this License.  Any other attempt to
+copy, modify, sublicense or distribute the Document is void, and will
+automatically terminate your rights under this License.  However,
+parties who have received copies, or rights, from you under this
+License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+@item
+FUTURE REVISIONS OF THIS LICENSE
+
+The Free Software Foundation may publish new, revised versions
+of the GNU Free Documentation License from time to time.  Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.  See
+@uref{http://www.gnu.org/copyleft/}.
+
+Each version of the License is given a distinguishing version number.
+If the Document specifies that a particular numbered version of this
+License ``or any later version'' applies to it, you have the option of
+following the terms and conditions either of that specified version or
+of any later version that has been published (not as a draft) by the
+Free Software Foundation.  If the Document does not specify a version
+number of this License, you may choose any version ever published (not
+as a draft) by the Free Software Foundation.
+@end enumerate
+
+@page
+@appendixsubsec ADDENDUM: How to use this License for your documents
+
+To use this License in a document you have written, include a copy of
+the License in the document and put the following copyright and
+license notices just after the title page:
+
+@smallexample
+@group
+  Copyright (C)  @var{year}  @var{your name}.
+  Permission is granted to copy, distribute and/or modify this document
+  under the terms of the GNU Free Documentation License, Version 1.1
+  or any later version published by the Free Software Foundation;
+  with the Invariant Sections being @var{list their titles}, with the
+  Front-Cover Texts being @var{list}, and with the Back-Cover Texts being @var{list}.
+  A copy of the license is included in the section entitled ``GNU
+  Free Documentation License''.
+@end group
+@end smallexample
+
+If you have no Invariant Sections, write ``with no Invariant Sections''
+instead of saying which ones are invariant.  If you have no
+Front-Cover Texts, write ``no Front-Cover Texts'' instead of
+``Front-Cover Texts being @var{list}''; likewise for Back-Cover Texts.
+
+If your document contains nontrivial examples of program code, we
+recommend releasing these examples in parallel under your choice of
+free software license, such as the GNU General Public License,
+to permit their use in free software.
+
+@c Local Variables:
+@c ispell-local-pdict: "ispell-dict"
+@c End:
diff --git a/doc/gpl.texi b/doc/gpl.texi
new file mode 100644
index 0000000..ca0508f
--- /dev/null
+++ b/doc/gpl.texi
@@ -0,0 +1,397 @@
+@node Copying
+@appendix GNU GENERAL PUBLIC LICENSE
+
+@cindex GPL, GNU General Public License
+@center Version 2, June 1991
+
+@display
+Copyright @copyright{} 1989, 1991 Free Software Foundation, Inc.
+59 Temple Place -- Suite 330, Boston, MA 02111-1307, USA
+
+Everyone is permitted to copy and distribute verbatim copies
+of this license document, but changing it is not allowed.
+@end display
+
+@appendixsubsec Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software---to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, 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 show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+@iftex
+@appendixsubsec TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+@end iftex
+@ifinfo
+@center TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+@end ifinfo
+
+@enumerate
+@item
+This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The ``Program'', below,
+refers to any such program or work, and a ``work based on the Program''
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term ``modification''.)  Each licensee is addressed as ``you''.
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+@item
+You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+@item
+You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+@enumerate a
+@item
+You must cause the modified files to carry prominent notices
+stating that you changed the files and the date of any change.
+
+@item
+You must cause any work that you distribute or publish, that in
+whole or in part contains or is derived from the Program or any
+part thereof, to be licensed as a whole at no charge to all third
+parties under the terms of this License.
+
+@item
+If the modified program normally reads commands interactively
+when run, you must cause it, when started running for such
+interactive use in the most ordinary way, to print or display an
+announcement including an appropriate copyright notice and a
+notice that there is no warranty (or else, saying that you provide
+a warranty) and that users may redistribute the program under
+these conditions, and telling the user how to view a copy of this
+License.  (Exception: if the Program itself is interactive but
+does not normally print such an announcement, your work based on
+the Program is not required to print an announcement.)
+@end enumerate
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+@item
+You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+@enumerate a
+@item
+Accompany it with the complete corresponding machine-readable
+source code, which must be distributed under the terms of Sections
+1 and 2 above on a medium customarily used for software interchange; or,
+
+@item
+Accompany it with a written offer, valid for at least three
+years, to give any third party, for a charge no more than your
+cost of physically performing source distribution, a complete
+machine-readable copy of the corresponding source code, to be
+distributed under the terms of Sections 1 and 2 above on a medium
+customarily used for software interchange; or,
+
+@item
+Accompany it with the information you received as to the offer
+to distribute corresponding source code.  (This alternative is
+allowed only for noncommercial distribution and only if you
+received the program in object code or executable form with such
+an offer, in accord with Subsection b above.)
+@end enumerate
+
+The source code for a work means the preferred form of the work for
+making modifications to it.  For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable.  However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+@item
+You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+@item
+You are not required to accept this License, since you have not
+signed it.  However, nothing else grants you permission to modify or
+distribute the Program or its derivative works.  These actions are
+prohibited by law if you do not accept this License.  Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+@item
+Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+@item
+If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+@item
+If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+@item
+The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and ``any
+later version'', you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+@item
+If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission.  For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+@iftex
+@heading NO WARRANTY
+@end iftex
+@ifinfo
+@center NO WARRANTY
+@end ifinfo
+
+@item
+BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM ``AS IS'' WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+@item
+IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+@end enumerate
+
+@iftex
+@heading END OF TERMS AND CONDITIONS
+@end iftex
+@ifinfo
+@center END OF TERMS AND CONDITIONS
+@end ifinfo
+
+@page
+@unnumberedsec How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the ``copyright'' line and a pointer to where the full notice is found.
+
+@smallexample
+@var{one line to give the program's name and an idea of what it does.}
+Copyright (C) 19@var{yy}  @var{name of author}
+
+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
+of the License, 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.
+@end smallexample
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+@smallexample
+Gnomovision version 69, Copyright (C) 19@var{yy} @var{name of author}
+Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
+type `show w'.  This is free software, and you are welcome
+to redistribute it under certain conditions; type `show c' 
+for details.
+@end smallexample
+
+The hypothetical commands @samp{show w} and @samp{show c} should show
+the appropriate parts of the General Public License.  Of course, the
+commands you use may be called something other than @samp{show w} and
+@samp{show c}; they could even be mouse-clicks or menu items---whatever
+suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a ``copyright disclaimer'' for the program, if
+necessary.  Here is a sample; alter the names:
+
+@smallexample
+@group
+Yoyodyne, Inc., hereby disclaims all copyright
+interest in the program `Gnomovision'
+(which makes passes at compilers) written 
+by James Hacker.
+
+@var{signature of Ty Coon}, 1 April 1989
+Ty Coon, President of Vice
+@end group
+@end smallexample
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.