Dezyne IDE Manual

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Dezyne-IDE

This document describes the Dezyne IDE version 2.10.0.rc13.2-fba6.


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1 Introduction

While the component-based approach of Dezyne (see Dezyne Reference Manual) helps to create an understandable, modular system architecture, working on a software system is not always easy. When the problem at hand gets more difficult, then all help, e.g., help from tooling, is welcome.

Working with the Dezyne Language, we think, is best done using the Dezyne IDE.

The Dezyne IDE provides two graphical views: a structural overview (see System View) that helps navigating the system architecture, and a dynamic view (see Trace View) that helps understanding your system’s behaviour.

The Dezyne IDE consists of these elements:

We provide a reference implementation for this: dezyne (see dezyne the IDE) that combines the Dezyne Language-Aware editor, the graphical views and the console and integrates these using GNU Guile (see Using Guile in Emacs in GNU Guile Reference Manual) into a pleasant, fully user-extensible, experience.


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2 Getting Started

The dezyne core functionality delivers tool support for the dezyne language in parsing, verification and code generation. Results are delivered in text format only.

In order to gain more insight graphical feedback is delivered in the following cases:

All views are initiated by the user from the command-line, and are presented in a web page.


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2.1 Set-up

In order to use the web views a dedicated dzn daemon needs to be running. This daemon mediates between the command line and the web pages, and also stores the traces that are presented and modified in the sequence view.

For the time being the dzn daemon must be started by hand. It will keep running until it is aborted by the user. It is started by typing the command

dzn daemon

The expected response is

ide_port: 1024
view_port: 1025
setup done

For more details try dzn daemon --help, or see Invoking dzn daemon.

Once the daemon is running, views can be initiated.


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2.2 System View

The system view is started from the command-line with the command

dzn system examples/Camera.dzn

The expected result is

setup done

initialization done
file://<PATH>/dzn/system.html

Opening the provided system.html page in a web browser delivers the system view of the Camera component.

For more details try dzn system --help, or see Invoking dzn system.


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2.3 Sequence view and Watch window

The sequence view and watch window can be initiated from the command-line uing the dzn simulate command:

dzn simulate -m Driver examples/Camera.dzn

Expected resonse is:

setup done

initialization done
file://<PATH>/dzn/trace.html
file://<PATH>/dzn/watch.html

Opening the provided trace.html and watch.html pages in a web browser delivers the views of the Driver sub component.

Optional input for the sequence view is a trace, which (among others) can be the result of a verification error. The dzn check command supports this scenario. As first step verification is done. In case an error is found, the error trace is used as input for simulation, and presented in the web views:

dzn check examples/compliance_provides_bool.dzn

results in:

verify: ibool: check: deadlock: ok
verify: ibool: check: livelock: ok
verify: compliance_provides_bool: check: deterministic: ok
verify: compliance_provides_bool: check: illegal: ok
verify: compliance_provides_bool: check: deadlock: ok
verify: compliance_provides_bool: check: livelock: ok
verify: compliance_provides_bool: check: compliance: fail
verification error

initialization done
file://<PATH>/dzn/trace.html
file://<PATH>/dzn/watch.html

For more details try dzn check --help and dzn simulate --help, or see Invoking dzn check and Invoking dzn simulate.


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3 Using the Dezyne IDE

While the letter I in IDE stands for integrated, the level and type of integration that makes a person productive is a matter of taste, habit and experience.

The Dezyne IDE offers these levels towards integration (or if you like, desintegration):

Full

Integrated: Editor, Browser, Console, Window Management, Interpreter

Examples are dezyne, or emacs with exwm

External Browser, External Window Mangement

Integrated: Editor, Console, Interpreter

Examples are Electron-derivatives, emacs, vim

External, Console, Browser, Window Management and Interpreter

Integrated: -

Examples are nano, vi.


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3.1 Example IDEs

Dezyne Language-Awareness is provided through the dzn daemon. Currently, it provides the following

Syntax coloring
Navigation

Go to definition, Show usage

Symbol completion
Lookup Documentation

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3.1.1 dezyne: the IDE

XXX TODO

The dezyne program provides a refererence implementation of a fully integrated Dezyne-IDE.

See Invoking dezyne.


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3.1.2 An Electron-based Dezyne-IDE

XXX FIXME

There are several Electron-based programmer’s editors: Atom, VSCodium and Microsoft’s non-free version: Visual Studio Code.

The dzn daemon provides Language-Awareness to the editor through the LSP-protocol.


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3.1.3 An Emacs-based Dezyne-IDE

Emacs can be used in Full or External Browser mode. dzn-mode.el.

Through the dzn daemon Emacs can provide full Dezyne Language-Awareness.

XXX TODO

images/Dezyne-IDE-GNU-Emacs-info-40 images/Dezyne-GNU-IDE-Emacs-Camera-verify-40

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3.2 Invoking dezyne

The dezyne command starts the Dezyne IDE: an integrated Dezyne viewer, console and browser.

dezyne optionFILE

The options can be among the following:

--check
-c

After loading FILE, run dzn check.

--editor-port=EDITOR-PORT
-e EDITOR-PORT

The editor will listen on the editor port EDITOR-PORT for interaction with Dezyne Views, the default is 1026.

--debug
-d

Enable debug ouput.

--help
-h

Display help on invoking dezyne, and then exit.

--ide-port=IDE-PORT
-i IDE-PORT

The daemon will listen on the ide port IDE-PORT, the default is 1024.

--import=DIR
-I DIR

Add directory DIR to import path.

--view-port=VIEW-PORT
-b VIEW-PORT

The daemon will listen on view port VIEW-PORT, the default is 1025.

--verbose
-v

Be more verbose, show progress.

--version
-V

Display the current version of dezyne, and then exit.

Note that currently, dezyne only supports loading one FILE.


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3.3 Dezyne IDE View Commands

The View experience of Dezyne IDE is achieved through a the dzn daemon and three sub-commands dzn check, dzn system, and dzn simulate.

Usually, your Dezyze IDE takes care of running these commands; so if you are planning on using an IDE you can safely skip this section.


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3.3.1 Invoking dzn daemon

All Dezyne View commands communicate with the Views and Editor through the dzn daemon. Before using a dzn-view command, the daemon must be started. Usually the Dezyne IDE will run a dzn daemon for you upon startup.

dzn dzn-option… daemon optionFILE

The options can be among the following:

--debug
-d

Enable debug ouput. Careful, this can produce a lot of text!

--help
-h

Display help on invoking dzn daemon, and then exit.

--ide-port=IDE-PORT
-i IDE-PORT

Listen to ide port IDE-PORT, the default is 1024.

--view-port=VIEW-PORT
-b VIEW-PORT

Listen to ide port VIEW-PORT, the default is 1025.

--verbose
-v

Be more verbose, show progress.


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3.3.2 Invoking dzn check

The dzn check command runs the dzn verify command. If verification errors are found, the dzn daemon provides a sequence view that can be viewed with a browser.

dzn dzn-option… check optionFILE

Running

dzn check compliance_provides_bool.dzn

will have the trace.html view show

images/dzn-check-compliance_provides_bool

The options can be among the following:

--import=DIR
-I DIR

Add directory DIR to import path.

--help
-h

Display help on invoking dzn check, and then exit.

--model=MODEL
-m MODEL

Limit verification to MODEL, and for behavioural component model, to its interfaces.

XXX: Verification cannot be limited to system components models; verifying a system model is a no-op. XXX

--port=PORT
-p PORT

Connect to IDE port PORT, the default is 1024.

--queue_size=SIZE
-q SIZE

Use queue size SIZE for verification, the default is 3.

XXX: queue_size is actually not supported yet XXX XXX: the underscore in –queue_size is weirdXXX

--verbose
-v

Be more verbose, show progress.


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3.3.3 Invoking dzn system

The dzn system command runs the dzn parse command. It produces an AST to the dzn daemon to provide a system vew can be viewed with a browser.

dzn dzn-option… system optionFILE

Running

dzn check Camera.dzn

will have the system.html view show

images/dzn-system-camera

The options can be among the following:

--import=DIR
-I DIR

Add directory DIR to import path.

--help
-h

Display help on invoking dzn system, and then exit.

--port=PORT
-p PORT

Connect to IDE port PORT, the default is 1024.

--verbose
-v

Be more verbose, show progress.


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3.4 Component Simulator

Input for the component simulator is a trace of events of a single component and its ports; such a trace is either a witness of a verification error, or a hand-crafted use case description. The simulator interprets the trace, using the Dezyne semantics, and outputs a more detailed trace, where the state of the component and its interfaces is included. It also outputs a list of ’eligible’ events: events that are a valid extension of the input trace.


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4 Dezyne Views


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4.1 System View

The system view shows a static view of a system component and all its sub components.

images/dzn-system-camera

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4.2 Trace View

images/dzn-check-compliance_provides_bool

The Trace View and Watch Window are used to visualize a detailed trace resulting from the component simulator; the Trace View displays all events that are communicated, and displays the eligible events; the watch window shows the value of all state variables; both views enable ’stepping’ through the trace in more or less detail. The Trace View can be used to extend the trace by selecting one of the eligible events.


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5 Working with Legacy Code

XXX: TODO


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5.1 ASD Converter

The semantics of ASD and Dezyne largely overlap. This enables automatic conversion from ASD models to Dezyne models. Work has to be done for multi-threaded ASD models. Also the readability of the generated Dezyne models needs improvement.


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Index

Jump to:   A   C   E   G   S   T  
Index Entry  Section

A
ASD: ASD Converter
automatic conversion: ASD Converter

C
conversion: ASD Converter

E
eligible events: Trace View

G
glue code: ASD Converter

S
sequence chart: Trace View
sequence view: Trace View
system architecture: System View
system view: System View

T
trace view: Trace View

Jump to:   A   C   E   G   S   T  

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Appendix A GNU Free Documentation License

Version 1.3, 3 November 2008
Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
http://fsf.org/

Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
  1. PREAMBLE

    The purpose of this License is to make a manual, textbook, or other functional and useful document 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.

  2. APPLICABILITY AND DEFINITIONS

    This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The “Document”, below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as “you”. You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law.

    A “Modified Version” of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language.

    A “Secondary Section” is a named appendix or a front-matter section of the Document that deals exclusively with the relationship of the publishers or authors of the Document to the Document’s overall subject (or to related matters) and contains nothing that could fall directly within that overall subject. (Thus, if the Document is in part a textbook of mathematics, a Secondary Section may not explain any mathematics.) The relationship could be a matter of historical connection with the subject or with related matters, or of legal, commercial, philosophical, ethical or political position regarding them.

    The “Invariant Sections” are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License. If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. The Document may contain zero Invariant Sections. If the Document does not identify any Invariant Sections then there are none.

    The “Cover Texts” are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License. A Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words.

    A “Transparent” copy of the Document means a machine-readable copy, represented in a format whose specification is available to the general public, that is suitable for revising the document straightforwardly with generic text editors or (for images composed of pixels) generic paint programs or (for drawings) some widely available drawing editor, and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters. A copy made in an otherwise Transparent file format whose markup, or absence of markup, has been arranged to thwart or discourage subsequent modification by readers is not Transparent. An image format is not Transparent if used for any substantial amount of text. A copy that is not “Transparent” is called “Opaque”.

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    The “Title Page” means, for a printed book, the title page itself, plus such following pages as are needed to hold, legibly, the material this License requires to appear in the title page. For works in formats which do not have any title page as such, “Title Page” means the text near the most prominent appearance of the work’s title, preceding the beginning of the body of the text.

    The “publisher” means any person or entity that distributes copies of the Document to the public.

    A section “Entitled XYZ” means a named subunit of the Document whose title either is precisely XYZ or contains XYZ in parentheses following text that translates XYZ in another language. (Here XYZ stands for a specific section name mentioned below, such as “Acknowledgements”, “Dedications”, “Endorsements”, or “History”.) To “Preserve the Title” of such a section when you modify the Document means that it remains a section “Entitled XYZ” according to this definition.

    The Document may include Warranty Disclaimers next to the notice which states that this License applies to the Document. These Warranty Disclaimers are considered to be included by reference in this License, but only as regards disclaiming warranties: any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License.

  3. 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 conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in section 3.

    You may also lend copies, under the same conditions stated above, and you may publicly display copies.

  4. COPYING IN QUANTITY

    If you publish printed copies (or copies in media that commonly have printed covers) of the Document, numbering more than 100, and the Document’s license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The front cover must present the full title with all words of the title equally prominent and visible. You may add other material on the covers in addition. Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects.

    If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages.

    If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a computer-network location from which the general network-using public has access to download using public-standard network protocols a complete Transparent copy of the Document, free of added material. If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public.

    It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document.

  5. 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 the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:

    1. 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 if the original publisher of that version gives permission.
    2. 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 fewer than five), unless they release you from this requirement.
    3. State on the Title page the name of the publisher of the Modified Version, as the publisher.
    4. Preserve all the copyright notices of the Document.
    5. Add an appropriate copyright notice for your modifications adjacent to the other copyright notices.
    6. Include, immediately after the copyright notices, a license notice giving the public permission to use the Modified Version under the terms of this License, in the form shown in the Addendum below.
    7. Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document’s license notice.
    8. Include an unaltered copy of this License.
    9. Preserve the section Entitled “History”, Preserve its Title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page. If there is no section Entitled “History” in the Document, create one stating the title, year, authors, and publisher of the Document as given on its Title Page, then add an item describing the Modified Version as stated in the previous sentence.
    10. Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for previous versions it was based on. These may be placed in the “History” section. You may omit a network location for a work that was published at least four years before the Document itself, or if the original publisher of the version it refers to gives permission.
    11. For any section Entitled “Acknowledgements” or “Dedications”, Preserve the Title of the section, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein.
    12. Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. Section numbers or the equivalent are not considered part of the section titles.
    13. Delete any section Entitled “Endorsements”. Such a section may not be included in the Modified Version.
    14. Do not retitle any existing section to be Entitled “Endorsements” or to conflict in title with any Invariant Section.
    15. Preserve any Warranty Disclaimers.

    If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version’s license notice. These titles must be distinct from any other section titles.

    You may add a section Entitled “Endorsements”, provided it contains nothing but endorsements of your Modified Version by various parties—for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.

    You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.

    The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.

  6. COMBINING DOCUMENTS

    You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.

    The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original 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 “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.”

  7. 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.

  8. 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, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which 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 half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.

  9. 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, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

    If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.

  10. TERMINATION

    You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.

    However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

    Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

    Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.

  11. 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 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. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.

  12. RELICENSING

    “Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.

    “CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.

    “Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.

    An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.

    The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.

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:

  Copyright (C)  year  your name.
  Permission is granted to copy, distribute and/or modify this document
  under the terms of the GNU Free Documentation License, Version 1.3
  or any later version published by the Free Software Foundation;
  with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
  Texts.  A copy of the license is included in the section entitled ``GNU
  Free Documentation License''.

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this:

    with the Invariant Sections being list their titles, with
    the Front-Cover Texts being list, and with the Back-Cover Texts
    being list.

If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

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.