\input texinfo @c -*-texinfo-*- @c %**start of header (This is for running Texinfo on a region.) @setfilename using-git.info @settitle Workflow in the @command{gawk} project @c %**end of header (This is for running Texinfo on a region.) @dircategory Network applications @direntry * Gawkworkflow: (using-git). Workflow in the `gawk' project. @end direntry @iftex @set DOCUMENT book @set CHAPTER chapter @set SECTION section @set DARKCORNER @inmargin{@image{lflashlight,1cm}, @image{rflashlight,1cm}} @end iftex @ifinfo @set DOCUMENT Info file @set CHAPTER major node @set SECTION node @set DARKCORNER (d.c.) @end ifinfo @ifhtml @set DOCUMENT web page @set CHAPTER chapter @set SECTION section @set DARKCORNER (d.c.) @end ifhtml @set FN file name @set FFN File Name @c merge the function and variable indexes into the concept index @ifinfo @synindex fn cp @synindex vr cp @end ifinfo @iftex @syncodeindex fn cp @syncodeindex vr cp @end iftex @c If "finalout" is commented out, the printed output will show @c black boxes that mark lines that are too long. Thus, it is @c unwise to comment it out when running a master in case there are @c overfulls which are deemed okay. @iftex @finalout @end iftex @smallbook @set TITLE Workflow in the @command{gawk} project @set EDITION 0.0 @set UPDATE-MONTH August, 2014 @c gawk versions: @set VERSION 4.1 @set PATCHLEVEL 0 @copying This is Edition @value{EDITION} of @cite{@value{TITLE}}, for the @value{VERSION}.@value{PATCHLEVEL} (or later) version of the GNU implementation of AWK. @sp 2 Copyright (C) 2014, 2015 Free Software Foundation, Inc. @sp 2 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 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''. @enumerate a @item The FSF's Back-Cover Text is: ``You have the freedom to copy and modify this GNU manual.'' @end enumerate @end copying @ifinfo This file documents the workflow of the developers in the GNU @command{awk} project. @insertcopying @end ifinfo @setchapternewpage odd @titlepage @title @value{TITLE} @subtitle Edition @value{EDITION} @subtitle @value{UPDATE-MONTH} @author J@"urgen Kahrs @author with Arnold D. Robbins @c Include the Distribution inside the titlepage environment so @c that headings are turned off. Headings on and off do not work. @page @vskip 0pt plus 1filll @sp 2 Published by: @sp 1 Free Software Foundation @* 51 Franklin Street, Fifth Floor @* Boston, MA 02110-1301 USA @* Phone: +1-617-542-5942 @* Fax: +1-617-542-2652 @* Email: @email{gnu@@gnu.org} @* URL: @uref{http://www.gnu.org/} @* ISBN 1-882114-93-0 @* @insertcopying @c @sp 2 @c Cover art by ?????. @end titlepage @iftex @headings off @evenheading @thispage@ @ @ @strong{@value{TITLE}} @| @| @oddheading @| @| @strong{@thischapter}@ @ @ @thispage @end iftex @ifnottex @node Top @top Introduction @comment node-name, next, previous, up This file documents the workflow of the developers in the GNU Awk (@command{gawk}) version 4.1 and later. @insertcopying @end ifnottex @menu * Introduction:: About networking. * Basics of GIT repositories:: The fundamental environment of the developer. * Conventions used in the repository:: How to behave. * Tutorial for a first-time-gawk-contributor:: How to get started with least pain. * FAQs and HOWTOs:: General recipes for daily work. * Links:: Where to find the stuff mentioned in this document. * GNU Free Documentation License:: The license for this document. * Index:: The index. @detailmenu * Quick Start:: * Setting up a proper @command{git} repository:: * Pulling the latest changes from the remote repository:: * Checking out a feature branch from the remote repository:: * Semantics of Cloning:: What to consider before you clone. * Local versus Remote:: Where my source code really is. * Tracking and Merging:: What the others are doing. * master:: * stable:: * feature:: * who does what:: * step-by-step instructions for a first-time-gawk-contributor:: * step-by-step instructions for a first-time-gawk-administrator:: * general recipes for daily work:: * references and URLs to books and other texts:: @end detailmenu @end menu @contents @node Introduction @chapter Introduction This @value{DOCUMENT} is meant to be a description of the working habits that were established for collaboration in the GNU Awk project. Such stuff tends to become rather dry, and to prevent you from getting bored at this early stage, we will begin this @value{CHAPTER} with a brief introduction that shows you how to get the source code of the GNU Awk project compiled on your machine. We do this in order to get you motivated to follow us through the later steps that consist mainly of conceptual considerations. We hope that (in later, more abstract steps) you will always remember this down-to-earth introduction, should you ever wonder what all the later bizarre trickery is good for. @menu * Quick Start:: * Setting up a proper @command{git} repository:: * Pulling the latest changes from the remote repository:: * Checking out a feature branch from the remote repository:: @end menu @node Quick Start @section Quick Start: Compiling @command{gawk} in 5 Minutes The following steps will look familiar to you; they are not that much different from the steps you used in the old days when you downloaded a tar ball, extracted it and compiled the source code. It is mainly the very first step that looks different; instead of downloading the tar ball you need the tool @command{git}.@footnote{If the command @command{git} does not exist on your machine, you need adminstrator privileges to install it. By convention, the command is usually part of an installation package by the same name.} @example git clone git://git.savannah.gnu.org/gawk.git cd gawk git checkout gawk-4.1-stable ./bootstrap.sh ./configure make ./gawk --version @end example There are two differences to your working habits. In the third step,, you have to extract (or @dfn{check out}) the @code{gawk-4.1-stable} branch of the current source code (there are other branches available, that's the point where things get interesting). In the fourth step, you must run the @command{bootstrap.sh} script in order to set correctly timestamps on various files. Doing this is essential; it allows you to avoid having to install the correct versions of the various autotools as used by the @command{gawk} maintainer. Isn't this simple? No, it's not that simple. If you plan to go any further (for example compile the source code again next week, including next week's latest update), you will need to know what's going on when you use this seemingly simple @command{git} command (and that's the point where things get bizarre). In the next @value{CHAPTER} you will find a more thorough conceptual explanation, here we are satisfied with getting to know the practical steps necessary to get a working environment going that you can use in your daily work in a reliable way. @node Setting up a proper @command{git} repository @section Setting up a proper @command{git} repository After the initial @emph{checkout} you have access to all the source code files that the maintainers have pushed through the official release procedure. You may not have noticed, but each change is well documented and traceable. This process of tracing the change history is so precise, reproducable and fine-grained that any dubious change may be kicked out later and the author of dubious stuff identified by name and change date. Some bookkeeping is necessary for this and that's why you need @command{git}. @command{git} does all this for you. Developers who have used @command{svn} or @command{cvs} in the past will not be surprised to hear that each change is traceable precisely (they know that @command{svn} and @command{cvs} can do this, too). But the first-time user of @command{git} (as well as the @command{svn} user) may still have failed to notice what he actually did earlier in this @value{CHAPTER}. It is not just a mere copy of the source code that you created, it is a full copy of the entire @dfn{upstream} repository server that you created (or @dfn{cloned}). This means that others could make their own copy of @emph{your} repository and treat it as @emph{their upstream} repository. This is the essential difference between working with @command{svn} and working with @command{git}: by @emph{cloning} you become a repository administrator, whether you like it or not. As such you have some duties that go beyond the duties of an @command{svn} user. For example, you have to identify yourself properly as the owner of the repository by setting some global variables identifying you. The global settings will be used every time you connect again to the upstream repository. @smallexample git config --global user.name "@var{First-Name Last-Name}" git config --global user.email @var{email@@address.site} git config --global color.ui auto @end smallexample You may leave these variables unset, but then you are reduced to an anonymous consumer-only behaviour whenever you connect to the upstream repository. Later you will learn that there are many other variables to be set, most of them serving as defaults that can be overridden if you like. Choosing to work with defaults makes work quick and easy for the most frequent use cases, but that comes at a cost: With so many helpful defaults you may be overwhelmed by the detail and complexity of the real inner working. Here is an example of one of the author's configuration variables: @smallexample $ @kbd{git config --list} @print{} user.name=First-Name Last-Name @print{} user.email=email@@address.site @print{} color.diff=auto @print{} color.status=auto @print{} color.branch=auto @print{} gui.spellingdictionary=en_US @print{} core.repositoryformatversion=0 @print{} core.filemode=true @print{} core.logallrefupdaIsn't this simple? No, it's not that simple. tes=true @print{} remote.origin.fetch=+refs/heads/*:refs/remotes/origin/* @print{} remote.origin.url=ssh://jkahrs@@git.sv.gnu.org/srv/git/gawk.git @print{} branch.master.remote=origin @print{} branch.master.merge=refs/heads/master @print{} branch.xgawk_load.remote=origin @print{} branch.xgawk_load.merge=refs/heads/xgawk_load @end smallexample Changing these variables with specialized variants of the @command{git} command may seem awkward to you and perhaps you prefer to use your favourite text editor to overview and change the variables. That's easy: edit the file @file{.git/config}. @smallexample $ @kbd{cat .git/config} @print{} [core] @print{} repositoryformatversion = 0 @print{} filemode = true @print{} bare = false @print{} logallrefupdates = true @print{} [remote "origin"] @print{} fetch = +refs/heads/*:refs/remotes/origin/* @print{} url = ssh://jkahrs@@git.sv.gnu.org/srv/git/gawk.git @print{} [branch "master"] @print{} remote = origin @print{} merge = refs/heads/master @print{} [branch "cmake"] @print{} remote = origin @print{} merge = refs/heads/cmake @end smallexample Now you can see how variables are structured group-wise. But wait, where is the e-mail address in this list of variables? It is missing in the file @file{.git/config} because that file contains only the local settings of this one repository (while there may be others on your machine). The e-mail address is a variable of a more general kind that should be stored above all the repositories. These are referred to as the @dfn{global} variables: @smallexample $ @kbd{git config --list --global} @print{} user.name=First-Name Last-Name @print{} user.email=email@@address.site @print{} color.diff=auto @print{} color.status=auto @print{} color.branch=auto @print{} gui.spellingdictionary=en_US @end smallexample If you wonder whether there is a parameter @command{--local} to list the local variables, then you should look into the well-structured man pages of @command{git}. The level of detail may overwhelm you, but one day you might appreciate it. @smallexample git help config @end smallexample @node Pulling the latest changes from the remote repository @section Pulling the latest changes from the remote repository Whether you set any of these variables or not, sooner or later you will want to catch up with the changes that happened in the upstream repository. So, how can you update your copy of the repository and re-build the source code? The easiest way is to rely on defaults and use the @emph{pull} command to request updates from the upstream repository: @smallexample git pull ./bootstrap.sh ./configure make @end smallexample When using the @emph{pull} command, all the changes available in all branches of the upstream repository will be copied (and merged) into your local repository. We assume here that we still have the @emph{gawk-4.1-stable} branch checked out (as described earlier) and we are not interested in changes to other existing branches. The merging of changes will be done inside the branches only, so that changes in one branch are kept inside this branch and don't mix up other branches. @c ======================================== But @emph{what is a branch?} you may wonder. It is the name given to a sequence of changes that were made to the master branch outside the master branch. It is easy to look up all the available branches (the names of the change sequences) in the remote upstream repository. @smallexample $ @kbd{git branch -a} @print{} * master @print{} remotes/origin/cmake @end smallexample The asterisk in front of the branch name assures you of the fact that you see the source files as they are in the @emph{master} branch. @node Checking out a feature branch from the remote repository @section Checking out a feature branch from the remote repository It is also easy to have a look at other branches, for example when you are interested in what is going on in a certain @emph{feature branch} that the maintainer set up recently for a new feature to be developed separately (so that others can go on undisturbed). @smallexample $ @kbd{git checkout origin/cmake} $ @kbd{git branch -a} @print{} master @print{} * remotes/origin/cmake $ @kbd{./bootstrap.sh} $ @kbd{./configure} $ @kbd{make} @end smallexample When you try this, take care that you have not changed anything in any source file. @command{git} would notice changes and refuse to checkout the other branch. This is meant to protect you from losing any local changes that you forgot to save. Any source file that is part of the repository and gets generated during the build in a slightly different way than the original would cause such a problem. @smallexample $ @kbd{git status} @print{} # On branch master @print{} # Changes not staged for commit: @print{} # awkgram.c @end smallexample Here we have @file{awkgram.c} that was generated from @file{awkgram.y}. But what was generated differently in the file? @smallexample git diff awkgram.c @end smallexample Ok, you are not interested in textual changes to the copyright notice that are only due to a new calendar year. You are also not interested in the internals of the generated parser and only wonder @emph{How do we get back the original file from the repository?} @smallexample $ @kbd{git checkout awkgram.c} $ @kbd{git diff awkgram.c | wc -l} @print{} 0 @end smallexample After checking the file out once more, there is obviously no difference to the copy saved in the repository. But let's not get distracted, we wanted to find out what was going on in this feature branch. We can find out by asking @command{git} what has changed in the file @file{ChangeLog} of this feature branch relative to the master branch. @smallexample git diff origin/master ChangeLog @end smallexample @noindent This produces: @smallexample diff --git a/ChangeLog b/ChangeLog index eab657c..a499ec5 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,81 +1,3 @@ -2014-09-07 Arnold D. Robbins - - * awk.h: Move libsigsegv stuff to ... - * main.c: here. Thanks to Yehezkel Bernat for motivating - the cleanup. - * symbol.c (make_symbol, install, install_symbol): Add const to - first parameter. Adjust decls and fix up uses. @end smallexample Looks like a minor cleanup operation in the master branch that has not yet been merged into the feature branch. We still don't know what is new in this feature branch, how can we know? By looking at all changes that exist. @smallexample $ @kbd{git diff origin/master --numstat} @print{} 0 78 ChangeLog @print{} 8 3 README_d/README.cmake @end smallexample On your screen you see a list of all differences between the currently checked-out branch and the master branch. It tells you the names of the files that have changed, along with the number of added and deleted lines. Now we can have a closer look at who changed what. Let's single out one particular file that looks interesting. As usual there is a @command{diff} sub-command to list all the changed lines, but there is also a @command{blame} sub-command that tells you who made the last change to any of the lines. @smallexample git blame README_d/README.cmake @end smallexample @noindent This produces (in part): @smallexample 2092a35f (Juergen Kahrs 2014-08-12 17:11:20 +0200 1) CMake is a build automation system 2092a35f (Juergen Kahrs 2014-08-12 17:11:20 +0200 2) http://en.wikipedia.org/wiki/Cmake 2092a35f (Juergen Kahrs 2014-08-12 17:11:20 +0200 3) 2092a35f (Juergen Kahrs 2014-08-12 17:11:20 +0200 4) We try to use it as a replacement for the established GNU build system. 2092a35f (Juergen Kahrs 2014-08-12 17:11:20 +0200 5) This attempt is currently only experimental. If you wonder why anyone 2092a35f (Juergen Kahrs 2014-08-12 17:11:20 +0200 6) should do this, read @end smallexample The strange number on the left margin is the short form of a numerical identifier of the change set. At the moment you can safely ignore it, but this number is the key you need in case you should ever want to cherry-pick some change sets. But cherry-picking is still far away, before you can do this, you have to learn how to make changes to your local repository and @command{push} them to the upstream repository. Some conceptual basics are needed for understanding this essential part of the workflow. @node Basics of GIT repositories @chapter Basics of GIT repositories @menu * Semantics of Cloning:: What to consider before you clone. * Local versus Remote:: Where my source code really is. * Tracking and Merging:: What the others are doing. @end menu @c http://iverilog.wikia.com/wiki/Installation_Guide @c http://www.linuxjournal.com/article/2840 @c http://git-scm.com/book/en/Git-Branching-Branching-Workflows @c https://www.atlassian.com/en/git/workflows @c https://help.github.com/articles/what-is-a-good-git-workflow @c https://guides.github.com/introduction/flow/index.html @c http://supercollider.sourceforge.net/wiki/index.php/Developer_cheatsheet_for_git @c http://savannah.gnu.org/maintenance/UsingGit/ @c http://www.emacswiki.org/emacs/GitForEmacsDevs What is tracking ? @display - How can I use git to contribute source code ? You need an account at Savannah. Read this to understand the first steps: http://savannah.gnu.org/maintenance/UsingGit README.git Use your account there to register your public ssh key at Savannah. Then you are ready to checkout. Remember that (when cloning) you are setting up your own local repository and make sure you configure it properly. git clone ssh://my_account_name@@git.sv.gnu.org/srv/git/gawk.git @end display @node Semantics of Cloning @section Semantics of Cloning @node Local versus Remote @section Local versus Remote @node Tracking and Merging @section Tracking and Merging @node Conventions used in the repository @chapter Conventions used in the repository @menu * master:: * stable:: * feature:: * who does what:: @end menu @node master @section master @node stable @section stable @node feature @section feature @node who does what @section who does what @node Tutorial for a first-time-gawk-contributor @chapter Tutorial for a first-time-gawk-contributor @menu * step-by-step instructions for a first-time-gawk-contributor:: * step-by-step instructions for a first-time-gawk-administrator:: @end menu @node step-by-step instructions for a first-time-gawk-contributor @section step-by-step instructions for a first-time-gawk-contributor @node step-by-step instructions for a first-time-gawk-administrator @section step-by-step instructions for a first-time-gawk-administrator @c e-mail from Arnold 2014-08.24 @c Thanks to Michal for pointing us in the right direction! @c I see this: @c @c bash-4.2$ git config --get push.default @c simple @c @c What does yours say? @c @c It appears that "simple" will be the default in version 2.0: @c @c From: @c http://blog.nicoschuele.com/posts/git-2-0-changes-push-default-to-simple @c @c Matching @c @c The 'matching' option is the default behavior in Git 1.x. It means that if you do a git push without specifying a branch, it will push all your local branches to their matching ones on your remote repository. @c @c Simple @c @c The new default in Git 2.x is 'simple'. It means that when doing a git push without specifying a branch, only your current branch will be pushed to the one git pull would normally get your code from." @c @c So this must explain it. I'll bet yours is set to "matching". I have no @c idea how mine got set to "simple", since I don't recall doing that. @c @c In the future, I will simply make sure to push before switching branches. @c I think I actually prefer that behavior, since it's more intuitive to me. @node FAQs and HOWTOs @chapter FAQs and HOWTOs @menu * general recipes for daily work:: @end menu @node general recipes for daily work @section general recipes for daily work @node Links @chapter Links @menu * references and URLs to books and other texts:: @end menu @node references and URLs to books and other texts @section references and URLs to books and other texts @c The GNU Free Documentation License. @node GNU Free Documentation License @unnumbered GNU Free Documentation License @cindex FDL (Free Documentation License) @cindex Free Documentation License (FDL) @cindex GNU Free Documentation License @center Version 1.3, 3 November 2008 @c This file is intended to be included within another document, @c hence no sectioning command or @node. @display Copyright @copyright{} 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. @uref{http://fsf.org/} 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 functional and useful 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. 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You may use the same title as a previous version if the original publisher of that version gives permission. @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 fewer than five), unless they release you from this requirement. @item State on the Title page the name of the publisher of the Modified Version, as the publisher. @item Preserve all the copyright notices of the Document. @item Add an appropriate copyright notice for your modifications adjacent to the other copyright notices. @item 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. @item Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document's license notice. @item Include an unaltered copy of this License. @item 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. @item 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. @item 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. @item 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. @item Delete any section Entitled ``Endorsements''. Such a section may not be included in the Modified Version. @item Do not retitle any existing section to be Entitled ``Endorsements'' or to conflict in title with any Invariant Section. @item Preserve any Warranty Disclaimers. @end enumerate 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. @item 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.'' @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, 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. @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, 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. @item 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. @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. 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. @item 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. @end enumerate @c fakenode --- for prepinfo @unnumberedsec 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 1.3 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''. @end group @end smallexample If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the ``with@dots{}Texts.'' line with this: @smallexample @group 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}. @end group @end smallexample 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. @c Local Variables: @c ispell-local-pdict: "ispell-dict" @c End: @node Index @comment node-name, next, previous, up @unnumbered Index @printindex cp @bye Conventions: 1. Functions, built-in or otherwise, do NOT have () after them. 2. Gawk built-in vars and functions are in @code. Also program vars and functions. 3. HTTP method names are in @code. 4. Protocols such as echo, ftp, etc are in @samp. 5. URLs are in @url. 6. All RFCs in the index. Put a space between `RFC' and the number.