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Free Software Project Management HOWTOBenjamin "Mako" Hill mako@debian.org
1. IntroductionSkimming through freshmeat.net provides mountains of reasons for this HOWTO's existence--the Internet is littered with excellently written and useful programs that have faded away into the universe of free software forgottenness. This dismal scene made me ask myself, "Why?" This HOWTO tries to do a lot of things (probably too many), but it can't answer that question and won't attempt it. What this HOWTO will attempt to do is give your Free Software project a fighting chance--an edge. If you write a piece of crap that no one is interested in, you can read this HOWTO until you can recite it in your sleep and your project will probably fail. Then again, you can write a beautiful, relevant piece of software and follow every instruction in this HOWTO and your software may still not make it. Sometimes life is like that. However, I'll go out a limb and say that if you write a great, relevant pieces of software and ignore the advise in this HOWTO, you'll probably fail more often. A lot of the information in this HOWTO is best called common sense. Of course, as any debate on interfaces will prove, what is common sense to some programmers proves totally unintuitive to others. After explaining bits and pieces of this HOWTO to Free Software developers on several occasions, I realized that writing this HOWTO might provide a useful resource and a forum for programmers to share ideas about what has and has not worked for them. As anyone involved in any of what seems like an unending parade of ridiculous intellectual property clashes will attest to, a little bit of legalese proves important. 1.1. Copyright InformationThis document is copyrighted (c) 2000 Benjamin "Mako" Hill and is distributed under the terms of the GNU Free Documentation License. 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 no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license can be found in Appendix A. 1.2. DisclaimerNo liability for the contents of this documents can be accepted. Use the concepts, examples and other content at your own risk. As this is a new edition of this document, there may be errors and inaccuracies, that may of course be damaging to your project (and potentially your system). Proceed with caution, and although this is highly unlikely, the author(s) does not take any responsibility for that. All copyrights are held by their by their respective owners, unless specifically noted otherwise. Use of a term in this document should not be regarded as affecting the validity of any trademark or service mark. Naming of particular products or brands should not be seen as endorsements. 1.3. New VersionsThis version is the part of the third pre-release cycle of this HOWTO. It is written to be released to developers for critique and brainstorming. Please keep in mind that this version of the HOWTO is still in an infant stage and will continue to be revised extensively. The latest version number of this document should always be listed on the projects homepage hosted by yukidoke.org. The newest version of this HOWTO will always be made available at the same website, in a variety of formats:
1.4. CreditsIn this version I have the pleasure of acknowledging: Fellow Debian developer Martin Michlmayr and Vivek Venugopalan who sent me information and links to extremely interesting articles. I've added both to the bibliography and I've added information from each into the HOWTO. Thanks to Andrew Shugg who pointed out several errors in the document. Also, a big thanks to Sung Wook Her (AKA RedBaron) who is doing the first translation of the HOWTO into Korean. I've been happy to see that people have enjoyed and benefited from the HOWTO so far. Older thanks that I don't want to take out yet include: Josh Crawford, Andy King, and Jaime Davila who all read through this in entirety and gave me feedback that has helped me make changes and improvements to this document. I can't thank you guys enough for your help. An extra "Thank You" goes to Andy King who who read through this several times and submitted patches to make life easier for me. Karl Fogel, the author of Open Source Development with CVS published by the Coriolis Open Press. Large parts of his book are available on the web. 225 pages of the book are available under the GPL and constitute the best tutorial on CVS I've ever seen. The rest of the book covers, "the challenges and philosophical issues inherent in running an Open Source project using CVS." The book does a good job of covering some of the subjects brought up in this HOWTO and much more. The book's website has information on ordering the book and provides several translations of the chapters on CVS. If you are seriously interested in running a Free Software project, you want this book. I tried to mention Fogel in sections of this HOWTO where I knew I was borrowing directly from his ideas. If I missed any, I'm sorry. I'll try and have those fixed in future versions. Karl Fogel can be reached at <kfogel (at) red-bean (dot) com> Also providing support material, and inspiration for this HOWTO is Eric S. Raymond for his prolific, consistent, and carefully crafted arguments and Lawrence Lessig for reminding me of the importance of Free Software. Additionally, I want to thank every user and developer involved with the Debian Project. The project has provided me with a home, a place to practice free software advocacy, a place to make a difference, a place to learn from those who have been involved with the movement much longer than I, and proof of a free software project that definitely, definitely works. Above all, I want to thank Richard Stallman for his work at the Free Software Foundation and for never giving up. Stallman provides and articulates the philosophical basis that attracts me to free software and that drives me toward writing a document to make sure it succeeds. RMS can always be emailed at <rms (at) gnu (dot) org>. 1.5. FeedbackFeedback is always and most certainly welcome for this document. Without your submissions and input, this document wouldn't exist. Do you feel that something is missing? Don't hesitate to contact me to have me write a chapter, section, or subsection or to write one yourself. I want this document to be a product of the Free Software development process that it heralds and I believe that its ultimate success will be rooted in its ability to do this. Please send your additions, comments, and criticisms to the following email address: <mako@debian.org>. 1.6. TranslationsI know that not everyone speaks English. Translations are nice and I'd love for this HOWTO to gain the kind of international reach afforded by translated versions. I've been contacted by a reader who promises a translation into Korean. However, this HOWTO is still young and other than the promise of Korean, English is all that is currently available. If you would like to help with or do a translation, you will gain my utmost respect and admiration and you'll get to be part of a cool process. If you are at all interested, please don't hesitate to contact me at: <mako@debian.org>. 2. Starting a ProjectWith very little argument, the beginning is the most difficult period in a project's life to do successful free software project management. Laying a firm foundation will determine whether your project flourishes or withers away and dies. It is also the subject that is of most immediate interest to anyone reading this document as a tutorial. Starting a project involves a dilemma that you as a developer must try and deal with: no potential user for your program is interested in a program that doesn't work, while the development process that you want to employ holds involvement of users as imperative. It is in these dangerous initial moments that anyone working to start a free software project must try and strike a balance along these lines. One of the most important ways that someone trying to start a project can work toward this balance is by establishing a solid framework for the development process through some of the suggestions mentioned in this section. 2.1. Choosing a ProjectIf you are reading this document, there's a good chance you already have an idea for a project in mind. Chances are also pretty good that it fills a perceived gap by doing something that no other free software project does or by doing something in a way that is unique enough to necessitate a brand new piece of software. 2.1.1. Identify and articulate your ideaEric S. Raymond writes about how free software projects start in his essay, "The Cathedral and the Bazaar," which comes as required reading for any free software developer. It is available online . In "The Cathedral and the Bazaar," Raymond tells us that: "every good work of software starts by scratching a developers itch." Raymond's now widely accepted hypothesis is that new free software programs are written, first and foremost, to solve a specific problem facing the developer. If you have an idea for a program in mind, chances are good that it targets a specific problem or "itch" you want to see scratched. This idea is the project. Articulate it clearly. Write it out. Describe the problem you will attack in detail. The success of your project in tackling a particular problem will be tied to your ability to identify that problem clearly early on. Find out exactly what it is that you want your project to do. Monty Manley articulates the importance of this initial step in an essay, "Managing Projects the Open Source Way." As the next section will show, there is a lot of work that needs to be done before software is even ready to be coded. Manley says, "Beginning an OSS project properly means that a developer must, first and foremost, avoid writing code too soon!" 2.1.2. Evaluate your ideaIn evaluating your idea, you need to first ask yourself a few questions. This should happen before you move any further through this HOWTO. Ask yourself: Is the free software development model really the right one for your project? Obviously, since the program scratches your itch, you are definitely interested in seeing it implemented in code. But, because one hacker coding in solitude fails to qualify as a free software development effort, you need to ask yourself a second question: Is anybody else interested? Sometimes the answer is a simple "no." If you want to write a set of scripts to sort your MP3 collection on your machine, maybe the free software development model is not the best one to choose. However, if you want to write a set of scripts to sort anyone's MP3s, a free software project might fill a useful gap. Luckily, the Internet is a place so big and so diverse that, chances are, there is someone, somewhere, who shares your interests and who feels the same "itch." It is the fact that there are so many people with so many similar needs and desires that introduces the third major question: Has somebody already had your idea or a reasonably similar one? 2.1.2.1. Finding Similar ProjectsThere are places you can go on the web to try and answer the question above. If you have experience with the free software community, you are probably already familiar with many of these sites. All of the resources listed below offer searching of their databases:
2.1.2.2. Deciding to ProceedOnce you have successfully charted the terrain and have an idea about what kinds of similar free software projects exist, every developer needs to decide whether to proceed with their own project. It is rare that a new project seeks to accomplish a goal that is not at all similar or related to the goal of another project. Anyone starting a new project needs to ask themselves: "Will the new project be duplicating work done by another project? Will the new project be competing for developers with an existing project? Can the goals of the new project be accomplished by adding functionality to an existing project?" If the answer to any of these questions is "yes," try to contact the developer of the existing project(s) in question and see if he or she might be willing to collaborate with you. For many developers this may be the single most difficult aspect of free software project management, but it is an essential one. It is easy to become fired up by an idea and get caught up in the momentum and excitement of a new project. It is often extremely difficult to do, but it is important that any free software developer remembers that the best interests of the free software community and the quickest way to accomplish your own project's goals and the goals of similar projects can often be accomplished by not starting a new development effort. 2.2. Naming your projectWhile there are plenty of projects that fail with descriptive names and plenty that succeed without them, I think naming your project is worth giving a bit of thought. Leslie Orchard tackles this issue in an Advogato article. His article is short and definitely worth looking over quickly. The synopsis is that Orchard recommends you pick a name where, after hearing the name, many users or developers will both:
Humorously, Orchard's project, "Iajitsu," does neither. It is probably unrelated that development has effectively frozen since the article was written. He makes a good point though. There are companies whose only job is to make names for pieces of software. They make ridiculous amount of money doing it and are supposedly worth it. While you probably can't afford a company like this, you can afford to learn from their existence and think a little bit about the name you are giving your project because it does matter. If there is a name you really want but it doesn't fit Orchard's criteria, you can still go ahead. I thought "gnubile" was one of the best I'd heard for a free software project ever and I still talk about it long after I've stopped using the program. However, if you can be flexible on the subject, listen to Orchard's advice. It might help you. 2.3. Licensing your SoftwareOn one (somewhat simplistic) level, the difference between a piece of free software and a piece of propriety software is the license. A license helps you as the developer by protecting your legal rights to have your software distributed under your terms and helps demonstrate to those who wish to help you or your project that they are encouraged to join. 2.3.1. Choosing a licenseAny discussion of licenses is also sure to generate at least a small flame war as there are strong feelings that some free software licenses are better than others. This discussion also brings up the question of "Open Source Software" and the debate over the terms "Open Source Software" and "Free Software". However, because I've written the Free Software Project Management HOWTO and not the Open Source Software Project Management HOWTO, my own allegiances in this argument are in the open. In attempting to reach a middle ground through diplomacy without sacrificing my own philosophy, I will recommend picking any license that conforms to the Debian Free Software Guidelines. Originally compiled by the Debian project under Bruce Perens, the DFSG forms the first version of the Open Source Definition. Examples of free licenses given by the DFSG are the GPL, the BSD, and the Artistic License. As ESR mentions in his his HOWTO[ESRHOWTO], don't write your own license if at all possible. The three licenses I mention all have long interpretive traditions. They are also definitely free software (and can therefore be distributed as part of Debian and in other places that permit the transfer of free software). Conforming to the definition of free software offered by Richard Stallman in "The Free Software Definition", any of these licenses will uphold, "users' freedom to run, copy, distribute, study, change and improve the software." There are plenty of other licenses that also conform to the DFSG but sticking with a more well-known license will offer the advantage of immediate recognition and understanding. Many people write three or four sentences in a COPYING file and assume that they have written a free software license--as my long experience with the debian-legal mailing professes, this is very often not the case. In attempting a more in-depth analysis, I agree with Karl Fogel's description of licenses as falling into two groups: those that are the GPL and those that are not the GPL. Personally, I license all my software under the GPL. Created and protected by the Free Software Foundation and the GNU Project, the GPL is the license for the Linux kernel, GNOME, Emacs, and the vast majority of GNU/Linux software. It's the obvious choice but I also believe it is a good one. Any BSD fanatic will urge you to remember that there is a viral aspect to the GPL that prevents the mixture of GPL'ed code with non-GPL'ed code. To many people (myself included), this is a benefit, but to some, it is a major drawback. Many people write three or four sentences in a COPYING file and assume that they have written a free software license--as my long experience with the debian-legal mailing professes, this is very often not the case. It may not protect you, it may not protect your software, and it may make things very difficult for people that want to use your software but who pay a lot of attention to the subtle legal points of licenses. If you are passionate about a home-brewed license, run it by either people at OSI or the debian-legal mailing list first protect yourself from unanticipated side-effects of your license. The three major licenses can be found at the following locations:
In any case, please read through any license before your release your software under it. As the primary developer, you can't afford any license surprises. 2.3.2. The mechanics of licensingThe text of the GPL offers a good description of the mechanics of applying a license to a piece of software. My quick checklist for applying a license includes:
2.3.3. Final license warningPlease, please, please, place your software under some license. It may not seem important, and to you it may not be, but licenses are important. For a piece of software to be included in the Debian GNU/Linux distribution, it must have a license that fits the Debian Free Software Guidelines. If your software has no license, it can not be distributed as a package in Debian until you re-release it under a free license. Please save yourself and others trouble by releasing the first version of your software with a clear license. 2.4. Choosing a Method of Version NumberingThe most important thing about a system of version numbering is that there is one. It may seem pedantic to emphasize this point but you'd be surprised at the number of scripts and small programs that pop up without any version number at all. The second most important thing about a system of numbering is that the numbers always go up. Automatic version tracking systems and people's sense of order in the universe will fall apart if version numbers don't rise. It doesn't really matter if 2.1 is a big jump and 2.0.005 is a small jump but it does matter that 2.1 is more recent than 2.0.005. Follow these two simple rules and you will not go (too) wrong. Beyond this, the most common technique seems to be the "major level," "minor level," "patch level" version numbering scheme. Whether you are familiar with the name or not, you interact with it all the time. The first number is the major number and it signifies major changes or rewrites. The second number is the minor number and it represents added or tweaked functionality on top of a largely coherent structure. The third number is the patch number and it usually will only refer to releases fixing bugs. The widespread use of this scheme is why I know the nature and relative degree in the differences between a 2.4.12 release of the Linux kernel and a 2.4.11, 2.2.12, and 1.2.12 without knowing anything about any of the releases. You can bend or break these rules, and people do. But beware, if you choose to, someone will get annoyed, assume you don't know, and try and educate you, probably not nicely. I always follow this method and I implore you to do so as well. There are several version numbering systems that are well known, useful, and that might be worth looking into before you release your first version.
2.5. DocumentationA huge number of otherwise fantastic free software applications have withered and died because their author was the only person who knew how to use them fully. Even if your program is written primarily for a techno-savvy group of users, documentation is helpful and even necessary for the survival of your project. You will learn later in Section 4.3 that you should always release something that is usable. A piece of software without documentation is not usable. There are lots of different people you should document for and there are lots of ways to document your project. The importance of documentation in source code to help facilitate development by a large community is vital but it falls outside the scope of this HOWTO. This being the case, this section deals with useful tactics for user-directed documentation. A combination of tradition and necessity has resulted in a semi-regular system of documentation in most free software projects that is worth following. Both users and developers expect to be able to get documentation in several ways and it's essential that you provide the information they are seeking in a form they can read if your project is ever going to get off the ground. People have come to expect: 2.5.1. Man pagesYour users will want to be able to type "man yourprojectname" end up with a nicely formatted man page highlighting the basic use of your application. Make sure that before you release your program, you've planned for this. Man pages are not difficult to write. There is excellent documentation on the man page writing process available through the "The Linux Man-Page-HOWTO" which is available through the Linux Documentation project (LDP) and is written by Jens Schweikhardt. It is available from Schweikhardt's site or from the LDP. It is also possible to write man pages using DocBook SGML. Because man pages are so simple and the DocBook method relatively new, I have not been able to follow this up but would love help from anyone who can give me more information on how exactly how this is done. 2.5.2. Command line accessible documentationMost users will expect some basic amount of documentation to be easily available from the command line. For few programs should this type of documentation extend for more than one screen (24 or 25 lines) but it should cover the basic usage, a brief (one or two sentence) description of the program, a list of the commands with explanations, as well as all the major options (also with explanations), plus a pointer to more in-depth documentation for those who need it. The command line documentation for Debian's apt-get serves as an excellent example and a useful model:
It has become a GNU convention to make this type of information accessible with the "-h" and the "--help" options. Most GNU/Linux users will expect to be able to retrieve basic documentation these ways so if you choose to use different methods, be prepared for the flames and fallout that may result. 2.5.3. Files users will expectIn addition to man pages and command-line help, there are certain files where people will look for documentation, especially in any package containing source code. In a source distribution, most of these files can be stored in the root directory of the source distribution or in a subdirectory of the root called "doc" or "Documentation." Common files in these places include:
2.5.4. WebsiteIt's only indirectly an issue of documentation but a good website is quickly becoming an essential part of any free software project. Your website should provide access to your documentation (in HTML if possible). It should also include a section for news and events around your program and a section that details the process of getting involved with development or testing and make an open invitation. It should also supply links to any mailing lists, similar websites, and provide a direct link to all the available ways of downloading your software. 2.5.5. Other documentation hints
2.6. Other Presentation IssuesMany of the remaining issues surrounding the creation of a new free software program fall under what most people describe as common sense issues. Its often said that software engineering is 90 percent common sense combined with 10 percent specialized knowledge. Still, they are worth noting briefly in hopes that they may remind a developer of something they may have forgotten. 2.6.1. Package File NamesI agree with ESR when he says that: " It's helpful to everybody if your archive files all have GNU-like names -- all-lower-case alphanumeric stem prefix, followed by a dash, followed by a version number, extension, and other suffixes." There is more info (including lots of examples of what not to do in his Software Release Practices HOWTO which is included in this HOWTO's bibliography and can be found through the LDP. 2.6.2. Package formatsPackage formats may differ depending on the system you are developing for. For windows based software, Zip archives (.zip) usually serve as the package format of choice. If you are developing for GNU/Linux, *BSD, or any UN*X, make sure that your source code is always available in tar'ed and gzip'ed format (.tar.gz). UNIX compress (.Z) has gone out of style and usefulness and faster computers have brought bzip2 (.bz2) into the spot-light as a more effective compression medium. I now make all my releases available in both gzip'ed and bzip2'ed tarballs. Binary packages should always be distribution specific. If you can build binary packages against a current version of a major distribution, you will only make your users happy. Try to foster relationships with users or developers of large distributions to develop a system for the consistent creation of binary packages. It's often a good idea to provide RedHat RPM's (.rpm), Debian deb's (.deb) and source RPM's SRPM's if possible. Remember: While these binaries packages are nice, getting the source packaged and released should always be your priority. Your users or fellow developers can and will do the the binary packages for you. 2.6.3. Version control systemsA version control system can make a lot of these problems of packaging (and a lot of other problems mentioned in this HOWTO) less problematic. If you are using *NIX, CVS is your best bet. I recommend Karl Fogel's book on the subject (and the posted HTML version) wholeheartedly. CVS or not, you should probably invest some time into learning about a version control system because it provides an automated way of solving many of the problems described by this HOWTO. I am not aware of any free version control systems for Windows or Mac OS but I know that CVS clients exist for both platforms. Websites like SourceForge do a great job as well with a nice, easy-to-use web interface to CVS. I'd love to devote more space in this HOWTO to CVS because I love it (I even use CVS to keep versions straight on this HOWTO!) but I think it falls outside the scope of this document and already has its own HOWTOs. Most notably is the CVS Best Practices HOWTO[CVSBESTPRACTICES] which I've included in the attached bibliography. 2.6.4. Useful tidbits and presentation hintsOther useful hints include:
3. Maintaining a Project: Interacting with DevelopersOnce you have gotten your project started, you have overcome the most difficult hurdles in the development process of your program. Laying a firm foundation is essential, but the development process itself is equally important and provides just as many opportunities for failure. In the next two sections, I will describe running a project by discussing how to maintain a development effort through interactions with developers and with users. In releasing your program, your program becomes free software. This transition is more than just a larger user base. By releasing your program as free software, your software becomes the free software community's software. The direction of your software's development will be reshaped, redirected, and fully determined by your users and, to a larger extent, by other developers in the community. The major difference between free software development and propriety software development is the developer base. As the leader of a free software project, you need to attract and keep developers in a way that leaders of proprietary software projects simply don't have to worry about. As the person leading development of a free software project, you must harness the work of fellow developers by making responsible decisions and by responsibly choosing not to make decisions. You have to direct developers without being overbearing or bossy. You need to strive to earn respect and never forget to give it out. 3.1. Delegating WorkBy now, you've hypothetically followed me through the early programming of a piece of software, the creation of a website and system of documentation, and we've gone ahead and (as will be discussed in Section 4.3) released it to the rest of the world. Times passes, and if things go well, people become interested and want to help. The patches begin flowing in. Like the parent of any child who grows up, it's now time to wince, smile and do most difficult thing in any parents life: It's time to let go. Delegation is the political way of describing this process of "letting go." It is the process of handing some of the responsibility and power over your project to other responsible and involved developers. It is difficult for anyone who has invested a large deal of time and energy into a project but it essential for the growth of any free software project. One person can only do so much. A free software project is nothing without the involvement of a group of developers. A group of developers can only be maintained through respectful and responsible leadership and delegation. As your project progresses, you will notice people who are putting significant amounts of time and effort into your project. These will be the people submitting the most patches, posting most on the mailing lists, and engaging in long email discussions. It is your responsibility to contact these people and to try and shift some of the power and responsibility of your position as the project's maintainer onto them (if they want it). There are several easy ways you can do this: In a bit of a disclaimer, delegation need not mean rule by committee. In many cases it does and this has been proven to work. In other cases this has created problems. Managing Projects the Open Source Way argues that "OSS projects do best when one person is the clear leader of a team and makes the big decisions (design changes, release dates, and so on)." I think this often true but would urge developers to consider the ideas that the project leader need not be the project's founder and that these important powers need not all rest with one person but that a release manager may be different than a lead developer. These situations are tricky politically so be careful and make sure it's necessary before you go around empowering people. 3.1.1. How to delegateYou may find that other developers seem even more experienced or knowledgeable than you. Your job as a maintainer does not mean you have to be the best or the brightest. It means you are responsible for showing good judgment and for recognizing which solutions are maintainable and which are not. Like anything, its easier to watch others delegate than to do it yourself. In a sentence: Keep an eye out for other qualified developers who show an interest and sustained involvement with your project and try and shift responsibility toward them. The following ideas might be good places to start or good sources of inspiration: 3.1.1.1. Allow a larger group of people to have write access to your CVS repository and make real efforts toward rule by a committeeApache is an example of a project that is run by small group of developers who vote on major technical issues and the admission of new members and all have write access to the main source repository. Their process is detailed online. The Debian Project is an extreme example of rule by committee. At current count, more than 700 developers have full responsibility for aspects of the project. All these developers can upload into the main FTP server, and vote on major issues. Direction for the project is determined by the project's social contract and a constitution. To facilitate this system, there are special teams (i.e. the install team, the Japanese language team) as well as a technical committee and a project leader. The leader's main responsibility is to, "appoint delegates or delegate decisions to the Technical Committee." While both of these projects operate on a scale that your project will not (at least initially), their example is helpful. Debian's idea of a project leader who can do nothing but delegate serves as a caricature of how a project can involve and empower a huge number of developers and grow to a huge size. 3.1.1.2. Publicly appoint someone as the release manager for a specific releaseA release manager is usually responsible for coordinating testing, enforcing a code freeze, being responsible for stability and quality control, packaging up the software, and placing it in the appropriate places to be downloaded. This use of the release manager is a good way to give yourself a break and to shift the responsibility for accepting and rejecting patches onto someone else. It is a good way of very clearly defining a chunk of work on the project as belonging to a certain person and its a great way of giving yourself room to breath. 3.1.1.3. Delegate control of an entire branchIf your project chooses to have branches (as described in Section 3.3), it might be a good idea to appoint someone else to be the the head of a branch. If you like focusing your energy on development releases and the implementation of new features, hand total control over the stable releases to a well-suited developer. The author of Linux, Linus Torvalds, came out and crowned Alan Cox as "the man for stable kernels." All patches for stable kernels go to Alan and, if Linus were to be taken away from work on Linux for any reason, Alan Cox would be more than suited to fill his role as the acknowledged heir to the Linux maintainership. 3.2. Accepting and Rejecting PatchesThis HOWTO has already touched on the fact that as the maintainer of a free software project, one of your primary and most important responsibilities will be accepting and rejecting patches submitted to you by other developers. 3.2.1. Encouraging Good PatchingAs the person managing or maintaining the project, you aren't the person who is going to be making a lot of patches. However, it's worth knowing about ESR's section on Good Patching Practice in the Software Release Practices HOWTO[ESRHOWTO]. I don't agree with ESR's claim that most ugly or undocumented patches are probably worth throwing out at first sight--this just hasn't been my experience, especially when dealing with bug fixes that often don't come in the form of patches at all. Of course, this doesn't mean that I like getting poorly done patches. If you get ugly -e patches, if you get totally undocumented patches, and especially if they are anything more than trivial bug-fixes, it might be worth judging the patch by some of the criteria in ESR's HOWTO and then throwing people the link to the document so they can do it the "right way." 3.2.2. Technical judgmentIn Open Source Development with CVS, Karl Fogel makes a convincing argument that the most important things to keep in mind when rejecting or accepting patches are:
These are the criteria that you as a project maintainer should take into account each time you receive a patch. Fogel elaborates on this and states the "the questions to ask yourself when considering whether to implement (or approve) a change are:"
The answers to these questions are never straightforward and its very possible (and even likely) that the person who submitted the patch may feel differently about the answer to these questions than you do. However, if you feel that that the answer to either of those questions is "no," it is your responsibility to reject the change. If you fail to do this, the project will become unwieldy and unmaintainable and many ultimately fail. 3.2.3. Rejecting patchesRejecting patches is probably the most difficult and sensitive job that the maintainer of any free software project has to face. But sometimes it has to be done. I mentioned earlier (in Section 3 and in Section 3.1) that you need to try and balance your responsibility and power to make what you think are the best technical decisions with the fact that you will lose support from other developers if you seem like you are on a power trip or being overly bossy or possessive of the community's project. I recommend that you keep these three major concepts in mind when rejecting patches (or other changes): 3.2.3.1. Bring it to the communityOne of the best ways of justifying a decision to reject a patch and working to not seem like you keep an iron grip on your project is by not making the decision alone at all. It might make sense to turn over larger proposed changes or more difficult decisions to a development mailing list where they can be discussed and debated. There will be some patches (bug fixes, etc.) which will definitely be accepted and some that you feel are so off base that they do not even merit further discussion. It is those that fall into the gray area between these two groups that might merit a quick forward to a mailing list. I recommend this process wholeheartedly. As the project maintainer you are worried about making the best decision for the project, for the project's users and developers, and for yourself as a responsible project leader. Turning things over to an email list will demonstrate your own responsibility and responsive leadership as it tests and serves the interests of your software's community. 3.2.3.2. Technical issues are not always good justificationEspecially toward the beginning of your project's life, you will find that many changes are difficult to implement, introduce new bugs, or have other technical problems. Try to see past these. Especially with added functionality, good ideas do not always come from good programmers. Technical merit is a valid reason to postpone an application of a patch but it is not always a good reason to reject a change outright. Even small changes are worth the effort of working with the developer submitting the patch to iron out bugs and incorporate the change if you think it seems like a good addition to your project. The effort on your part will work to make your project a community project and it will pull a new or less experienced developer into your project and even teach them something that might help them in making their next patch. 3.2.3.3. Common courtesyIt should go without saying but, above all and in all cases, just be nice. If someone has an idea and cares about it enough to write some code and submit a patch, they care, they are motivated, and they are already involved. Your goal as the maintainer is make sure they submit again. They may have thrown you a dud this time but next time may be the idea or feature that revolutionizes your project. It is your responsibility to first justify your choice to not incorporate their change clearly and concisely. Then thank them. Let them know that you a appreciate their help and feel horrible that you can't incorporate their change. Let them know that you look forward to their staying involved and you hope that the next patch or idea meshes better with your project because you appreciate their work and want to see it in your application. If you have ever had a patch rejected after putting a large deal of time, thought, and energy into it, you remember how it feels and it feels bad. Keep this in mind when you have to let someone down. It's never easy but you need to do everything you can to make it as not-unpleasant as possible. 3.3. Stable and Development BranchesThe idea of stable and development branches has already been described briefly in Section 2.4 and in Section 3.1.1.3. These allusions attest to some of the ways that multiple branches can affect your software. Branches can let you avoid (to some extent) some of the problems around rejecting patches (as described in Section 3.2) by allowing you to temporarily compromise the stability of your project without affecting those users who need that stability. The most common way of branching your project is to have one branch that is stable and one that is for development. This is the model followed by the Linux kernel that is described in Section 2.4. In this model, there is always one branch that is stable and always one that is in development. Before any new release, the development branch goes into a "feature freeze" as described in Section 3.4.1 where major changes and added features are rejected or put on hold under the development kernel is released as the new stable branch and major development resumes on the development branch. Bug fixes and small changes that are unlikely to have any large negative repercussions are incorporated into the stable branch as well as the development branch. Linux's model provides an extreme example. On many projects, there is no need to have two versions constantly available. It may make sense to have two versions only near a release. The Debian project has historically made both a stable and an unstable distribution available but has expanded to this to include: stable, unstable, testing, experimental, and (around release time) a frozen distribution that only incorporates bug fixes during the transition from unstable to stable. There are few projects whose size would necessitate a system like Debian's but this use of branches helps demonstrate how they can be used to balance consistent and effective development with the need to make regular and usable releases. In trying to set up a development tree for yourself, there are several things that might be useful to keep in mind:
3.4. Other Project Management issuesThere are more issues surrounding interaction with developers in a free software project that I can not touch on in great detail in a HOWTO of this size and scope. Please don't hesitate to contact me if you see any major omissions. Other smaller issues that are worth mentioning are: 3.4.1. FreezingFor those projects that choose to adopt a split development model (Section 3.3), freezing is a concept that is worth becoming familiar with. Freezes come in two major forms. A "feature freeze" is a period when no significant functionality is added to a program. It is a period where established functionality (even skeletons of barely working functionality) can be improved and perfected. It is a period where bugs are fixed. This type of freeze is usually applied some period (a month or two) before a release. It is easy to push a release back as you wait for "one more feature" and a freeze helps to avoid this situation by drawing the much needed line in the sand. It gives developers room they need to get a program ready for release. The second type of freeze is a "code freeze" which is much more like a released piece of software. Once a piece of software has entered a "code freeze," all changes to the code are discouraged and only changes that fix known bugs are permitted. This type of freeze usually follows a "feature freeze" and directly precedes a release. Most released software is in what could be interpreted as a sort of high level "code freeze." Even if you never choose to appoint a release manager (Section 3.1.1.2), you will have an easier time justifying the rejection or postponement of patches (Section 3.2) before a release with a publicly stated freeze in effect. 3.5. ForksI wasn't sure about how I would deal with forking in this document (or if I would deal with forking at all). A fork is when a group of developers takes code from a free software project and actually starts a brand new free software project with it. The most famous example of a fork was between Emacs and XEmacs. Both emacsen are based on an identical code-base but for technical, political, and philosophical reasons, development was split into two projects which now compete with each other. The short version of the fork section is, don't do them. Forks force developers to choose one project to work with, cause nasty political divisions, and redundancy of work. Luckily, usually the threat of the fork is enough to scare the maintainer or maintainers of a project into changing the way they run their project. In his chapter on "The Open Source Process," Karl Fogel describes how to do a fork if you absolutely must. If you have determined that is absolutely necessary and that the differences between you and the people threatening to fork are absolutely unresolvable, I recommend Fogel's book as a good place to start. 4. Maintaining a Project: Interacting with UsersIf you've worked your way up to here, congratulations, you are nearing the end of this document. This final section describes some of the situations in which you, in your capacity as project maintainer, will be interacting with users. It gives some suggestions on how these situations might be handled effectively. Interacting with users is difficult. In our discussion of interaction with developers, the underlying assumption is that in a free software project, a project maintainer must constantly strive to attract and keep developers who can easily leave at any time. Users in the free software community are different than developers and are also different than users in the world of proprietary software and they should be treated differently than either group. Some ways in which the groups differ significantly follow:
Trying to tackle this unique situation can only be done indirectly. Developers and maintainers need to listen to users and to try and be as responsive as possible. A solid knowledge of the situation recounted above is any free software developer's best tool for shifting his development or leadership style to fit the unique process of free software project management. This chapters will try and introduce some of the more difficult or important points in any projects interactions with users and give some hints on how to tackle these. 4.1. Testing and TestersIn addition to your users being your developers, they are also (and perhaps more commonly) your testers. Before I get flamed, I should rephrase my sentence: some of your users (those who explicitly volunteer) are your testers. It is important that this distinction be made early on because not all of your users want to be testers. Many users want to use stable software and don't care if they don't have the newest, greatest software with the latest, greatest features. These users except a stable, tested piece of software without major or obvious bugs and will be angry if they find themselves testing. This is yet another way in which a split development model (as mentioned in Section 3.3) might come in handy. "Managing Projects the Open Source Way" describes what a good test should look for:
4.1.1. Automated testingFor many programs, many common mistakes can be caught by automated means. Automated tests tend to be pretty good at catching errors that you've run into several times before or the things you just forget. They are not very good at finding errors, even major ones, that are totally unforeseen. CVS comes with a Bourne shell script called sanity.sh that is worth looking at. Debian uses a program called lintian that checks Debian packages for all of the most common errors. While use of these scripts may not be helpful, there is a host of other sanity checking software on the net that may be applicable (feel free to email me any recommendations). None of these will create a bug-free release but they will avoid at least some major oversights. Finally, if your programs become a long term endeavor, you will find that there are certain errors that you tend to make over and over. Start a collection of scripts that check for these errors to help keep them out of future releases. 4.1.2. Testing by testersFor any program that depends on user interactivity, many bugs will only be uncovered through testing by users actually clicking the keys and pressing the mouse buttons. For this you need testers and as many as possible. The most difficult part of testing is finding testers. It's usually a good tactic to post a message to a relevant mailing list or news group announcing a specific proposed release date and outlining the functionality of your program. If you put some time into the announcement, you are sure to get a few responses. The second most difficult part of testing is keeping your testers and keeping them actively involved in the testing process. Fortunately, there are some tried and true tactics that can applied toward this end:
4.2. Setting up Support InfrastructureWhile testing is important, the large part of your interactions and responsibility to your users falls under the category of support. The best way to make sure your users are adequately supported in using your program is to set up a good infrastructure for this purpose so that your developers and users help each other and less of the burden falls on you. This way, people will also get quicker and better responses to their questions. This infrastructure comes in several major forms: 4.2.1. DocumentationIt should not come as any surprise that the key element to any support infrastructure is good documentation. This topic was largely covered in Section 2.5 and will not be repeated here. 4.2.2. Mailing listsAside from documentation, effective mailing lists will be your greatest tool in providing user support. Running a mailing list well is more complicated than installing mailing list software onto a machine. 4.2.2.1. Separate listsA good idea is too separate your user and development mailing lists (perhaps into project-user@host and project-devel@host) and enforce the division. If people post a development question onto -user, politely ask them to repost it onto -devel and vise versa. Subscribe yourself to both groups and encourage all primarily developers to do the same. This system provides so that no one person is stuck doing all of the support work and works so that users learn more about the program, they can help newer users with their questions. 4.2.2.2. Choose mailing list software wellPlease don't make the selection of mailing list software impulsively. Please consider easy accessibility by users without a lot of technical experience so you want to be as easy as possible. Web accessibility to an archive of the list is also important. The two biggest free software mailing list programs are majordomo and GNU Mailman. A long time advocate of majordomo, I would now recommend any project choose GNU Mailman. It fulfills the criteria listed above and makes it easier. It provides a good mailing list program for a free software project maintainer as opposed to a good mailing list application for a mailing list administrator. There are other things you want to take into consideration in setting up your list. If it is possible to gate your mailing lists to Usenet and provide it in digest form as well as making them accessible on the web, you will please some users and work to make the support infrastructure slightly more accessible. 4.2.3. Other support ideasA mailing list and accessible documentation are far from all you can do to set up good user support infrastructure. Be creative. If you stumble across something that works well, email me and I'll include it here. 4.2.3.1. Make your self accessibleYou can not list too few methods to reach you. If you hang out in an IRC channel, don't hesitate to list it in your projects documentation. List email and snailmail addresses, and ways to reach you via ICQ, AIM, or Jabber if they apply. 4.2.3.2. Bug management softwareFor many large software projects, use of bug management software is essential to keep track of which bugs have been fixed, which bugs have not been fixed, and which bugs are being fixed by which people. Debian uses the Debian Bug Tracking System (BTS) although it may not be best choice for every project (it seems to currently be buckling under its own weight) As well as a damn good web browser, the Mozilla project has spawned a sub-project resulting in a bug tracking system called bugzilla which has become extremely possible and which I like a lot. These systems (and others like them) can be unwieldy so developers should be careful to not spend more time on the bug tracking system than on the bugs or the projects themselves. If a project continues to grow, use of a bug tracking system can provide an easy standard avenue for users and testers to report bugs and for developers and maintainers to fix them and track them in an orderly fashion. 4.3. Releasing Your ProgramAs mentioned earlier in the HOWTO, the first rule of releasing is, release something useful. Non-working or not-useful software will not attract anyone to your project. People will be turned off of your project and will be likely to simply gloss over it next time they see a new version announced. Half-working software, if useful, will intrigue people, whet their appetites for versions to come, and encourage them to join the development process. 4.3.1. When to releaseMaking the decision to release your software for the first time is an incredibly important and incredibly stressful decision. But it needs to done. My advice is to try and make something that is complete enough to be usable and incomplete enough to allow for flexibility and room for imagination by your future developers. It's not an easy decision. Ask for help on a local Linux User Group mailing list or from a group of developer friends. One tactic is to first do an "alpha" or "beta" release as described below in Section 4.3.3. However, most of the guidelines described above still apply. When you feel in your gut that it is time and you feel you've weighed the situation well several times, cross your fingers and take the plunge. After you've released for the first time, knowing when to release becomes less stressful, but just as difficult to gauge. I like the criteria offered by Robert Krawitz in his article, "Free Software Project Management" for maintaining a good release cycle. He recommends that you ask yourself, "does this release..."
If the answer is yes to all of these questions, its probably time for a release. If in doubt, remember that asking for advice can't hurt. 4.3.2. How to releaseIf you've followed the guidelines described in this HOWTO up until this point, the mechanics of doing a release are going to be the easy part of releasing. If you have set up consistent distribution locations and the other infrastructure described in the preceding sections, releasing should be as simple as building the package, checking it once over, and uploading it into the appropriate place and then making your website reflect the change. 4.3.3. Alpha, beta, and development releasesWhen contemplating releases, it worth considering the fact that not every release needs to be a full numbered release. Software users are accustomed to pre-releases but you must be careful to label these releases accurately or they will cause more problems then they are worth. The observation is often made that many free software developers seem to be confused about the release cycle. "Managing Projects the Open Source Way" suggests that you memorize the phrase, "Alpha is not Beta. Beta is not Release" and I'd agree that tis is a probably a good idea.
4.4. Announcing Your ProjectWell, you've done it. You've (at least for the purposes of this HOWTO) designed, built, and released your free software project. All that is left is for you to tell the world so they know to come and try it out and hopefully jump on board with development. If everything is in order as described above, this will be a quick and painless process. A quick announcement is all that it takes to put yourself on the free software community's radar screen. 4.4.1. Mailing lists and UsenetAnnounce your software on Usenet's comp.os.linux.announce. If you only announce your software in two places, have it be c.o.l.a and freshmeat. However, email is still the way that most people on the Internet get their information. Its a good idea to send a message announcing your program to any relevant mailing list you know of and any other relevant Usenet discussion groups. Karl Fogel recommends that use you simple subject describing the fact that the message is an announcement, the name of the program, the version, and a half-line long description of its functionality. This way, any interested user or developer will be immediately attracted to your announcement. Fogel's example looks like:
The rest of the email should describe the programs functionality quickly and concisely in no more than two paragraphs and should provide links to the projects webpage and direct links to downloads for those that want to try it right away. This form will work for both Usenet and mailing list posts. You should repeat this announcement process consistently in the same locations for each subsequent release. 4.4.2. freshmeat.netMentioned earlier in Section 2.1.2.1, in today's free software community, announcements of your project on freshmeat are almost more important than announcements on mailing lists. Visit the freshmeat.net website or their submit project page to post your project onto their site and into their database. In addition to a large website, freshmeat provides a daily newsletter that highlights all the days releases and reaches a huge audience (I personally skim it every night for any interesting new releases). 4.4.3. Project Mailing ListIf you've gone ahead and created mailing lists for your project, you should always announce new versions on these lists. I've found that for many projects, users request a very low-volume announce only mailing list to be notified when new versions are released. freshmeat.net now allows users to subscribe to a particular project so they receive emails every time a new version is announced through their system. It's free and it can stand in for an announce-only mailing list. In my opinion, it can't hurt. BibliographyPrinted BooksKarl Fogel, Open Source Development with CVS, Coriolois Open Press, 1999, 1-57610-490-7. Fogel's "guide to using CVS in the free software world" is much more than its subtitle. In the publisher's own words: "Open Source Development with CVS is one of the first books available that teaches you development and implementation of Open Source software." It also includes the best reference and tutorial to CVS I have ever seen. It is the book that was so good that it prompted me to write this HOWTO because I thought the role it tried to serve was so important and useful. Please check it or buy it if you can and are seriously interested in running a free software project. Lawrence Lessig, Code and Other Laws of Cyberspace, Basic Books, 2000, 0-465-03913-8. While it only briefly talks about free software (and does it by tiptoeing around the free software/open source issue with the spineless use of the term "open code" that only a lawyer could coin), Lessig's book is brilliant. Written by a lawyer, it talks about how regulation on the Internet is not done with law, but with the code itself and how the nature of the code will determine the nature of future freedoms. In addition to being a quick and enjoyable read, it gives some cool history and describes how we need free software in a way more powerfully than anything I've read outside of RMS's "Right to Read." Eric Raymond, The Cathedral and the Bazaar: Musings on Linux and Open Source by an Accidental Revolutionary, O'Reilly, 1999, 1-56592-724-9. Although I have to honestly say that I am not the ESR fan that I used to be, this book proved invaluable in getting me where I am today. The essay that gives the book its title does a good job of sketching the free software process and does an an amazing job of making an argument for free software/open source development as a road to better software. The rest of the book has other of ESR's articles, which for the most part are posted on his website. Still, it's nice thing to own in hard copy and something that every free software/open source hacker should read. Web-Accessible ResourcesGeorge N Dafermos, Management and Virtual Decentralized Networks: The Linux Project. Since the paper includes its own abstract, I thought I would include it here verbatim: This paper was referred to me in my capacity as author of this HOWTO and I was very impressed. It's written by a graduate student in management and I think it succeeds at evaluating the Linux project as an example of a new paradigm in management--one that you will be be placing yourself at the center of in your capacity as maintainer of a free software project. As a developer trying to control an application and guide it to success in the free software world, I'm not sure how useful Dafermos's argument is. It does however, provide a theoretical justification for my HOWTO--free software project management is a different creature than proprietary software project management. If you are interested in the conceptual and theoretical ways that free software project management differs from other types of management, this is a great paper to read. If this paper answers questions of "how?", Dafermos answers the (more difficult to defend) questions of "why?" and does a very good job. Richard Gabriel, The Rise of "Worse is Better". A well written article although I think the title may have confused as many people as the rest of the essay helped. It offers a good description of how to design programs that will succeed and stay maintainable as they grow. Montey Manley, Managing Projects the Open Source Way, Linux Programming, Oct 31, 2000. In one of the better articles on the subject that I've read, Monty sums up some of the major points I touch on including: starting a project, testing, documentation, organizing a team and leadership, and several other topics. While more opinionated that I try to be, I think its an important article that I found very helpful in writing this HOWTO. I've tried to cite him in the places where I borrowed from him most. I have problems much of this piece and I recommend you read [KRAWITZ] at the same time you read Monty's article for a good critique. Eric Steven Raymond, Software Release Practice HOWTO. At first glance, ESR's release practice HOWTO seems to share a lot of terrain with this document. Upon closer examination, the differences become apparent but they are closely related. His document, read in conjunction with mine, will give a reader a good picture of how to go about managing a project. ESR's HOWTO goes into a bit more detail on how to write and what languages to write in. He tends to give more specific instructions and checklists ("name this file this, not this") while this HOWTO speaks more conceptually. There are several sections that are extremely similar. It's also much shorter. My favorite quote from his HOWTO is: ""Managing a project well when all the participants are volunteers presents some unique challenges. This is too large a topic to cover in a HOWTO." Oh really? Perhaps I just do a poor job. Vivek Venugopalan, CVS Best Practices. Venugopalan provides one of the best essays on effective use of CVS that I've come across. It is written for people who already have a good knowledge of CVS. In the chapter on branching, he describes when and how to branch but gives no information on what CVS commands you should use to do this. This is fine (technical CVS HOWTO have been written) but CVS newbies will want to spend some time with Fogel's reference before they will find this one very useful. Venugopalan creates checklists of things to do before, after, and around releases. It's definitely worth a read through as most of his ideas will save tons of developer head aches over any longer period of time. Advogato ArticlesStephen Hindle, 'Best Practices' for Open Source?, Advogato, March 21, 2001. Touching mostly on programming practice (as most articles on the subject usually do), the article talks a little about project management ("Use it!") and a bit about communication within a free software project. Bram Cohen, http://www.advogato.org/article/258.htmlHow to Write Maintainable Code, Advogato, March 15, 2001. This article touches upon the "writing maintainable code" discussion that I try hard to avoid in my HOWTO. It's one of the better (and most diplomatic) articles on the subject that I've found. Robert Krawitz, Free Source Project Management, Advogato, November 4, 2000. This article made me happy because it challenged many of the problems that I had with Monty's article on LinuxProgramming. The author argues that Monty calls simply for the application of old (proprietary software) project management techniques in free software projects instead of working to come up with something new. I found his article to be extremely well thought out and I think it's an essential read for any free software project manager. Lalo Martins, Ask the Advogatos: why do Free Software projects fail?, Advogato, July 20, 2000. While the article is little more than a question, reading the answers to this question offered by Advogato's readers can help. In a lot of ways, this HOWTO acts as my answer to the questions posed in this article but there are others, many of which might take issue with whats is in this HOWTO. It's worth checking out. David Burley, In-Roads to Free Software Development, Advogato, June 14, 2000. This document was written as a response to another Advogato article. Although not about running a project, this describes some of the ways that you can get started with free software development without starting a project. I think this is an important article. If you are interested in becoming involved with free software, this article showcases some of the ways that you can do this without actually starting a project (something that I hope this HOWTO has demonstrated is not to be taken lightly). Jacob Moorman, Importance of Non-Developer Supporters in Free Software, , Advogato, April 16, 2000. Moorman's is a short article but it brings up some good points. The comment reminding developers to thank their testers and end-users is invaluable and oft-forgotten. Leslie Orchard, On Naming an Open Source Project, Advogato, April 12, 2000. I didn't even have a section on project naming in this HOWTO (See Section 2.2) until Leslie Orchard's article reminded me of it. Thanks to Leslie for writing this article! David Allen, Version Numbering Madness, Advogato, February 28, 2000. In this article, David Allen challenges the whole "Major.Minor.Patch" version numbering scheme. Its good to read this as you read Section 2.4. I liked the article and it describes some of the projects that I bring up in my discussion of version numbering. A. GNU Free Documentation LicenseA.1. 0. PREAMBLEThe purpose of this License is to make a manual, textbook, or other written 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 non-commercially. 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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. A.10. 9. TERMINATIONYou 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. A.11. 10. FUTURE REVISIONS OF THIS LICENSEThe 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. |