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Copyright issues

Using material written by others
Your copyright and the PDL

Many people find legal issues boring, but this is an important section. Please read it thoroughly.

Using material written by others

As we write our manuals, we can consult all kinds of other documentation – and so we should, because we want to achieve the best possible result. Any information we find in publicly available third-party manuals, user's guides, tutorials etc. can be freely used in our own docs, but it is important not to confuse information with literal text. We cannot copy-and-paste text from other works into our own documentation, unless the author explicitly permits us to do so.

If you would like to use a piece of text written by somebody else, check the copyright notice of the work in question. If there isn't one, the work is automatically copyrighted under the Berne convention and you must assume that it's illegal to copy it – even partially. This is also true if the work is freely available! Not having to pay for a document does not imply that you can freely copy portions of text and republish them in a work of your own.

Borland InterBase manuals

The Borland InterBase 6 beta docs – although free – are not part of the InterBase package that was open-sourced in July 2000. We have asked Borland several times if we could use these docs “as if they fell under the InterBase Public License”, but they didn't even bother to answer. So feel free to use this documentation set as a source of information, but don't copy text from it.

PostgreSQL docs

PostgreSQL is another major open source database, with (not surprisingly) many similarities to Firebird, but also many differences. Depending on the kind of documentation you are going to write, it may be beneficial to base it on existing PostgreSQL docs. Be aware though that if you use PostgreSQL material, you MUST include their copyright notice in your document!

The PostgreSQL documentation homepage is here:

The most recent PostgreSQL license is currently at:

One nice thing about the PostgreSQL docs is that they are authored in DocBook, just like ours. However, they use DocBook SGML instead of XML, so some tweaking may be necessary. The DocBook SGML sources can be found here:

Or check out the entire CVS tree, docs and all. For instructions, go to:

Your copyright and the PDL

If you contribute to the Firebird documention subproject, your work will be included in the Open Source repository at SourceForge. In January 2005, the Firebird doc team decided to release the documentation it develops under the Public Documentation License. Licensing your work under the PDL means that you retain the copyright, but you grant others certain rights:

  • Free use: everyone may use and distribute your work, for free or for money, as long as the license notice is kept intact.

  • Right to modify: everyone may modify and redistribute your work, as long as any modified versions are PDL-licensed too, the original license notice is kept intact, and the modifications are documented.

  • Larger works: everyone may incorporate your documentation (modified or not) in a larger work. The larger work as a whole need not be released under the PDL, but the license requirements must be fulfilled for the PDL-licensed parts.

What's so nice about the PDL is that it provides the same rights and restrictions on the usage of our docs as the IPL and IDPL (Firebird's code licences) do for the Firebird source code. For the complete license text, see the links in the License Notice below; the DocBook source is in src/docs/firebirddocs/licenses.xml

How to apply the PDL to your work

In order to release your work under the PDL, add an appendix titled License Notice, with this text:

The contents of this Documentation are subject to the Public Documentation License Version 1.0 (the “License”); you may only use this Documentation if you comply with the terms of this License. Copies of the License are available at (PDF) and (HTML).

The Original Documentation is _TITLE OF THE WORK_.

The Initial Writer of the Original Documentation is _INITIAL AUTHOR'S NAME_.

Copyright (C) _YEAR(S)_. All Rights Reserved. Initial Writer contact(s): _EMAIL OR OTHER CONTACT ADDRESS(ES)_.

Everything that looks _LIKE THIS_ must of course be replaced. If you are not the original author, you should leave his or her notice intact and append the following:


Portions created by _CONTRIBUTOR'S NAME_ are Copyright (C) _YEAR(S)_. All Rights Reserved. Contributor contact(s): _EMAIL OR OTHER CONTACT ADDRESS(ES)_.

There may be several Contributor's sections in the License Notice.

Including a Document History

If your contribution consists of more than a simple change or addition in one spot, also include an appendix called Document History before or after the License Notice. If such an appendix already exists, always enter a description of your modification(s) in it. Please note that even if there's a Document History, you must still add a contributor's section to the License Notice – but then you can fill in “see Document History” in place of the short description.

If you're the original author, it's also perfectly OK to include a Document History in the first version of a document, to serve as a starting point for future revisions. See the first revision element in the example below.

Centerpiece of the Document History is the revhistory element with its children:

    <date>12 Sep 2005</date>
      <para>First version</para>
    <date>5 Dec 2005</date>
      <para>Added information on COALESCE</para>
      <para>Corrected some spelling errors</para>

Please abbreviate the month name in the date element, as the date column in the PDF output is rather narrow.

Below is a Document History example (output view, not source!) that uses a revhistory element. Notice the referral to the CVS tree: we are legally obliged to identify and date all changes. But since CVS already does that, we can simply alert the user to it and give a less extensive but nicer-to-read history in the document itself.

The exact file history is recorded in the manual module in our CVS tree; see

Revision History
1.0 2003 IBP First publication of the free Quick Start Guide.
1.x June 2004 IBP Donated to Firebird Project by IBPhoenix.
2.0 2004 PV Downgraded to Firebird 1.0
Added Classic vs. Superserver section.
Reorganised and corrected Disk Locations Table.
Added (new) screenshots.
Updated and completed information on Control Panel applets.
Added extra examples to “Expressions involving NULL”.
Various other corrections and additions.

If you open the DocBook source of this Guide (src/docs/firebirddocs/docwriting-howto.xml) in your favourite XML editor, you can easily copy-and-paste the Document History and License Notice into your own document. Don't copy the examples given above; copy the real appendices at the end of the document, and edit them to fit your work.

A copyright notice at the start

License Notice and Document History both appear at the end of the document. If you want to make your copyright obvious right from the start, you may also include a short copyright notice in the document's xxxinfo, like this:

    <holder>Tootsie Griff</holder>

Such a notice does not replace the License Notice and/or Document History – it's an extra.

Attaching the entire Pubic Documentation License

Instead of providing the URL, you can also attach the entire PDL to your document. This may especially be useful if your work is a book or long article and you expect (or hope) that people will print it and distribute hardcopies. On a short document the PDL may be a little heavy, but it's your call.

You can get the PDL's DocBook source from src/docs/firebirddocs/licenses.xml. Please note that only the section with the license text itself (including the generic license notice ) belongs to the PDL proper. The Introduction is not part of the license.

If you include the PDL in your document, you can fill in the blanks in section 5.2 of the license. But you may also leave them as they are (provided your name is in the License Notice) or just fill in “the Initial Writer” or “the Copyright holder”.

Translator's notices

Translating a document is a form of modification. So, as a translator, you should:

  • List yourself as a Contributor in the License Notice, with a contribution description like e.g. "Translation into Russian". You may translate the License Notice into the target language if you wish, but you can also leave it in English or include it in both languages.

  • Add a revision element – in the target language – to the revhistory in the Document History. For the revnumber, you use the number of the revision that you've translated, followed by a hyphen and your language code, e.g. “2.0-es” or “1.1-fr”:

      ...previous revisions...
        <date>5 Dec 2005</date>
          <para>Added information on COALESCE</para>
          <para>Corrected some spelling errors</para>
        <date>13 Déc 2005</date>
          <para>Traduction en français</para>
  • Add an othercredit element to the xxxinfo at the beginning of the document, like this:

      <title>Guía de NULL en Firebird</title>
        <contrib>Traducción al castellano</contrib>
      <edition>22 de julio de 2005 - Versión de documento 2.0-es</edition>

    The contrib element contains the same information as the contribution description in the License Notice, but it should always be in the target language.

    Also notice the document version in the edition element – make sure it's the same as in the Document History.

Translating the PDL

You don't have to translate the PDL itself. But if you do:

  • Add it as an independent document to your language's docset, in a book called Licenses (but translate “Licenses” into your language).

  • In the translated Introduction to the PDL, explain that only the English version is legally binding, and include a link to the English version.

  • In any License Notice where you link to the translated PDL, also provide a link to the original PDL and make clear that this is the one that's legally binding.

You can optionally also attach the translated PDL to the document itself, if you don't mind the extra load and bloat.

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