Provided by: po4a_0.73-2ubuntu1_all bug

NAME

       po4a - framework to translate documentation and other materials

Introduction

       po4a (PO for anything) eases the maintenance of documentation translation using the classical gettext
       tools. The main feature of po4a is that it decouples the translation of content from its document
       structure.

       This document serves as an introduction to the po4a project with a focus on potential users considering
       whether to use this tool and on the curious wanting to understand why things are the way they are.

Why po4a?

       The philosophy of Free Software is to make the technology truly available to everyone. But licensing is
       not the only consideration: untranslated free software is useless for non-English speakers. Therefore, we
       still have some work to do to make software available to everybody.

       This situation is well understood by most projects and everybody is now convinced of the necessity to
       translate everything. Yet, the actual translations represent a huge effort of many individuals, crippled
       by small technical difficulties.

       Thankfully, Open Source software is actually very well translated using the gettext tool suite. These
       tools are used to extract the strings to translate from a program and present the strings to translate in
       a standardized format (called PO files, or translation catalogs). A whole ecosystem of tools has emerged
       to help the translators actually translate these PO files. The result is then used by gettext at run time
       to display translated messages to the end users.

       Regarding documentation, however, the situation still somewhat disappointing.  At first translating
       documentation may seem to be easier than translating a program as it would seem that you just have to
       copy the documentation source file and start translating the content. However, when the original
       documentation is modified, keeping track of the modifications quickly turns into a nightmare for the
       translators. If done manually, this task is unpleasant and error-prone.

       Outdated translations are often worse than no translation at all. End-users can be tricked by
       documentation describing an old behavior of the program.  Furthermore, they cannot interact directly with
       the maintainers since they don't speak English. Additionally, the maintainer cannot fix the problem as
       they don't know every language in which their documentation is translated.  These difficulties, often
       caused by poor tooling, can undermine the motivation of volunteer translators, further aggravating the
       problem.

       The goal of the po4a project is to ease the work of documentation translators.  In particular, it makes
       documentation translations maintainable.

       The idea is to reuse and adapt the gettext approach to this field. As with gettext, texts are extracted
       from their original locations and presented to translators as PO translation catalogs. The translators
       can leverage the classical gettext tools to monitor the work to do, collaborate and organize as teams.
       po4a then injects the translations directly into the documentation structure to produce translated source
       files that can be processed and distributed just like the English files. Any paragraph that is not
       translated is left in English in the resulting document, ensuring that the end users never see an
       outdated translation in the documentation.

       This automates most of the grunt work of the translation maintenance.  Discovering the paragraphs needing
       an update becomes very easy, and the process is completely automated when elements are reordered without
       further modification. Specific verification can also be used to reduce the chance of formatting errors
       that would result in a broken document.

       Please also see the FAQ below in this document for a more complete list of the advantages and
       disadvantages of this approach.

   Supported formats
       Currently, this approach has been successfully implemented to several kinds of text formatting formats:

       man (mature parser)
           The  good  old manual pages' format, used by so many programs out there. po4a support is very welcome
           here since this format is somewhat difficult to use and not really friendly to newbies.

           The Locale::Po4a::Man(3pm) module also supports the mdoc format, used by the BSD man pages (they  are
           also quite common on Linux).

       AsciiDoc (mature parser)
           This format is a lightweight markup format intended to ease the authoring of documentation. It is for
           example used to document the git system. Those manpages are translated using po4a.

           See Locale::Po4a::AsciiDoc for details.

       pod (mature parser)
           This  is  the Perl Online Documentation format. The language and extensions themselves are documented
           using this format in addition to most existing Perl scripts. It makes easy to keep the  documentation
           close  to the actual code by embedding them both in the same file. It makes programmer's life easier,
           but unfortunately, not the translator's, until you use po4a.

           See Locale::Po4a::Pod for details.

       sgml (mature parser)
           Even if superseded by XML nowadays, this format is still used for documents which are more than a few
           screens long. It can even be used  for  complete  books.   Documents  of  this  length  can  be  very
           challenging  to  update.  diff  often  reveals  useless  when the original text was re-indented after
           update.  Fortunately, po4a can help you after that process.

           Currently, only DebianDoc and DocBook DTD are supported, but adding support for a new one  is  really
           easy.  It  is even possible to use po4a on an unknown SGML DTD without changing the code by providing
           the needed information on the command line. See Locale::Po4a::Sgml(3pm) for details.

       TeX / LaTeX (mature parser)
           The LaTeX format  is  a  major  documentation  format  used  in  the  Free  Software  world  and  for
           publications.

           The  Locale::Po4a::LaTeX(3pm)  module  was  tested  with  the  Python  documentation, a book and some
           presentations.

       text (mature parser)
           The Text format is the base format for many formats that  include  long  blocks  of  text,  including
           Markdown, fortunes, YAML front matter section, debian/changelog, and debian/control.

           This  supports  the  common  format  used in Static Site Generators, READMEs, and other documentation
           systems. See Locale::Po4a::Text(3pm) for details.

       xml and XHMTL (probably mature parser)
           The XML format is a base format for many documentation formats.

           Currently, the DocBook DTD (see Locale::Po4a::Docbook(3pm) for details) and XHTML  are  supported  by
           po4a.

       BibTex (probably mature parser)
           The BibTex format is used alongside LaTex for formatting lists of references (bibliographies).

           See Locale::Po4a::BibTex for details.

       Docbook (probably mature parser)
           A XML-based markup language that uses semantic tags to describe documents.

           See Locale::Po4a:Docbook for greater details.

       Guide XML (probably mature parser)
           A  XML  documentation  format.  This  module  was  developed specifically to help with supporting and
           maintaining translations of Gentoo Linux documentation up until at least March  2016  (Based  on  the
           Wayback Machine). Gentoo have since moved to the DevBook XML format.

           See Locale::Po4a:Guide for greater details.

       Wml (probably mature parser)
           The Web Markup Language, do not mixup WML with the WAP stuff used on cell phones.  This module relies
           on the Xhtml module, which itself relies on the XmL module.

           See Locale::Po4a::Wml for greater details.

       Yaml (probably mature parser)
           A  strict  superset of JSON. YAML is often used as systems or configuration projects.  YAML is at the
           core of Red Hat's Ansible.

           See Locale::Po4a::Yaml for greater details.

       RubyDoc (probably mature parser)
           The Ruby Document (RD) format, originally the default documentation format for Ruby and Ruby projects
           before converted to RDoc in 2002. Though apparently the Japanese version of the Ruby Reference Manual
           still use RD.

           See Locale::Po4a::RubyDoc for greater details.

       Halibut (probably experimental parser)
           A documentation production system, with elements similar to TeX, debiandoc-sgml, TeXinfo, and others,
           developed by Simon Tatham, the developer of PuTTY.

           See Locale::Po4a:Halibut for greater details.

       Ini (probably experimental parser)
           Configuration file format popularized by MS-DOS.

           See Locale::Po4a::Ini for greater details.

       texinfo (very highly experimental parser)
           All of the GNU documentation is written in this format (it's even one of the requirements  to  become
           an  official  GNU  project).  The  support  for  Locale::Po4a::Texinfo(3pm)  in  po4a is still at the
           beginning.  Please report bugs and feature requests.

       gemtext (very highly experimental parser)
           The native plain text format of the Gemini protocol.  The extension ".gmi" is commonly used.  Support
           for this module in po4a is still in its infancy.  If you find anything, please file a bug or  feature
           request.

       Others supported formats
           Po4a  can also handle some more rare or specialized formats, such as the documentation of compilation
           options for the 2.4+ Linux kernels (Locale::Po4a::KernelHelp) or the diagrams  produced  by  the  dia
           tool  (Locale::Po4a:Dia). Adding a new format is often very easy and the main task is to come up with
           a parser for your target format. See Locale::Po4a::TransTractor(3pm) for more information about this.

       Unsupported formats
           Unfortunately, po4a still lacks support for several documentation formats. Many of them would be easy
           to support in po4a. This  includes  formats  not  just  used  for  documentation,  such  as,  package
           descriptions  (deb  and rpm), package installation scripts questions, package changelogs, and all the
           specialized file formats used by programs such as game scenarios or wine resource files.

Using po4a

       The easiest way to use this tool in your project is to write a configuration file for the  po4a  program,
       and  only  interact  with  this  program. Please refer to its documentation, in po4a(1). The rest of this
       section provides more details for the advanced users of po4a wanting to deepen their understanding.

   Detailed schema of the po4a workflow
       Make sure to read po4a(1) before this overly detailed section to get a simplified overview  of  the  po4a
       workflow. Come back here when you want to get the full scary picture, with almost all details.

       In  the following schema, master.doc is an example name for the documentation to be translated; XX.doc is
       the same document translated in the language XX while doc.XX.po  is  the  translation  catalog  for  that
       document in the XX language. Documentation authors will mostly be concerned with master.doc (which can be
       a manpage, an XML document, an AsciidDoc file, etc); the translators will be mostly concerned with the PO
       file, while the end users will only see the XX.doc file.

       Transitions with square brackets such as "[po4a updates po]" represent the execution of a po4a tool while
       transitions  with  curly brackets such as "{update of master.doc}" represent a manual modification of the
       project's files.

                                          master.doc
                                              |
                                              V
            +<-----<----+<-----<-----<--------+------->-------->-------+
            :           |                     |                        :
       {translation}    |          {update of master.doc}              :
            :           |                     |                        :
          XX.doc        |                     V                        V
        (optional)      |                 master.doc ->-------->------>+
            :           |                   (new)                      |
            V           V                     |                        |
         [po4a-gettextize]   doc.XX.po -->+   |                        |
                 |            (old)       |   |                        |
                 |              ^         V   V                        |
                 |              |   [po4a updates po]                  |
                 V              |           |                          V
          translation.pot       ^           V                          |
                 |              |        doc.XX.po                     |
                 |              |         (fuzzy)                      |
           {translation}        |           |                          |
                 |              ^           V                          V
                 |              |     {manual editing}                 |
                 |              |           |                          |
                 V              |           V                          V
             doc.XX.po --->---->+<---<-- doc.XX.po    addendum     master.doc
             (initial)                 (up-to-date)  (optional)   (up-to-date)
                 :                          |            |             |
                 :                          V            |             |
                 +----->----->----->------> +            |             |
                                            |            |             |
                                            V            V             V
                                            +------>-----+------<------+
                                                         |
                                                         V
                                            [po4a updates translations]
                                                         |
                                                         V
                                                       XX.doc
                                                    (up-to-date)

       Again, this schema is overly complicated. Check on po4a(1) for a simplified overview.

       The left part depicts how po4a-gettextize(1) can be used to convert an existing  translation  project  to
       the po4a infrastructure. This script takes an original document and its translated counterpart, and tries
       to   build   the   corresponding   PO  file.  Such  manual  conversion  is  rather  cumbersome  (see  the
       po4a-gettextize(1) documentation for more details), but it is only needed once to convert  your  existing
       translations.  If  you  don't have any translation to convert, you can forget about this and focus on the
       right part of the schema.

       On the top right part, the action of the original author is depicted, updating  the  documentation.   The
       middle  right  part depicts the automatic updates of translation files: the new material is extracted and
       compared against the exiting translation. The previous translation is used  for  the  parts  that  didn't
       change,  while  partially  modified parts are connected to the previous translation with a "fuzzy" marker
       indicating that the translation must be updated. New or heavily modified material is left untranslated.

       Then, the manual editing block depicts the action of the translators, that modify the PO files to provide
       translations to every original string and paragraph. This can be done using either a specific editor such
       as the GNOME Translation Editor, KDE's Lokalize or poedit, or using an online localization platform  such
       as  weblate or pootle. The translation result is a set of PO files, one per language. Please refer to the
       gettext documentation for more details.

       The bottom part of the figure shows how po4a creates a translated source  document  from  the  master.doc
       original  document  and  the  doc.XX.po  translation  catalog  that  was  updated by the translators. The
       structure of the  document  is  reused,  while  the  original  content  is  replaced  by  its  translated
       counterpart. Optionally, an addendum can be used to add some extra text to the translation. This is often
       used to add the name of the translator to the final document. See below for details.

       Upon  invocation,  po4a  updates  both  the  translation  files  and  the  translated documentation files
       automatically.

   Starting a new translation project
       If you start from scratch, you just have to write a configuration file for po4a, and you  are  set.   The
       relevant  templates  are  created  for  the  missing  files, allowing your contributors to translate your
       project to their language. Please refer to po4a(1) for a quick start tutorial and for all details.

       If you have an existing translation, i.e. a documentation file that  was  translated  manually,  you  can
       integrate  its  content  in  your  po4a workflow using po4a-gettextize. This task is a bit cumbersome (as
       described in the tool's manpage), but once your project is converted to po4a workflow, everything will be
       updated automatically.

   Updating the translations and documents
       Once setup, invoking po4a is enough to update both the translation PO files and translated documents. You
       may pass the "--no-translations" to po4a to not update the translations (thus only updating the PO files)
       or "--no-update" to not update  the  PO  files  (thus  only  updating  the  translations).  This  roughly
       corresponds to the individual po4a-updatepo and po4a-translate scripts which are now deprecated (see "Why
       are the individual scripts deprecated" in the FAQ below).

   Using addenda to add extra text to translations
       Adding  new  text  to  the translation is probably the only thing that is easier in the long run when you
       translate files manually :). This happens when you want  to  add  an  extra  section  to  the  translated
       document,  not  corresponding  to any content in the original document. The classical use case is to give
       credits to the translation team, and to indicate how to report translation-specific issues.

       With po4a, you have to specify addendum files, that can be conceptually viewed as patches applied to  the
       localized  document  after processing. Each addendum must be provided as a separate file, which format is
       however very different from the classical patches.  The  first  line  is  a  header  line,  defining  the
       insertion point of the addendum (with an unfortunately cryptic syntax -- see below) while the rest of the
       file is added verbatim at the determined position.

       The  header  line  must  begin  with  the string PO4A-HEADER:, followed by a semi-colon separated list of
       key=value fields.

       For example, the following header declares an addendum that must  be  placed  at  the  very  end  of  the
       translation.

        PO4A-HEADER: mode=eof

       Things  are  more  complex  when  you  want  to add your extra content in the middle of the document. The
       following header declares an addendum that must be placed after the XML  section  containing  the  string
       "About this document" in translation.

        PO4A-HEADER: position=About this document; mode=after; endboundary=</section>

       In  practice,  when trying to apply an addendum, po4a searches for the first line matching the "position"
       argument (this can be a regexp). Do not forget that po4a considers the  translated  document  here.  This
       documentation is in English, but your line should probably read as follows if you intend your addendum to
       apply to the French translation of the document.

        PO4A-HEADER: position=À propos de ce document; mode=after; endboundary=</section>

       Once the "position" is found in the target document, po4a searches for the next line after the "position"
       that matches the provided "endboundary". The addendum is added right after that line (because we provided
       an endboundary, i.e. a boundary ending the current section).

       The exact same effect could be obtained with the following header, that is equivalent:

        PO4A-HEADER: position=About this document; mode=after; beginboundary=<section>

       Here, po4a searches for the first line matching "<section>" after the line matching "About this document"
       in  the  translation,  and  add  the  addendum before that line since we provided a beginboundary, i.e. a
       boundary marking the beginning of the next section. So this header line  requires  placing  the  addendum
       after  the  section containing "About this document", and instruct po4a that a section starts with a line
       containing the "<section>" tag. This is equivalent to the previous example because what you  really  want
       is to add this addendum either after "</section>" or before "<section>".

       You  can  also  set  the  insertion  mode  to  the  value  "before",  with  a similar semantic: combining
       "mode=before" with an "endboundary" will put the addendum just after the matched boundary,  that  is  the
       last  potential boundary line before the "position". Combining "mode=before" with an "beginboundary" will
       put the addendum just before the matched boundary, that is the last potential boundary  line  before  the
       "position".

         Mode   | Boundary kind |     Used boundary      | Insertion point compared to the boundary
        ========|===============|========================|=========================================
        'before'| 'endboundary' | last before 'position' | Right after the selected boundary
        'before'|'beginboundary'| last before 'position' | Right before the selected boundary
        'after' | 'endboundary' | first after 'position' | Right after the selected boundary
        'after' |'beginboundary'| first after 'position' | Right before the selected boundary
        'eof'   |   (none)      |  n/a                   | End of file

       Hint and tricks about addenda

       •   Remember  that  these are regexp. For example, if you want to match the end of a nroff section ending
           with the line ".fi", do not use ".fi" as endboundary, because it will match with "the[ fi]le",  which
           is obviously not what you expect. The correct endboundary in that case is: "^\.fi$".

       •   White  spaces  ARE  important  in  the content of the "position" and boundaries. So the two following
           lines are different. The second one will only be found if there is  enough  trailing  spaces  in  the
           translated document.

            PO4A-HEADER: position=About this document; mode=after; beginboundary=<section>
            PO4A-HEADER: position=About this document ; mode=after; beginboundary=<section>

       •   Although  this  context  search  may  be considered to operate roughly on each line of the translated
           document, it actually operates on the internal data string of the translated document. This  internal
           data  string  may be a text spanning a paragraph containing multiple lines or may be a XML tag itself
           alone. The exact insertion point of the addendum must be before or after the internal data string and
           can not be within the internal data string.

       •   Pass the "-vv" argument to po4a to understand how the addenda are added to the  translation.  It  may
           also  help  to  run po4a in debug mode to see the actual internal data string when your addendum does
           not apply.

       Addenda examples

       •   If you want to add something after the following nroff section:

             .SH "AUTHORS"

           You should select a two-step approach by setting mode=after. Then you should narrow  down  search  to
           the  line after AUTHORS with the position argument regex. Then, you should match the beginning of the
           next section (i.e., ^\.SH) with the beginboundary argument regex. That is to say:

            PO4A-HEADER:mode=after;position=AUTHORS;beginboundary=\.SH

       •   If you want to add something right after a given line (e.g. after the line "Copyright Big Dude"), use
           a position matching this line, mode=after and give a beginboundary matching any line.

            PO4A-HEADER:mode=after;position=Copyright Big Dude, 2004;beginboundary=^

       •   If you want to add something at the end of the document, give a position matching any  line  of  your
           document (but only one line. Po4a won't proceed if it's not unique), and give an endboundary matching
           nothing.  Don't  use simple strings here like "EOF", but prefer those which have less chance to be in
           your document.

            PO4A-HEADER:mode=after;position=About this document;beginboundary=FakePo4aBoundary

       More detailed example

       Original document (POD formatted):

        |=head1 NAME
        |
        |dummy - a dummy program
        |
        |=head1 AUTHOR
        |
        |me

       Then, the following addendum will ensure that a section (in French) about the translator is added at  the
       end of the file (in French, "TRADUCTEUR" means "TRANSLATOR", and "moi" means "me").

        |PO4A-HEADER:mode=after;position=AUTEUR;beginboundary=^=head
        |
        |=head1 TRADUCTEUR
        |
        |moi
        |

       To put your addendum before the AUTHOR, use the following header:

        PO4A-HEADER:mode=after;position=NOM;beginboundary=^=head1

       This  works  because  the  next  line  matching  the  beginboundary  "/^=head1/" after the section "NAME"
       (translated to "NOM" in French), is the one declaring the authors. So, the addendum will be  put  between
       both  sections.  Note  that if another section is added between NAME and AUTHOR sections later, po4a will
       wrongfully put the addenda before the new section.

       To avoid this you may accomplish the same using mode=before:

        PO4A-HEADER:mode=before;position=^=head1 AUTEUR

How does it work?

       This chapter gives you a brief overview of the po4a internals, so that you may  feel  more  confident  to
       help  us  to  maintain  and to improve it. It may also help you to understand why it does not do what you
       expected, and how to solve your problems.

   TransTractors and project architecture
       At the core of the po4a project, the Locale::Po4a::TransTractor(3pm) class is the common ancestor to  all
       po4a  parsers. This strange name comes from the fact that it is at the same time in charge of translating
       document and extracting strings.

       More formally, it takes a document to translate plus a PO file containing  the  translations  to  use  as
       input  while producing two separate outputs: Another PO file (resulting of the extraction of translatable
       strings from the input document), and a translated document (with the same structure as  the  input  one,
       but  with  all  translatable  strings  replaced  with  content  of  the  input  PO).  Here is a graphical
       representation of this:

          Input document --\                             /---> Output document
                            \      TransTractor::       /       (translated)
                             +-->--   parse()  --------+
                            /                           \
          Input PO --------/                             \---> Output PO
                                                              (extracted)

       This little bone is the core of all the po4a architecture. If you provide both input  and  disregard  the
       output  PO,  you get po4a-translate. If you disregard the output document instead, you get po4a-updatepo.
       The po4a uses a first TransTractor to  get  an  up-to-date  output  POT  file  (disregarding  the  output
       documents),  calls  msgmerge  -U  to  update  the  translation  PO  files  on  disk,  and builds a second
       TransTractor with these updated PO files to update the output documents. In short, po4a provides one-stop
       solution to update what needs to be, using a single configuration file.

       po4a-gettextize also uses two TransTractors, but another way: It builds one  TransTractor  per  language,
       and  then  build a new PO file using the msgids of the original document as msgids, and the msgids of the
       translated document as msgstrs. Much care is needed to ensure that the strings matched this way  actually
       match, as described in po4a-gettextize(1).

   Format-specific parsers
       All po4a format parsers are implemented on top of the TransTractor. Some of them are very simple, such as
       the  Text,  Markdown  and  AsciiDoc ones. They load the lines one by one using TransTractor::shiftline(),
       accumulate the paragraphs' content or whatever. Once a string  is  completely  parsed,  the  parser  uses
       TransTractor::translate()  to  (1) add this string to the output PO file and (2) get the translation from
       the input PO file. The parser then pushes the result to the output file using TransTractor::pushline().

       Some other parsers are more complex because they  rely  on  an  external  parser  to  analyze  the  input
       document.  The Xml, HTML, SGML and Pod parsers are built on top of SAX parsers. They declare callbacks to
       events such as "I found a new title which content is the following" to update  the  output  document  and
       output    POT    files   according   to   the   input   content   using   TransTractor::translate()   and
       TransTractor::pushline(). The Yaml parser is similar  but  different:  it  serializes  a  data  structure
       produced  by  the  YAML::Tiny  parser. This is why the Yaml module of po4a fails to declare the reference
       lines: the location of each string in the input file is not kept by the parser, so we  can  only  provide
       "$filename:1"  as  a  string  location. The SAX-oriented parsers use globals and other tricks to save the
       file name and line numbers of references.

       One specific issue arises from file encodings and BOM markers.  Simple  parsers  can  forget  about  this
       issue,  that  is handled by TransTractor::read() (used internally to get the lines of an input document),
       but the modules relying on an external parser must ensure that all files are  read  with  an  appropriate
       PerlIO  decoding  layer.  The easiest is to open the file yourself, and provide an filehandle or directly
       the full string to your external parser. Check on  Pod::read()  and  Pod::parse()  for  an  example.  The
       content read by the TransTractor is ignored, but a fresh filehandle is passed to the external parser. The
       important part is the "<:encoding($charset)" mode that is passed to the open() perl function.

   Po objects
       The  Locale::Po4a::Po(3pm)  class  is in charge of loading and using PO and POT files. Basically, you can
       read a file, add entries, get translations with the gettext() method, write the  PO  into  a  file.  More
       advanced  features  such  as  merging  a PO file against a POT file or validating a file are delegated to
       msgmerge and msgfmt respectively.

   Contributing to po4a
       Even if you have never contributed to any Open Source project in  the  past,  you  are  welcome:  we  are
       willing  to help and mentor you here. po4a is best maintained by its users nowadays. As we lack manpower,
       we try to make the project welcoming by improving the doc and the automatic tests to make  you  confident
       in contributing to the project. Please refer to the CONTRIBUTING.md file for more details.

Open-source projects using po4a

       Here  is a very partial list of projects that use po4a in production for their documentation. If you want
       to add your project to the list, just drop us an email (or a Merge Request).

       •   adduser (man): users and groups management tool.

       •   apt (man, docbook): Debian package manager.

       •   aptitude (docbook, svg): terminal-based package manager for Debian

       •   F-Droid website <https://gitlab.com/fdroid/fdroid-website> (markdown): installable  catalog  of  FOSS
           (Free and Open Source Software) applications for the Android platform.

       •   git <https://github.com/jnavila/git-manpages-l10n> (asciidoc): distributed version-control system for
           tracking changes in source code.

       •   Linux manpages <https://salsa.debian.org/manpages-l10n-team/manpages-l10n> (man)

           This  project  provides an infrastructure for translating many manpages to different languages, ready
           for integration into several major distributions (Arch Linux, Debian and derivatives, Fedora).

       •   Stellarium <https://github.com/Stellarium/stellarium> (HTML): a free open source planetarium for your
           computer. po4a is used to translate the sky culture descriptions.

       •   Jamulus <https://jamulus.io/> (markdown, yaml, HTML): a FOSS application for online jamming  in  real
           time. The website documentation is maintained in multiple languages using po4a.

       •   Other        item        to        sort        out:       <https://gitlab.com/fdroid/fdroid-website/>
           <https://github.com/fsfe/reuse-docs/pull/61>

FAQ

   How do you pronounce po4a?
       I personally vocalize it as pouah <https://en.wiktionary.org/wiki/pouah>, which is a French onomatopoetic
       that we use in place of yuck :) I may have a strange sense of humor :)

   Why are the individual scripts deprecated?
       Indeed, po4a-updatepo and po4a-translate are deprecated in favor of po4a. The reason is that  while  po4a
       can  be  used  as  a drop-in replacement to these scripts, there is quite a lot of code duplication here.
       Individual scripts last around 150 lines of codes while the po4a program lasts 1200 lines, so they  do  a
       lot  in  addition of the common internals. The code duplication results in bugs occuring in both versions
       and needing two fixes. One example of such duplication are the bugs #1022216 in Debian and the issue #442
       in GitHub that had the exact same fix, but one in po4a and the other po4a-updatepo.

       In the long run, I would like to drop the individual scripts and only maintain one version of this  code.
       The  sure  thing  is that the individual scripts will not get improved anymore, so only po4a will get the
       new features. That being said, there is no deprecation urgency. I plan to keep the individual scripts  as
       long  as possible, and at least until 2030. If your project still use po4a-updatepo and po4a-translate in
       2030, you may have a problem.

       We may also remove the deprecation of these scripts at some point, if  a  refactoring  reduces  the  code
       duplication to zero. If you have an idea (or better: a patch), your help is welcome.

   What about the other translation tools for documentation using gettext?
       There are a few of them. Here is a possibly incomplete list, and more tools are coming at the horizon.

       poxml
           This  is  the  tool developed by KDE people to handle DocBook XML. AFAIK, it was the first program to
           extract strings to translate from documentation to PO files, and inject them back after translation.

           It can only handle XML, and only a particular DTD. I'm quite unhappy  with  the  handling  of  lists,
           which end in one big msgid. When the list become big, the chunk becomes harder to swallow.

       po-debiandoc
           This program done by Denis Barbier is a sort of precursor of the po4a SGML module, which more or less
           deprecates  it.  As  the  name  says,  it  handles  only  the  DebianDoc DTD, which is more or less a
           deprecated DTD.

       xml2po.py
           Used by the GIMP Documentation Team since 2004, works quite well even if, as the name suggests,  only
           with XML files and needs specially configured makefiles.

       Sphinx
           The  Sphinx  Documentation  Project  also  uses  gettext  extensively  to  manage  its  translations.
           Unfortunately, it works only for a few text formats, rest and markdown, although it  is  perhaps  the
           only tool that does this managing the whole translation process.

       The  main advantages of po4a over them are the ease of extra content addition (which is even worse there)
       and the ability to achieve gettextization.

   SUMMARY of the advantages of the gettext based approach
       • The translations are not stored along  with  the  original,  which  makes  it  possible  to  detect  if
         translations become out of date.

       • The  translations are stored in separate files from each other, which prevents translators of different
         languages from interfering, both when submitting their patch and at the file encoding level.

       • It is based internally on gettext (but po4a offers a very simple interface so that you  don't  need  to
         understand the internals to use it).  That way, we don't have to re-implement the wheel, and because of
         their wide use, we can think that these tools are more or less bug free.

       • Nothing  changed  for  the end-user (beside the fact translations will hopefully be better maintained).
         The resulting documentation file distributed is exactly the same.

       • No need for translators to learn a new file syntax and their favorite PO file editor  (like  Emacs'  PO
         mode, Lokalize or Gtranslator) will work just fine.

       • gettext  offers a simple way to get statistics about what is done, what should be reviewed and updated,
         and what is still to do. Some example can be found at those addresses:

          - https://docs.kde.org/stable5/en/kdesdk/lokalize/project-view.html
          - http://www.debian.org/intl/l10n/

       But everything isn't green, and this approach also has some disadvantages we have to deal with.

       • Addenda are somewhat strange at the first glance.

       • You can't adapt the translated text to your preferences, like splitting a paragraph here,  and  joining
         two  other ones there. But in some sense, if there is an issue with the original, it should be reported
         as a bug anyway.

       • Even with an easy interface, it remains a new tool people have to learn.

         One of my dreams would be to integrate somehow po4a to Gtranslator or Lokalize.  When  a  documentation
         file is opened, the strings are automatically extracted, and a translated file + po file can be written
         to  disk. If we manage to do an MS Word (TM) module (or at least RTF) professional translators may even
         use it.

SEE ALSO

       •   The documentation of the all-in-one tool that you should use: po4a(1).

       •   The  documentation  of   the   individual   po4a   scripts:   po4a-gettextize(1),   po4a-updatepo(1),
           po4a-translate(1), po4a-normalize(1).

       •   The additional helping scripts: msguntypot(1), po4a-display-man(1), po4a-display-pod(1).

       •   The  parsers  of  each  formats,  in  particular  to  see  the  options  accepted  by  each  of them:
           Locale::Po4a::AsciiDoc(3pm) Locale::Po4a::Dia(3pm), Locale::Po4a::Guide(3pm), Locale::Po4a::Ini(3pm),
           Locale::Po4a::KernelHelp(3pm),          Locale::Po4a::Man(3pm),           Locale::Po4a::RubyDoc(3pm),
           Locale::Po4a::Texinfo(3pm),             Locale::Po4a::Text(3pm),            Locale::Po4a::Xhtml(3pm),
           Locale::Po4a::Yaml(3pm),            Locale::Po4a::BibTeX(3pm),            Locale::Po4a::Docbook(3pm),
           Locale::Po4a::Halibut(3pm),             Locale::Po4a::LaTeX(3pm),             Locale::Po4a::Pod(3pm),
           Locale::Po4a::Sgml(3pm), Locale::Po4a::TeX(3pm), Locale::Po4a::Wml(3pm), Locale::Po4a::Xml(3pm).

       •   The  implementation  of  the  core  infrastructure:   Locale::Po4a::TransTractor(3pm)   (particularly
           important  to  understand  the code organization), Locale::Po4a::Chooser(3pm), Locale::Po4a::Po(3pm),
           Locale::Po4a::Common(3pm). Please also check the CONTRIBUTING.md file in the source tree.

AUTHORS

        Denis Barbier <barbier,linuxfr.org>
        Martin Quinson (mquinson#debian.org)

perl v5.38.2                                       2024-08-28                                          PO4A.7(1)