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<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>57.1. For the Translator</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="nls.html" title="Chapter 57. Native Language Support" /><link rel="next" href="nls-programmer.html" title="57.2. For the Programmer" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">57.1. For the Translator</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="nls.html" title="Chapter 57. Native Language Support">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="nls.html" title="Chapter 57. Native Language Support">Up</a></td><th width="60%" align="center">Chapter 57. Native Language Support</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="nls-programmer.html" title="57.2. For the Programmer">Next</a></td></tr></table><hr /></div><div class="sect1" id="NLS-TRANSLATOR"><div class="titlepage"><div><div><h2 class="title" style="clear: both">57.1. For the Translator</h2></div></div></div><div class="toc"><dl class="toc"><dt><span class="sect2"><a href="nls-translator.html#id-1.10.8.2.3">57.1.1. Requirements</a></span></dt><dt><span class="sect2"><a href="nls-translator.html#id-1.10.8.2.4">57.1.2. Concepts</a></span></dt><dt><span class="sect2"><a href="nls-translator.html#id-1.10.8.2.5">57.1.3. Creating and Maintaining Message Catalogs</a></span></dt><dt><span class="sect2"><a href="nls-translator.html#id-1.10.8.2.6">57.1.4. Editing the PO Files</a></span></dt></dl></div><p>
   <span class="productname">PostgreSQL</span>
   programs (server and client) can issue their messages in
   your favorite language — if the messages have been translated.
   Creating and maintaining translated message sets needs the help of
   people who speak their own language well and want to contribute to
   the <span class="productname">PostgreSQL</span> effort.  You do not have to be a
   programmer at all
   to do this.  This section explains how to help.
  </p><div class="sect2" id="id-1.10.8.2.3"><div class="titlepage"><div><div><h3 class="title">57.1.1. Requirements</h3></div></div></div><p>
    We won't judge your language skills — this section is about
    software tools.  Theoretically, you only need a text editor.  But
    this is only in the unlikely event that you do not want to try out
    your translated messages.  When you configure your source tree, be
    sure to use the <code class="option">--enable-nls</code> option.  This will
    also check for the <span class="application">libintl</span> library and the
    <code class="filename">msgfmt</code> program, which all end users will need
    anyway.  To try out your work, follow the applicable portions of
    the installation instructions.
   </p><p>
    If you want to start a new translation effort or want to do a
    message catalog merge (described later), you will need the
    programs <code class="filename">xgettext</code> and
    <code class="filename">msgmerge</code>, respectively, in a GNU-compatible
    implementation.  Later, we will try to arrange it so that if you
    use a packaged source distribution, you won't need
    <code class="filename">xgettext</code>.  (If working from Git, you will still need
    it.)  <span class="application">GNU Gettext 0.10.36</span> or later is currently recommended.
   </p><p>
    Your local gettext implementation should come with its own
    documentation.  Some of that is probably duplicated in what
    follows, but for additional details you should look there.
   </p></div><div class="sect2" id="id-1.10.8.2.4"><div class="titlepage"><div><div><h3 class="title">57.1.2. Concepts</h3></div></div></div><p>
    The pairs of original (English) messages and their (possibly)
    translated equivalents are kept in <em class="firstterm">message
    catalogs</em>, one for each program (although related
    programs can share a message catalog) and for each target
    language.  There are two file formats for message catalogs:  The
    first is the <span class="quote"><span class="quote">PO</span></span> file (for Portable Object), which
    is a plain text file with special syntax that translators edit.
    The second is the <span class="quote"><span class="quote">MO</span></span> file (for Machine Object),
    which is a binary file generated from the respective PO file and
    is used while the internationalized program is run.  Translators
    do not deal with MO files; in fact hardly anyone does.
   </p><p>
    The extension of the message catalog file is to no surprise either
    <code class="filename">.po</code> or <code class="filename">.mo</code>.  The base
    name is either the name of the program it accompanies, or the
    language the file is for, depending on the situation.  This is a
    bit confusing.  Examples are <code class="filename">psql.po</code> (PO file
    for psql) or <code class="filename">fr.mo</code> (MO file in French).
   </p><p>
    The file format of the PO files is illustrated here:
</p><pre class="programlisting">
# comment

msgid "original string"
msgstr "translated string"

msgid "more original"
msgstr "another translated"
"string can be broken up like this"

...
</pre><p>
    The msgid lines are extracted from the program source.  (They need not
    be, but this is the most common way.)  The msgstr lines are
    initially empty and are filled in with useful strings by the
    translator.  The strings can contain C-style escape characters and
    can be continued across lines as illustrated.  (The next line must
    start at the beginning of the line.)
   </p><p>
    The # character introduces a comment.  If whitespace immediately
    follows the # character, then this is a comment maintained by the
    translator.  There can also be automatic comments, which have a
    non-whitespace character immediately following the #.  These are
    maintained by the various tools that operate on the PO files and
    are intended to aid the translator.
</p><pre class="programlisting">
#. automatic comment
#: filename.c:1023
#, flags, flags
</pre><p>
    The #. style comments are extracted from the source file where the
    message is used.  Possibly the programmer has inserted information
    for the translator, such as about expected alignment.  The #:
    comments indicate the exact locations where the message is used
    in the source.  The translator need not look at the program
    source, but can if there is doubt about the correct
    translation.  The #, comments contain flags that describe the
    message in some way.  There are currently two flags:
    <code class="literal">fuzzy</code> is set if the message has possibly been
    outdated because of changes in the program source.  The translator
    can then verify this and possibly remove the fuzzy flag.  Note
    that fuzzy messages are not made available to the end user.  The
    other flag is <code class="literal">c-format</code>, which indicates that
    the message is a <code class="function">printf</code>-style format
    template.  This means that the translation should also be a format
    string with the same number and type of placeholders.  There are
    tools that can verify this, which key off the c-format flag.
   </p></div><div class="sect2" id="id-1.10.8.2.5"><div class="titlepage"><div><div><h3 class="title">57.1.3. Creating and Maintaining Message Catalogs</h3></div></div></div><p>
    OK, so how does one create a <span class="quote"><span class="quote">blank</span></span> message
    catalog?  First, go into the directory that contains the program
    whose messages you want to translate.  If there is a file
    <code class="filename">nls.mk</code>, then this program has been prepared
    for translation.
   </p><p>
    If there are already some <code class="filename">.po</code> files, then
    someone has already done some translation work.  The files are
    named <code class="filename"><em class="replaceable"><code>language</code></em>.po</code>,
    where <em class="replaceable"><code>language</code></em> is the
    <a class="ulink" href="https://www.loc.gov/standards/iso639-2/php/English_list.php" target="_top">
    ISO 639-1 two-letter language code (in lower case)</a>, e.g.,
    <code class="filename">fr.po</code> for French.  If there is really a need
    for more than one translation effort per language then the files
    can also be named
    <code class="filename"><em class="replaceable"><code>language</code></em>_<em class="replaceable"><code>region</code></em>.po</code>
    where <em class="replaceable"><code>region</code></em> is the
    <a class="ulink" href="https://www.iso.org/iso-3166-country-codes.html" target="_top">
    ISO 3166-1 two-letter country code (in upper case)</a>,
    e.g.,
    <code class="filename">pt_BR.po</code> for Portuguese in Brazil.  If you
    find the language you wanted you can just start working on that
    file.
   </p><p>
    If you need to start a new translation effort, then first run the
    command:
</p><pre class="programlisting">
make init-po
</pre><p>
    This will create a file
    <code class="filename"><em class="replaceable"><code>progname</code></em>.pot</code>.
    (<code class="filename">.pot</code> to distinguish it from PO files that
    are <span class="quote"><span class="quote">in production</span></span>. The <code class="literal">T</code> stands for
    <span class="quote"><span class="quote">template</span></span>.)
    Copy this file to
    <code class="filename"><em class="replaceable"><code>language</code></em>.po</code> and
    edit it.  To make it known that the new language is available,
    also edit the file <code class="filename">nls.mk</code> and add the
    language (or language and country) code to the line that looks like:
</p><pre class="programlisting">
AVAIL_LANGUAGES := de fr
</pre><p>
    (Other languages can appear, of course.)
   </p><p>
    As the underlying program or library changes, messages might be
    changed or added by the programmers.  In this case you do not need
    to start from scratch.  Instead, run the command:
</p><pre class="programlisting">
make update-po
</pre><p>
    which will create a new blank message catalog file (the pot file
    you started with) and will merge it with the existing PO files.
    If the merge algorithm is not sure about a particular message it
    marks it <span class="quote"><span class="quote">fuzzy</span></span> as explained above.  The new PO file
    is saved with a <code class="filename">.po.new</code> extension.
   </p></div><div class="sect2" id="id-1.10.8.2.6"><div class="titlepage"><div><div><h3 class="title">57.1.4. Editing the PO Files</h3></div></div></div><p>
    The PO files can be edited with a regular text editor.  The
    translator should only change the area between the quotes after
    the msgstr directive, add comments, and alter the fuzzy flag.
    There is (unsurprisingly) a PO mode for Emacs, which I find quite
    useful.
   </p><p>
    The PO files need not be completely filled in.  The software will
    automatically fall back to the original string if no translation
    (or an empty translation) is available.  It is no problem to
    submit incomplete translations for inclusions in the source tree;
    that gives room for other people to pick up your work.  However,
    you are encouraged to give priority to removing fuzzy entries
    after doing a merge.  Remember that fuzzy entries will not be
    installed; they only serve as reference for what might be the right
    translation.
   </p><p>
    Here are some things to keep in mind while editing the
    translations:
    </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
       Make sure that if the original ends with a newline, the
       translation does, too.  Similarly for tabs, etc.
      </p></li><li class="listitem"><p>
       If the original is a <code class="function">printf</code> format string, the translation
       also needs to be.  The translation also needs to have the same
       format specifiers in the same order.  Sometimes the natural
       rules of the language make this impossible or at least awkward.
       In that case you can modify the format specifiers like this:
</p><pre class="programlisting">
msgstr "Die Datei %2$s hat %1$u Zeichen."
</pre><p>
       Then the first placeholder will actually use the second
       argument from the list.  The
       <code class="literal"><em class="replaceable"><code>digits</code></em>$</code> needs to
       follow the % immediately, before any other format manipulators.
       (This feature really exists in the <code class="function">printf</code>
       family of functions.  You might not have heard of it before because
       there is little use for it outside of message
       internationalization.)
      </p></li><li class="listitem"><p>
       If the original string contains a linguistic mistake, report
       that (or fix it yourself in the program source) and translate
       normally.  The corrected string can be merged in when the
       program sources have been updated.  If the original string
       contains a factual mistake, report that (or fix it yourself)
       and do not translate it.  Instead, you can mark the string with
       a comment in the PO file.
      </p></li><li class="listitem"><p>
       Maintain the style and tone of the original string.
       Specifically, messages that are not sentences (<code class="literal">cannot
       open file %s</code>) should probably not start with a
       capital letter (if your language distinguishes letter case) or
       end with a period (if your language uses punctuation marks).
       It might help to read <a class="xref" href="error-style-guide.html" title="56.3. Error Message Style Guide">Section 56.3</a>.
      </p></li><li class="listitem"><p>
       If you don't know what a message means, or if it is ambiguous,
       ask on the developers' mailing list.  Chances are that English
       speaking end users might also not understand it or find it
       ambiguous, so it's best to improve the message.
      </p></li></ul></div><p>
   </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="nls.html" title="Chapter 57. Native Language Support">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="nls.html" title="Chapter 57. Native Language Support">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="nls-programmer.html" title="57.2. For the Programmer">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 57. Native Language Support </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 15.4 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 57.2. For the Programmer</td></tr></table></div></body></html>