| 1 | <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> |
| 2 | <html> |
| 3 | <head> |
| 4 | <link rel="STYLESHEET" href="lib.css" type='text/css' /> |
| 5 | <link rel="SHORTCUT ICON" href="../icons/pyfav.png" type="image/png" /> |
| 6 | <link rel='start' href='../index.html' title='Python Documentation Index' /> |
| 7 | <link rel="first" href="lib.html" title='Python Library Reference' /> |
| 8 | <link rel='contents' href='contents.html' title="Contents" /> |
| 9 | <link rel='index' href='genindex.html' title='Index' /> |
| 10 | <link rel='last' href='about.html' title='About this document...' /> |
| 11 | <link rel='help' href='about.html' title='About this document...' /> |
| 12 | <link rel="next" href="node339.html" /> |
| 13 | <link rel="prev" href="node328.html" /> |
| 14 | <link rel="parent" href="module-gettext.html" /> |
| 15 | <link rel="next" href="node334.html" /> |
| 16 | <meta name='aesop' content='information' /> |
| 17 | <title>6.28.3 Internationalizing your programs and modules</title> |
| 18 | </head> |
| 19 | <body> |
| 20 | <DIV CLASS="navigation"> |
| 21 | <div id='top-navigation-panel' xml:id='top-navigation-panel'> |
| 22 | <table align="center" width="100%" cellpadding="0" cellspacing="2"> |
| 23 | <tr> |
| 24 | <td class='online-navigation'><a rel="prev" title="6.28.2.4 The Catalog constructor" |
| 25 | href="node332.html"><img src='../icons/previous.png' |
| 26 | border='0' height='32' alt='Previous Page' width='32' /></A></td> |
| 27 | <td class='online-navigation'><a rel="parent" title="6.28 gettext " |
| 28 | href="module-gettext.html"><img src='../icons/up.png' |
| 29 | border='0' height='32' alt='Up One Level' width='32' /></A></td> |
| 30 | <td class='online-navigation'><a rel="next" title="6.28.3.1 Localizing your module" |
| 31 | href="node334.html"><img src='../icons/next.png' |
| 32 | border='0' height='32' alt='Next Page' width='32' /></A></td> |
| 33 | <td align="center" width="100%">Python Library Reference</td> |
| 34 | <td class='online-navigation'><a rel="contents" title="Table of Contents" |
| 35 | href="contents.html"><img src='../icons/contents.png' |
| 36 | border='0' height='32' alt='Contents' width='32' /></A></td> |
| 37 | <td class='online-navigation'><a href="modindex.html" title="Module Index"><img src='../icons/modules.png' |
| 38 | border='0' height='32' alt='Module Index' width='32' /></a></td> |
| 39 | <td class='online-navigation'><a rel="index" title="Index" |
| 40 | href="genindex.html"><img src='../icons/index.png' |
| 41 | border='0' height='32' alt='Index' width='32' /></A></td> |
| 42 | </tr></table> |
| 43 | <div class='online-navigation'> |
| 44 | <b class="navlabel">Previous:</b> |
| 45 | <a class="sectref" rel="prev" href="node332.html">6.28.2.4 The Catalog constructor</A> |
| 46 | <b class="navlabel">Up:</b> |
| 47 | <a class="sectref" rel="parent" href="module-gettext.html">6.28 gettext </A> |
| 48 | <b class="navlabel">Next:</b> |
| 49 | <a class="sectref" rel="next" href="node334.html">6.28.3.1 Localizing your module</A> |
| 50 | </div> |
| 51 | <hr /></div> |
| 52 | </DIV> |
| 53 | <!--End of Navigation Panel--> |
| 54 | |
| 55 | <H2><A NAME="SECTION0082830000000000000000"> |
| 56 | 6.28.3 Internationalizing your programs and modules</A> |
| 57 | </H2> |
| 58 | Internationalization (I18N) refers to the operation by which a program |
| 59 | is made aware of multiple languages. Localization (L10N) refers to |
| 60 | the adaptation of your program, once internationalized, to the local |
| 61 | language and cultural habits. In order to provide multilingual |
| 62 | messages for your Python programs, you need to take the following |
| 63 | steps: |
| 64 | |
| 65 | <P> |
| 66 | |
| 67 | <OL> |
| 68 | <LI>prepare your program or module by specially marking |
| 69 | translatable strings |
| 70 | </LI> |
| 71 | <LI>run a suite of tools over your marked files to generate raw |
| 72 | messages catalogs |
| 73 | </LI> |
| 74 | <LI>create language specific translations of the message catalogs |
| 75 | </LI> |
| 76 | <LI>use the <tt class="module">gettext</tt> module so that message strings are |
| 77 | properly translated |
| 78 | </LI> |
| 79 | </OL> |
| 80 | |
| 81 | <P> |
| 82 | In order to prepare your code for I18N, you need to look at all the |
| 83 | strings in your files. Any string that needs to be translated |
| 84 | should be marked by wrapping it in <code>_('...')</code> -- that is, a call |
| 85 | to the function <tt class="function">_()</tt>. For example: |
| 86 | |
| 87 | <P> |
| 88 | <div class="verbatim"><pre> |
| 89 | filename = 'mylog.txt' |
| 90 | message = _('writing a log message') |
| 91 | fp = open(filename, 'w') |
| 92 | fp.write(message) |
| 93 | fp.close() |
| 94 | </pre></div> |
| 95 | |
| 96 | <P> |
| 97 | In this example, the string <code>'writing a log message'</code> is marked as |
| 98 | a candidate for translation, while the strings <code>'mylog.txt'</code> and |
| 99 | <code>'w'</code> are not. |
| 100 | |
| 101 | <P> |
| 102 | The Python distribution comes with two tools which help you generate |
| 103 | the message catalogs once you've prepared your source code. These may |
| 104 | or may not be available from a binary distribution, but they can be |
| 105 | found in a source distribution, in the <span class="file">Tools/i18n</span> directory. |
| 106 | |
| 107 | <P> |
| 108 | The <b class="program">pygettext</b><A NAME="tex2html45" |
| 109 | HREF="#foot36712"><SUP>6.4</SUP></A> program |
| 110 | scans all your Python source code looking for the strings you |
| 111 | previously marked as translatable. It is similar to the GNU |
| 112 | <b class="program">gettext</b> program except that it understands all the |
| 113 | intricacies of Python source code, but knows nothing about C or C++ |
| 114 | source code. You don't need GNU <code>gettext</code> unless you're also |
| 115 | going to be translating C code (such as C extension modules). |
| 116 | |
| 117 | <P> |
| 118 | <b class="program">pygettext</b> generates textual Uniforum-style human readable |
| 119 | message catalog <span class="file">.pot</span> files, essentially structured human |
| 120 | readable files which contain every marked string in the source code, |
| 121 | along with a placeholder for the translation strings. |
| 122 | <b class="program">pygettext</b> is a command line script that supports a similar |
| 123 | command line interface as <b class="program">xgettext</b>; for details on its use, |
| 124 | run: |
| 125 | |
| 126 | <P> |
| 127 | <div class="verbatim"><pre> |
| 128 | pygettext.py --help |
| 129 | </pre></div> |
| 130 | |
| 131 | <P> |
| 132 | Copies of these <span class="file">.pot</span> files are then handed over to the |
| 133 | individual human translators who write language-specific versions for |
| 134 | every supported natural language. They send you back the filled in |
| 135 | language-specific versions as a <span class="file">.po</span> file. Using the |
| 136 | <b class="program">msgfmt.py</b><A NAME="tex2html46" |
| 137 | HREF="#foot36713"><SUP>6.5</SUP></A> program (in the <span class="file">Tools/i18n</span> directory), you take the |
| 138 | <span class="file">.po</span> files from your translators and generate the |
| 139 | machine-readable <span class="file">.mo</span> binary catalog files. The <span class="file">.mo</span> |
| 140 | files are what the <tt class="module">gettext</tt> module uses for the actual |
| 141 | translation processing during run-time. |
| 142 | |
| 143 | <P> |
| 144 | How you use the <tt class="module">gettext</tt> module in your code depends on |
| 145 | whether you are internationalizing your entire application or a single |
| 146 | module. |
| 147 | |
| 148 | <P> |
| 149 | <BR><HR><H4>Footnotes</H4> |
| 150 | <DL> |
| 151 | <DT><A NAME="foot36712">...pygettext</A><A |
| 152 | HREF="node333.html#tex2html45"><SUP>6.4</SUP></A></DT> |
| 153 | <DD>François Pinard has |
| 154 | written a program called |
| 155 | <b class="program">xpot</b> which does a similar job. It is available as part of |
| 156 | his <b class="program">po-utils</b> package at |
| 157 | <a class="url" href="http://www.iro.umontreal.ca/contrib/po-utils/HTML/">http://www.iro.umontreal.ca/contrib/po-utils/HTML/</a>. |
| 158 | |
| 159 | </DD> |
| 160 | <DT><A NAME="foot36713">...msgfmt.py</A><A |
| 161 | HREF="node333.html#tex2html46"><SUP>6.5</SUP></A></DT> |
| 162 | <DD><b class="program">msgfmt.py</b> is binary |
| 163 | compatible with GNU <b class="program">msgfmt</b> except that it provides a |
| 164 | simpler, all-Python implementation. With this and |
| 165 | <b class="program">pygettext.py</b>, you generally won't need to install the GNU |
| 166 | <b class="program">gettext</b> package to internationalize your Python |
| 167 | applications. |
| 168 | |
| 169 | </DD> |
| 170 | </DL> |
| 171 | <p><br /></p><hr class='online-navigation' /> |
| 172 | <div class='online-navigation'> |
| 173 | <!--Table of Child-Links--> |
| 174 | <A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a> |
| 175 | |
| 176 | <UL CLASS="ChildLinks"> |
| 177 | <LI><A href="node334.html">6.28.3.1 Localizing your module</a> |
| 178 | <LI><A href="node335.html">6.28.3.2 Localizing your application</a> |
| 179 | <LI><A href="node336.html">6.28.3.3 Changing languages on the fly</a> |
| 180 | <LI><A href="node337.html">6.28.3.4 Deferred translations</a> |
| 181 | <LI><A href="node338.html">6.28.3.5 <tt class="function">gettext()</tt> vs. <tt class="function">lgettext()</tt></a> |
| 182 | </ul> |
| 183 | <!--End of Table of Child-Links--> |
| 184 | </div> |
| 185 | |
| 186 | <DIV CLASS="navigation"> |
| 187 | <div class='online-navigation'> |
| 188 | <p></p><hr /> |
| 189 | <table align="center" width="100%" cellpadding="0" cellspacing="2"> |
| 190 | <tr> |
| 191 | <td class='online-navigation'><a rel="prev" title="6.28.2.4 The Catalog constructor" |
| 192 | href="node332.html"><img src='../icons/previous.png' |
| 193 | border='0' height='32' alt='Previous Page' width='32' /></A></td> |
| 194 | <td class='online-navigation'><a rel="parent" title="6.28 gettext " |
| 195 | href="module-gettext.html"><img src='../icons/up.png' |
| 196 | border='0' height='32' alt='Up One Level' width='32' /></A></td> |
| 197 | <td class='online-navigation'><a rel="next" title="6.28.3.1 Localizing your module" |
| 198 | href="node334.html"><img src='../icons/next.png' |
| 199 | border='0' height='32' alt='Next Page' width='32' /></A></td> |
| 200 | <td align="center" width="100%">Python Library Reference</td> |
| 201 | <td class='online-navigation'><a rel="contents" title="Table of Contents" |
| 202 | href="contents.html"><img src='../icons/contents.png' |
| 203 | border='0' height='32' alt='Contents' width='32' /></A></td> |
| 204 | <td class='online-navigation'><a href="modindex.html" title="Module Index"><img src='../icons/modules.png' |
| 205 | border='0' height='32' alt='Module Index' width='32' /></a></td> |
| 206 | <td class='online-navigation'><a rel="index" title="Index" |
| 207 | href="genindex.html"><img src='../icons/index.png' |
| 208 | border='0' height='32' alt='Index' width='32' /></A></td> |
| 209 | </tr></table> |
| 210 | <div class='online-navigation'> |
| 211 | <b class="navlabel">Previous:</b> |
| 212 | <a class="sectref" rel="prev" href="node332.html">6.28.2.4 The Catalog constructor</A> |
| 213 | <b class="navlabel">Up:</b> |
| 214 | <a class="sectref" rel="parent" href="module-gettext.html">6.28 gettext </A> |
| 215 | <b class="navlabel">Next:</b> |
| 216 | <a class="sectref" rel="next" href="node334.html">6.28.3.1 Localizing your module</A> |
| 217 | </div> |
| 218 | </div> |
| 219 | <hr /> |
| 220 | <span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span> |
| 221 | </DIV> |
| 222 | <!--End of Navigation Panel--> |
| 223 | <ADDRESS> |
| 224 | See <i><a href="about.html">About this document...</a></i> for information on suggesting changes. |
| 225 | </ADDRESS> |
| 226 | </BODY> |
| 227 | </HTML> |