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diff --git a/gcc-4.4.3/libstdc++-v3/doc/html/manual/messages.html b/gcc-4.4.3/libstdc++-v3/doc/html/manual/messages.html deleted file mode 100644 index 67327cc27..000000000 --- a/gcc-4.4.3/libstdc++-v3/doc/html/manual/messages.html +++ /dev/null @@ -1,284 +0,0 @@ -<?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>messages</title><meta name="generator" content="DocBook XSL Stylesheets V1.74.0" /><meta name="keywords" content=" ISO C++ , messages " /><meta name="keywords" content=" ISO C++ , library " /><link rel="home" href="../spine.html" title="The GNU C++ Library Documentation" /><link rel="up" href="facets.html" title="Chapter 15. Facets aka Categories" /><link rel="prev" href="codecvt.html" title="codecvt" /><link rel="next" href="containers.html" title="Part VII. Containers" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">messages</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="codecvt.html">Prev</a> </td><th width="60%" align="center">Chapter 15. Facets aka Categories</th><td width="20%" align="right"> <a accesskey="n" href="containers.html">Next</a></td></tr></table><hr /></div><div class="sect1" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="manual.localization.facet.messages"></a>messages</h2></div></div></div><p> -The std::messages facet implements message retrieval functionality -equivalent to Java's java.text.MessageFormat .using either GNU gettext -or IEEE 1003.1-200 functions. -</p><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="facet.messages.req"></a>Requirements</h3></div></div></div><p> -The std::messages facet is probably the most vaguely defined facet in -the standard library. It's assumed that this facility was built into -the standard library in order to convert string literals from one -locale to the other. For instance, converting the "C" locale's -<code class="code">const char* c = "please"</code> to a German-localized <code class="code">"bitte"</code> -during program execution. -</p><div class="blockquote"><blockquote class="blockquote"><p> -22.2.7.1 - Template class messages [lib.locale.messages] -</p></blockquote></div><p> -This class has three public member functions, which directly -correspond to three protected virtual member functions. -</p><p> -The public member functions are: -</p><p> -<code class="code">catalog open(const string&, const locale&) const</code> -</p><p> -<code class="code">string_type get(catalog, int, int, const string_type&) const</code> -</p><p> -<code class="code">void close(catalog) const</code> -</p><p> -While the virtual functions are: -</p><p> -<code class="code">catalog do_open(const string&, const locale&) const</code> -</p><div class="blockquote"><blockquote class="blockquote"><p> -<span class="emphasis"><em> --1- Returns: A value that may be passed to get() to retrieve a -message, from the message catalog identified by the string name -according to an implementation-defined mapping. The result can be used -until it is passed to close(). Returns a value less than 0 if no such -catalog can be opened. -</em></span> -</p></blockquote></div><p> -<code class="code">string_type do_get(catalog, int, int, const string_type&) const</code> -</p><div class="blockquote"><blockquote class="blockquote"><p> -<span class="emphasis"><em> --3- Requires: A catalog cat obtained from open() and not yet closed. --4- Returns: A message identified by arguments set, msgid, and dfault, -according to an implementation-defined mapping. If no such message can -be found, returns dfault. -</em></span> -</p></blockquote></div><p> -<code class="code">void do_close(catalog) const</code> -</p><div class="blockquote"><blockquote class="blockquote"><p> -<span class="emphasis"><em> --5- Requires: A catalog cat obtained from open() and not yet closed. --6- Effects: Releases unspecified resources associated with cat. --7- Notes: The limit on such resources, if any, is implementation-defined. -</em></span> -</p></blockquote></div></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="facet.messages.design"></a>Design</h3></div></div></div><p> -A couple of notes on the standard. -</p><p> -First, why is <code class="code">messages_base::catalog</code> specified as a typedef -to int? This makes sense for implementations that use -<code class="code">catopen</code>, but not for others. Fortunately, it's not heavily -used and so only a minor irritant. -</p><p> -Second, by making the member functions <code class="code">const</code>, it is -impossible to save state in them. Thus, storing away information used -in the 'open' member function for use in 'get' is impossible. This is -unfortunate. -</p><p> -The 'open' member function in particular seems to be oddly -designed. The signature seems quite peculiar. Why specify a <code class="code">const -string& </code> argument, for instance, instead of just <code class="code">const -char*</code>? Or, why specify a <code class="code">const locale&</code> argument that is -to be used in the 'get' member function? How, exactly, is this locale -argument useful? What was the intent? It might make sense if a locale -argument was associated with a given default message string in the -'open' member function, for instance. Quite murky and unclear, on -reflection. -</p><p> -Lastly, it seems odd that messages, which explicitly require code -conversion, don't use the codecvt facet. Because the messages facet -has only one template parameter, it is assumed that ctype, and not -codecvt, is to be used to convert between character sets. -</p><p> -It is implicitly assumed that the locale for the default message -string in 'get' is in the "C" locale. Thus, all source code is assumed -to be written in English, so translations are always from "en_US" to -other, explicitly named locales. -</p></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="facet.messages.impl"></a>Implementation</h3></div></div></div><div class="sect3" lang="en" xml:lang="en"><div class="titlepage"><div><div><h4 class="title"><a id="messages.impl.models"></a>Models</h4></div></div></div><p> - This is a relatively simple class, on the face of it. The standard - specifies very little in concrete terms, so generic - implementations that are conforming yet do very little are the - norm. Adding functionality that would be useful to programmers and - comparable to Java's java.text.MessageFormat takes a bit of work, - and is highly dependent on the capabilities of the underlying - operating system. - </p><p> - Three different mechanisms have been provided, selectable via - configure flags: - </p><div class="itemizedlist"><ul type="disc"><li><p> - generic - </p><p> - This model does very little, and is what is used by default. - </p></li><li><p> - gnu - </p><p> - The gnu model is complete and fully tested. It's based on the - GNU gettext package, which is part of glibc. It uses the - functions <code class="code">textdomain, bindtextdomain, gettext</code> to - implement full functionality. Creating message catalogs is a - relatively straight-forward process and is lightly documented - below, and fully documented in gettext's distributed - documentation. - </p></li><li><p> - ieee_1003.1-200x - </p><p> - This is a complete, though untested, implementation based on - the IEEE standard. The functions <code class="code">catopen, catgets, - catclose</code> are used to retrieve locale-specific messages - given the appropriate message catalogs that have been - constructed for their use. Note, the script <code class="code"> - po2msg.sed</code> that is part of the gettext distribution can - convert gettext catalogs into catalogs that - <code class="code">catopen</code> can use. - </p></li></ul></div><p> -A new, standards-conformant non-virtual member function signature was -added for 'open' so that a directory could be specified with a given -message catalog. This simplifies calling conventions for the gnu -model. -</p></div><div class="sect3" lang="en" xml:lang="en"><div class="titlepage"><div><div><h4 class="title"><a id="messages.impl.gnu"></a>The GNU Model</h4></div></div></div><p> - The messages facet, because it is retrieving and converting - between characters sets, depends on the ctype and perhaps the - codecvt facet in a given locale. In addition, underlying "C" - library locale support is necessary for more than just the - <code class="code">LC_MESSAGES</code> mask: <code class="code">LC_CTYPE</code> is also - necessary. To avoid any unpleasantness, all bits of the "C" mask - (i.e. <code class="code">LC_ALL</code>) are set before retrieving messages. - </p><p> - Making the message catalogs can be initially tricky, but become - quite simple with practice. For complete info, see the gettext - documentation. Here's an idea of what is required: - </p><div class="itemizedlist"><ul type="disc"><li><p> - Make a source file with the required string literals that need - to be translated. See <code class="code">intl/string_literals.cc</code> for - an example. - </p></li><li><p> - Make initial catalog (see "4 Making the PO Template File" from - the gettext docs).</p><p> - <code class="code"> xgettext --c++ --debug string_literals.cc -o libstdc++.pot </code> - </p></li><li><p>Make language and country-specific locale catalogs.</p><p> - <code class="code">cp libstdc++.pot fr_FR.po</code> - </p><p> - <code class="code">cp libstdc++.pot de_DE.po</code> - </p></li><li><p> - Edit localized catalogs in emacs so that strings are - translated. - </p><p> - <code class="code">emacs fr_FR.po</code> - </p></li><li><p>Make the binary mo files.</p><p> - <code class="code">msgfmt fr_FR.po -o fr_FR.mo</code> - </p><p> - <code class="code">msgfmt de_DE.po -o de_DE.mo</code> - </p></li><li><p>Copy the binary files into the correct directory structure.</p><p> - <code class="code">cp fr_FR.mo (dir)/fr_FR/LC_MESSAGES/libstdc++.mo</code> - </p><p> - <code class="code">cp de_DE.mo (dir)/de_DE/LC_MESSAGES/libstdc++.mo</code> - </p></li><li><p>Use the new message catalogs.</p><p> - <code class="code">locale loc_de("de_DE");</code> - </p><p> - <code class="code"> - use_facet<messages<char> >(loc_de).open("libstdc++", locale(), dir); - </code> - </p></li></ul></div></div></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="facet.messages.use"></a>Use</h3></div></div></div><p> - A simple example using the GNU model of message conversion. - </p><pre class="programlisting"> -#include <iostream> -#include <locale> -using namespace std; - -void test01() -{ - typedef messages<char>::catalog catalog; - const char* dir = - "/mnt/egcs/build/i686-pc-linux-gnu/libstdc++/po/share/locale"; - const locale loc_de("de_DE"); - const messages<char>& mssg_de = use_facet<messages<char> >(loc_de); - - catalog cat_de = mssg_de.open("libstdc++", loc_de, dir); - string s01 = mssg_de.get(cat_de, 0, 0, "please"); - string s02 = mssg_de.get(cat_de, 0, 0, "thank you"); - cout << "please in german:" << s01 << '\n'; - cout << "thank you in german:" << s02 << '\n'; - mssg_de.close(cat_de); -} -</pre></div><div class="sect2" lang="en" xml:lang="en"><div class="titlepage"><div><div><h3 class="title"><a id="facet.messages.future"></a>Future</h3></div></div></div><div class="itemizedlist"><ul type="disc"><li><p> - Things that are sketchy, or remain unimplemented: - </p><div class="itemizedlist"><ul type="circle"><li><p> - _M_convert_from_char, _M_convert_to_char are in flux, - depending on how the library ends up doing character set - conversions. It might not be possible to do a real character - set based conversion, due to the fact that the template - parameter for messages is not enough to instantiate the - codecvt facet (1 supplied, need at least 2 but would prefer - 3). - </p></li><li><p> - There are issues with gettext needing the global locale set - to extract a message. This dependence on the global locale - makes the current "gnu" model non MT-safe. Future versions - of glibc, i.e. glibc 2.3.x will fix this, and the C++ library - bits are already in place. - </p></li></ul></div></li><li><p> - Development versions of the GNU "C" library, glibc 2.3 will allow - a more efficient, MT implementation of std::messages, and will - allow the removal of the _M_name_messages data member. If this is - done, it will change the library ABI. The C++ parts to support - glibc 2.3 have already been coded, but are not in use: once this - version of the "C" library is released, the marked parts of the - messages implementation can be switched over to the new "C" - library functionality. - </p></li><li><p> - At some point in the near future, std::numpunct will probably use - std::messages facilities to implement truename/falsename - correctly. This is currently not done, but entries in - libstdc++.pot have already been made for "true" and "false" string - literals, so all that remains is the std::numpunct coding and the - configure/make hassles to make the installed library search its - own catalog. Currently the libstdc++.mo catalog is only searched - for the testsuite cases involving messages members. - </p></li><li><p> The following member functions:</p><p> - <code class="code"> - catalog - open(const basic_string<char>& __s, const locale& __loc) const - </code> - </p><p> - <code class="code"> - catalog - open(const basic_string<char>&, const locale&, const char*) const; - </code> - </p><p> - Don't actually return a "value less than 0 if no such catalog - can be opened" as required by the standard in the "gnu" - model. As of this writing, it is unknown how to query to see - if a specified message catalog exists using the gettext - package. - </p></li></ul></div></div><div class="bibliography"><div class="titlepage"><div><div><h3 class="title"><a id="facet.messages.biblio"></a>Bibliography</h3></div></div></div><div class="biblioentry"><a id="id427517"></a><p><span class="title"><i> - The GNU C Library - </i>. </span><span class="author"><span class="firstname">Roland</span> <span class="surname">McGrath</span>. </span><span class="author"><span class="firstname">Ulrich</span> <span class="surname">Drepper</span>. </span><span class="copyright">Copyright © 2007 FSF. </span><span class="pagenums">Chapters 6 Character Set Handling, and 7 Locales and Internationalization - . </span></p></div><div class="biblioentry"><a id="id391329"></a><p><span class="title"><i> - Correspondence - </i>. </span><span class="author"><span class="firstname">Ulrich</span> <span class="surname">Drepper</span>. </span><span class="copyright">Copyright © 2002 . </span></p></div><div class="biblioentry"><a id="id391358"></a><p><span class="title"><i> - ISO/IEC 14882:1998 Programming languages - C++ - </i>. </span><span class="copyright">Copyright © 1998 ISO. </span></p></div><div class="biblioentry"><a id="id514997"></a><p><span class="title"><i> - ISO/IEC 9899:1999 Programming languages - C - </i>. </span><span class="copyright">Copyright © 1999 ISO. </span></p></div><div class="biblioentry"><a id="id515015"></a><p><span class="title"><i> - System Interface Definitions, Issue 6 (IEEE Std. 1003.1-200x) - </i>. </span><span class="copyright">Copyright © 1999 - The Open Group/The Institute of Electrical and Electronics Engineers, Inc.. </span><span class="biblioid"> - <a class="ulink" href="http://www.opennc.org/austin/docreg.html" target="_top"> - </a> - . </span></p></div><div class="biblioentry"><a id="id427733"></a><p><span class="title"><i> - The C++ Programming Language, Special Edition - </i>. </span><span class="author"><span class="firstname">Bjarne</span> <span class="surname">Stroustrup</span>. </span><span class="copyright">Copyright © 2000 Addison Wesley, Inc.. </span><span class="pagenums">Appendix D. </span><span class="publisher"><span class="publishername"> - Addison Wesley - . </span></span></p></div><div class="biblioentry"><a id="id427774"></a><p><span class="title"><i> - Standard C++ IOStreams and Locales - </i>. </span><span class="subtitle"> - Advanced Programmer's Guide and Reference - . </span><span class="author"><span class="firstname">Angelika</span> <span class="surname">Langer</span>. </span><span class="author"><span class="firstname">Klaus</span> <span class="surname">Kreft</span>. </span><span class="copyright">Copyright © 2000 Addison Wesley Longman, Inc.. </span><span class="publisher"><span class="publishername"> - Addison Wesley Longman - . </span></span></p></div><div class="biblioentry"><a id="id402618"></a><p><span class="title"><i> - Java 2 Platform, Standard Edition, v 1.3.1 API Specification - </i>. </span><span class="pagenums">java.util.Properties, java.text.MessageFormat, -java.util.Locale, java.util.ResourceBundle. </span><span class="biblioid"> - <a class="ulink" href="http://java.sun.com/j2se/1.3/docs/api" target="_top"> - </a> - . </span></p></div><div class="biblioentry"><a id="id404627"></a><p><span class="title"><i> - GNU gettext tools, version 0.10.38, Native Language Support -Library and Tools. - </i>. </span><span class="biblioid"> - <a class="ulink" href="http://sources.redhat.com/gettext" target="_top"> - </a> - . </span></p></div></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="codecvt.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="facets.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="containers.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">codecvt </td><td width="20%" align="center"><a accesskey="h" href="../spine.html">Home</a></td><td width="40%" align="right" valign="top"> Part VII. - Containers - -</td></tr></table></div></body></html> |