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   Localization
   <a id="id-1.3.4.6.1.1.1" class="indexterm"></a>
 </h2></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="section"><a href="localization.html#std.localization.locales">Locales</a></span></dt><dd><dl><dt><span class="section"><a href="localization.html#std.localization.locales.locale">locale</a></span></dt><dd><dl><dt><span class="section"><a href="localization.html#locales.locale.req">Requirements</a></span></dt><dt><span class="section"><a href="localization.html#locales.locale.design">Design</a></span></dt><dt><span class="section"><a href="localization.html#locales.locale.impl">Implementation</a></span></dt><dd><dl><dt><span class="section"><a href="localization.html#locale.impl.c">Interacting with "C" locales</a></span></dt></dl></dd><dt><span class="section"><a href="localization.html#locales.locale.future">Future</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="facets.html">Facets</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#std.localization.facet.ctype">ctype</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#facet.ctype.impl">Implementation</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#facet.ctype.impl.spec">Specializations</a></span></dt></dl></dd><dt><span class="section"><a href="facets.html#facet.ctype.future">Future</a></span></dt></dl></dd><dt><span class="section"><a href="facets.html#std.localization.facet.codecvt">codecvt</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#facet.codecvt.req">Requirements</a></span></dt><dt><span class="section"><a href="facets.html#facet.codecvt.design">Design</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#codecvt.design.wchar_t_size"><span class="type">wchar_t</span> Size</a></span></dt><dt><span class="section"><a href="facets.html#codecvt.design.unicode">Support for Unicode</a></span></dt><dt><span class="section"><a href="facets.html#codecvt.design.issues">Other Issues</a></span></dt></dl></dd><dt><span class="section"><a href="facets.html#facet.codecvt.impl">Implementation</a></span></dt><dt><span class="section"><a href="facets.html#facet.codecvt.use">Use</a></span></dt><dt><span class="section"><a href="facets.html#facet.codecvt.future">Future</a></span></dt></dl></dd><dt><span class="section"><a href="facets.html#std.localization.facet.messages">messages</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#facet.messages.req">Requirements</a></span></dt><dt><span class="section"><a href="facets.html#facet.messages.design">Design</a></span></dt><dt><span class="section"><a href="facets.html#facet.messages.impl">Implementation</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#messages.impl.models">Models</a></span></dt><dt><span class="section"><a href="facets.html#messages.impl.gnu">The GNU Model</a></span></dt></dl></dd><dt><span class="section"><a href="facets.html#facet.messages.use">Use</a></span></dt><dt><span class="section"><a href="facets.html#facet.messages.future">Future</a></span></dt></dl></dd></dl></dd></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="std.localization.locales"></a>Locales</h2></div></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="std.localization.locales.locale"></a>locale</h3></div></div></div><p>
 Describes the basic locale object, including nested
 classes id, facet, and the reference-counted implementation object,
 class _Impl.
 </p><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="locales.locale.req"></a>Requirements</h4></div></div></div><p>
 Class locale is non-templatized and has two distinct types nested
 inside of it:
 </p><div class="blockquote"><blockquote class="blockquote"><p>
 <span class="emphasis"><em>
 class facet
 22.1.1.1.2 Class locale::facet
 </em></span>
 </p></blockquote></div><p>
 Facets actually implement locale functionality. For instance, a facet
 called numpunct is the data object that can be used to query for the
 thousands separator in the locale.
 </p><p>
 Literally, a facet is strictly defined:
 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
       Containing the following public data member:
     </p><p>
       <code class="code">static locale::id id;</code>
     </p></li><li class="listitem"><p>
       Derived from another facet:
     </p><p>
       <code class="code">class gnu_codecvt: public std::ctype&lt;user-defined-type&gt;</code>
     </p></li></ul></div><p>
 Of interest in this class are the memory management options explicitly
 specified as an argument to facet's constructor. Each constructor of a
 facet class takes a std::size_t __refs argument: if __refs == 0, the
 facet is deleted when the locale containing it is destroyed. If __refs
 == 1, the facet is not destroyed, even when it is no longer
 referenced.
 </p><div class="blockquote"><blockquote class="blockquote"><p>
 <span class="emphasis"><em>
 class id
 22.1.1.1.3 - Class locale::id
 </em></span>
 </p></blockquote></div><p>
 Provides an index for looking up specific facets.
 </p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="locales.locale.design"></a>Design</h4></div></div></div><p>
 The major design challenge is fitting an object-orientated and
 non-global locale design on top of POSIX and other relevant standards,
 which include the Single Unix (nee X/Open.)
 </p><p>
 Because C and earlier versions of POSIX fall down so completely,
 portability is an issue.
 </p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="locales.locale.impl"></a>Implementation</h4></div></div></div><div class="section"><div class="titlepage"><div><div><h5 class="title"><a id="locale.impl.c"></a>Interacting with "C" locales</h5></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
        <code class="code">locale -a</code> displays available locales.
      </p><div class="blockquote"><blockquote class="blockquote"><pre class="programlisting">
 af_ZA
 ar_AE
 ar_AE.utf8
 ar_BH
 ar_BH.utf8
 ar_DZ
 ar_DZ.utf8
 ar_EG
 ar_EG.utf8
 ar_IN
 ar_IQ
 ar_IQ.utf8
 ar_JO
 ar_JO.utf8
 ar_KW
 ar_KW.utf8
 ar_LB
 ar_LB.utf8
 ar_LY
 ar_LY.utf8
 ar_MA
 ar_MA.utf8
 ar_OM
 ar_OM.utf8
 ar_QA
 ar_QA.utf8
 ar_SA
 ar_SA.utf8
 ar_SD
 ar_SD.utf8
 ar_SY
 ar_SY.utf8
 ar_TN
 ar_TN.utf8
 ar_YE
 ar_YE.utf8
 be_BY
 be_BY.utf8
 bg_BG
 bg_BG.utf8
 br_FR
 bs_BA
 C
 ca_ES
 ca_ES@euro
 ca_ES.utf8
 ca_ES.utf8@euro
 cs_CZ
 cs_CZ.utf8
 cy_GB
 da_DK
 da_DK.iso885915
 da_DK.utf8
 de_AT
 de_AT@euro
 de_AT.utf8
 de_AT.utf8@euro
 de_BE
 de_BE@euro
 de_BE.utf8
 de_BE.utf8@euro
 de_CH
 de_CH.utf8
 de_DE
 de_DE@euro
 de_DE.utf8
 de_DE.utf8@euro
 de_LU
 de_LU@euro
 de_LU.utf8
 de_LU.utf8@euro
 el_GR
 el_GR.utf8
 en_AU
 en_AU.utf8
 en_BW
 en_BW.utf8
 en_CA
 en_CA.utf8
 en_DK
 en_DK.utf8
 en_GB
 en_GB.iso885915
 en_GB.utf8
 en_HK
 en_HK.utf8
 en_IE
 en_IE@euro
 en_IE.utf8
 en_IE.utf8@euro
 en_IN
 en_NZ
 en_NZ.utf8
 en_PH
 en_PH.utf8
 en_SG
 en_SG.utf8
 en_US
 en_US.iso885915
 en_US.utf8
 en_ZA
 en_ZA.utf8
 en_ZW
 en_ZW.utf8
 es_AR
 es_AR.utf8
 es_BO
 es_BO.utf8
 es_CL
 es_CL.utf8
 es_CO
 es_CO.utf8
 es_CR
 es_CR.utf8
 es_DO
 es_DO.utf8
 es_EC
 es_EC.utf8
 es_ES
 es_ES@euro
 es_ES.utf8
 es_ES.utf8@euro
 es_GT
 es_GT.utf8
 es_HN
 es_HN.utf8
 es_MX
 es_MX.utf8
 es_NI
 es_NI.utf8
 es_PA
 es_PA.utf8
 es_PE
 es_PE.utf8
 es_PR
 es_PR.utf8
 es_PY
 es_PY.utf8
 es_SV
 es_SV.utf8
 es_US
 es_US.utf8
 es_UY
 es_UY.utf8
 es_VE
 es_VE.utf8
 et_EE
 et_EE.utf8
 eu_ES
 eu_ES@euro
 eu_ES.utf8
 eu_ES.utf8@euro
 fa_IR
 fi_FI
 fi_FI@euro
 fi_FI.utf8
 fi_FI.utf8@euro
 fo_FO
 fo_FO.utf8
 fr_BE
 fr_BE@euro
 fr_BE.utf8
 fr_BE.utf8@euro
 fr_CA
 fr_CA.utf8
 fr_CH
 fr_CH.utf8
 fr_FR
 fr_FR@euro
 fr_FR.utf8
 fr_FR.utf8@euro
 fr_LU
 fr_LU@euro
 fr_LU.utf8
 fr_LU.utf8@euro
 ga_IE
 ga_IE@euro
 ga_IE.utf8
 ga_IE.utf8@euro
 gl_ES
 gl_ES@euro
 gl_ES.utf8
 gl_ES.utf8@euro
 gv_GB
 gv_GB.utf8
 he_IL
 he_IL.utf8
 hi_IN
 hr_HR
 hr_HR.utf8
 hu_HU
 hu_HU.utf8
 id_ID
 id_ID.utf8
 is_IS
 is_IS.utf8
 it_CH
 it_CH.utf8
 it_IT
 it_IT@euro
 it_IT.utf8
 it_IT.utf8@euro
 iw_IL
 iw_IL.utf8
 ja_JP.eucjp
 ja_JP.utf8
 ka_GE
 kl_GL
 kl_GL.utf8
 ko_KR.euckr
 ko_KR.utf8
 kw_GB
 kw_GB.utf8
 lt_LT
 lt_LT.utf8
 lv_LV
 lv_LV.utf8
 mi_NZ
 mk_MK
 mk_MK.utf8
 mr_IN
 ms_MY
 ms_MY.utf8
 mt_MT
 mt_MT.utf8
 nl_BE
 nl_BE@euro
 nl_BE.utf8
 nl_BE.utf8@euro
 nl_NL
 nl_NL@euro
 nl_NL.utf8
 nl_NL.utf8@euro
 nn_NO
 nn_NO.utf8
 no_NO
 no_NO.utf8
 oc_FR
 pl_PL
 pl_PL.utf8
 POSIX
 pt_BR
 pt_BR.utf8
 pt_PT
 pt_PT@euro
 pt_PT.utf8
 pt_PT.utf8@euro
 ro_RO
 ro_RO.utf8
 ru_RU
 ru_RU.koi8r
 ru_RU.utf8
 ru_UA
 ru_UA.utf8
 se_NO
 sk_SK
 sk_SK.utf8
 sl_SI
 sl_SI.utf8
 sq_AL
 sq_AL.utf8
 sr_YU
 sr_YU@cyrillic
 sr_YU.utf8
 sr_YU.utf8@cyrillic
 sv_FI
 sv_FI@euro
 sv_FI.utf8
 sv_FI.utf8@euro
 sv_SE
 sv_SE.iso885915
 sv_SE.utf8
 ta_IN
 te_IN
 tg_TJ
 th_TH
 th_TH.utf8
 tl_PH
 tr_TR
 tr_TR.utf8
 uk_UA
 uk_UA.utf8
 ur_PK
 uz_UZ
 vi_VN
 vi_VN.tcvn
 wa_BE
 wa_BE@euro
 yi_US
 zh_CN
 zh_CN.gb18030
 zh_CN.gbk
 zh_CN.utf8
 zh_HK
 zh_HK.utf8
 zh_TW
 zh_TW.euctw
 zh_TW.utf8
 </pre></blockquote></div></li><li class="listitem"><p>
        <code class="code">`locale`</code> displays environmental variables that
        impact how locale("") will be deduced.
      </p><div class="blockquote"><blockquote class="blockquote"><pre class="programlisting">
 LANG=en_US
 LC_CTYPE="en_US"
 LC_NUMERIC="en_US"
 LC_TIME="en_US"
 LC_COLLATE="en_US"
 LC_MONETARY="en_US"
 LC_MESSAGES="en_US"
 LC_PAPER="en_US"
 LC_NAME="en_US"
 LC_ADDRESS="en_US"
 LC_TELEPHONE="en_US"
 LC_MEASUREMENT="en_US"
 LC_IDENTIFICATION="en_US"
 LC_ALL=
 </pre></blockquote></div></li></ul></div><p>
 From Josuttis, p. 697-698, which says, that "there is only *one*
 relation (of the C++ locale mechanism) to the C locale mechanism: the
 global C locale is modified if a named C++ locale object is set as the
 global locale" (emphasis Paolo), that is:
 </p><pre class="programlisting">std::locale::global(std::locale(""));</pre><p>affects the C functions as if the following call was made:</p><pre class="programlisting">std::setlocale(LC_ALL, "");</pre><p>
   On the other hand, there is *no* vice versa, that is, calling
   setlocale has *no* whatsoever on the C++ locale mechanism, in
   particular on the working of locale(""), which constructs the locale
   object from the environment of the running program, that is, in
   practice, the set of LC_ALL, LANG, etc. variable of the shell.
 </p></div></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="locales.locale.future"></a>Future</h4></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
        Locale initialization: at what point does _S_classic, _S_global
        get initialized? Can named locales assume this initialization
        has already taken place?
      </p></li><li class="listitem"><p>
        Document how named locales error check when filling data
        members. I.e., a fr_FR locale that doesn't have
        numpunct::truename(): does it use "true"? Or is it a blank
        string? What's the convention?
    </p></li><li class="listitem"><p>
        Explain how locale aliasing happens. When does "de_DE" use "de"
        information? What is the rule for locales composed of just an
        ISO language code (say, "de") and locales with both an ISO
        language code and ISO country code (say, "de_DE").
      </p></li><li class="listitem"><p>
        What should non-required facet instantiations do?  If the
        generic implementation is provided, then how to end-users
        provide specializations?
    </p></li></ul></div></div><div class="bibliography"><div class="titlepage"><div><div><h4 class="title"><a id="locales.locale.biblio"></a>Bibliography</h4></div></div></div><div class="biblioentry"><a id="id-1.3.4.6.2.2.7.2"></a><p><span class="citetitle"><em class="citetitle">
       The GNU C Library
     </em>. </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="id-1.3.4.6.2.2.7.3"></a><p><span class="citetitle"><em class="citetitle">
       Correspondence
     </em>. </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="id-1.3.4.6.2.2.7.4"></a><p><span class="citetitle"><em class="citetitle">
       ISO/IEC 14882:1998 Programming languages - C++
     </em>. </span><span class="copyright">Copyright © 1998 ISO. </span></p></div><div class="biblioentry"><a id="id-1.3.4.6.2.2.7.5"></a><p><span class="citetitle"><em class="citetitle">
       ISO/IEC 9899:1999 Programming languages - C
     </em>. </span><span class="copyright">Copyright © 1999 ISO. </span></p></div><div class="biblioentry"><a id="id-1.3.4.6.2.2.7.6"></a><p><span class="title"><em>
 	<a class="link" href="https://pubs.opengroup.org/onlinepubs/9699919799/" target="_top">
       System Interface Definitions, Issue 7 (IEEE Std. 1003.1-2008)
 	</a>
       </em>. </span><span class="copyright">Copyright © 2008
 	The Open Group/The Institute of Electrical and Electronics
 	Engineers, Inc.
       . </span></p></div><div class="biblioentry"><a id="id-1.3.4.6.2.2.7.7"></a><p><span class="citetitle"><em class="citetitle">
       The C++ Programming Language, Special Edition
     </em>. </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="id-1.3.4.6.2.2.7.8"></a><p><span class="citetitle"><em class="citetitle">
       Standard C++ IOStreams and Locales
     </em>. </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></div></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="strings.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="std_contents.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="facets.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 7.
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	Localization
	<a id="id-1.3.4.6.1.1.1" class="indexterm"></a>
	</h2></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="section"><a href="localization.html#std.localization.locales">Locales</a></span></dt><dd><dl><dt><span class="section"><a href="localization.html#std.localization.locales.locale">locale</a></span></dt><dd><dl><dt><span class="section"><a href="localization.html#locales.locale.req">Requirements</a></span></dt><dt><span class="section"><a href="localization.html#locales.locale.design">Design</a></span></dt><dt><span class="section"><a href="localization.html#locales.locale.impl">Implementation</a></span></dt><dd><dl><dt><span class="section"><a href="localization.html#locale.impl.c">Interacting with "C" locales</a></span></dt></dl></dd><dt><span class="section"><a href="localization.html#locales.locale.future">Future</a></span></dt></dl></dd></dl></dd><dt><span class="section"><a href="facets.html">Facets</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#std.localization.facet.ctype">ctype</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#facet.ctype.impl">Implementation</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#facet.ctype.impl.spec">Specializations</a></span></dt></dl></dd><dt><span class="section"><a href="facets.html#facet.ctype.future">Future</a></span></dt></dl></dd><dt><span class="section"><a href="facets.html#std.localization.facet.codecvt">codecvt</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#facet.codecvt.req">Requirements</a></span></dt><dt><span class="section"><a href="facets.html#facet.codecvt.design">Design</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#codecvt.design.wchar_t_size"><span class="type">wchar_t</span> Size</a></span></dt><dt><span class="section"><a href="facets.html#codecvt.design.unicode">Support for Unicode</a></span></dt><dt><span class="section"><a href="facets.html#codecvt.design.issues">Other Issues</a></span></dt></dl></dd><dt><span class="section"><a href="facets.html#facet.codecvt.impl">Implementation</a></span></dt><dt><span class="section"><a href="facets.html#facet.codecvt.use">Use</a></span></dt><dt><span class="section"><a href="facets.html#facet.codecvt.future">Future</a></span></dt></dl></dd><dt><span class="section"><a href="facets.html#std.localization.facet.messages">messages</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#facet.messages.req">Requirements</a></span></dt><dt><span class="section"><a href="facets.html#facet.messages.design">Design</a></span></dt><dt><span class="section"><a href="facets.html#facet.messages.impl">Implementation</a></span></dt><dd><dl><dt><span class="section"><a href="facets.html#messages.impl.models">Models</a></span></dt><dt><span class="section"><a href="facets.html#messages.impl.gnu">The GNU Model</a></span></dt></dl></dd><dt><span class="section"><a href="facets.html#facet.messages.use">Use</a></span></dt><dt><span class="section"><a href="facets.html#facet.messages.future">Future</a></span></dt></dl></dd></dl></dd></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="std.localization.locales"></a>Locales</h2></div></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="std.localization.locales.locale"></a>locale</h3></div></div></div><p>
	Describes the basic locale object, including nested
	classes id, facet, and the reference-counted implementation object,
	class _Impl.
	</p><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="locales.locale.req"></a>Requirements</h4></div></div></div><p>
	Class locale is non-templatized and has two distinct types nested
	inside of it:
	</p><div class="blockquote"><blockquote class="blockquote"><p>
	<span class="emphasis"><em>
	class facet
	22.1.1.1.2 Class locale::facet
	</em></span>
	</p></blockquote></div><p>
	Facets actually implement locale functionality. For instance, a facet
	called numpunct is the data object that can be used to query for the
	thousands separator in the locale.
	</p><p>
	Literally, a facet is strictly defined:
	</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
	Containing the following public data member:
	</p><p>
	<code class="code">static locale::id id;</code>
	</p></li><li class="listitem"><p>
	Derived from another facet:
	</p><p>
	<code class="code">class gnu_codecvt: public std::ctype<user-defined-type></code>
	</p></li></ul></div><p>
	Of interest in this class are the memory management options explicitly
	specified as an argument to facet's constructor. Each constructor of a
	facet class takes a std::size_t __refs argument: if __refs == 0, the
	facet is deleted when the locale containing it is destroyed. If __refs
	== 1, the facet is not destroyed, even when it is no longer
	referenced.
	</p><div class="blockquote"><blockquote class="blockquote"><p>
	<span class="emphasis"><em>
	class id
	22.1.1.1.3 - Class locale::id
	</em></span>
	</p></blockquote></div><p>
	Provides an index for looking up specific facets.
	</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="locales.locale.design"></a>Design</h4></div></div></div><p>
	The major design challenge is fitting an object-orientated and
	non-global locale design on top of POSIX and other relevant standards,
	which include the Single Unix (nee X/Open.)
	</p><p>
	Because C and earlier versions of POSIX fall down so completely,
	portability is an issue.
	</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="locales.locale.impl"></a>Implementation</h4></div></div></div><div class="section"><div class="titlepage"><div><div><h5 class="title"><a id="locale.impl.c"></a>Interacting with "C" locales</h5></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
	<code class="code">locale -a</code> displays available locales.
	</p><div class="blockquote"><blockquote class="blockquote"><pre class="programlisting">
	af_ZA
	ar_AE
	ar_AE.utf8
	ar_BH
	ar_BH.utf8
	ar_DZ
	ar_DZ.utf8
	ar_EG
	ar_EG.utf8
	ar_IN
	ar_IQ
	ar_IQ.utf8
	ar_JO
	ar_JO.utf8
	ar_KW
	ar_KW.utf8
	ar_LB
	ar_LB.utf8
	ar_LY
	ar_LY.utf8
	ar_MA
	ar_MA.utf8
	ar_OM
	ar_OM.utf8
	ar_QA
	ar_QA.utf8
	ar_SA
	ar_SA.utf8
	ar_SD
	ar_SD.utf8
	ar_SY
	ar_SY.utf8
	ar_TN
	ar_TN.utf8
	ar_YE
	ar_YE.utf8
	be_BY
	be_BY.utf8
	bg_BG
	bg_BG.utf8
	br_FR
	bs_BA
	C
	ca_ES
	ca_ES@euro
	ca_ES.utf8
	ca_ES.utf8@euro
	cs_CZ
	cs_CZ.utf8
	cy_GB
	da_DK
	da_DK.iso885915
	da_DK.utf8
	de_AT
	de_AT@euro
	de_AT.utf8
	de_AT.utf8@euro
	de_BE
	de_BE@euro
	de_BE.utf8
	de_BE.utf8@euro
	de_CH
	de_CH.utf8
	de_DE
	de_DE@euro
	de_DE.utf8
	de_DE.utf8@euro
	de_LU
	de_LU@euro
	de_LU.utf8
	de_LU.utf8@euro
	el_GR
	el_GR.utf8
	en_AU
	en_AU.utf8
	en_BW
	en_BW.utf8
	en_CA
	en_CA.utf8
	en_DK
	en_DK.utf8
	en_GB
	en_GB.iso885915
	en_GB.utf8
	en_HK
	en_HK.utf8
	en_IE
	en_IE@euro
	en_IE.utf8
	en_IE.utf8@euro
	en_IN
	en_NZ
	en_NZ.utf8
	en_PH
	en_PH.utf8
	en_SG
	en_SG.utf8
	en_US
	en_US.iso885915
	en_US.utf8
	en_ZA
	en_ZA.utf8
	en_ZW
	en_ZW.utf8
	es_AR
	es_AR.utf8
	es_BO
	es_BO.utf8
	es_CL
	es_CL.utf8
	es_CO
	es_CO.utf8
	es_CR
	es_CR.utf8
	es_DO
	es_DO.utf8
	es_EC
	es_EC.utf8
	es_ES
	es_ES@euro
	es_ES.utf8
	es_ES.utf8@euro
	es_GT
	es_GT.utf8
	es_HN
	es_HN.utf8
	es_MX
	es_MX.utf8
	es_NI
	es_NI.utf8
	es_PA
	es_PA.utf8
	es_PE
	es_PE.utf8
	es_PR
	es_PR.utf8
	es_PY
	es_PY.utf8
	es_SV
	es_SV.utf8
	es_US
	es_US.utf8
	es_UY
	es_UY.utf8
	es_VE
	es_VE.utf8
	et_EE
	et_EE.utf8
	eu_ES
	eu_ES@euro
	eu_ES.utf8
	eu_ES.utf8@euro
	fa_IR
	fi_FI
	fi_FI@euro
	fi_FI.utf8
	fi_FI.utf8@euro
	fo_FO
	fo_FO.utf8
	fr_BE
	fr_BE@euro
	fr_BE.utf8
	fr_BE.utf8@euro
	fr_CA
	fr_CA.utf8
	fr_CH
	fr_CH.utf8
	fr_FR
	fr_FR@euro
	fr_FR.utf8
	fr_FR.utf8@euro
	fr_LU
	fr_LU@euro
	fr_LU.utf8
	fr_LU.utf8@euro
	ga_IE
	ga_IE@euro
	ga_IE.utf8
	ga_IE.utf8@euro
	gl_ES
	gl_ES@euro
	gl_ES.utf8
	gl_ES.utf8@euro
	gv_GB
	gv_GB.utf8
	he_IL
	he_IL.utf8
	hi_IN
	hr_HR
	hr_HR.utf8
	hu_HU
	hu_HU.utf8
	id_ID
	id_ID.utf8
	is_IS
	is_IS.utf8
	it_CH
	it_CH.utf8
	it_IT
	it_IT@euro
	it_IT.utf8
	it_IT.utf8@euro
	iw_IL
	iw_IL.utf8
	ja_JP.eucjp
	ja_JP.utf8
	ka_GE
	kl_GL
	kl_GL.utf8
	ko_KR.euckr
	ko_KR.utf8
	kw_GB
	kw_GB.utf8
	lt_LT
	lt_LT.utf8
	lv_LV
	lv_LV.utf8
	mi_NZ
	mk_MK
	mk_MK.utf8
	mr_IN
	ms_MY
	ms_MY.utf8
	mt_MT
	mt_MT.utf8
	nl_BE
	nl_BE@euro
	nl_BE.utf8
	nl_BE.utf8@euro
	nl_NL
	nl_NL@euro
	nl_NL.utf8
	nl_NL.utf8@euro
	nn_NO
	nn_NO.utf8
	no_NO
	no_NO.utf8
	oc_FR
	pl_PL
	pl_PL.utf8
	POSIX
	pt_BR
	pt_BR.utf8
	pt_PT
	pt_PT@euro
	pt_PT.utf8
	pt_PT.utf8@euro
	ro_RO
	ro_RO.utf8
	ru_RU
	ru_RU.koi8r
	ru_RU.utf8
	ru_UA
	ru_UA.utf8
	se_NO
	sk_SK
	sk_SK.utf8
	sl_SI
	sl_SI.utf8
	sq_AL
	sq_AL.utf8
	sr_YU
	sr_YU@cyrillic
	sr_YU.utf8
	sr_YU.utf8@cyrillic
	sv_FI
	sv_FI@euro
	sv_FI.utf8
	sv_FI.utf8@euro
	sv_SE
	sv_SE.iso885915
	sv_SE.utf8
	ta_IN
	te_IN
	tg_TJ
	th_TH
	th_TH.utf8
	tl_PH
	tr_TR
	tr_TR.utf8
	uk_UA
	uk_UA.utf8
	ur_PK
	uz_UZ
	vi_VN
	vi_VN.tcvn
	wa_BE
	wa_BE@euro
	yi_US
	zh_CN
	zh_CN.gb18030
	zh_CN.gbk
	zh_CN.utf8
	zh_HK
	zh_HK.utf8
	zh_TW
	zh_TW.euctw
	zh_TW.utf8
	</pre></blockquote></div></li><li class="listitem"><p>
	<code class="code">`locale`</code> displays environmental variables that
	impact how locale("") will be deduced.
	</p><div class="blockquote"><blockquote class="blockquote"><pre class="programlisting">
	LANG=en_US
	LC_CTYPE="en_US"
	LC_NUMERIC="en_US"
	LC_TIME="en_US"
	LC_COLLATE="en_US"
	LC_MONETARY="en_US"
	LC_MESSAGES="en_US"
	LC_PAPER="en_US"
	LC_NAME="en_US"
	LC_ADDRESS="en_US"
	LC_TELEPHONE="en_US"
	LC_MEASUREMENT="en_US"
	LC_IDENTIFICATION="en_US"
	LC_ALL=
	</pre></blockquote></div></li></ul></div><p>
	From Josuttis, p. 697-698, which says, that "there is only one
	relation (of the C++ locale mechanism) to the C locale mechanism: the
	global C locale is modified if a named C++ locale object is set as the
	global locale" (emphasis Paolo), that is:
	</p><pre class="programlisting">std::locale::global(std::locale(""));</pre><p>affects the C functions as if the following call was made:</p><pre class="programlisting">std::setlocale(LC_ALL, "");</pre><p>
	On the other hand, there is no vice versa, that is, calling
	setlocale has no whatsoever on the C++ locale mechanism, in
	particular on the working of locale(""), which constructs the locale
	object from the environment of the running program, that is, in
	practice, the set of LC_ALL, LANG, etc. variable of the shell.
	</p></div></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="locales.locale.future"></a>Future</h4></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
	Locale initialization: at what point does _S_classic, _S_global
	get initialized? Can named locales assume this initialization
	has already taken place?
	</p></li><li class="listitem"><p>
	Document how named locales error check when filling data
	members. I.e., a fr_FR locale that doesn't have
	numpunct::truename(): does it use "true"? Or is it a blank
	string? What's the convention?
	</p></li><li class="listitem"><p>
	Explain how locale aliasing happens. When does "de_DE" use "de"
	information? What is the rule for locales composed of just an
	ISO language code (say, "de") and locales with both an ISO
	language code and ISO country code (say, "de_DE").
	</p></li><li class="listitem"><p>
	What should non-required facet instantiations do? If the
	generic implementation is provided, then how to end-users
	provide specializations?
	</p></li></ul></div></div><div class="bibliography"><div class="titlepage"><div><div><h4 class="title"><a id="locales.locale.biblio"></a>Bibliography</h4></div></div></div><div class="biblioentry"><a id="id-1.3.4.6.2.2.7.2"></a><p><span class="citetitle"><em class="citetitle">
	The GNU C Library
	</em>. </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="id-1.3.4.6.2.2.7.3"></a><p><span class="citetitle"><em class="citetitle">
	Correspondence
	</em>. </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="id-1.3.4.6.2.2.7.4"></a><p><span class="citetitle"><em class="citetitle">
	ISO/IEC 14882:1998 Programming languages - C++
	</em>. </span><span class="copyright">Copyright © 1998 ISO. </span></p></div><div class="biblioentry"><a id="id-1.3.4.6.2.2.7.5"></a><p><span class="citetitle"><em class="citetitle">
	ISO/IEC 9899:1999 Programming languages - C
	</em>. </span><span class="copyright">Copyright © 1999 ISO. </span></p></div><div class="biblioentry"><a id="id-1.3.4.6.2.2.7.6"></a><p><span class="title"><em>
	<a class="link" href="https://pubs.opengroup.org/onlinepubs/9699919799/" target="_top">
	System Interface Definitions, Issue 7 (IEEE Std. 1003.1-2008)
	</a>
	</em>. </span><span class="copyright">Copyright © 2008
	The Open Group/The Institute of Electrical and Electronics
	Engineers, Inc.
	. </span></p></div><div class="biblioentry"><a id="id-1.3.4.6.2.2.7.7"></a><p><span class="citetitle"><em class="citetitle">
	The C++ Programming Language, Special Edition
	</em>. </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="id-1.3.4.6.2.2.7.8"></a><p><span class="citetitle"><em class="citetitle">
	Standard C++ IOStreams and Locales
	</em>. </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></div></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="strings.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="std_contents.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="facets.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 7.
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