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| <html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>Internationalization</title><link rel="stylesheet" type="text/css" href="docbook.css"><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot"><link rel="home" href="cygwin-ug-net.html" title="Cygwin User's Guide"><link rel="up" href="setup-net.html" title="Chapter 2. Setting Up Cygwin"><link rel="prev" href="setup-maxmem.html" title="Changing Cygwin's Maximum Memory"><link rel="next" href="setup-files.html" title="Customizing bash"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Internationalization</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="setup-maxmem.html">Prev</a> </td><th width="60%" align="center">Chapter 2. Setting Up Cygwin</th><td width="20%" align="right"> <a accesskey="n" href="setup-files.html">Next</a></td></tr></table><hr></div><div class="sect1"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="setup-locale"></a>Internationalization</h2></div></div></div><div class="sect2"><div class="titlepage"><div><div><h3 class="title"><a name="setup-locale-ov"></a>Overview</h3></div></div></div><p> |
| Internationalization support is controlled by the <code class="envar">LANG</code> and |
| <code class="envar">LC_xxx</code> environment variables. You can set all of them |
| but Cygwin itself only honors the variables <code class="envar">LC_ALL</code>, |
| <code class="envar">LC_CTYPE</code>, and <code class="envar">LANG</code>, in this order, according |
| to the POSIX standard. The content of these variables should follow the |
| POSIX standard for a locale specifier. The correct form of a locale |
| specifier is</p><pre class="screen"> |
| language[[_TERRITORY][.charset][@modifier]] |
| </pre><p>"language" is a lowercase two character string per ISO 639-1, or, |
| if there is no ISO 639-1 code for the language (for instance, "Lower Sorbian"), |
| a three character string per ISO 639-3.</p><p>"TERRITORY" is an uppercase two character string per ISO 3166, charset is |
| one of a list of supported character sets. The modifier doesn't matter |
| here (though some are recognized, see below). If you're interested in the |
| exact description, you can find it in the online publication of the POSIX |
| manual pages on the homepage of the |
| <a class="ulink" href="http://www.opengroup.org/" target="_top">Open Group</a>.</p><p>Typical locale specifiers are</p><pre class="screen"> |
| "de_CH" language = German, territory = Switzerland, default charset |
| "fr_FR.UTF-8" language = french, territory = France, charset = UTF-8 |
| "ko_KR.eucKR" language = korean, territory = South Korea, charset = eucKR |
| "syr_SY" language = Syriac, territory = Syria, default charset |
| </pre><p> |
| If the locale specifier does not follow the above form, Cygwin checks |
| if the locale is one of the locale aliases defined in the file |
| <code class="filename">/usr/share/locale/locale.alias</code>. If so, and if |
| the replacement localename is supported by the underlying Windows, |
| the locale is accepted, too. So, given the default content of the |
| <code class="filename">/usr/share/locale/locale.alias</code> file, the below |
| examples would be valid locale specifiers as well. |
| </p><pre class="screen"> |
| "catalan" defined as "ca_ES.ISO-8859-1" in locale.alias |
| "japanese" defined as "ja_JP.eucJP" in locale.alias |
| "turkish" defined as "tr_TR.ISO-8859-9" in locale.alias |
| </pre><p>The file <code class="filename">/usr/share/locale/locale.alias</code> is |
| provided by the gettext package under Cygwin.</p><p> |
| At application startup, the application's locale is set to the default |
| "C" or "POSIX" locale. This locale defaults to the ASCII character set |
| on the application level. If you want to stick to the "C" locale and only |
| change to another charset, you can define this by setting one of the locale |
| environment variables to "C.charset". For instance</p><pre class="screen"> |
| "C.ISO-8859-1" |
| </pre><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>The default locale in the absence of the aforementioned locale |
| environment variables is "C.UTF-8".</p></div><p>Windows uses the UTF-16 charset exclusively to store the names |
| of any object used by the Operating System. This is especially important |
| with filenames. Cygwin uses the setting of the locale environment variables |
| <code class="envar">LC_ALL</code>, <code class="envar">LC_CTYPE</code>, and <code class="envar">LANG</code>, to |
| determine how to convert Windows filenames from their UTF-16 representation |
| to the singlebyte or multibyte character set used by Cygwin.</p><p> |
| The setting of the locale environment variables at process startup |
| is effective for Cygwin's internal conversions to and from the Windows UTF-16 |
| object names for the entire lifetime of the current process. Changing |
| the environment variables to another value changes the way filenames are |
| converted in subsequently started child processes, but not within the same |
| process.</p><p> |
| However, even if one of the locale environment variables is set to |
| some other value than "C", this does <span class="emphasis"><em>only</em></span> affect |
| how Cygwin itself converts filenames. As the POSIX standard requires, |
| it's the application's responsibility to activate that locale for its |
| own purposes, typically by using the call</p><pre class="screen"> |
| setlocale (LC_ALL, ""); |
| </pre><p>early in the application code. Again, so that this doesn't get |
| lost: If the application calls setlocale as above, and there is none |
| of the important locale variables set in the environment, the locale |
| is set to the default locale, which is "C.UTF-8".</p><p>But what about applications which are not locale-aware? Per POSIX, |
| they are running in the "C" or "POSIX" locale, which implies the ASCII |
| charset. The Cygwin DLL itself, however, will nevertheless use the locale |
| set in the environment (or the "C.UTF-8" default locale) for converting |
| filenames etc.</p><p>When the locale in the environment specifies an ASCII charset, |
| for example "C" or "en_US.ASCII", Cygwin will still use UTF-8 |
| under the hood to translate filenames. This allows for easier |
| interoperability with applications running in the default "C.UTF-8" locale. |
| </p><p> |
| The language and territory are used to fetch locale-dependent information |
| from Windows. If the language and territory are not known to Windows, the |
| <code class="function">setlocale</code> function fails.</p><p>The following modifiers are recognized. Any other modifier is simply |
| ignored for now.</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: bullet; "><li class="listitem" style="list-style-type: disc"><p> |
| For locales which use the Euro (EUR) as currency, the modifier "@euro" |
| can be added to enforce usage of the ISO-8859-15 character set, which |
| includes a character for the "Euro" currency sign. |
| </p></li><li class="listitem" style="list-style-type: disc"><p> |
| The default script used for all Serbian language locales (sr_BA, sr_ME, sr_RS, |
| and the deprecated sr_CS and sr_SP) is cyrillic. With the "@latin" modifier |
| it gets switched to the latin script with the respective collation behaviour. |
| </p></li><li class="listitem" style="list-style-type: disc"><p> |
| The default charset of the "be_BY" locale (Belarusian/Belarus) is CP1251. |
| With the "@latin" modifier it's UTF-8. |
| </p></li><li class="listitem" style="list-style-type: disc"><p> |
| The default charset of the "tt_RU" locale (Tatar/Russia) is ISO-8859-5. |
| With the "@iqtelif" modifier it's UTF-8. |
| </p></li><li class="listitem" style="list-style-type: disc"><p> |
| The default charset of the "uz_UZ" locale (Uzbek/Uzbekistan) is ISO-8859-1. |
| With the "@cyrillic" modifier it's UTF-8. |
| </p></li><li class="listitem" style="list-style-type: disc"><p> |
| There's a class of characters in the Unicode character set, called the |
| "CJK Ambiguous Width" characters. For these characters, the width |
| returned by the wcwidth/wcswidth functions is usually 1. This can be a |
| problem with East-Asian languages, which historically use character sets |
| where these characters have a width of 2. Therefore, wcwidth/wcswidth |
| return 2 as the width of these characters when an East-Asian charset such |
| as GBK or SJIS is selected, or when UTF-8 is selected and the language is |
| specified as "zh" (Chinese), "ja" (Japanese), or "ko" (Korean). This is |
| not correct in all circumstances, hence the locale modifier "@cjknarrow" |
| can be used to force wcwidth/wcswidth to return 1 for the ambiguous width |
| characters. |
| </p></li><li class="listitem" style="list-style-type: disc"><p> |
| For the same class of "CJK Ambiguous Width" characters, it may be |
| desirable to handle them as double-width even when a non-CJK language |
| setting is selected. This supports e.g. certain graphic symbols used |
| by "Powerline" and provided by "Powerline fonts". Some terminals have |
| options to enforce this width handling (xterm -cjk_width, |
| mintty -o Charwidth=ambig-wide, putty configuration) but that alone |
| makes character rendering and locale information inconsistent for those |
| characters. The locale modifier "@cjkwide" supports consistent locale |
| response with this option; it forces wcwidth/wcswidth to return 2 for the |
| ambiguous width characters. |
| </p></li><li class="listitem" style="list-style-type: disc"><p> |
| As an alternative preference, CJK single-width may be enforced. |
| This feature is a |
| <a class="ulink" href="https://gitlab.freedesktop.org/terminal-wg/specifications/issues/9#note_406682" target="_top">proposal</a> |
| in the Terminals Working Group Specifications. |
| The mintty terminal implements it as an option with proper glyph scaling. |
| The locale modifier "@cjksingle" supports consistent locale response |
| with this option; it forces wcwidth/wcswidth to account at most 1 for |
| all characters. |
| </p></li></ul></div></div><div class="sect2"><div class="titlepage"><div><div><h3 class="title"><a name="setup-locale-how"></a>How to set the locale</h3></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: bullet; "><li class="listitem" style="list-style-type: disc"><p> |
| Assume that you've set one of the aforementioned environment variables to some |
| valid POSIX locale value, other than "C" and "POSIX". Assume further that |
| you're living in Japan. You might want to use the language code "ja" and the |
| territory "JP", thus setting, say, <code class="envar">LANG</code> to "ja_JP". You didn't |
| set a character set, so what will Cygwin use now? The default character set |
| is determined by the default Windows ANSI codepage for this language and |
| territory. Cygwin uses a character set which is the typical Unix-equivalent |
| to the Windows ANSI codepage. For instance:</p><pre class="screen"> |
| "en_US" ISO-8859-1 |
| "el_GR" ISO-8859-7 |
| "pl_PL" ISO-8859-2 |
| "pl_PL@euro" ISO-8859-15 |
| "ja_JP" EUCJP |
| "ko_KR" EUCKR |
| "te_IN" UTF-8 |
| </pre></li><li class="listitem" style="list-style-type: disc"><p> |
| You don't want to use the default character set? In that case you have to |
| specify the charset explicitly. For instance, assume you're from Japan and |
| don't want to use the japanese default charset EUC-JP, but the Windows |
| default charset SJIS. What you can do, for instance, is to set the |
| <code class="envar">LANG</code> variable in the <span class="command"><strong>mintty</strong></span> Cygwin Terminal |
| in the "Text" section of its "Options" dialog. If you're starting your |
| Cygwin session via a batch file or a shortcut to a batch file, you can also |
| just set LANG there:</p><pre class="screen"> |
| @echo off |
|
|
| C: |
| chdir C:\cygwin\bin |
| set LANG=ja_JP.SJIS |
| bash --login -i |
| </pre><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>For a list of locales supported by your Windows machine, use the new |
| <span class="command"><strong>locale -a</strong></span> command, which is part of the Cygwin package. |
| For a description see <a class="xref" href="locale.html" title="locale"><span class="refentrytitle">locale</span>(1)</a></p></div><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>For a list of supported character sets, see |
| <a class="xref" href="setup-locale.html#setup-locale-charsetlist" title="List of supported character sets">the section called “List of supported character sets”</a> |
| </p></div></li><li class="listitem" style="list-style-type: disc"><p> |
| Last, but not least, most singlebyte or doublebyte charsets have a big |
| disadvantage. Windows filesystems use the Unicode character set in the |
| UTF-16 encoding to store filename information. Not all characters |
| from the Unicode character set are available in a singlebyte or doublebyte |
| charset. While Cygwin has a workaround to access files with unusual |
| characters (see <a class="xref" href="using-specialnames.html#pathnames-unusual" title="Filenames with unusual (foreign) characters">the section called “Filenames with unusual (foreign) characters”</a>), a better |
| workaround is to use always the UTF-8 character set.</p><p><span class="emphasis"><em>UTF-8 is the only multibyte character set which can represent |
| every Unicode character.</em></span></p><pre class="screen"> |
| set LANG=es_MX.UTF-8 |
| </pre><p>For a description of the Unicode standard, see the homepage of the |
| <a class="ulink" href="http://www.unicode.org/" target="_top">Unicode Consortium</a>. |
| </p></li></ul></div></div><div class="sect2"><div class="titlepage"><div><div><h3 class="title"><a name="setup-locale-console"></a>The Windows Console character set</h3></div></div></div><p>Sometimes the Windows console is used to run Cygwin applications. |
| While terminal emulations like the Cygwin Terminal <span class="command"><strong>mintty</strong></span> |
| or <span class="command"><strong>xterm</strong></span> have a distinct way to set the character set |
| used for in- and output, the Windows console hasn't such a way, since it's |
| not an application in its own right.</p><p>This problem is solved in Cygwin as follows. When a Cygwin |
| process is started in a Windows console (either explicitly from cmd.exe, |
| or implicitly by, for instance, running the |
| <code class="filename">C:\cygwin\Cygwin.bat</code> batch file), the Console character |
| set is determined by the setting of the aforementioned |
| internationalization environment variables, the same way as described in |
| <a class="xref" href="setup-locale.html#setup-locale-how" title="How to set the locale">the section called “How to set the locale”</a>. </p><p>What is that good for? Why not switch the console character set with |
| the applications requirements? After all, the application knows if it uses |
| localization or not. However, what if a non-localized application calls |
| a remote application which itself is localized? This can happen with |
| <span class="command"><strong>ssh</strong></span> or <span class="command"><strong>rlogin</strong></span>. Both commands don't |
| have and don't need localization and they never call |
| <code class="function">setlocale</code>. Setting one of the internationalization |
| environment variable to the same charset as the remote machine before |
| starting <span class="command"><strong>ssh</strong></span> or <span class="command"><strong>rlogin</strong></span> fixes that |
| problem.</p></div><div class="sect2"><div class="titlepage"><div><div><h3 class="title"><a name="setup-locale-problems"></a>Potential Problems when using Locales</h3></div></div></div><p> |
| You can set the above internationalization variables not only when |
| starting the first Cygwin process, but also in your Cygwin shell on the |
| fly, even switch to yet another character set, and yet another. In bash |
| for instance:</p><pre class="screen"> |
| <code class="prompt">bash$</code> export LC_CTYPE="nl_BE.UTF-8" |
| </pre><p>However, here's a problem. At the start of the first Cygwin process |
| in a session, the Windows environment is converted from UTF-16 to UTF-8. |
| The environment is another of the system objects stored in UTF-16 in |
| Windows.</p><p>As long as the environment only contains ASCII characters, this is |
| no problem at all. But if it contains native characters, and you're planning |
| to use, say, GBK, the environment will result in invalid characters in |
| the GBK charset. This would be especially a problem in variables like |
| <code class="envar">PATH</code>. To circumvent the worst problems, Cygwin converts |
| the <code class="envar">PATH</code> environment variable to the charset set in the |
| environment, if it's different from the UTF-8 charset.</p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>Per POSIX, the name of an environment variable should only |
| consist of valid ASCII characters, and only of uppercase letters, digits, and |
| the underscore for maximum portability.</p></div><p>Very old symbolic links may pose a problem when switching charsets on |
| the fly. A symbolic link contains the filename of the target file the |
| symlink points to. When a symlink had been created with versions of Cygwin |
| prior to Cygwin 1.7, the current ANSI or OEM character set had been used to |
| store the target filename, dependent on the old <code class="envar">CYGWIN</code> |
| environment variable setting <code class="envar">codepage</code> (see <a class="xref" href="using-cygwinenv.html#cygwinenv-removed-options" title="Obsolete options">the section called “Obsolete options”</a>. If the target filename |
| contains non-ASCII characters and you use another character set than |
| your default ANSI/OEM charset, the target filename of the symlink is now |
| potentially an invalid character sequence in the new character set. |
| This behaviour is not different from the behaviour in other Operating |
| Systems. Recreate the symlink if that happens to you.</p></div><div class="sect2"><div class="titlepage"><div><div><h3 class="title"><a name="setup-locale-charsetlist"></a>List of supported character sets</h3></div></div></div><p>Last but not least, here's the list of currently supported character |
| sets. The left-hand expression is the name of the charset, as you would use |
| it in the internationalization environment variables as outlined above. |
| Note that charset specifiers are case-insensitive. <code class="literal">EUCJP</code> |
| is equivalent to <code class="literal">eucJP</code> or <code class="literal">eUcJp</code>. |
| Writing the charset in the exact case as given in the list below is a |
| good convention, though. |
| </p><p>The right-hand side is the number of the equivalent Windows |
| codepage as well as the Windows name of the codepage. They are only |
| noted here for reference. Don't try to use the bare codepage number or |
| the Windows name of the codepage as charset in locale specifiers, unless |
| they happen to be identical with the left-hand side. Especially in case |
| of the "CPxxx" style charsets, always use them with the trailing "CP".</p><p>This works:</p><pre class="screen"> |
| set LC_ALL=en_US.CP437 |
| </pre><p>This does <span class="emphasis"><em>not</em></span> work:</p><pre class="screen"> |
| set LC_ALL=en_US.437 |
| </pre><p>You can find a full list of Windows codepages on the Microsoft MSDN page |
| <a class="ulink" href="http://msdn.microsoft.com/en-us/library/dd317756(VS.85).aspx" target="_top">Code Page Identifiers</a>.</p><pre class="screen"> |
| Charset Codepage |
| ------------------- ------------------------------------------- |
| ASCII 20127 (US_ASCII) |
|
|
| CP437 437 (OEM United States) |
| CP720 720 (DOS Arabic) |
| CP737 737 (OEM Greek) |
| CP775 775 (OEM Baltic) |
| CP850 850 (OEM Latin 1, Western European) |
| CP852 852 (OEM Latin 2, Central European) |
| CP855 855 (OEM Cyrillic) |
| CP857 857 (OEM Turkish) |
| CP858 858 (OEM Latin 1 + Euro Symbol) |
| CP862 862 (OEM Hebrew) |
| CP866 866 (OEM Russian) |
| CP874 874 (ANSI/OEM Thai) |
| CP932 932 (Shift_JIS, not exactly identical to SJIS) |
| CP1125 1125 (OEM Ukraine) |
| CP1250 1250 (ANSI Central European) |
| CP1251 1251 (ANSI Cyrillic) |
| CP1252 1252 (ANSI Latin 1, Western European) |
| CP1253 1253 (ANSI Greek) |
| CP1254 1254 (ANSI Turkish) |
| CP1255 1255 (ANSI Hebrew) |
| CP1256 1256 (ANSI Arabic) |
| CP1257 1257 (ANSI Baltic) |
| CP1258 1258 (ANSI/OEM Vietnamese) |
|
|
| ISO-8859-1 28591 (ISO-8859-1) |
| ISO-8859-2 28592 (ISO-8859-2) |
| ISO-8859-3 28593 (ISO-8859-3) |
| ISO-8859-4 28594 (ISO-8859-4) |
| ISO-8859-5 28595 (ISO-8859-5) |
| ISO-8859-6 28596 (ISO-8859-6) |
| ISO-8859-7 28597 (ISO-8859-7) |
| ISO-8859-8 28598 (ISO-8859-8) |
| ISO-8859-9 28599 (ISO-8859-9) |
| ISO-8859-10 - (not available) |
| ISO-8859-11 - (not available) |
| ISO-8859-13 28603 (ISO-8859-13) |
| ISO-8859-14 - (not available) |
| ISO-8859-15 28605 (ISO-8859-15) |
| ISO-8859-16 - (not available) |
|
|
| Big5 950 (ANSI/OEM Traditional Chinese) |
| EUCCN or euc-CN 936 (ANSI/OEM Simplified Chinese) |
| EUCJP or euc-JP 20932 (EUC Japanese) |
| EUCKR or euc-KR 949 (EUC Korean) |
| GB2312 936 (ANSI/OEM Simplified Chinese) |
| GBK 936 (ANSI/OEM Simplified Chinese) |
| GEORGIAN-PS - (not available) |
| KOI8-R 20866 (KOI8-R Russian Cyrillic) |
| KOI8-U 21866 (KOI8-U Ukrainian Cyrillic) |
| PT154 - (not available) |
| SJIS - (not available, almost, but not exactly CP932) |
| TIS620 or TIS-620 874 (ANSI/OEM Thai) |
|
|
| UTF-8 or utf8 65001 (UTF-8) |
| </pre></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="setup-maxmem.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="setup-net.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="setup-files.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Changing Cygwin's Maximum Memory </td><td width="20%" align="center"><a accesskey="h" href="cygwin-ug-net.html">Home</a></td><td width="40%" align="right" valign="top"> Customizing bash</td></tr></table></div></body></html> |
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