linux/glibc/howto.html

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  14     <h1>How to write a GNU libc locale</h1>
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  22
  23     <p>This is a draft document explaining how to write locale files
  24       for GNU libc.  It will not go into details, but reference
  25       specifications.  It will on the other hand mention some of the
  26       pitfalls, and try to document the current practice.</p>
  27
  28     <h2>How to choose the locale file name</h2>
  29
  30       <p>Locale names consist of three parts.  The language code, the
  31         country/region code, and the optional modifier.  The format is
  32         language_REGION@modifier.  The language code is a code from
  33         ISO 639.  The two-letter code is prefered, but a three letter
  34         code is accepted if no two-letter code is available.  The
  35         country/region code is a code from ISO 3166.  If the language
  36         or region in question is missing in the ISO standard, one need
  37         to get the ISO standard updated before the locale will be
  38         included in glibc.</p>
  39
  40       <p>Little is known about the requirements for the naming of
  41         modifiers.  The following modifiers are currently used:
  42         abegede, cyrillic, euro and saaho.  This might indicate that
  43         lower case letters are prefered in modifier names.</p>
  44
  45       <p>It is recommended to follow RFC 3066 when selecting locale
  46         names.</p>
  47
  48       <ul>
  49
  50         <li><a href="http://www.unicode.org/onlinedat/countries.html">ISO
  51             3166</a></li>
  52
  53         <li><a href="http://www.loc.gov/standards/iso639-2/">ISO 639</a></li>
  54
  55         <li><a href="http://rfc.sunsite.dk/rfc/rfc3066.html"> RFC 3066
  56             - Tags for the Identification of Languages</a></li>
  57
  58       </ul>
  59
  60     <h2>Category order</h2>
  61
  62     <p>To make it easier to compare locales with each other, I
  63       recommend using the same order for the categories in all
  64       locales.  Any order will do, so I picked the order used in most
  65       locales, and decided to recommend this order:</p>
  66
  67     <ol>
  68       <li>LC_IDENTIFICATION
  69       <li>LC_CTYPE
  70       <li>LC_COLLATE
  71       <li>LC_MONETARY
  72       <li>LC_NUMERIC
  73       <li>LC_TIME
  74       <li>LC_MESSAGES
  75       <li>LC_PAPER
  76       <li>LC_NAME
  77       <li>LC_ADDRESS
  78       <li>LC_TELEPHONE
  79       <li>LC_MEASUREMENT
  80     </ol>
  81
  82     <h2>Reuse when possible</h2>
  83
  84     - "copy" from existing locales if the content should be identical
  85
  86     <h2>LD_IDENTIFICATION</h2>
  87
  88     - standard refs in the LD_IDENTIFICATION
  89
  90     - quotes around the text
  91
  92     - no &lt;U#&gt;, use normal ASCII
  93
  94     <h2>LC_MESSAGES</h2>
  95
  96     - yes/no expr should have the form ^[yYnN<extra>], without 0 and 1
  97       and without trailing ".*".
  98
  99     <h2>Standard documents and specifications</h2>
 100
 101     <h2>Testing the new locale file</h2>
 102
 103         <p>To test a new locale on a test machine, do the
 104         following:</p>
 105
 106         <ul>
 107
 108           <li>Copy the new locale to
 109             <tt>/usr/share/i18n/locales/<em>filename</em></tt></li>
 110
 111           <li>Run <tt>localedef -i <em>inputfile</em> -c -f
 112               <em>charset<em> <em>locale</em></tt> to generate a
 113             binary locale file in
 114             <tt>/usr/lib/locale/<em>locale</em>/</tt></li>
 115
 116           <li>Test it using LANG=<em>locale</em>, for example by
 117             running <tt>date</tt></li>
 118
 119         </ul>
 120
 121         <p>Example, generating a new <tt>de_DE@euro</tt> locale using
 122           the ISO-8859-15 charset and save it as 'de_DE':</p>
 123
 124         <pre>
 125           cp de_DE@euro /usr/share/i18n/locales/de_DE@euro
 126           localedef -i de_DE@euro -c -f ISO-8859-15 de_DE
 127           LANG=de_DE date
 128         </pre>
 129
 130     </div>
 131
 132     <hr>
 133     <address><a href="mailto:pere@hungry.com">Petter Reinholdtsen</a></address>
 134 <!-- Created: Sun Mar 21 18:14:42 CET 2004 -->
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 136 Last modified: Mon Aug  9 01:09:09 CEST 2004
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