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#208082: don't use LC_ALL, prefer system-wide LANG, don't set LC_CTYPE when LANG
is already set, advertise utf-8 a bit more...

1 neysx 1.1 <?xml version='1.0' encoding="UTF-8"?>
2 jkt 1.49 <!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/utf-8.xml,v 1.48 2008/05/19 21:08:38 swift Exp $ -->
3 neysx 1.1 <!DOCTYPE guide SYSTEM "/dtd/guide.dtd">
4    
5     <guide link="/doc/en/utf-8.xml">
6     <title>Using UTF-8 with Gentoo</title>
7    
8     <author title="Author">
9     <mail link="slarti@gentoo.org">Thomas Martin</mail>
10     </author>
11     <author title="Contributor">
12     <mail link="devil@gentoo.org.ua">Alexander Simonov</mail>
13     </author>
14 fox2mike 1.20 <author title="Editor">
15 neysx 1.21 <mail link="fox2mike@gentoo.org">Shyam Mani</mail>
16 fox2mike 1.20 </author>
17 neysx 1.1
18     <abstract>
19     This guide shows you how to set up and use the UTF-8 Unicode character set with
20     your Gentoo Linux system, after explaining the benefits of Unicode and more
21     specifically UTF-8.
22     </abstract>
23    
24 fox2mike 1.20 <!-- The content of this document is licensed under the CC-BY-SA license -->
25     <!-- See http://creativecommons.org/licenses/by-sa/2.5 -->
26 neysx 1.1 <license />
27    
28 jkt 1.49 <version>2.26</version>
29     <date>2008-10-10</date>
30 neysx 1.1
31     <chapter>
32     <title>Character Encodings</title>
33     <section>
34     <title>What is a Character Encoding?</title>
35     <body>
36    
37     <p>
38     Computers do not understand text themselves. Instead, every character is
39     represented by a number. Traditionally, each set of numbers used to represent
40     alphabets and characters (known as a coding system, encoding or character set)
41     was limited in size due to limitations in computer hardware.
42     </p>
43    
44     </body>
45     </section>
46     <section>
47     <title>The History of Character Encodings</title>
48     <body>
49    
50     <p>
51     The most common (or at least the most widely accepted) character set is
52     <b>ASCII</b> (American Standard Code for Information Interchange). It is widely
53     held that ASCII is the most successful software standard ever. Modern ASCII
54     was standardised in 1986 (ANSI X3.4, RFC 20, ISO/IEC 646:1991, ECMA-6) by the
55     American National Standards Institute.
56     </p>
57    
58     <p>
59     ASCII is strictly seven-bit, meaning that it uses bit patterns representable
60     with seven binary digits, which provides a range of 0 to 127 in decimal. These
61     include 32 non-visible control characters, most between 0 and 31, with the
62     final control character, DEL or delete at 127. Characters 32 to 126 are
63     visible characters: a space, punctuation marks, Latin letters and numbers.
64     </p>
65    
66     <p>
67     The eighth bit in ASCII was originally used as a parity bit for error checking.
68     If this is not desired, it is left as 0. This means that, with ASCII, each
69     character is represented by a single byte.
70     </p>
71    
72     <p>
73     Although ASCII was enough for communication in modern English, in other
74     European languages that include accented characters, things were not so easy.
75     The ISO 8859 standards were developed to meet these needs. They were backwards
76     compatible with ASCII, but instead of leaving the eighth bit blank, they used
77     it to allow another 127 characters in each encoding. ISO 8859's limitations
78     soon came to light, and there are currently 15 variants of the ISO 8859
79     standard (8859-1 through to 8859-15). Outside of the ASCII-compatible byte
80     range of these character sets, there is often conflict between the letters
81     represented by each byte. To complicate interoperability between character
82     encodings further, Windows-1252 is used in some versions of Microsoft Windows
83     instead for Western European languages. This is a superset of ISO 8859-1,
84     however it is different in several ways. These sets do all retain ASCII
85     compatibility, however.
86     </p>
87    
88     <p>
89     The necessary development of completely different single-byte encodings for
90     non-Latin alphabets, such as EUC (Extended Unix Coding) which is used for
91     Japanese and Korean (and to a lesser extent Chinese) created more confusion,
92     while other operating systems still used different character sets for the same
93     languages, for example, Shift-JIS and ISO-2022-JP. Users wishing to view
94     cyrillic glyphs had to choose between KOI8-R for Russian and Bulgarian or
95     KOI8-U for Ukrainian, as well as all the other cyrillic encodings such as the
96     unsuccessful ISO 8859-5, and the common Windows-1251 set. All of these
97     character sets broke most compatibility with ASCII (although KOI8 encodings
98     place cyrillic characters in Latin order, so in case the eighth bit is
99     stripped, text is still decipherable on an ASCII terminal through case-reversed
100     transliteration.)
101     </p>
102    
103     <p>
104     This has led to confusion, and also to an almost total inability for
105     multilingual communication, especially across different alphabets. Enter
106     Unicode.
107     </p>
108    
109     </body>
110     </section>
111     <section>
112     <title>What is Unicode?</title>
113     <body>
114    
115     <p>
116 bennyc 1.11 Unicode throws away the traditional single-byte limit of character sets. It
117     uses 17 "planes" of 65,536 code points to describe a maximum of 1,114,112
118     characters. As the first plane, aka. "Basic Multilingual Plane" or BMP,
119     contains almost everything you will ever use, many have made the wrong
120     assumption that Unicode was a 16-bit character set.
121 neysx 1.1 </p>
122    
123     <p>
124     Unicode has been mapped in many different ways, but the two most common are
125     <b>UTF</b> (Unicode Transformation Format) and <b>UCS</b> (Universal Character
126     Set). A number after UTF indicates the number of bits in one unit, while the
127     number after UCS indicates the number of bytes. UTF-8 has become the most
128     widespread means for the interchange of Unicode text as a result of its
129     eight-bit clean nature, and it is the subject of this document.
130     </p>
131    
132     </body>
133     </section>
134     <section>
135     <title>UTF-8</title>
136     <body>
137    
138     <p>
139     UTF-8 is a variable-length character encoding, which in this instance means
140     that it uses 1 to 4 bytes per symbol. So, the first UTF-8 byte is used for
141     encoding ASCII, giving the character set full backwards compatibility with
142     ASCII. UTF-8 means that ASCII and Latin characters are interchangeable with
143     little increase in the size of the data, because only the first bit is used.
144     Users of Eastern alphabets such as Japanese, who have been assigned a higher
145     byte range are unhappy, as this results in as much as a 50% redundancy in their
146     data.
147     </p>
148    
149     </body>
150     </section>
151     <section>
152     <title>What UTF-8 Can Do for You</title>
153     <body>
154    
155     <p>
156     UTF-8 allows you to work in a standards-compliant and internationally accepted
157 bennyc 1.11 multilingual environment, with a comparatively low data redundancy. UTF-8 is
158 neysx 1.1 the preferred way for transmitting non-ASCII characters over the Internet,
159     through Email, IRC or almost any other medium. Despite this, many people regard
160     UTF-8 in online communication as abusive. It is always best to be aware of the
161     attitude towards UTF-8 in a specific channel, mailing list or Usenet group
162     before using <e>non-ASCII</e> UTF-8.
163     </p>
164    
165     </body>
166     </section>
167     </chapter>
168    
169     <chapter>
170     <title>Setting up UTF-8 with Gentoo Linux</title>
171     <section>
172     <title>Finding or Creating UTF-8 Locales</title>
173     <body>
174    
175     <p>
176     Now that you understand the principles behind Unicode, you're ready to start
177     using UTF-8 with your system.
178     </p>
179    
180     <p>
181     The preliminary requirement for UTF-8 is to have a version of glibc installed
182     that has national language support. The recommend means to do this is the
183 rane 1.43 <path>/etc/locale.gen</path> file. It is beyond the scope of this document to
184     explain the usage of this file though. It is explained in the <uri
185     link="/doc/en/guide-localization.xml#doc_chap3_sect3">Gentoo Localization
186 neysx 1.1 Guide</uri>.
187     </p>
188    
189     <p>
190     Next, we'll need to decide whether a UTF-8 locale is already available for our
191     language, or whether we need to create one.
192     </p>
193    
194     <pre caption="Checking for an existing UTF-8 locale">
195     <comment>(Replace "en_GB" with your desired locale setting)</comment>
196     # <i>locale -a | grep 'en_GB'</i>
197     en_GB
198 bennyc 1.12 en_GB.UTF-8
199 neysx 1.1 </pre>
200    
201     <p>
202     From the output of this command line, we need to take the result with a suffix
203 bennyc 1.12 similar to <c>.UTF-8</c>. If there is no result with a suffix similar to
204     <c>.UTF-8</c>, we need to create a UTF-8 compatible locale.
205 neysx 1.1 </p>
206    
207     <note>
208     Only execute the following code listing if you do not have a UTF-8 locale
209     available for your language.
210     </note>
211    
212     <pre caption="Creating a UTF-8 locale">
213     <comment>(Replace "en_GB" with your desired locale setting)</comment>
214 bennyc 1.12 # <i>localedef -i en_GB -f UTF-8 en_GB.UTF-8</i>
215 neysx 1.1 </pre>
216    
217 bennyc 1.11 <p>
218     Another way to include a UTF-8 locale is to add it to the
219 rane 1.43 <path>/etc/locale.gen</path> file and generate necessary locales with
220     <c>locale-gen</c> command.
221 bennyc 1.11 </p>
222    
223 rane 1.43 <pre caption="Line in /etc/locale.gen">
224     en_GB.UTF-8 UTF-8
225 bennyc 1.11 </pre>
226    
227 neysx 1.1 </body>
228     </section>
229     <section>
230     <title>Setting the Locale</title>
231     <body>
232    
233     <p>
234 nightmorph 1.45 There is one environment variable that needs to be set in order to use our new
235 jkt 1.49 UTF-8 locales: <c>LC_CTYPE</c> (or optionally <c>LANG</c>, if you want to change
236     the system language as well). There are also many different ways to set it; some
237     people prefer to only have a UTF-8 environment for a specific user, in which
238     case they set them in their <path>~/.profile</path> (if you use <c>/bin/sh</c>),
239     <path>~/.bash_profile</path> or <path>~/.bashrc</path> (if you use
240     <c>/bin/bash</c>). More details and best practices can be found in our <uri
241     link="/doc/en/guide-localization.xml">Locallization Guide</uri>.
242 swift 1.18 </p>
243    
244     <p>
245 swift 1.48 Others prefer to set the locale globally. One specific circumstance where
246     the author particularly recommends doing this is when
247 swift 1.17 <path>/etc/init.d/xdm</path> is in use, because
248 bennyc 1.12 this init script starts the display manager and desktop before any of the
249     aforementioned shell startup files are sourced, and so before any of the
250     variables are in the environment.
251 neysx 1.1 </p>
252    
253 bennyc 1.12 <p>
254     Setting the locale globally should be done using
255 swift 1.15 <path>/etc/env.d/02locale</path>. The file should look something like the
256 bennyc 1.12 following:
257     </p>
258    
259     <pre caption="Demonstration /etc/env.d/02locale">
260     <comment>(As always, change "en_GB.UTF-8" to your locale)</comment>
261 nightmorph 1.45 LANG="en_GB.UTF-8"
262 bennyc 1.12 </pre>
263    
264 nightmorph 1.45 <note>
265     You can also substitute <c>LC_ALL</c> for <c>LANG</c>. This sets your locale
266     for all categories, including numerical and currency values. On a very few
267     systems, it might cause some issues. However, most users should be able to use
268     <c>LC_ALL</c> without problems. For more information on the categories affected
269     by using <c>LC_ALL</c>, please read the <uri
270     link="http://www.gnu.org/software/libc/manual/html_node/Locale-Categories.html#Locale-Categories">GNU
271     locale page</uri>.
272     </note>
273    
274 bennyc 1.12 <p>
275     Next, the environment must be updated with the change.
276     </p>
277 bennyc 1.10
278 bennyc 1.12 <pre caption="Updating the environment">
279     # <i>env-update</i>
280     >>> Regenerating /etc/ld.so.cache...
281     * Caching service dependencies ...
282 swift 1.13 # <i>source /etc/profile</i>
283 bennyc 1.10 </pre>
284    
285 bennyc 1.12 <p>
286     Now, run <c>locale</c> with no arguments to see if we have the correct
287     variables in our environment:
288     </p>
289    
290     <pre caption="Checking if our new locale is in the environment">
291     # <i>locale</i>
292 swift 1.16 LANG=
293 bennyc 1.12 LC_CTYPE="en_GB.UTF-8"
294     LC_NUMERIC="en_GB.UTF-8"
295     LC_TIME="en_GB.UTF-8"
296     LC_COLLATE="en_GB.UTF-8"
297     LC_MONETARY="en_GB.UTF-8"
298     LC_MESSAGES="en_GB.UTF-8"
299     LC_PAPER="en_GB.UTF-8"
300     LC_NAME="en_GB.UTF-8"
301     LC_ADDRESS="en_GB.UTF-8"
302     LC_TELEPHONE="en_GB.UTF-8"
303     LC_MEASUREMENT="en_GB.UTF-8"
304     LC_IDENTIFICATION="en_GB.UTF-8"
305     LC_ALL=en_GB.UTF-8
306 neysx 1.1 </pre>
307    
308 bennyc 1.10 <p>
309 bennyc 1.12 That's everything. You are now using UTF-8 locales, and the next hurdle is the
310     configuration of the applications you use from day to day.
311 neysx 1.1 </p>
312    
313     </body>
314     </section>
315     </chapter>
316    
317     <chapter>
318     <title>Application Support</title>
319     <section>
320     <body>
321    
322     <p>
323     When Unicode first started gaining momentum in the software world, multibyte
324     character sets were not well suited to languages like C, in which many of the
325     day-to-day programs people use are written. Even today, some programs are not
326     able to handle UTF-8 properly. Fortunately, most are!
327     </p>
328    
329     </body>
330     </section>
331     <section>
332     <title>Filenames, NTFS, and FAT</title>
333     <body>
334    
335     <p>
336     There are several NLS options in the Linux kernel configuration menu, but it is
337     important to not become confused! For the most part, the only thing you need to
338     do is to build UTF-8 NLS support into your kernel, and change the default NLS
339     option to utf8.
340     </p>
341    
342     <pre caption="Kernel configuration steps for UTF-8 NLS">
343     File Systems --&gt;
344     Native Language Support --&gt;
345     (utf8) Default NLS Option
346     &lt;*&gt; NLS UTF8
347     <comment>(Also &lt;*&gt; other character sets that are in use in
348     your FAT filesystems or Joilet CD-ROMs.)</comment>
349     </pre>
350    
351     <p>
352     If you plan on mounting NTFS partitions, you may need to specify an <c>nls=</c>
353 nightmorph 1.40 option with mount. If you plan on mounting FAT partitions, you may need to
354 fox2mike 1.28 specify a <c>codepage=</c> option with mount. Optionally, you can also set a
355     default codepage for FAT in the kernel configuration. Note that the
356     <c>codepage</c> option with mount will override the kernel settings.
357     </p>
358    
359     <pre caption="FAT settings in kernel configuration">
360     File Systems --&gt;
361     DOS/FAT/NT Filesystems --&gt;
362     (437) Default codepage for fat
363     </pre>
364    
365     <p>
366     You should avoid setting <c>Default iocharset for fat</c> to UTF-8, as it is
367     not recommended. Instead, you may want to pass the option utf8=true when
368     mounting your FAT partitions. For further information, see <c>man mount</c> and
369     the kernel documentation at
370     <path>/usr/src/linux/Documentation/filesystems/vfat.txt</path>.
371 neysx 1.1 </p>
372    
373     <p>
374     For changing the encoding of filenames, <c>app-text/convmv</c> can be used.
375     </p>
376    
377     <pre caption="Example usage of convmv">
378     # <i>emerge --ask app-text/convmv</i>
379 fox2mike 1.29 <comment>(Command format)</comment>
380     # <i>convmv -f &lt;current-encoding&gt; -t utf-8 &lt;filename&gt;</i>
381     <comment>(Substitute iso-8859-1 with the charset you are converting
382     from)</comment>
383     # <i>convmv -f iso-8859-1 -t utf-8 filename</i>
384 neysx 1.1 </pre>
385    
386     <p>
387     For changing the <e>contents</e> of files, use the <c>iconv</c> utility,
388     bundled with <c>glibc</c>:
389     </p>
390    
391     <pre caption="Example usage of iconv">
392     <comment>(substitute iso-8859-1 with the charset you are converting from)</comment>
393     <comment>(Check the output is sane)</comment>
394 swift 1.48 # <i>iconv -f iso-8859-1 -t utf-8 filename</i>
395 neysx 1.1 <comment>(Convert a file, you must create another file)</comment>
396     # <i>iconv -f iso-8859-1 -t utf-8 filename > newfile</i>
397     </pre>
398    
399     <p>
400     <c>app-text/recode</c> can also be used for this purpose.
401     </p>
402    
403     </body>
404     </section>
405     <section>
406     <title>The System Console</title>
407     <body>
408    
409     <impo>
410     You need >=sys-apps/baselayout-1.11.9 for Unicode on the console.
411     </impo>
412    
413     <p>
414     To enable UTF-8 on the console, you should edit <path>/etc/rc.conf</path> and
415     set <c>UNICODE="yes"</c>, and also read the comments in that file -- it is
416     important to have a font that has a good range of characters if you plan on
417 nightmorph 1.46 making the most of Unicode. For this to work, make sure you have properly
418     created a Unicode locale as explained in <uri link="#doc_chap1">Chapter
419     1</uri>.
420 neysx 1.1 </p>
421    
422     <p>
423     The <c>KEYMAP</c> variable, set in <path>/etc/conf.d/keymaps</path>, should
424 swift 1.48 have a Unicode keymap specified.
425 neysx 1.1 </p>
426    
427     <pre caption="Example /etc/conf.d/keymaps snippet">
428     <comment>(Change "uk" to your local layout)</comment>
429 fox2mike 1.26 KEYMAP="uk"
430 neysx 1.1 </pre>
431    
432     </body>
433     </section>
434     <section>
435     <title>Ncurses and Slang</title>
436     <body>
437    
438     <note>
439     Ignore any mention of Slang in this section if you do not have it installed or
440     do not use it.
441     </note>
442    
443     <p>
444     It is wise to add <c>unicode</c> to your global USE flags in
445     <path>/etc/make.conf</path>, and then to remerge <c>sys-libs/ncurses</c> and
446 swift 1.30 <c>sys-libs/slang</c> if appropriate. Portage will do this automatically when
447     you update your system:
448 neysx 1.1 </p>
449    
450 swift 1.30 <pre caption="Updating your system">
451     # <i>emerge --update --deep --newuse world</i>
452 neysx 1.1 </pre>
453    
454     <p>
455     We also need to rebuild packages that link to these, now the USE changes have
456 bennyc 1.11 been applied. The tool we use (<c>revdep-rebuild</c>) is part of the
457     <c>gentoolkit</c> package.
458 neysx 1.1 </p>
459    
460     <pre caption="Rebuilding of programs that link to ncurses or slang">
461     # <i>revdep-rebuild --soname libncurses.so.5</i>
462     # <i>revdep-rebuild --soname libslang.so.1</i>
463     </pre>
464    
465     </body>
466     </section>
467     <section>
468     <title>KDE, GNOME and Xfce</title>
469     <body>
470    
471     <p>
472     All of the major desktop environments have full Unicode support, and will
473     require no further setup than what has already been covered in this guide. This
474     is because the underlying graphical toolkits (Qt or GTK+2) are UTF-8 aware.
475     Subsequently, all applications running on top of these toolkits should be
476     UTF-8-aware out of the box.
477     </p>
478    
479     <p>
480     The exceptions to this rule come in Xlib and GTK+1. GTK+1 requires a
481     iso-10646-1 FontSpec in the ~/.gtkrc, for example
482     <c>-misc-fixed-*-*-*-*-*-*-*-*-*-*-iso10646-1</c>. Also, applications using
483     Xlib or Xaw will need to be given a similar FontSpec, otherwise they will not
484     work.
485     </p>
486    
487     <note>
488     If you have a version of the gnome1 control center around, use that instead.
489     Pick any iso10646-1 font from there.
490     </note>
491    
492     <pre caption="Example ~/.gtkrc (for GTK+1) that defines a Unicode compatible font">
493     style "user-font"
494     {
495     fontset="-misc-fixed-*-*-*-*-*-*-*-*-*-*-iso10646-1"
496     }
497     widget_class "*" style "user-font"
498     </pre>
499    
500     <p>
501     If an application has support for both a Qt and GTK+2 GUI, the GTK+2 GUI will
502     generally give better results with Unicode.
503     </p>
504    
505     </body>
506     </section>
507     <section>
508     <title>X11 and Fonts</title>
509     <body>
510    
511 bennyc 1.11 <impo>
512     <c>x11-base/xorg-x11</c> has far better support for Unicode than XFree86
513     and is <e>highly</e> recommended.
514     </impo>
515    
516 neysx 1.1 <p>
517     TrueType fonts have support for Unicode, and most of the fonts that ship with
518     Xorg have impressive character support, although, obviously, not every single
519     glyph available in Unicode has been created for that font. To build fonts
520     (including the Bitstream Vera set) with support for East Asian letters with X,
521     make sure you have the <c>cjk</c> USE flag set. Many other applications utilise
522     this flag, so it may be worthwhile to add it as a permanent USE flag.
523     </p>
524    
525     <p>
526     Also, several font packages in Portage are Unicode aware.
527     </p>
528    
529     <pre caption="Optional: Install some more Unicode-aware fonts">
530     # <i>emerge terminus-font intlfonts freefonts cronyx-fonts corefonts</i>
531     </pre>
532    
533     </body>
534     </section>
535     <section>
536     <title>Window Managers and Terminal Emulators</title>
537     <body>
538    
539     <p>
540 bennyc 1.11 Window managers not built on GTK or Qt generally have very good Unicode
541     support, as they often use the Xft library for handling fonts. If your window
542     manager does not use Xft for fonts, you can still use the FontSpec mentioned in
543     the previous section as a Unicode font.
544 neysx 1.1 </p>
545    
546     <p>
547     Terminal emulators that use Xft and support Unicode are harder to come by.
548     Aside from Konsole and gnome-terminal, the best options in Portage are
549     <c>x11-terms/rxvt-unicode</c>, <c>xfce-extra/terminal</c>,
550 neysx 1.34 <c>gnustep-apps/terminal</c>, <c>x11-terms/mlterm</c>, or plain
551     <c>x11-terms/xterm</c> when built with the <c>unicode</c> USE flag and invoked
552     as <c>uxterm</c>. <c>app-misc/screen</c> supports UTF-8 too, when invoked as
553 rane 1.35 <c>screen -U</c> or the following is put into the <path>~/.screenrc</path>:
554 neysx 1.1 </p>
555    
556     <pre caption="~/.screenrc for UTF-8">
557     defutf8 on
558     </pre>
559    
560     </body>
561     </section>
562     <section>
563     <title>Vim, Emacs, Xemacs and Nano</title>
564     <body>
565    
566     <p>
567 swift 1.48 Vim provides full UTF-8 support, and also has builtin detection of UTF-8 files.
568 swift 1.27 For further information in Vim, use <c>:help mbyte.txt</c>.
569 neysx 1.1 </p>
570    
571     <p>
572 swift 1.27 Emacs 22.x and higher has full UTF-8 support as well. Xemacs 22.x does not
573 swift 1.48 support combining characters yet.
574 swift 1.27 </p>
575    
576     <p>
577 swift 1.48 Lower versions of Emacs and/or Xemacs might require you to install
578 swift 1.27 <c>app-emacs/mule-ucs</c> and/or <c>app-xemacs/mule-ucs</c>
579     and add the following code to your <path>~/.emacs</path> to have support for CJK
580     languages in UTF-8:
581     </p>
582    
583     <pre caption="Emacs CJK UTF-8 support">
584     (require 'un-define)
585     (require 'jisx0213)
586     (set-language-environment "Japanese")
587     (set-default-coding-systems 'utf-8)
588     (set-terminal-coding-system 'utf-8)
589     </pre>
590    
591     <p>
592 nightmorph 1.38 Nano has provided full UTF-8 support since version 1.3.6.
593 neysx 1.1 </p>
594    
595     </body>
596     </section>
597     <section>
598     <title>Shells</title>
599     <body>
600    
601     <p>
602     Currently, <c>bash</c> provides full Unicode support through the GNU readline
603 nightmorph 1.47 library. Z Shell (<c>zsh</c>) offers Unicode support with the <c>unicode</c> USE
604     flag.
605 neysx 1.1 </p>
606    
607     <p>
608     The C shell, <c>tcsh</c> and <c>ksh</c> do not provide UTF-8 support at all.
609     </p>
610    
611     </body>
612     </section>
613     <section>
614     <title>Irssi</title>
615     <body>
616    
617     <p>
618 swift 1.33 Irssi has complete UTF-8 support, although it does require a user
619 cam 1.5 to set an option.
620 neysx 1.1 </p>
621    
622     <pre caption="Enabling UTF-8 in Irssi">
623 nightmorph 1.39 /set term_charset UTF-8
624 neysx 1.1 </pre>
625    
626     <p>
627     For channels where non-ASCII characters are often exchanged in non-UTF-8
628     charsets, the <c>/recode</c> command may be used to convert the characters.
629     Type <c>/help recode</c> for more information.
630     </p>
631    
632     </body>
633     </section>
634     <section>
635     <title>Mutt</title>
636     <body>
637    
638     <p>
639     The Mutt mail user agent has very good Unicode support. To use UTF-8 with Mutt,
640 rane 1.36 you don't need to put anything in your configuration files. Mutt will work
641     under unicode enviroment without modification if all your configuration files
642     (signature included) are UTF-8 encoded.
643 neysx 1.1 </p>
644    
645     <note>
646     You may still see '?' in mail you read with Mutt. This is a result of people
647 bennyc 1.11 using a mail client which does not indicate the used charset. You can't do much
648     about this than to ask them to configure their client correctly.
649 neysx 1.1 </note>
650    
651     <p>
652     Further information is available from the <uri
653 neysx 1.25 link="http://wiki.mutt.org/index.cgi?MuttFaq/Charset">Mutt Wiki</uri>.
654 neysx 1.1 </p>
655    
656     </body>
657     </section>
658     <section>
659 swift 1.14 <title>Man</title>
660     <body>
661    
662     <p>
663 swift 1.48 Man pages are an integral part of any Linux machine. To ensure that any
664     unicode in your man pages render correctly, edit <path>/etc/man.conf</path>
665 swift 1.14 and replace a line as shown below.
666     </p>
667    
668     <pre caption="man.conf changes for Unicode support">
669     <comment>(This is the old line)</comment>
670     NROFF /usr/bin/nroff -Tascii -c -mandoc
671     <comment>(Replace the one above with this)</comment>
672     NROFF /usr/bin/nroff -mandoc -c
673     </pre>
674    
675     </body>
676     </section>
677     <section>
678 fox2mike 1.20 <title>elinks and links</title>
679     <body>
680    
681     <p>
682     These are commonly used text-based browsers, and we shall see how we can enable
683     UTF-8 support on them. On <c>elinks</c> and <c>links</c>, there are two ways to
684     go about this, one using the Setup option from within the browser or editing the
685     config file. To set the option through the browser, open a site with
686     <c>elinks</c> or <c>links</c> and then <c>Alt+S</c> to enter the Setup Menu then
687     select Terminal options, or press <c>T</c>. Scroll down and select the last
688     option <c>UTF-8 I/O</c> by pressing Enter. Then Save and exit the menu. On
689     <c>links</c> you may have to do a repeat <c>Alt+S</c> and then press <c>S</c> to
690     save. The config file option, is shown below.
691     </p>
692    
693     <pre caption="Enabling UTF-8 for elinks/links">
694     <comment>(For elinks, edit /etc/elinks/elinks.conf or ~/.elinks/elinks.conf and
695     add the following line)</comment>
696     set terminal.linux.utf_8_io = 1
697    
698     <comment>(For links, edit ~/.links/links.cfg and add the following
699     line)</comment>
700     terminal "xterm" 0 1 0 us-ascii utf-8
701     </pre>
702    
703     </body>
704     </section>
705     <section>
706 fox2mike 1.41 <title>Samba</title>
707     <body>
708    
709     <p>
710     Samba is a software suite which implements the SMB (Server Message Block)
711     protocol for UNIX systems such as Macs, Linux and FreeBSD. The protocol
712     is also sometimes referred to as the Common Internet File System (CIFS). Samba
713 rane 1.42 also includes the NetBIOS system - used for file sharing over windows networks.
714 fox2mike 1.41 </p>
715    
716     <pre caption="Enabling UTF-8 for Samba">
717     <comment>(Edit /etc/samba/smb.conf and add the following under the [global] section)</comment>
718     dos charset = 1255
719     unix charset = UTF-8
720     display charset = UTF-8
721     </pre>
722    
723     </body>
724     </section>
725     <section>
726 neysx 1.1 <title>Testing it all out</title>
727     <body>
728    
729     <p>
730     There are numerous UTF-8 test websites around. <c>net-www/w3m</c>,
731     <c>net-www/links</c>, <c>net-www/elinks</c>, <c>net-www/lynx</c> and all
732 cam 1.3 Mozilla based browsers (including Firefox) support UTF-8. Konqueror and Opera
733     have full UTF-8 support too.
734 neysx 1.1 </p>
735    
736     <p>
737     When using one of the text-only web browsers, make absolutely sure you are
738     using a Unicode-aware terminal.
739     </p>
740    
741     <p>
742     If you see certain characters displayed as boxes with letters or numbers
743     inside, this means that your font does not have a character for the symbol or
744     glyph that the UTF-8 wants. Instead, it displays a box with the hex code of the
745     UTF-8 symbol.
746     </p>
747    
748     <ul>
749     <li>
750     <uri link="http://www.w3.org/2001/06/utf-8-test/UTF-8-demo.html">A W3C
751     UTF-8 Test Page</uri>
752     </li>
753     <li>
754     <uri link="http://titus.uni-frankfurt.de/indexe.htm?/unicode/unitest.htm">
755     A UTF-8 test page provided by the University of Frankfurt</uri>
756     </li>
757     </ul>
758    
759     </body>
760     </section>
761     <section>
762     <title>Input Methods</title>
763     <body>
764    
765     <p>
766     <e>Dead keys</e> may be used to input characters in X that are not included on
767     your keyboard. These work by pressing your right Alt key (or in some countries,
768     AltGr) and an optional key from the non-alphabetical section of the keyboard to
769     the left of the return key at once, releasing them, and then pressing a letter.
770     The dead key should modify it. Input can be further modified by using the Shift
771     key at the same time as pressing the AltGr and modifier.
772     </p>
773    
774     <p>
775     To enable dead keys in X, you need a layout that supports it. Most European
776     layouts already have dead keys with the default variant. However, this is not
777     true of North American layouts. Although there is a degree of inconsistency
778     between layouts, the easiest solution seems to be to use a layout in the form
779     "en_US" rather than "us", for example. The layout is set in
780     <path>/etc/X11/xorg.conf</path> like so:
781     </p>
782    
783     <pre caption="/etc/X11/xorg.conf snippet">
784     Section "InputDevice"
785     Identifier "Keyboard0"
786     Driver "kbd"
787     Option "XkbLayout" "en_US" <comment># Rather than just "us"</comment>
788     <comment>(Other Xkb options here)</comment>
789     EndSection
790     </pre>
791    
792     <note>
793     The preceding change only needs to be applied if you are using a North American
794     layout, or another layout where dead keys do not seem to be working. European
795     users should have working dead keys as is.
796     </note>
797    
798     <p>
799 bennyc 1.11 This change will come into effect when your X server is restarted. To apply the
800 neysx 1.1 change now, use the <c>setxkbmap</c> tool, for example, <c>setxkbmap en_US</c>.
801     </p>
802    
803     <p>
804     It is probably easiest to describe dead keys with examples. Although the
805 bennyc 1.11 results are locale dependent, the concepts should remain the same regardless of
806 neysx 1.1 locale. The examples contain UTF-8, so to view them you need to either tell
807     your browser to view the page as UTF-8, or have a UTF-8 locale already
808     configured.
809     </p>
810    
811     <p>
812     When I press AltGr and [ at once, release them, and then press a, 'ä' is
813 bennyc 1.11 produced. When I press AltGr and [ at once, and then press e, 'ë' is produced.
814     When I press AltGr and ; at once, 'á' is produced, and when I press AltGr and ;
815     at once, release them, and then press e, 'é' is produced.
816 neysx 1.1 </p>
817    
818     <p>
819     By pressing AltGr, Shift and [ at once, releasing them, and then pressing a, a
820     Scandinavian 'å' is produced. Similarly, when I press AltGr, Shift and [ at
821     once, release <e>only</e> the [, and then press it again, '˚' is produced.
822     Although it looks like one, this (U+02DA) is not the same as a degree symbol
823     (U+00B0). This works for other accents produced by dead keys — AltGr and [,
824     releasing only the [, then pressing it again makes '¨'.
825     </p>
826    
827     <p>
828     AltGr can be used with alphabetical keys alone. For example, AltGr and m, a
829 bennyc 1.12 Greek lower-case letter mu is produced: 'µ'. AltGr and s produce a
830     scharfes s or esszet: 'ß'. As many European users would expect (because
831 swift 1.31 it is marked on their keyboard), AltGr and 4 (or E depending on the keyboard
832     layout) produces a Euro sign, '€'.
833 neysx 1.1 </p>
834    
835     </body>
836     </section>
837     <section>
838     <title>Resources</title>
839     <body>
840    
841     <ul>
842     <li>
843 swift 1.37 <uri link="http://en.wikipedia.org/wiki/Unicode">The Wikipedia entry for
844 neysx 1.1 Unicode</uri>
845     </li>
846     <li>
847 swift 1.37 <uri link="http://en.wikipedia.org/wiki/UTF-8">The Wikipedia entry for
848 neysx 1.1 UTF-8</uri>
849     </li>
850     <li><uri link="http://www.unicode.org">Unicode.org</uri></li>
851     <li><uri link="http://www.utf-8.com">UTF-8.com</uri></li>
852     <li><uri link="http://www.ietf.org/rfc/rfc3629.txt">RFC 3629</uri></li>
853     <li><uri link="http://www.ietf.org/rfc/rfc2277.txt">RFC 2277</uri></li>
854 bennyc 1.11 <li>
855     <uri
856     link="http://www.tbray.org/ongoing/When/200x/2003/04/26/UTF">Characters vs.
857     Bytes</uri>
858     </li>
859 neysx 1.1 </ul>
860    
861     </body>
862     </section>
863     </chapter>
864     </guide>

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