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1 neysx 1.1 <?xml version='1.0' encoding="UTF-8"?>
2 jkt 1.50 <!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/utf-8.xml,v 1.49 2008/10/10 16:03:49 jkt 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 1.50 <version>2.27</version>
29 jkt 1.49 <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 jkt 1.50 You can also substitute <c>LC_CTYPE</c> for <c>LANG</c>. For more information on
266     the categories affected by using <c>LC_CTYPE</c>, please read the <uri
267 nightmorph 1.45 link="http://www.gnu.org/software/libc/manual/html_node/Locale-Categories.html#Locale-Categories">GNU
268     locale page</uri>.
269     </note>
270    
271 bennyc 1.12 <p>
272     Next, the environment must be updated with the change.
273     </p>
274 bennyc 1.10
275 bennyc 1.12 <pre caption="Updating the environment">
276     # <i>env-update</i>
277     >>> Regenerating /etc/ld.so.cache...
278     * Caching service dependencies ...
279 swift 1.13 # <i>source /etc/profile</i>
280 bennyc 1.10 </pre>
281    
282 bennyc 1.12 <p>
283     Now, run <c>locale</c> with no arguments to see if we have the correct
284     variables in our environment:
285     </p>
286    
287     <pre caption="Checking if our new locale is in the environment">
288     # <i>locale</i>
289 jkt 1.50 LANG=en_GB.UTF-8
290 bennyc 1.12 LC_CTYPE="en_GB.UTF-8"
291     LC_NUMERIC="en_GB.UTF-8"
292     LC_TIME="en_GB.UTF-8"
293     LC_COLLATE="en_GB.UTF-8"
294     LC_MONETARY="en_GB.UTF-8"
295     LC_MESSAGES="en_GB.UTF-8"
296     LC_PAPER="en_GB.UTF-8"
297     LC_NAME="en_GB.UTF-8"
298     LC_ADDRESS="en_GB.UTF-8"
299     LC_TELEPHONE="en_GB.UTF-8"
300     LC_MEASUREMENT="en_GB.UTF-8"
301     LC_IDENTIFICATION="en_GB.UTF-8"
302 jkt 1.50 LC_ALL=
303 neysx 1.1 </pre>
304    
305 bennyc 1.10 <p>
306 bennyc 1.12 That's everything. You are now using UTF-8 locales, and the next hurdle is the
307     configuration of the applications you use from day to day.
308 neysx 1.1 </p>
309    
310     </body>
311     </section>
312     </chapter>
313    
314     <chapter>
315     <title>Application Support</title>
316     <section>
317     <body>
318    
319     <p>
320     When Unicode first started gaining momentum in the software world, multibyte
321     character sets were not well suited to languages like C, in which many of the
322     day-to-day programs people use are written. Even today, some programs are not
323     able to handle UTF-8 properly. Fortunately, most are!
324     </p>
325    
326     </body>
327     </section>
328     <section>
329     <title>Filenames, NTFS, and FAT</title>
330     <body>
331    
332     <p>
333     There are several NLS options in the Linux kernel configuration menu, but it is
334     important to not become confused! For the most part, the only thing you need to
335     do is to build UTF-8 NLS support into your kernel, and change the default NLS
336     option to utf8.
337     </p>
338    
339     <pre caption="Kernel configuration steps for UTF-8 NLS">
340     File Systems --&gt;
341     Native Language Support --&gt;
342     (utf8) Default NLS Option
343     &lt;*&gt; NLS UTF8
344     <comment>(Also &lt;*&gt; other character sets that are in use in
345     your FAT filesystems or Joilet CD-ROMs.)</comment>
346     </pre>
347    
348     <p>
349     If you plan on mounting NTFS partitions, you may need to specify an <c>nls=</c>
350 nightmorph 1.40 option with mount. If you plan on mounting FAT partitions, you may need to
351 fox2mike 1.28 specify a <c>codepage=</c> option with mount. Optionally, you can also set a
352     default codepage for FAT in the kernel configuration. Note that the
353     <c>codepage</c> option with mount will override the kernel settings.
354     </p>
355    
356     <pre caption="FAT settings in kernel configuration">
357     File Systems --&gt;
358     DOS/FAT/NT Filesystems --&gt;
359     (437) Default codepage for fat
360     </pre>
361    
362     <p>
363     You should avoid setting <c>Default iocharset for fat</c> to UTF-8, as it is
364     not recommended. Instead, you may want to pass the option utf8=true when
365     mounting your FAT partitions. For further information, see <c>man mount</c> and
366     the kernel documentation at
367     <path>/usr/src/linux/Documentation/filesystems/vfat.txt</path>.
368 neysx 1.1 </p>
369    
370     <p>
371     For changing the encoding of filenames, <c>app-text/convmv</c> can be used.
372     </p>
373    
374     <pre caption="Example usage of convmv">
375     # <i>emerge --ask app-text/convmv</i>
376 fox2mike 1.29 <comment>(Command format)</comment>
377     # <i>convmv -f &lt;current-encoding&gt; -t utf-8 &lt;filename&gt;</i>
378     <comment>(Substitute iso-8859-1 with the charset you are converting
379     from)</comment>
380     # <i>convmv -f iso-8859-1 -t utf-8 filename</i>
381 neysx 1.1 </pre>
382    
383     <p>
384     For changing the <e>contents</e> of files, use the <c>iconv</c> utility,
385     bundled with <c>glibc</c>:
386     </p>
387    
388     <pre caption="Example usage of iconv">
389     <comment>(substitute iso-8859-1 with the charset you are converting from)</comment>
390     <comment>(Check the output is sane)</comment>
391 swift 1.48 # <i>iconv -f iso-8859-1 -t utf-8 filename</i>
392 neysx 1.1 <comment>(Convert a file, you must create another file)</comment>
393     # <i>iconv -f iso-8859-1 -t utf-8 filename > newfile</i>
394     </pre>
395    
396     <p>
397     <c>app-text/recode</c> can also be used for this purpose.
398     </p>
399    
400     </body>
401     </section>
402     <section>
403     <title>The System Console</title>
404     <body>
405    
406     <impo>
407     You need >=sys-apps/baselayout-1.11.9 for Unicode on the console.
408     </impo>
409    
410     <p>
411     To enable UTF-8 on the console, you should edit <path>/etc/rc.conf</path> and
412     set <c>UNICODE="yes"</c>, and also read the comments in that file -- it is
413     important to have a font that has a good range of characters if you plan on
414 nightmorph 1.46 making the most of Unicode. For this to work, make sure you have properly
415     created a Unicode locale as explained in <uri link="#doc_chap1">Chapter
416     1</uri>.
417 neysx 1.1 </p>
418    
419     <p>
420     The <c>KEYMAP</c> variable, set in <path>/etc/conf.d/keymaps</path>, should
421 swift 1.48 have a Unicode keymap specified.
422 neysx 1.1 </p>
423    
424     <pre caption="Example /etc/conf.d/keymaps snippet">
425     <comment>(Change "uk" to your local layout)</comment>
426 fox2mike 1.26 KEYMAP="uk"
427 neysx 1.1 </pre>
428    
429     </body>
430     </section>
431     <section>
432     <title>Ncurses and Slang</title>
433     <body>
434    
435     <note>
436     Ignore any mention of Slang in this section if you do not have it installed or
437     do not use it.
438     </note>
439    
440     <p>
441     It is wise to add <c>unicode</c> to your global USE flags in
442     <path>/etc/make.conf</path>, and then to remerge <c>sys-libs/ncurses</c> and
443 swift 1.30 <c>sys-libs/slang</c> if appropriate. Portage will do this automatically when
444     you update your system:
445 neysx 1.1 </p>
446    
447 swift 1.30 <pre caption="Updating your system">
448     # <i>emerge --update --deep --newuse world</i>
449 neysx 1.1 </pre>
450    
451     <p>
452     We also need to rebuild packages that link to these, now the USE changes have
453 bennyc 1.11 been applied. The tool we use (<c>revdep-rebuild</c>) is part of the
454     <c>gentoolkit</c> package.
455 neysx 1.1 </p>
456    
457     <pre caption="Rebuilding of programs that link to ncurses or slang">
458     # <i>revdep-rebuild --soname libncurses.so.5</i>
459     # <i>revdep-rebuild --soname libslang.so.1</i>
460     </pre>
461    
462     </body>
463     </section>
464     <section>
465     <title>KDE, GNOME and Xfce</title>
466     <body>
467    
468     <p>
469     All of the major desktop environments have full Unicode support, and will
470     require no further setup than what has already been covered in this guide. This
471     is because the underlying graphical toolkits (Qt or GTK+2) are UTF-8 aware.
472     Subsequently, all applications running on top of these toolkits should be
473     UTF-8-aware out of the box.
474     </p>
475    
476     <p>
477     The exceptions to this rule come in Xlib and GTK+1. GTK+1 requires a
478     iso-10646-1 FontSpec in the ~/.gtkrc, for example
479     <c>-misc-fixed-*-*-*-*-*-*-*-*-*-*-iso10646-1</c>. Also, applications using
480     Xlib or Xaw will need to be given a similar FontSpec, otherwise they will not
481     work.
482     </p>
483    
484     <note>
485     If you have a version of the gnome1 control center around, use that instead.
486     Pick any iso10646-1 font from there.
487     </note>
488    
489     <pre caption="Example ~/.gtkrc (for GTK+1) that defines a Unicode compatible font">
490     style "user-font"
491     {
492     fontset="-misc-fixed-*-*-*-*-*-*-*-*-*-*-iso10646-1"
493     }
494     widget_class "*" style "user-font"
495     </pre>
496    
497     <p>
498     If an application has support for both a Qt and GTK+2 GUI, the GTK+2 GUI will
499     generally give better results with Unicode.
500     </p>
501    
502     </body>
503     </section>
504     <section>
505     <title>X11 and Fonts</title>
506     <body>
507    
508 bennyc 1.11 <impo>
509     <c>x11-base/xorg-x11</c> has far better support for Unicode than XFree86
510     and is <e>highly</e> recommended.
511     </impo>
512    
513 neysx 1.1 <p>
514     TrueType fonts have support for Unicode, and most of the fonts that ship with
515     Xorg have impressive character support, although, obviously, not every single
516     glyph available in Unicode has been created for that font. To build fonts
517     (including the Bitstream Vera set) with support for East Asian letters with X,
518     make sure you have the <c>cjk</c> USE flag set. Many other applications utilise
519     this flag, so it may be worthwhile to add it as a permanent USE flag.
520     </p>
521    
522     <p>
523     Also, several font packages in Portage are Unicode aware.
524     </p>
525    
526     <pre caption="Optional: Install some more Unicode-aware fonts">
527     # <i>emerge terminus-font intlfonts freefonts cronyx-fonts corefonts</i>
528     </pre>
529    
530     </body>
531     </section>
532     <section>
533     <title>Window Managers and Terminal Emulators</title>
534     <body>
535    
536     <p>
537 bennyc 1.11 Window managers not built on GTK or Qt generally have very good Unicode
538     support, as they often use the Xft library for handling fonts. If your window
539     manager does not use Xft for fonts, you can still use the FontSpec mentioned in
540     the previous section as a Unicode font.
541 neysx 1.1 </p>
542    
543     <p>
544     Terminal emulators that use Xft and support Unicode are harder to come by.
545     Aside from Konsole and gnome-terminal, the best options in Portage are
546     <c>x11-terms/rxvt-unicode</c>, <c>xfce-extra/terminal</c>,
547 neysx 1.34 <c>gnustep-apps/terminal</c>, <c>x11-terms/mlterm</c>, or plain
548     <c>x11-terms/xterm</c> when built with the <c>unicode</c> USE flag and invoked
549     as <c>uxterm</c>. <c>app-misc/screen</c> supports UTF-8 too, when invoked as
550 rane 1.35 <c>screen -U</c> or the following is put into the <path>~/.screenrc</path>:
551 neysx 1.1 </p>
552    
553     <pre caption="~/.screenrc for UTF-8">
554     defutf8 on
555     </pre>
556    
557     </body>
558     </section>
559     <section>
560     <title>Vim, Emacs, Xemacs and Nano</title>
561     <body>
562    
563     <p>
564 swift 1.48 Vim provides full UTF-8 support, and also has builtin detection of UTF-8 files.
565 swift 1.27 For further information in Vim, use <c>:help mbyte.txt</c>.
566 neysx 1.1 </p>
567    
568     <p>
569 swift 1.27 Emacs 22.x and higher has full UTF-8 support as well. Xemacs 22.x does not
570 swift 1.48 support combining characters yet.
571 swift 1.27 </p>
572    
573     <p>
574 swift 1.48 Lower versions of Emacs and/or Xemacs might require you to install
575 swift 1.27 <c>app-emacs/mule-ucs</c> and/or <c>app-xemacs/mule-ucs</c>
576     and add the following code to your <path>~/.emacs</path> to have support for CJK
577     languages in UTF-8:
578     </p>
579    
580     <pre caption="Emacs CJK UTF-8 support">
581     (require 'un-define)
582     (require 'jisx0213)
583     (set-language-environment "Japanese")
584     (set-default-coding-systems 'utf-8)
585     (set-terminal-coding-system 'utf-8)
586     </pre>
587    
588     <p>
589 nightmorph 1.38 Nano has provided full UTF-8 support since version 1.3.6.
590 neysx 1.1 </p>
591    
592     </body>
593     </section>
594     <section>
595     <title>Shells</title>
596     <body>
597    
598     <p>
599     Currently, <c>bash</c> provides full Unicode support through the GNU readline
600 nightmorph 1.47 library. Z Shell (<c>zsh</c>) offers Unicode support with the <c>unicode</c> USE
601     flag.
602 neysx 1.1 </p>
603    
604     <p>
605     The C shell, <c>tcsh</c> and <c>ksh</c> do not provide UTF-8 support at all.
606     </p>
607    
608     </body>
609     </section>
610     <section>
611     <title>Irssi</title>
612     <body>
613    
614     <p>
615 swift 1.33 Irssi has complete UTF-8 support, although it does require a user
616 cam 1.5 to set an option.
617 neysx 1.1 </p>
618    
619     <pre caption="Enabling UTF-8 in Irssi">
620 nightmorph 1.39 /set term_charset UTF-8
621 neysx 1.1 </pre>
622    
623     <p>
624     For channels where non-ASCII characters are often exchanged in non-UTF-8
625     charsets, the <c>/recode</c> command may be used to convert the characters.
626     Type <c>/help recode</c> for more information.
627     </p>
628    
629     </body>
630     </section>
631     <section>
632     <title>Mutt</title>
633     <body>
634    
635     <p>
636     The Mutt mail user agent has very good Unicode support. To use UTF-8 with Mutt,
637 rane 1.36 you don't need to put anything in your configuration files. Mutt will work
638     under unicode enviroment without modification if all your configuration files
639     (signature included) are UTF-8 encoded.
640 neysx 1.1 </p>
641    
642     <note>
643     You may still see '?' in mail you read with Mutt. This is a result of people
644 bennyc 1.11 using a mail client which does not indicate the used charset. You can't do much
645     about this than to ask them to configure their client correctly.
646 neysx 1.1 </note>
647    
648     <p>
649     Further information is available from the <uri
650 neysx 1.25 link="http://wiki.mutt.org/index.cgi?MuttFaq/Charset">Mutt Wiki</uri>.
651 neysx 1.1 </p>
652    
653     </body>
654     </section>
655     <section>
656 swift 1.14 <title>Man</title>
657     <body>
658    
659     <p>
660 swift 1.48 Man pages are an integral part of any Linux machine. To ensure that any
661     unicode in your man pages render correctly, edit <path>/etc/man.conf</path>
662 swift 1.14 and replace a line as shown below.
663     </p>
664    
665     <pre caption="man.conf changes for Unicode support">
666     <comment>(This is the old line)</comment>
667     NROFF /usr/bin/nroff -Tascii -c -mandoc
668     <comment>(Replace the one above with this)</comment>
669     NROFF /usr/bin/nroff -mandoc -c
670     </pre>
671    
672     </body>
673     </section>
674     <section>
675 fox2mike 1.20 <title>elinks and links</title>
676     <body>
677    
678     <p>
679     These are commonly used text-based browsers, and we shall see how we can enable
680     UTF-8 support on them. On <c>elinks</c> and <c>links</c>, there are two ways to
681     go about this, one using the Setup option from within the browser or editing the
682     config file. To set the option through the browser, open a site with
683     <c>elinks</c> or <c>links</c> and then <c>Alt+S</c> to enter the Setup Menu then
684     select Terminal options, or press <c>T</c>. Scroll down and select the last
685     option <c>UTF-8 I/O</c> by pressing Enter. Then Save and exit the menu. On
686     <c>links</c> you may have to do a repeat <c>Alt+S</c> and then press <c>S</c> to
687     save. The config file option, is shown below.
688     </p>
689    
690     <pre caption="Enabling UTF-8 for elinks/links">
691     <comment>(For elinks, edit /etc/elinks/elinks.conf or ~/.elinks/elinks.conf and
692     add the following line)</comment>
693     set terminal.linux.utf_8_io = 1
694    
695     <comment>(For links, edit ~/.links/links.cfg and add the following
696     line)</comment>
697     terminal "xterm" 0 1 0 us-ascii utf-8
698     </pre>
699    
700     </body>
701     </section>
702     <section>
703 fox2mike 1.41 <title>Samba</title>
704     <body>
705    
706     <p>
707     Samba is a software suite which implements the SMB (Server Message Block)
708     protocol for UNIX systems such as Macs, Linux and FreeBSD. The protocol
709     is also sometimes referred to as the Common Internet File System (CIFS). Samba
710 rane 1.42 also includes the NetBIOS system - used for file sharing over windows networks.
711 fox2mike 1.41 </p>
712    
713     <pre caption="Enabling UTF-8 for Samba">
714     <comment>(Edit /etc/samba/smb.conf and add the following under the [global] section)</comment>
715     dos charset = 1255
716     unix charset = UTF-8
717     display charset = UTF-8
718     </pre>
719    
720     </body>
721     </section>
722     <section>
723 neysx 1.1 <title>Testing it all out</title>
724     <body>
725    
726     <p>
727     There are numerous UTF-8 test websites around. <c>net-www/w3m</c>,
728     <c>net-www/links</c>, <c>net-www/elinks</c>, <c>net-www/lynx</c> and all
729 cam 1.3 Mozilla based browsers (including Firefox) support UTF-8. Konqueror and Opera
730     have full UTF-8 support too.
731 neysx 1.1 </p>
732    
733     <p>
734     When using one of the text-only web browsers, make absolutely sure you are
735     using a Unicode-aware terminal.
736     </p>
737    
738     <p>
739     If you see certain characters displayed as boxes with letters or numbers
740     inside, this means that your font does not have a character for the symbol or
741     glyph that the UTF-8 wants. Instead, it displays a box with the hex code of the
742     UTF-8 symbol.
743     </p>
744    
745     <ul>
746     <li>
747     <uri link="http://www.w3.org/2001/06/utf-8-test/UTF-8-demo.html">A W3C
748     UTF-8 Test Page</uri>
749     </li>
750     <li>
751     <uri link="http://titus.uni-frankfurt.de/indexe.htm?/unicode/unitest.htm">
752     A UTF-8 test page provided by the University of Frankfurt</uri>
753     </li>
754     </ul>
755    
756     </body>
757     </section>
758     <section>
759     <title>Input Methods</title>
760     <body>
761    
762     <p>
763     <e>Dead keys</e> may be used to input characters in X that are not included on
764     your keyboard. These work by pressing your right Alt key (or in some countries,
765     AltGr) and an optional key from the non-alphabetical section of the keyboard to
766     the left of the return key at once, releasing them, and then pressing a letter.
767     The dead key should modify it. Input can be further modified by using the Shift
768     key at the same time as pressing the AltGr and modifier.
769     </p>
770    
771     <p>
772     To enable dead keys in X, you need a layout that supports it. Most European
773     layouts already have dead keys with the default variant. However, this is not
774     true of North American layouts. Although there is a degree of inconsistency
775     between layouts, the easiest solution seems to be to use a layout in the form
776     "en_US" rather than "us", for example. The layout is set in
777     <path>/etc/X11/xorg.conf</path> like so:
778     </p>
779    
780     <pre caption="/etc/X11/xorg.conf snippet">
781     Section "InputDevice"
782     Identifier "Keyboard0"
783     Driver "kbd"
784     Option "XkbLayout" "en_US" <comment># Rather than just "us"</comment>
785     <comment>(Other Xkb options here)</comment>
786     EndSection
787     </pre>
788    
789     <note>
790     The preceding change only needs to be applied if you are using a North American
791     layout, or another layout where dead keys do not seem to be working. European
792     users should have working dead keys as is.
793     </note>
794    
795     <p>
796 bennyc 1.11 This change will come into effect when your X server is restarted. To apply the
797 neysx 1.1 change now, use the <c>setxkbmap</c> tool, for example, <c>setxkbmap en_US</c>.
798     </p>
799    
800     <p>
801     It is probably easiest to describe dead keys with examples. Although the
802 bennyc 1.11 results are locale dependent, the concepts should remain the same regardless of
803 neysx 1.1 locale. The examples contain UTF-8, so to view them you need to either tell
804     your browser to view the page as UTF-8, or have a UTF-8 locale already
805     configured.
806     </p>
807    
808     <p>
809     When I press AltGr and [ at once, release them, and then press a, 'ä' is
810 bennyc 1.11 produced. When I press AltGr and [ at once, and then press e, 'ë' is produced.
811     When I press AltGr and ; at once, 'á' is produced, and when I press AltGr and ;
812     at once, release them, and then press e, 'é' is produced.
813 neysx 1.1 </p>
814    
815     <p>
816     By pressing AltGr, Shift and [ at once, releasing them, and then pressing a, a
817     Scandinavian 'å' is produced. Similarly, when I press AltGr, Shift and [ at
818     once, release <e>only</e> the [, and then press it again, '˚' is produced.
819     Although it looks like one, this (U+02DA) is not the same as a degree symbol
820     (U+00B0). This works for other accents produced by dead keys — AltGr and [,
821     releasing only the [, then pressing it again makes '¨'.
822     </p>
823    
824     <p>
825     AltGr can be used with alphabetical keys alone. For example, AltGr and m, a
826 bennyc 1.12 Greek lower-case letter mu is produced: 'µ'. AltGr and s produce a
827     scharfes s or esszet: 'ß'. As many European users would expect (because
828 swift 1.31 it is marked on their keyboard), AltGr and 4 (or E depending on the keyboard
829     layout) produces a Euro sign, '€'.
830 neysx 1.1 </p>
831    
832     </body>
833     </section>
834     <section>
835     <title>Resources</title>
836     <body>
837    
838     <ul>
839     <li>
840 swift 1.37 <uri link="http://en.wikipedia.org/wiki/Unicode">The Wikipedia entry for
841 neysx 1.1 Unicode</uri>
842     </li>
843     <li>
844 swift 1.37 <uri link="http://en.wikipedia.org/wiki/UTF-8">The Wikipedia entry for
845 neysx 1.1 UTF-8</uri>
846     </li>
847     <li><uri link="http://www.unicode.org">Unicode.org</uri></li>
848     <li><uri link="http://www.utf-8.com">UTF-8.com</uri></li>
849     <li><uri link="http://www.ietf.org/rfc/rfc3629.txt">RFC 3629</uri></li>
850     <li><uri link="http://www.ietf.org/rfc/rfc2277.txt">RFC 2277</uri></li>
851 bennyc 1.11 <li>
852     <uri
853     link="http://www.tbray.org/ongoing/When/200x/2003/04/26/UTF">Characters vs.
854     Bytes</uri>
855     </li>
856 neysx 1.1 </ul>
857    
858     </body>
859     </section>
860     </chapter>
861     </guide>

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