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1 neysx 1.1 <?xml version='1.0' encoding="UTF-8"?>
2 nightmorph 1.45 <!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/utf-8.xml,v 1.44 2006/08/29 10:03:52 rane 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 nightmorph 1.45 <version>2.23</version>
29     <date>2006-10-06</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     UTF-8 locales: <c>LANG</c> (you can override this variable with the
236     <c>LC_ALL</c> setting as well). There are also many different ways to set it;
237     some people prefer to only have a UTF-8 environment for a specific user, in
238     which case they set them in their <path>~/.profile</path> (if you use
239     <c>/bin/sh</c>), <path>~/.bash_profile</path> or <path>~/.bashrc</path> (if you
240     use <c>/bin/bash</c>).
241 swift 1.18 </p>
242    
243     <p>
244 swift 1.17 Others prefer to set the locale globally. One specific circumstance where
245     the author particularly recommends doing this is when
246     <path>/etc/init.d/xdm</path> is in use, because
247 bennyc 1.12 this init script starts the display manager and desktop before any of the
248     aforementioned shell startup files are sourced, and so before any of the
249     variables are in the environment.
250 neysx 1.1 </p>
251    
252 bennyc 1.12 <p>
253     Setting the locale globally should be done using
254 swift 1.15 <path>/etc/env.d/02locale</path>. The file should look something like the
255 bennyc 1.12 following:
256     </p>
257    
258     <pre caption="Demonstration /etc/env.d/02locale">
259     <comment>(As always, change "en_GB.UTF-8" to your locale)</comment>
260 nightmorph 1.45 LANG="en_GB.UTF-8"
261 bennyc 1.12 </pre>
262    
263 nightmorph 1.45 <note>
264     You can also substitute <c>LC_ALL</c> for <c>LANG</c>. This sets your locale
265     for all categories, including numerical and currency values. On a very few
266     systems, it might cause some issues. However, most users should be able to use
267     <c>LC_ALL</c> without problems. For more information on the categories affected
268     by using <c>LC_ALL</c>, please read the <uri
269     link="http://www.gnu.org/software/libc/manual/html_node/Locale-Categories.html#Locale-Categories">GNU
270     locale page</uri>.
271     </note>
272    
273 bennyc 1.12 <p>
274     Next, the environment must be updated with the change.
275     </p>
276 bennyc 1.10
277 bennyc 1.12 <pre caption="Updating the environment">
278     # <i>env-update</i>
279     >>> Regenerating /etc/ld.so.cache...
280     * Caching service dependencies ...
281 swift 1.13 # <i>source /etc/profile</i>
282 bennyc 1.10 </pre>
283    
284 bennyc 1.12 <p>
285     Now, run <c>locale</c> with no arguments to see if we have the correct
286     variables in our environment:
287     </p>
288    
289     <pre caption="Checking if our new locale is in the environment">
290     # <i>locale</i>
291 swift 1.16 LANG=
292 bennyc 1.12 LC_CTYPE="en_GB.UTF-8"
293     LC_NUMERIC="en_GB.UTF-8"
294     LC_TIME="en_GB.UTF-8"
295     LC_COLLATE="en_GB.UTF-8"
296     LC_MONETARY="en_GB.UTF-8"
297     LC_MESSAGES="en_GB.UTF-8"
298     LC_PAPER="en_GB.UTF-8"
299     LC_NAME="en_GB.UTF-8"
300     LC_ADDRESS="en_GB.UTF-8"
301     LC_TELEPHONE="en_GB.UTF-8"
302     LC_MEASUREMENT="en_GB.UTF-8"
303     LC_IDENTIFICATION="en_GB.UTF-8"
304     LC_ALL=en_GB.UTF-8
305 neysx 1.1 </pre>
306    
307 bennyc 1.10 <p>
308 bennyc 1.12 That's everything. You are now using UTF-8 locales, and the next hurdle is the
309     configuration of the applications you use from day to day.
310 neysx 1.1 </p>
311    
312     </body>
313     </section>
314     </chapter>
315    
316     <chapter>
317     <title>Application Support</title>
318     <section>
319     <body>
320    
321     <p>
322     When Unicode first started gaining momentum in the software world, multibyte
323     character sets were not well suited to languages like C, in which many of the
324     day-to-day programs people use are written. Even today, some programs are not
325     able to handle UTF-8 properly. Fortunately, most are!
326     </p>
327    
328     </body>
329     </section>
330     <section>
331     <title>Filenames, NTFS, and FAT</title>
332     <body>
333    
334     <p>
335     There are several NLS options in the Linux kernel configuration menu, but it is
336     important to not become confused! For the most part, the only thing you need to
337     do is to build UTF-8 NLS support into your kernel, and change the default NLS
338     option to utf8.
339     </p>
340    
341     <pre caption="Kernel configuration steps for UTF-8 NLS">
342     File Systems --&gt;
343     Native Language Support --&gt;
344     (utf8) Default NLS Option
345     &lt;*&gt; NLS UTF8
346     <comment>(Also &lt;*&gt; other character sets that are in use in
347     your FAT filesystems or Joilet CD-ROMs.)</comment>
348     </pre>
349    
350     <p>
351     If you plan on mounting NTFS partitions, you may need to specify an <c>nls=</c>
352 nightmorph 1.40 option with mount. If you plan on mounting FAT partitions, you may need to
353 fox2mike 1.28 specify a <c>codepage=</c> option with mount. Optionally, you can also set a
354     default codepage for FAT in the kernel configuration. Note that the
355     <c>codepage</c> option with mount will override the kernel settings.
356     </p>
357    
358     <pre caption="FAT settings in kernel configuration">
359     File Systems --&gt;
360     DOS/FAT/NT Filesystems --&gt;
361     (437) Default codepage for fat
362     </pre>
363    
364     <p>
365     You should avoid setting <c>Default iocharset for fat</c> to UTF-8, as it is
366     not recommended. Instead, you may want to pass the option utf8=true when
367     mounting your FAT partitions. For further information, see <c>man mount</c> and
368     the kernel documentation at
369     <path>/usr/src/linux/Documentation/filesystems/vfat.txt</path>.
370 neysx 1.1 </p>
371    
372     <p>
373     For changing the encoding of filenames, <c>app-text/convmv</c> can be used.
374     </p>
375    
376     <pre caption="Example usage of convmv">
377     # <i>emerge --ask app-text/convmv</i>
378 fox2mike 1.29 <comment>(Command format)</comment>
379     # <i>convmv -f &lt;current-encoding&gt; -t utf-8 &lt;filename&gt;</i>
380     <comment>(Substitute iso-8859-1 with the charset you are converting
381     from)</comment>
382     # <i>convmv -f iso-8859-1 -t utf-8 filename</i>
383 neysx 1.1 </pre>
384    
385     <p>
386     For changing the <e>contents</e> of files, use the <c>iconv</c> utility,
387     bundled with <c>glibc</c>:
388     </p>
389    
390     <pre caption="Example usage of iconv">
391     <comment>(substitute iso-8859-1 with the charset you are converting from)</comment>
392     <comment>(Check the output is sane)</comment>
393     # <i>iconv -f iso-8859-1 -t utf-8 filename</i>
394     <comment>(Convert a file, you must create another file)</comment>
395     # <i>iconv -f iso-8859-1 -t utf-8 filename > newfile</i>
396     </pre>
397    
398     <p>
399     <c>app-text/recode</c> can also be used for this purpose.
400     </p>
401    
402     </body>
403     </section>
404     <section>
405     <title>The System Console</title>
406     <body>
407    
408     <impo>
409     You need >=sys-apps/baselayout-1.11.9 for Unicode on the console.
410     </impo>
411    
412     <p>
413     To enable UTF-8 on the console, you should edit <path>/etc/rc.conf</path> and
414     set <c>UNICODE="yes"</c>, and also read the comments in that file -- it is
415     important to have a font that has a good range of characters if you plan on
416     making the most of Unicode.
417     </p>
418    
419     <p>
420     The <c>KEYMAP</c> variable, set in <path>/etc/conf.d/keymaps</path>, should
421 fox2mike 1.26 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 1.27 Vim provides full UTF-8 support, and also has builtin detection of UTF-8 files.
565     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     support combining characters yet.
571     </p>
572    
573     <p>
574     Lower versions of Emacs and/or Xemacs might require you to install
575     <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     library. Z Shell users are in a somewhat worse position -- no parts of the
601     shell have Unicode support, although there is a concerted effort to add
602     multibyte character set support underway at the moment.
603     </p>
604    
605     <p>
606     The C shell, <c>tcsh</c> and <c>ksh</c> do not provide UTF-8 support at all.
607     </p>
608    
609     </body>
610     </section>
611     <section>
612     <title>Irssi</title>
613     <body>
614    
615     <p>
616 swift 1.33 Irssi has complete UTF-8 support, although it does require a user
617 cam 1.5 to set an option.
618 neysx 1.1 </p>
619    
620     <pre caption="Enabling UTF-8 in Irssi">
621 nightmorph 1.39 /set term_charset UTF-8
622 neysx 1.1 </pre>
623    
624     <p>
625     For channels where non-ASCII characters are often exchanged in non-UTF-8
626     charsets, the <c>/recode</c> command may be used to convert the characters.
627     Type <c>/help recode</c> for more information.
628     </p>
629    
630     </body>
631     </section>
632     <section>
633     <title>Mutt</title>
634     <body>
635    
636     <p>
637     The Mutt mail user agent has very good Unicode support. To use UTF-8 with Mutt,
638 rane 1.36 you don't need to put anything in your configuration files. Mutt will work
639     under unicode enviroment without modification if all your configuration files
640     (signature included) are UTF-8 encoded.
641 neysx 1.1 </p>
642    
643     <note>
644     You may still see '?' in mail you read with Mutt. This is a result of people
645 bennyc 1.11 using a mail client which does not indicate the used charset. You can't do much
646     about this than to ask them to configure their client correctly.
647 neysx 1.1 </note>
648    
649     <p>
650     Further information is available from the <uri
651 neysx 1.25 link="http://wiki.mutt.org/index.cgi?MuttFaq/Charset">Mutt Wiki</uri>.
652 neysx 1.1 </p>
653    
654     </body>
655     </section>
656     <section>
657 swift 1.14 <title>Man</title>
658     <body>
659    
660     <p>
661     Man pages are an integral part of any Linux machine. To ensure that any
662     unicode in your man pages render correctly, edit <path>/etc/man.conf</path>
663     and replace a line as shown below.
664     </p>
665    
666     <pre caption="man.conf changes for Unicode support">
667     <comment>(This is the old line)</comment>
668     NROFF /usr/bin/nroff -Tascii -c -mandoc
669     <comment>(Replace the one above with this)</comment>
670     NROFF /usr/bin/nroff -mandoc -c
671     </pre>
672    
673     </body>
674     </section>
675     <section>
676 fox2mike 1.20 <title>elinks and links</title>
677     <body>
678    
679     <p>
680     These are commonly used text-based browsers, and we shall see how we can enable
681     UTF-8 support on them. On <c>elinks</c> and <c>links</c>, there are two ways to
682     go about this, one using the Setup option from within the browser or editing the
683     config file. To set the option through the browser, open a site with
684     <c>elinks</c> or <c>links</c> and then <c>Alt+S</c> to enter the Setup Menu then
685     select Terminal options, or press <c>T</c>. Scroll down and select the last
686     option <c>UTF-8 I/O</c> by pressing Enter. Then Save and exit the menu. On
687     <c>links</c> you may have to do a repeat <c>Alt+S</c> and then press <c>S</c> to
688     save. The config file option, is shown below.
689     </p>
690    
691     <pre caption="Enabling UTF-8 for elinks/links">
692     <comment>(For elinks, edit /etc/elinks/elinks.conf or ~/.elinks/elinks.conf and
693     add the following line)</comment>
694     set terminal.linux.utf_8_io = 1
695    
696     <comment>(For links, edit ~/.links/links.cfg and add the following
697     line)</comment>
698     terminal "xterm" 0 1 0 us-ascii utf-8
699     </pre>
700    
701     </body>
702     </section>
703     <section>
704 fox2mike 1.41 <title>Samba</title>
705     <body>
706    
707     <p>
708     Samba is a software suite which implements the SMB (Server Message Block)
709     protocol for UNIX systems such as Macs, Linux and FreeBSD. The protocol
710     is also sometimes referred to as the Common Internet File System (CIFS). Samba
711 rane 1.42 also includes the NetBIOS system - used for file sharing over windows networks.
712 fox2mike 1.41 </p>
713    
714     <pre caption="Enabling UTF-8 for Samba">
715     <comment>(Edit /etc/samba/smb.conf and add the following under the [global] section)</comment>
716     dos charset = 1255
717     unix charset = UTF-8
718     display charset = UTF-8
719     </pre>
720    
721     </body>
722     </section>
723     <section>
724 neysx 1.1 <title>Testing it all out</title>
725     <body>
726    
727     <p>
728     There are numerous UTF-8 test websites around. <c>net-www/w3m</c>,
729     <c>net-www/links</c>, <c>net-www/elinks</c>, <c>net-www/lynx</c> and all
730 cam 1.3 Mozilla based browsers (including Firefox) support UTF-8. Konqueror and Opera
731     have full UTF-8 support too.
732 neysx 1.1 </p>
733    
734     <p>
735     When using one of the text-only web browsers, make absolutely sure you are
736     using a Unicode-aware terminal.
737     </p>
738    
739     <p>
740     If you see certain characters displayed as boxes with letters or numbers
741     inside, this means that your font does not have a character for the symbol or
742     glyph that the UTF-8 wants. Instead, it displays a box with the hex code of the
743     UTF-8 symbol.
744     </p>
745    
746     <ul>
747     <li>
748     <uri link="http://www.w3.org/2001/06/utf-8-test/UTF-8-demo.html">A W3C
749     UTF-8 Test Page</uri>
750     </li>
751     <li>
752     <uri link="http://titus.uni-frankfurt.de/indexe.htm?/unicode/unitest.htm">
753     A UTF-8 test page provided by the University of Frankfurt</uri>
754     </li>
755     </ul>
756    
757     </body>
758     </section>
759     <section>
760     <title>Input Methods</title>
761     <body>
762    
763     <p>
764     <e>Dead keys</e> may be used to input characters in X that are not included on
765     your keyboard. These work by pressing your right Alt key (or in some countries,
766     AltGr) and an optional key from the non-alphabetical section of the keyboard to
767     the left of the return key at once, releasing them, and then pressing a letter.
768     The dead key should modify it. Input can be further modified by using the Shift
769     key at the same time as pressing the AltGr and modifier.
770     </p>
771    
772     <p>
773     To enable dead keys in X, you need a layout that supports it. Most European
774     layouts already have dead keys with the default variant. However, this is not
775     true of North American layouts. Although there is a degree of inconsistency
776     between layouts, the easiest solution seems to be to use a layout in the form
777     "en_US" rather than "us", for example. The layout is set in
778     <path>/etc/X11/xorg.conf</path> like so:
779     </p>
780    
781     <pre caption="/etc/X11/xorg.conf snippet">
782     Section "InputDevice"
783     Identifier "Keyboard0"
784     Driver "kbd"
785     Option "XkbLayout" "en_US" <comment># Rather than just "us"</comment>
786     <comment>(Other Xkb options here)</comment>
787     EndSection
788     </pre>
789    
790     <note>
791     The preceding change only needs to be applied if you are using a North American
792     layout, or another layout where dead keys do not seem to be working. European
793     users should have working dead keys as is.
794     </note>
795    
796     <p>
797 bennyc 1.11 This change will come into effect when your X server is restarted. To apply the
798 neysx 1.1 change now, use the <c>setxkbmap</c> tool, for example, <c>setxkbmap en_US</c>.
799     </p>
800    
801     <p>
802     It is probably easiest to describe dead keys with examples. Although the
803 bennyc 1.11 results are locale dependent, the concepts should remain the same regardless of
804 neysx 1.1 locale. The examples contain UTF-8, so to view them you need to either tell
805     your browser to view the page as UTF-8, or have a UTF-8 locale already
806     configured.
807     </p>
808    
809     <p>
810     When I press AltGr and [ at once, release them, and then press a, 'ä' is
811 bennyc 1.11 produced. When I press AltGr and [ at once, and then press e, 'ë' is produced.
812     When I press AltGr and ; at once, 'á' is produced, and when I press AltGr and ;
813     at once, release them, and then press e, 'é' is produced.
814 neysx 1.1 </p>
815    
816     <p>
817     By pressing AltGr, Shift and [ at once, releasing them, and then pressing a, a
818     Scandinavian 'å' is produced. Similarly, when I press AltGr, Shift and [ at
819     once, release <e>only</e> the [, and then press it again, '˚' is produced.
820     Although it looks like one, this (U+02DA) is not the same as a degree symbol
821     (U+00B0). This works for other accents produced by dead keys — AltGr and [,
822     releasing only the [, then pressing it again makes '¨'.
823     </p>
824    
825     <p>
826     AltGr can be used with alphabetical keys alone. For example, AltGr and m, a
827 bennyc 1.12 Greek lower-case letter mu is produced: 'µ'. AltGr and s produce a
828     scharfes s or esszet: 'ß'. As many European users would expect (because
829 swift 1.31 it is marked on their keyboard), AltGr and 4 (or E depending on the keyboard
830     layout) produces a Euro sign, '€'.
831 neysx 1.1 </p>
832    
833     </body>
834     </section>
835     <section>
836     <title>Resources</title>
837     <body>
838    
839     <ul>
840     <li>
841 swift 1.37 <uri link="http://en.wikipedia.org/wiki/Unicode">The Wikipedia entry for
842 neysx 1.1 Unicode</uri>
843     </li>
844     <li>
845 swift 1.37 <uri link="http://en.wikipedia.org/wiki/UTF-8">The Wikipedia entry for
846 neysx 1.1 UTF-8</uri>
847     </li>
848     <li><uri link="http://www.unicode.org">Unicode.org</uri></li>
849     <li><uri link="http://www.utf-8.com">UTF-8.com</uri></li>
850     <li><uri link="http://www.ietf.org/rfc/rfc3629.txt">RFC 3629</uri></li>
851     <li><uri link="http://www.ietf.org/rfc/rfc2277.txt">RFC 2277</uri></li>
852 bennyc 1.11 <li>
853     <uri
854     link="http://www.tbray.org/ongoing/When/200x/2003/04/26/UTF">Characters vs.
855     Bytes</uri>
856     </li>
857 neysx 1.1 </ul>
858    
859     </body>
860     </section>
861     </chapter>
862     </guide>

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