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1 neysx 1.1 <?xml version='1.0' encoding="UTF-8"?>
2 nightmorph 1.47 <!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/utf-8.xml,v 1.46 2007/01/10 07:29:00 nightmorph 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 1.47 <version>2.25</version>
29     <date>2007-04-17</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 nightmorph 1.46 making the most of Unicode. For this to work, make sure you have properly
417     created a Unicode locale as explained in <uri link="#doc_chap1">Chapter
418     1</uri>.
419 neysx 1.1 </p>
420    
421     <p>
422     The <c>KEYMAP</c> variable, set in <path>/etc/conf.d/keymaps</path>, should
423 fox2mike 1.26 have a Unicode keymap specified.
424 neysx 1.1 </p>
425    
426     <pre caption="Example /etc/conf.d/keymaps snippet">
427     <comment>(Change "uk" to your local layout)</comment>
428 fox2mike 1.26 KEYMAP="uk"
429 neysx 1.1 </pre>
430    
431     </body>
432     </section>
433     <section>
434     <title>Ncurses and Slang</title>
435     <body>
436    
437     <note>
438     Ignore any mention of Slang in this section if you do not have it installed or
439     do not use it.
440     </note>
441    
442     <p>
443     It is wise to add <c>unicode</c> to your global USE flags in
444     <path>/etc/make.conf</path>, and then to remerge <c>sys-libs/ncurses</c> and
445 swift 1.30 <c>sys-libs/slang</c> if appropriate. Portage will do this automatically when
446     you update your system:
447 neysx 1.1 </p>
448    
449 swift 1.30 <pre caption="Updating your system">
450     # <i>emerge --update --deep --newuse world</i>
451 neysx 1.1 </pre>
452    
453     <p>
454     We also need to rebuild packages that link to these, now the USE changes have
455 bennyc 1.11 been applied. The tool we use (<c>revdep-rebuild</c>) is part of the
456     <c>gentoolkit</c> package.
457 neysx 1.1 </p>
458    
459     <pre caption="Rebuilding of programs that link to ncurses or slang">
460     # <i>revdep-rebuild --soname libncurses.so.5</i>
461     # <i>revdep-rebuild --soname libslang.so.1</i>
462     </pre>
463    
464     </body>
465     </section>
466     <section>
467     <title>KDE, GNOME and Xfce</title>
468     <body>
469    
470     <p>
471     All of the major desktop environments have full Unicode support, and will
472     require no further setup than what has already been covered in this guide. This
473     is because the underlying graphical toolkits (Qt or GTK+2) are UTF-8 aware.
474     Subsequently, all applications running on top of these toolkits should be
475     UTF-8-aware out of the box.
476     </p>
477    
478     <p>
479     The exceptions to this rule come in Xlib and GTK+1. GTK+1 requires a
480     iso-10646-1 FontSpec in the ~/.gtkrc, for example
481     <c>-misc-fixed-*-*-*-*-*-*-*-*-*-*-iso10646-1</c>. Also, applications using
482     Xlib or Xaw will need to be given a similar FontSpec, otherwise they will not
483     work.
484     </p>
485    
486     <note>
487     If you have a version of the gnome1 control center around, use that instead.
488     Pick any iso10646-1 font from there.
489     </note>
490    
491     <pre caption="Example ~/.gtkrc (for GTK+1) that defines a Unicode compatible font">
492     style "user-font"
493     {
494     fontset="-misc-fixed-*-*-*-*-*-*-*-*-*-*-iso10646-1"
495     }
496     widget_class "*" style "user-font"
497     </pre>
498    
499     <p>
500     If an application has support for both a Qt and GTK+2 GUI, the GTK+2 GUI will
501     generally give better results with Unicode.
502     </p>
503    
504     </body>
505     </section>
506     <section>
507     <title>X11 and Fonts</title>
508     <body>
509    
510 bennyc 1.11 <impo>
511     <c>x11-base/xorg-x11</c> has far better support for Unicode than XFree86
512     and is <e>highly</e> recommended.
513     </impo>
514    
515 neysx 1.1 <p>
516     TrueType fonts have support for Unicode, and most of the fonts that ship with
517     Xorg have impressive character support, although, obviously, not every single
518     glyph available in Unicode has been created for that font. To build fonts
519     (including the Bitstream Vera set) with support for East Asian letters with X,
520     make sure you have the <c>cjk</c> USE flag set. Many other applications utilise
521     this flag, so it may be worthwhile to add it as a permanent USE flag.
522     </p>
523    
524     <p>
525     Also, several font packages in Portage are Unicode aware.
526     </p>
527    
528     <pre caption="Optional: Install some more Unicode-aware fonts">
529     # <i>emerge terminus-font intlfonts freefonts cronyx-fonts corefonts</i>
530     </pre>
531    
532     </body>
533     </section>
534     <section>
535     <title>Window Managers and Terminal Emulators</title>
536     <body>
537    
538     <p>
539 bennyc 1.11 Window managers not built on GTK or Qt generally have very good Unicode
540     support, as they often use the Xft library for handling fonts. If your window
541     manager does not use Xft for fonts, you can still use the FontSpec mentioned in
542     the previous section as a Unicode font.
543 neysx 1.1 </p>
544    
545     <p>
546     Terminal emulators that use Xft and support Unicode are harder to come by.
547     Aside from Konsole and gnome-terminal, the best options in Portage are
548     <c>x11-terms/rxvt-unicode</c>, <c>xfce-extra/terminal</c>,
549 neysx 1.34 <c>gnustep-apps/terminal</c>, <c>x11-terms/mlterm</c>, or plain
550     <c>x11-terms/xterm</c> when built with the <c>unicode</c> USE flag and invoked
551     as <c>uxterm</c>. <c>app-misc/screen</c> supports UTF-8 too, when invoked as
552 rane 1.35 <c>screen -U</c> or the following is put into the <path>~/.screenrc</path>:
553 neysx 1.1 </p>
554    
555     <pre caption="~/.screenrc for UTF-8">
556     defutf8 on
557     </pre>
558    
559     </body>
560     </section>
561     <section>
562     <title>Vim, Emacs, Xemacs and Nano</title>
563     <body>
564    
565     <p>
566 swift 1.27 Vim provides full UTF-8 support, and also has builtin detection of UTF-8 files.
567     For further information in Vim, use <c>:help mbyte.txt</c>.
568 neysx 1.1 </p>
569    
570     <p>
571 swift 1.27 Emacs 22.x and higher has full UTF-8 support as well. Xemacs 22.x does not
572     support combining characters yet.
573     </p>
574    
575     <p>
576     Lower versions of Emacs and/or Xemacs might require you to install
577     <c>app-emacs/mule-ucs</c> and/or <c>app-xemacs/mule-ucs</c>
578     and add the following code to your <path>~/.emacs</path> to have support for CJK
579     languages in UTF-8:
580     </p>
581    
582     <pre caption="Emacs CJK UTF-8 support">
583     (require 'un-define)
584     (require 'jisx0213)
585     (set-language-environment "Japanese")
586     (set-default-coding-systems 'utf-8)
587     (set-terminal-coding-system 'utf-8)
588     </pre>
589    
590     <p>
591 nightmorph 1.38 Nano has provided full UTF-8 support since version 1.3.6.
592 neysx 1.1 </p>
593    
594     </body>
595     </section>
596     <section>
597     <title>Shells</title>
598     <body>
599    
600     <p>
601     Currently, <c>bash</c> provides full Unicode support through the GNU readline
602 nightmorph 1.47 library. Z Shell (<c>zsh</c>) offers Unicode support with the <c>unicode</c> USE
603     flag.
604 neysx 1.1 </p>
605    
606     <p>
607     The C shell, <c>tcsh</c> and <c>ksh</c> do not provide UTF-8 support at all.
608     </p>
609    
610     </body>
611     </section>
612     <section>
613     <title>Irssi</title>
614     <body>
615    
616     <p>
617 swift 1.33 Irssi has complete UTF-8 support, although it does require a user
618 cam 1.5 to set an option.
619 neysx 1.1 </p>
620    
621     <pre caption="Enabling UTF-8 in Irssi">
622 nightmorph 1.39 /set term_charset UTF-8
623 neysx 1.1 </pre>
624    
625     <p>
626     For channels where non-ASCII characters are often exchanged in non-UTF-8
627     charsets, the <c>/recode</c> command may be used to convert the characters.
628     Type <c>/help recode</c> for more information.
629     </p>
630    
631     </body>
632     </section>
633     <section>
634     <title>Mutt</title>
635     <body>
636    
637     <p>
638     The Mutt mail user agent has very good Unicode support. To use UTF-8 with Mutt,
639 rane 1.36 you don't need to put anything in your configuration files. Mutt will work
640     under unicode enviroment without modification if all your configuration files
641     (signature included) are UTF-8 encoded.
642 neysx 1.1 </p>
643    
644     <note>
645     You may still see '?' in mail you read with Mutt. This is a result of people
646 bennyc 1.11 using a mail client which does not indicate the used charset. You can't do much
647     about this than to ask them to configure their client correctly.
648 neysx 1.1 </note>
649    
650     <p>
651     Further information is available from the <uri
652 neysx 1.25 link="http://wiki.mutt.org/index.cgi?MuttFaq/Charset">Mutt Wiki</uri>.
653 neysx 1.1 </p>
654    
655     </body>
656     </section>
657     <section>
658 swift 1.14 <title>Man</title>
659     <body>
660    
661     <p>
662     Man pages are an integral part of any Linux machine. To ensure that any
663     unicode in your man pages render correctly, edit <path>/etc/man.conf</path>
664     and replace a line as shown below.
665     </p>
666    
667     <pre caption="man.conf changes for Unicode support">
668     <comment>(This is the old line)</comment>
669     NROFF /usr/bin/nroff -Tascii -c -mandoc
670     <comment>(Replace the one above with this)</comment>
671     NROFF /usr/bin/nroff -mandoc -c
672     </pre>
673    
674     </body>
675     </section>
676     <section>
677 fox2mike 1.20 <title>elinks and links</title>
678     <body>
679    
680     <p>
681     These are commonly used text-based browsers, and we shall see how we can enable
682     UTF-8 support on them. On <c>elinks</c> and <c>links</c>, there are two ways to
683     go about this, one using the Setup option from within the browser or editing the
684     config file. To set the option through the browser, open a site with
685     <c>elinks</c> or <c>links</c> and then <c>Alt+S</c> to enter the Setup Menu then
686     select Terminal options, or press <c>T</c>. Scroll down and select the last
687     option <c>UTF-8 I/O</c> by pressing Enter. Then Save and exit the menu. On
688     <c>links</c> you may have to do a repeat <c>Alt+S</c> and then press <c>S</c> to
689     save. The config file option, is shown below.
690     </p>
691    
692     <pre caption="Enabling UTF-8 for elinks/links">
693     <comment>(For elinks, edit /etc/elinks/elinks.conf or ~/.elinks/elinks.conf and
694     add the following line)</comment>
695     set terminal.linux.utf_8_io = 1
696    
697     <comment>(For links, edit ~/.links/links.cfg and add the following
698     line)</comment>
699     terminal "xterm" 0 1 0 us-ascii utf-8
700     </pre>
701    
702     </body>
703     </section>
704     <section>
705 fox2mike 1.41 <title>Samba</title>
706     <body>
707    
708     <p>
709     Samba is a software suite which implements the SMB (Server Message Block)
710     protocol for UNIX systems such as Macs, Linux and FreeBSD. The protocol
711     is also sometimes referred to as the Common Internet File System (CIFS). Samba
712 rane 1.42 also includes the NetBIOS system - used for file sharing over windows networks.
713 fox2mike 1.41 </p>
714    
715     <pre caption="Enabling UTF-8 for Samba">
716     <comment>(Edit /etc/samba/smb.conf and add the following under the [global] section)</comment>
717     dos charset = 1255
718     unix charset = UTF-8
719     display charset = UTF-8
720     </pre>
721    
722     </body>
723     </section>
724     <section>
725 neysx 1.1 <title>Testing it all out</title>
726     <body>
727    
728     <p>
729     There are numerous UTF-8 test websites around. <c>net-www/w3m</c>,
730     <c>net-www/links</c>, <c>net-www/elinks</c>, <c>net-www/lynx</c> and all
731 cam 1.3 Mozilla based browsers (including Firefox) support UTF-8. Konqueror and Opera
732     have full UTF-8 support too.
733 neysx 1.1 </p>
734    
735     <p>
736     When using one of the text-only web browsers, make absolutely sure you are
737     using a Unicode-aware terminal.
738     </p>
739    
740     <p>
741     If you see certain characters displayed as boxes with letters or numbers
742     inside, this means that your font does not have a character for the symbol or
743     glyph that the UTF-8 wants. Instead, it displays a box with the hex code of the
744     UTF-8 symbol.
745     </p>
746    
747     <ul>
748     <li>
749     <uri link="http://www.w3.org/2001/06/utf-8-test/UTF-8-demo.html">A W3C
750     UTF-8 Test Page</uri>
751     </li>
752     <li>
753     <uri link="http://titus.uni-frankfurt.de/indexe.htm?/unicode/unitest.htm">
754     A UTF-8 test page provided by the University of Frankfurt</uri>
755     </li>
756     </ul>
757    
758     </body>
759     </section>
760     <section>
761     <title>Input Methods</title>
762     <body>
763    
764     <p>
765     <e>Dead keys</e> may be used to input characters in X that are not included on
766     your keyboard. These work by pressing your right Alt key (or in some countries,
767     AltGr) and an optional key from the non-alphabetical section of the keyboard to
768     the left of the return key at once, releasing them, and then pressing a letter.
769     The dead key should modify it. Input can be further modified by using the Shift
770     key at the same time as pressing the AltGr and modifier.
771     </p>
772    
773     <p>
774     To enable dead keys in X, you need a layout that supports it. Most European
775     layouts already have dead keys with the default variant. However, this is not
776     true of North American layouts. Although there is a degree of inconsistency
777     between layouts, the easiest solution seems to be to use a layout in the form
778     "en_US" rather than "us", for example. The layout is set in
779     <path>/etc/X11/xorg.conf</path> like so:
780     </p>
781    
782     <pre caption="/etc/X11/xorg.conf snippet">
783     Section "InputDevice"
784     Identifier "Keyboard0"
785     Driver "kbd"
786     Option "XkbLayout" "en_US" <comment># Rather than just "us"</comment>
787     <comment>(Other Xkb options here)</comment>
788     EndSection
789     </pre>
790    
791     <note>
792     The preceding change only needs to be applied if you are using a North American
793     layout, or another layout where dead keys do not seem to be working. European
794     users should have working dead keys as is.
795     </note>
796    
797     <p>
798 bennyc 1.11 This change will come into effect when your X server is restarted. To apply the
799 neysx 1.1 change now, use the <c>setxkbmap</c> tool, for example, <c>setxkbmap en_US</c>.
800     </p>
801    
802     <p>
803     It is probably easiest to describe dead keys with examples. Although the
804 bennyc 1.11 results are locale dependent, the concepts should remain the same regardless of
805 neysx 1.1 locale. The examples contain UTF-8, so to view them you need to either tell
806     your browser to view the page as UTF-8, or have a UTF-8 locale already
807     configured.
808     </p>
809    
810     <p>
811     When I press AltGr and [ at once, release them, and then press a, 'ä' is
812 bennyc 1.11 produced. When I press AltGr and [ at once, and then press e, 'ë' is produced.
813     When I press AltGr and ; at once, 'á' is produced, and when I press AltGr and ;
814     at once, release them, and then press e, 'é' is produced.
815 neysx 1.1 </p>
816    
817     <p>
818     By pressing AltGr, Shift and [ at once, releasing them, and then pressing a, a
819     Scandinavian 'å' is produced. Similarly, when I press AltGr, Shift and [ at
820     once, release <e>only</e> the [, and then press it again, '˚' is produced.
821     Although it looks like one, this (U+02DA) is not the same as a degree symbol
822     (U+00B0). This works for other accents produced by dead keys — AltGr and [,
823     releasing only the [, then pressing it again makes '¨'.
824     </p>
825    
826     <p>
827     AltGr can be used with alphabetical keys alone. For example, AltGr and m, a
828 bennyc 1.12 Greek lower-case letter mu is produced: 'µ'. AltGr and s produce a
829     scharfes s or esszet: 'ß'. As many European users would expect (because
830 swift 1.31 it is marked on their keyboard), AltGr and 4 (or E depending on the keyboard
831     layout) produces a Euro sign, '€'.
832 neysx 1.1 </p>
833    
834     </body>
835     </section>
836     <section>
837     <title>Resources</title>
838     <body>
839    
840     <ul>
841     <li>
842 swift 1.37 <uri link="http://en.wikipedia.org/wiki/Unicode">The Wikipedia entry for
843 neysx 1.1 Unicode</uri>
844     </li>
845     <li>
846 swift 1.37 <uri link="http://en.wikipedia.org/wiki/UTF-8">The Wikipedia entry for
847 neysx 1.1 UTF-8</uri>
848     </li>
849     <li><uri link="http://www.unicode.org">Unicode.org</uri></li>
850     <li><uri link="http://www.utf-8.com">UTF-8.com</uri></li>
851     <li><uri link="http://www.ietf.org/rfc/rfc3629.txt">RFC 3629</uri></li>
852     <li><uri link="http://www.ietf.org/rfc/rfc2277.txt">RFC 2277</uri></li>
853 bennyc 1.11 <li>
854     <uri
855     link="http://www.tbray.org/ongoing/When/200x/2003/04/26/UTF">Characters vs.
856     Bytes</uri>
857     </li>
858 neysx 1.1 </ul>
859    
860     </body>
861     </section>
862     </chapter>
863     </guide>

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