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1 <?xml version='1.0' encoding="UTF-8"?>
2 <!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/utf-8.xml,v 1.6 2005/03/17 07:23:54 swift Exp $ -->
3 <!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
15 <abstract>
16 This guide shows you how to set up and use the UTF-8 Unicode character set with
17 your Gentoo Linux system, after explaining the benefits of Unicode and more
18 specifically UTF-8.
19 </abstract>
20
21 <license />
22
23 <version>1.6</version>
24 <date>2005-03-25</date>
25
26 <chapter>
27 <title>Character Encodings</title>
28 <section>
29 <title>What is a Character Encoding?</title>
30 <body>
31
32 <p>
33 Computers do not understand text themselves. Instead, every character is
34 represented by a number. Traditionally, each set of numbers used to represent
35 alphabets and characters (known as a coding system, encoding or character set)
36 was limited in size due to limitations in computer hardware.
37 </p>
38
39 </body>
40 </section>
41 <section>
42 <title>The History of Character Encodings</title>
43 <body>
44
45 <p>
46 The most common (or at least the most widely accepted) character set is
47 <b>ASCII</b> (American Standard Code for Information Interchange). It is widely
48 held that ASCII is the most successful software standard ever. Modern ASCII
49 was standardised in 1986 (ANSI X3.4, RFC 20, ISO/IEC 646:1991, ECMA-6) by the
50 American National Standards Institute.
51 </p>
52
53 <p>
54 ASCII is strictly seven-bit, meaning that it uses bit patterns representable
55 with seven binary digits, which provides a range of 0 to 127 in decimal. These
56 include 32 non-visible control characters, most between 0 and 31, with the
57 final control character, DEL or delete at 127. Characters 32 to 126 are
58 visible characters: a space, punctuation marks, Latin letters and numbers.
59 </p>
60
61 <p>
62 The eighth bit in ASCII was originally used as a parity bit for error checking.
63 If this is not desired, it is left as 0. This means that, with ASCII, each
64 character is represented by a single byte.
65 </p>
66
67 <p>
68 Although ASCII was enough for communication in modern English, in other
69 European languages that include accented characters, things were not so easy.
70 The ISO 8859 standards were developed to meet these needs. They were backwards
71 compatible with ASCII, but instead of leaving the eighth bit blank, they used
72 it to allow another 127 characters in each encoding. ISO 8859's limitations
73 soon came to light, and there are currently 15 variants of the ISO 8859
74 standard (8859-1 through to 8859-15). Outside of the ASCII-compatible byte
75 range of these character sets, there is often conflict between the letters
76 represented by each byte. To complicate interoperability between character
77 encodings further, Windows-1252 is used in some versions of Microsoft Windows
78 instead for Western European languages. This is a superset of ISO 8859-1,
79 however it is different in several ways. These sets do all retain ASCII
80 compatibility, however.
81 </p>
82
83 <p>
84 The necessary development of completely different single-byte encodings for
85 non-Latin alphabets, such as EUC (Extended Unix Coding) which is used for
86 Japanese and Korean (and to a lesser extent Chinese) created more confusion,
87 while other operating systems still used different character sets for the same
88 languages, for example, Shift-JIS and ISO-2022-JP. Users wishing to view
89 cyrillic glyphs had to choose between KOI8-R for Russian and Bulgarian or
90 KOI8-U for Ukrainian, as well as all the other cyrillic encodings such as the
91 unsuccessful ISO 8859-5, and the common Windows-1251 set. All of these
92 character sets broke most compatibility with ASCII (although KOI8 encodings
93 place cyrillic characters in Latin order, so in case the eighth bit is
94 stripped, text is still decipherable on an ASCII terminal through case-reversed
95 transliteration.)
96 </p>
97
98 <p>
99 This has led to confusion, and also to an almost total inability for
100 multilingual communication, especially across different alphabets. Enter
101 Unicode.
102 </p>
103
104 </body>
105 </section>
106 <section>
107 <title>What is Unicode?</title>
108 <body>
109
110 <p>
111 Unicode throws away the traditional single-byte limit of character sets, and
112 even with two bytes per-character this allows a maximum 65,536 characters.
113 Although this number is extremely high when compared to seven-bit and eight-bit
114 encodings, it is still not enough for a character set designed to be used for
115 symbols and scripts used only by scholars, and symbols that are only used in
116 mathematics and other specialised fields.
117 </p>
118
119 <p>
120 Unicode has been mapped in many different ways, but the two most common are
121 <b>UTF</b> (Unicode Transformation Format) and <b>UCS</b> (Universal Character
122 Set). A number after UTF indicates the number of bits in one unit, while the
123 number after UCS indicates the number of bytes. UTF-8 has become the most
124 widespread means for the interchange of Unicode text as a result of its
125 eight-bit clean nature, and it is the subject of this document.
126 </p>
127
128 </body>
129 </section>
130 <section>
131 <title>UTF-8</title>
132 <body>
133
134 <p>
135 UTF-8 is a variable-length character encoding, which in this instance means
136 that it uses 1 to 4 bytes per symbol. So, the first UTF-8 byte is used for
137 encoding ASCII, giving the character set full backwards compatibility with
138 ASCII. UTF-8 means that ASCII and Latin characters are interchangeable with
139 little increase in the size of the data, because only the first bit is used.
140 Users of Eastern alphabets such as Japanese, who have been assigned a higher
141 byte range are unhappy, as this results in as much as a 50% redundancy in their
142 data.
143 </p>
144
145 </body>
146 </section>
147 <section>
148 <title>What UTF-8 Can Do for You</title>
149 <body>
150
151 <p>
152 UTF-8 allows you to work in a standards-compliant and internationally accepted
153 multilingual environment, with a comparitively low data redundancy. UTF-8 is
154 the preferred way for transmitting non-ASCII characters over the Internet,
155 through Email, IRC or almost any other medium. Despite this, many people regard
156 UTF-8 in online communication as abusive. It is always best to be aware of the
157 attitude towards UTF-8 in a specific channel, mailing list or Usenet group
158 before using <e>non-ASCII</e> UTF-8.
159 </p>
160
161 </body>
162 </section>
163 </chapter>
164
165 <chapter>
166 <title>Setting up UTF-8 with Gentoo Linux</title>
167 <section>
168 <title>Finding or Creating UTF-8 Locales</title>
169 <body>
170
171 <p>
172 Now that you understand the principles behind Unicode, you're ready to start
173 using UTF-8 with your system.
174 </p>
175
176 <p>
177 The preliminary requirement for UTF-8 is to have a version of glibc installed
178 that has national language support. The recommend means to do this is the
179 <path>/etc/locales.build</path> file in combination with the <c>userlocales</c>
180 USE flag. It is beyond the scope of this document to explain the usage of this
181 file though, luckily, the usage of this file is well documented in the comments
182 within it. It is also explained in the <uri
183 link="/doc/en/guide-localization.xml#doc_chap3_sect3"> Gentoo Localisation
184 Guide</uri>.
185 </p>
186
187 <p>
188 Next, we'll need to decide whether a UTF-8 locale is already available for our
189 language, or whether we need to create one.
190 </p>
191
192 <pre caption="Checking for an existing UTF-8 locale">
193 <comment>(Replace "en_GB" with your desired locale setting)</comment>
194 # <i>locale -a | grep 'en_GB'</i>
195 en_GB
196 en_GB.utf8
197 </pre>
198
199 <p>
200 From the output of this command line, we need to take the result with a suffix
201 similar to <c>.utf8</c>. If there is no result with a suffix similar to
202 <c>.utf8</c>, we need to create a UTF-8 compatible locale.
203 </p>
204
205 <note>
206 Only execute the following code listing if you do not have a UTF-8 locale
207 available for your language.
208 </note>
209
210 <pre caption="Creating a UTF-8 locale">
211 <comment>(Replace "en_GB" with your desired locale setting)</comment>
212 # <i>localedef -i en_GB -f UTF-8 en_GB.utf8</i>
213 </pre>
214
215 <p>
216 Another way to include a UTF-8 locale is to add it to the
217 <path>/etc/locales.build</path> file and rebuild <c>glibc</c> with the
218 <c>userlocales</c> USE flag set.
219 </p>
220
221 <pre caption="Line in /etc/locales.build">
222 en_GB.UTF-8/UTF-8
223 </pre>
224
225 </body>
226 </section>
227 <section>
228 <title>Setting the Locale</title>
229 <body>
230
231 <p>
232 Although by now you might be determined to use UTF-8 system wide, the author
233 does not recommend setting UTF-8 for the root user. Instead, it is best to set
234 the locale in your user's <path>~/.profile</path> (or, if you are using a C
235 shell, <path>~/.login</path>).
236 </p>
237
238 <note>
239 If you are not sure which file to use, use <path>~/.profile</path>. Also, if
240 you are unsure which code listing to use, use the Bourne version.
241 </note>
242
243 <pre caption="Setting the locale with environment variables (Bourne version)">
244 export LANG="en_GB.utf8"
245 export LC_ALL="en_GB.utf8"
246 </pre>
247
248 <pre caption="Setting the locale with environment variables (C shell version)">
249 setenv LANG "en_GB.utf8"
250 setenv LC_ALL "en_GB.utf8"
251 </pre>
252
253 <p>
254 Now, logout and back in to apply the change. We want these environment
255 variables in our entire environment, so it is best to logout and back in, or at
256 the very least to source <path>~/.profile</path> or <path>~/.login</path> in
257 the console from which you have started other processes.
258 </p>
259
260 </body>
261 </section>
262 </chapter>
263
264 <chapter>
265 <title>Application Support</title>
266 <section>
267 <body>
268
269 <p>
270 When Unicode first started gaining momentum in the software world, multibyte
271 character sets were not well suited to languages like C, in which many of the
272 day-to-day programs people use are written. Even today, some programs are not
273 able to handle UTF-8 properly. Fortunately, most are!
274 </p>
275
276 </body>
277 </section>
278 <section>
279 <title>Filenames, NTFS, and FAT</title>
280 <body>
281
282 <p>
283 There are several NLS options in the Linux kernel configuration menu, but it is
284 important to not become confused! For the most part, the only thing you need to
285 do is to build UTF-8 NLS support into your kernel, and change the default NLS
286 option to utf8.
287 </p>
288
289 <pre caption="Kernel configuration steps for UTF-8 NLS">
290 File Systems --&gt;
291 Native Language Support --&gt;
292 (utf8) Default NLS Option
293 &lt;*&gt; NLS UTF8
294 <comment>(Also &lt;*&gt; other character sets that are in use in
295 your FAT filesystems or Joilet CD-ROMs.)</comment>
296 </pre>
297
298 <p>
299 If you plan on mounting NTFS partitions, you may need to specify an <c>nls=</c>
300 option with mount. For more information, see <c>man mount</c>.
301 </p>
302
303 <p>
304 For changing the encoding of filenames, <c>app-text/convmv</c> can be used.
305 </p>
306
307 <pre caption="Example usage of convmv">
308 # <i>emerge --ask app-text/convmv</i>
309 # <i>convmv -f current-encoding -t utf-8 filename</i>
310 </pre>
311
312 <p>
313 For changing the <e>contents</e> of files, use the <c>iconv</c> utility,
314 bundled with <c>glibc</c>:
315 </p>
316
317 <pre caption="Example usage of iconv">
318 <comment>(substitute iso-8859-1 with the charset you are converting from)</comment>
319 <comment>(Check the output is sane)</comment>
320 # <i>iconv -f iso-8859-1 -t utf-8 filename</i>
321 <comment>(Convert a file, you must create another file)</comment>
322 # <i>iconv -f iso-8859-1 -t utf-8 filename > newfile</i>
323 </pre>
324
325 <p>
326 <c>app-text/recode</c> can also be used for this purpose.
327 </p>
328
329 </body>
330 </section>
331 <section>
332 <title>The System Console</title>
333 <body>
334
335 <impo>
336 You need >=sys-apps/baselayout-1.11.9 for Unicode on the console.
337 </impo>
338
339 <p>
340 To enable UTF-8 on the console, you should edit <path>/etc/rc.conf</path> and
341 set <c>UNICODE="yes"</c>, and also read the comments in that file -- it is
342 important to have a font that has a good range of characters if you plan on
343 making the most of Unicode.
344 </p>
345
346 <p>
347 The <c>KEYMAP</c> variable, set in <path>/etc/conf.d/keymaps</path>, should
348 have a Unicode keymap specified. To do this, simply prepend the keymap already
349 specified there with -u.
350 </p>
351
352 <pre caption="Example /etc/conf.d/keymaps snippet">
353 <comment>(Change "uk" to your local layout)</comment>
354 KEYMAP="-u uk"
355 </pre>
356
357 </body>
358 </section>
359 <section>
360 <title>Ncurses and Slang</title>
361 <body>
362
363 <note>
364 Ignore any mention of Slang in this section if you do not have it installed or
365 do not use it.
366 </note>
367
368 <p>
369 It is wise to add <c>unicode</c> to your global USE flags in
370 <path>/etc/make.conf</path>, and then to remerge <c>sys-libs/ncurses</c> and
371 also <c>sys-libs/slang</c> if appropriate:
372 </p>
373
374 <pre caption="Emerging ncurses and slang">
375 <comment>(We avoid putting these libraries in our world file with --oneshot)</comment>
376 # <i>emerge --oneshot --verbose --ask sys-libs/ncurses sys-libs/slang</i>
377 </pre>
378
379 <p>
380 We also need to rebuild packages that link to these, now the USE changes have
381 been applied. The tool we use (<c>revdep-rebuild</c>) is part of the
382 <c>gentoolkit</c> package.
383 </p>
384
385 <pre caption="Rebuilding of programs that link to ncurses or slang">
386 # <i>revdep-rebuild --soname libncurses.so.5</i>
387 # <i>revdep-rebuild --soname libslang.so.1</i>
388 </pre>
389
390 </body>
391 </section>
392 <section>
393 <title>KDE, GNOME and Xfce</title>
394 <body>
395
396 <p>
397 All of the major desktop environments have full Unicode support, and will
398 require no further setup than what has already been covered in this guide. This
399 is because the underlying graphical toolkits (Qt or GTK+2) are UTF-8 aware.
400 Subsequently, all applications running on top of these toolkits should be
401 UTF-8-aware out of the box.
402 </p>
403
404 <p>
405 The exceptions to this rule come in Xlib and GTK+1. GTK+1 requires a
406 iso-10646-1 FontSpec in the ~/.gtkrc, for example
407 <c>-misc-fixed-*-*-*-*-*-*-*-*-*-*-iso10646-1</c>. Also, applications using
408 Xlib or Xaw will need to be given a similar FontSpec, otherwise they will not
409 work.
410 </p>
411
412 <note>
413 If you have a version of the gnome1 control center around, use that instead.
414 Pick any iso10646-1 font from there.
415 </note>
416
417 <pre caption="Example ~/.gtkrc (for GTK+1) that defines a Unicode compatible font">
418 style "user-font"
419 {
420 fontset="-misc-fixed-*-*-*-*-*-*-*-*-*-*-iso10646-1"
421 }
422 widget_class "*" style "user-font"
423 </pre>
424
425 <p>
426 If an application has support for both a Qt and GTK+2 GUI, the GTK+2 GUI will
427 generally give better results with Unicode.
428 </p>
429
430 </body>
431 </section>
432 <section>
433 <title>X11 and Fonts</title>
434 <body>
435
436 <impo>
437 <c>x11-base/xorg-x11</c> has far better support for Unicode than XFree86
438 and is <e>highly</e> recommended.
439 </impo>
440
441 <p>
442 TrueType fonts have support for Unicode, and most of the fonts that ship with
443 Xorg have impressive character support, although, obviously, not every single
444 glyph available in Unicode has been created for that font. To build fonts
445 (including the Bitstream Vera set) with support for East Asian letters with X,
446 make sure you have the <c>cjk</c> USE flag set. Many other applications utilise
447 this flag, so it may be worthwhile to add it as a permanent USE flag.
448 </p>
449
450 <p>
451 Also, several font packages in Portage are Unicode aware.
452 </p>
453
454 <pre caption="Optional: Install some more Unicode-aware fonts">
455 # <i>emerge terminus-font intlfonts freefonts cronyx-fonts corefonts</i>
456 </pre>
457
458 </body>
459 </section>
460 <section>
461 <title>Window Managers and Terminal Emulators</title>
462 <body>
463
464 <p>
465 Window managers not built on GTK or Qt generally have very good Unicode
466 support, as they often use the Xft library for handling fonts. If your window
467 manager does not use Xft for fonts, you can still use the FontSpec mentioned in
468 the previous section as a Unicode font.
469 </p>
470
471 <p>
472 Terminal emulators that use Xft and support Unicode are harder to come by.
473 Aside from Konsole and gnome-terminal, the best options in Portage are
474 <c>x11-terms/rxvt-unicode</c>, <c>xfce-extra/terminal</c>,
475 <c>gnustep-apps/terminal</c>, <c>x11-terms/mlterm</c>, <c>x11-terms/mrxvt</c> or
476 plain <c>x11-terms/xterm</c> when built with the <c>unicode</c> USE flag and
477 invoked as <c>uxterm</c>. <c>app-misc/screen</c> supports UTF-8 too, when
478 invoked as <c>screen -u</c> or the following is put into the
479 <path>~/.screenrc</path>:
480 </p>
481
482 <pre caption="~/.screenrc for UTF-8">
483 defutf8 on
484 </pre>
485
486 </body>
487 </section>
488 <section>
489 <title>Vim, Emacs, Xemacs and Nano</title>
490 <body>
491
492 <p>
493 Vim, Emacs and Xemacs provide full UTF-8 support, and also have builtin
494 detection of UTF-8 files. For further information in Vim, use <c>:help
495 mbyte.txt</c>.
496 </p>
497
498 <p>
499 Nano currently does not provide support for UTF-8, although it has been planned
500 for a long time. With luck, this will change in future. At the time of writing,
501 UTF-8 support is in Nano's CVS, and should be included in the next release.
502 </p>
503
504 </body>
505 </section>
506 <section>
507 <title>Shells</title>
508 <body>
509
510 <p>
511 Currently, <c>bash</c> provides full Unicode support through the GNU readline
512 library. Z Shell users are in a somewhat worse position -- no parts of the
513 shell have Unicode support, although there is a concerted effort to add
514 multibyte character set support underway at the moment.
515 </p>
516
517 <p>
518 The C shell, <c>tcsh</c> and <c>ksh</c> do not provide UTF-8 support at all.
519 </p>
520
521 </body>
522 </section>
523 <section>
524 <title>Irssi</title>
525 <body>
526
527 <p>
528 Since 0.8.10, Irssi has complete UTF-8 support, although it does require a user
529 to set an option.
530 </p>
531
532 <pre caption="Enabling UTF-8 in Irssi">
533 /set term_charset UTF-8
534 </pre>
535
536 <p>
537 For channels where non-ASCII characters are often exchanged in non-UTF-8
538 charsets, the <c>/recode</c> command may be used to convert the characters.
539 Type <c>/help recode</c> for more information.
540 </p>
541
542 </body>
543 </section>
544 <section>
545 <title>Mutt</title>
546 <body>
547
548 <p>
549 The Mutt mail user agent has very good Unicode support. To use UTF-8 with Mutt,
550 put the following in your <path>~/.muttrc</path>:
551 </p>
552
553 <pre caption="~/.muttrc for UTF-8">
554 set send_charset="utf8" <comment>(outgoing character set)</comment>
555 set charset="utf8" <comment>(display character set)</comment>
556 </pre>
557
558 <note>
559 You may still see '?' in mail you read with Mutt. This is a result of people
560 using Latin (ISO 8859) or another charset for email transmission. It is best to
561 tell them to use UTF-8 for mail, and point them to the IETF RFC 2277 (see
562 References at the end of this document). Also note that in some lists,
563 subscribers may not like UTF-8. Be sure that the group or person you are
564 communicating with does not mind UTF-8.
565 </note>
566
567 <p>
568 Further information is available from the <uri
569 link="http://wiki.mutt.org/index.cgi?MuttFaq/Charset"> Mutt WikiWiki</uri>.
570 </p>
571
572 </body>
573 </section>
574 <section>
575 <title>Testing it all out</title>
576 <body>
577
578 <p>
579 There are numerous UTF-8 test websites around. <c>net-www/w3m</c>,
580 <c>net-www/links</c>, <c>net-www/elinks</c>, <c>net-www/lynx</c> and all
581 Mozilla based browsers (including Firefox) support UTF-8. Konqueror and Opera
582 have full UTF-8 support too.
583 </p>
584
585 <p>
586 When using one of the text-only web browsers, make absolutely sure you are
587 using a Unicode-aware terminal.
588 </p>
589
590 <p>
591 If you see certain characters displayed as boxes with letters or numbers
592 inside, this means that your font does not have a character for the symbol or
593 glyph that the UTF-8 wants. Instead, it displays a box with the hex code of the
594 UTF-8 symbol.
595 </p>
596
597 <ul>
598 <li>
599 <uri link="http://www.w3.org/2001/06/utf-8-test/UTF-8-demo.html">A W3C
600 UTF-8 Test Page</uri>
601 </li>
602 <li>
603 <uri link="http://titus.uni-frankfurt.de/indexe.htm?/unicode/unitest.htm">
604 A UTF-8 test page provided by the University of Frankfurt</uri>
605 </li>
606 </ul>
607
608 </body>
609 </section>
610 <section>
611 <title>Input Methods</title>
612 <body>
613
614 <p>
615 <e>Dead keys</e> may be used to input characters in X that are not included on
616 your keyboard. These work by pressing your right Alt key (or in some countries,
617 AltGr) and an optional key from the non-alphabetical section of the keyboard to
618 the left of the return key at once, releasing them, and then pressing a letter.
619 The dead key should modify it. Input can be further modified by using the Shift
620 key at the same time as pressing the AltGr and modifier.
621 </p>
622
623 <p>
624 To enable dead keys in X, you need a layout that supports it. Most European
625 layouts already have dead keys with the default variant. However, this is not
626 true of North American layouts. Although there is a degree of inconsistency
627 between layouts, the easiest solution seems to be to use a layout in the form
628 "en_US" rather than "us", for example. The layout is set in
629 <path>/etc/X11/xorg.conf</path> like so:
630 </p>
631
632 <pre caption="/etc/X11/xorg.conf snippet">
633 Section "InputDevice"
634 Identifier "Keyboard0"
635 Driver "kbd"
636 Option "XkbLayout" "en_US" <comment># Rather than just "us"</comment>
637 <comment>(Other Xkb options here)</comment>
638 EndSection
639 </pre>
640
641 <note>
642 The preceding change only needs to be applied if you are using a North American
643 layout, or another layout where dead keys do not seem to be working. European
644 users should have working dead keys as is.
645 </note>
646
647 <p>
648 This change will come into effect when your X server is restarted. To apply the
649 change now, use the <c>setxkbmap</c> tool, for example, <c>setxkbmap en_US</c>.
650 </p>
651
652 <p>
653 It is probably easiest to describe dead keys with examples. Although the
654 results are locale dependent, the concepts should remain the same regardless of
655 locale. The examples contain UTF-8, so to view them you need to either tell
656 your browser to view the page as UTF-8, or have a UTF-8 locale already
657 configured.
658 </p>
659
660 <p>
661 When I press AltGr and [ at once, release them, and then press a, 'ä' is
662 produced. When I press AltGr and [ at once, and then press e, 'ë' is produced.
663 When I press AltGr and ; at once, 'á' is produced, and when I press AltGr and ;
664 at once, release them, and then press e, 'é' is produced.
665 </p>
666
667 <p>
668 By pressing AltGr, Shift and [ at once, releasing them, and then pressing a, a
669 Scandinavian 'å' is produced. Similarly, when I press AltGr, Shift and [ at
670 once, release <e>only</e> the [, and then press it again, '˚' is produced.
671 Although it looks like one, this (U+02DA) is not the same as a degree symbol
672 (U+00B0). This works for other accents produced by dead keys — AltGr and [,
673 releasing only the [, then pressing it again makes '¨'.
674 </p>
675
676 <p>
677 AltGr can be used with alphabetical keys alone. For example, AltGr and m, a
678 Greek lower-case letter mu is produced: 'µ'.
679 </p>
680
681 </body>
682 </section>
683 <section>
684 <title>Resources</title>
685 <body>
686
687 <ul>
688 <li>
689 <uri link="http://www.wikipedia.com/wiki/Unicode">The Wikipedia entry for
690 Unicode</uri>
691 </li>
692 <li>
693 <uri link="http://www.wikipedia.com/wiki/UTF-8">The Wikipedia entry for
694 UTF-8</uri>
695 </li>
696 <li><uri link="http://www.unicode.org">Unicode.org</uri></li>
697 <li><uri link="http://www.utf-8.com">UTF-8.com</uri></li>
698 <li><uri link="http://www.ietf.org/rfc/rfc3629.txt">RFC 3629</uri></li>
699 <li><uri link="http://www.ietf.org/rfc/rfc2277.txt">RFC 2277</uri></li>
700 </ul>
701
702 </body>
703 </section>
704 </chapter>
705 </guide>

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