"Fossies" - the Fresh Open Source Software Archive

Member "xterm-379/README.i18n" (13 Nov 2003, 8012 Bytes) of package /linux/misc/xterm-379.tgz:

As a special service "Fossies" has tried to format the requested text file into HTML format (style: standard) with prefixed line numbers. Alternatively you can here view or download the uninterpreted source code file.

    1 -- $XFree86: xc/programs/xterm/README.i18n,v 1.1 2003/11/13 01:16:37 dickey Exp $
    3 Using xterm in your language
    4 ============================
    6 Since XFree86 version 4.0, the internationalization (i18n) feature of
    7 xterm is gradually improved.  Xterm is being improved even now.  You
    8 need only set the standard locale environment variables such as
    9 LC_CTYPE, LC_ALL, LC_CTYPE, or LANG.  Once the locale is set up you can
   10 use xterm in your favorite character encoding.
   12 This document explains how the i18n feature is realized and how to
   13 configure xterm for your character encoding.
   15 Refer to locale(7) for details of the locale mechanism.
   18 Basic i18n-related settings and resources
   19 =========================================
   21 These settings apply to XFree86 xterm patch #181, and the program luit
   22 which is distributed with XFree86 4.4
   24 1.  Usage of "locale mode"
   26     On startup, xterm must be in "locale mode" to make it follow the
   27     current locale.  You can invoke xterm in locale mode in these ways:
   29     a.  Set "vt100.locale" resource "true".  This resource was
   30         introduced since XFree86 4.3.  The default value of the "locale"
   31         resource is "medium", which means xterm follows the locale only
   32         in Chinese, Japanese, Korean, or Thai locales.  For example,
   34           XTerm*locale: true
   36         in your ~/.Xresources file.
   38     or
   40     b.  Invoke xterm with the "-lc" option.
   42 2.  Converter program "luit"
   44     The "luit" must be available in the standard XFree86 binary
   45     directory.  It is usually available because it is part of the
   46     XFree86 distribution.  The standard binary directory may differ from
   47     system to system.  /usr/X11R6/bin/luit is an example.
   49     "luit" is used to convert between Unicode and the character encoding
   50     for your locale.  When built for XFree86, xterm includes logic for
   51     invoking luit.
   53 3.  Locale setting
   55     Finally, you will need to configure your locale.  We expect that you
   56     have already configured your locale for other software.  For example,
   58       LANG=de_DE@euro
   59       export LANG
   61     in your ~/.xsession file.  There are many ways to configure locale. 
   62     For example, your display manager may have a mechanism to invoke a
   63     window manager in your favorite locale, or you may have system-wide
   64     locale setting in /etc/environment.  You may also have set the
   65     LC_ALL variable instead of the LANG variable.
   68 How to use xterm in different locale temporarily
   69 ================================================
   71 You may sometimes need to invoke xterm in a different character encoding
   72 than your current locale.  For example, use xterm to login remote systems
   73 in different locale.
   75 Do this by invoking xterm in the target locale.  For example,
   77   $ LANG=ru_RU.KOI8-R xterm &
   79 Previously, font setting has been used in such cases.
   81   $ xterm -fn -misc-fixed-medium-r-normal--10-*-*-*-*-*-koi8-r &
   83 This does not work well in conjunction with the "locale" resource,
   84 because luit and xterm combined rely upon Unicode fonts.
   87 How to set fonts for UTF-8/locale modes
   88 =======================================
   90 Since xterm patch #181, xterm can automatically use Unicode fonts in
   91 UTF-8 mode and locale mode.  Few of you will need to modify the default
   92 setting to display your language.  In particular, Unicode fonts in
   93 combination with locale mode will satisfy the needs of not only
   94 ISO-8859-1 users but also East Asian and other non-ISO-8859-1 users.
   96 If you want to set your favorite Unicode font for UTF-8 and locale
   97 modes, you should add a line such as the following in your ~/.Xresources
   98 file:
  100     XTerm*VT100.utf8Fonts.font: \
  101          -misc-fixed-medium-r-semicondensed--13-120-75-75-c-60-iso10646-1
  103 The leading "XTerm*" pattern is more specific than the system's
  104 app-defaults file, therefore it overrides the corresponding line
  105 beginning with
  107     *VT100.utf8Fonts.font:
  109 Here is an additional note.  If you want to display East Asian
  110 doublewidth characters (CJK Ideogram, Hiragana, Katakana, Hangul,
  111 and so on), we recommend using
  113     -misc-fixed-medium-r-semicondensed--13-*-*-*-*-*-iso10646-1
  115 or
  117     -misc-fixed-medium-r-normal--18-*-*-*-*-*-iso10646-1
  119 because these two fonts have corresponding doublewidth fonts.  These
  120 fonts are used as default font and default "Large" font, respectively.
  123 The internals of xterm i18n
  124 ===========================
  126 You do not need to read this section if you only want to configure your
  127 xterm.  Here we describe how xterm is implemented to support i18n.
  129 The original version of xterm does not support locale or character
  130 encoding.  Its I/O stream is interpreted as a mere 8-bit index for a
  131 font.
  133 Beginning with XFree86 4.0, xterm supported UTF-8.  It was implemented
  134 as a separate UTF-8 mode from the conventional 8-bit mode.  Character
  135 encodings had no effect on the 8-bit mode.  The UTF-8 mode has been
  136 extended to support doublewidth characters (for East Asian characters)
  137 and combining characters (such as accents for Latin alphabets and Thai
  138 vowels/tone marks).
  140 Doublewidth characters are characters that occupy two continuing
  141 columns on the terminal.  Xterm uses separate fonts for normal
  142 (singlewidth) characters and doublewidth characters.  Though xterm has
  143 configuration items for specifying doublewidth fonts, it will
  144 automatically search for a font with exactly twice as wide and the same
  145 name as the specified normal font.
  147 The default behavior of xterm was modified to use this UTF-8 mode in
  148 UTF-8 locales.  A command line option of "-u8" and a resource of "utf8"
  149 were introduced to choose UTF-8 mode.
  151 "luit" was introduced to XFree86 at version 4.2.  It converts between
  152 UTF-8 and other encodings.  When luit is invoked in a UTF-8 terminal,
  153 the terminal acts as if it is really running in the other encoding.
  155 Since XFree86 version 4.3, xterm provides a new mode to invoke luit
  156 automatically to support various encodings.  The mode where xterm
  157 invokes luit is called "locale mode".  It is the third mode following
  158 conventional 8-bit mode and UTF-8 mode.  In the locale mode, xterm is
  159 aware of the current locale and character encoding.  Since locale mode
  160 uses luit, it is based on the UTF-8 mode.  That is, xterm works in UTF-8
  161 mode and luit works as a converter between UTF-8 and the character
  162 encoding for your locale.  This is why the locale mode always needs
  163 Unicode fonts.  The default behavior of xterm is modified so that the
  164 "locale mode" will be adopted in Chinese (Big5 and GB2312), Japanese
  165 (EUC-JP), Korean (EUC-KR), and Thai (ISO-8859-11, as known as TIS-620)
  166 locales.  Locale mode is chosen for these character encodings because
  167 these encodings are not supported by conventional 8-bit mode even by
  168 changing fonts (ISO-8859-11 needs combining characters and others need
  169 doublewidth characters).
  171 To control the locale mode, command line options of "-lc" and "-en" and
  172 a resource of "locale" were introduced.  The command line option of
  173 "-u8" and a resource of "utf8" were made obsolete by them, though
  174 retained for compatibility.
  176 Since XFree86 version 4.4, xterm can have two sets of default fonts,
  177 one for conventional 8-bit mode and another for UTF-8 and locale modes,
  178 by introducing the "utf8Fonts" subresource.
  181 Future TODO Items
  182 =================
  184 We anticipate that xterm's locale mode will be used increasingly in the
  185 future.  Since the UTF-8 and locale modes use more resources than
  186 conventional 8-bit mode (because it needs larger fonts and another
  187 process "luit"), faster hardware may be needed to gain complete
  188 acceptance by users.  However, the locale mechanism allows users
  189 to manipulate data in a standard form.  Its usefulness compensates
  190 in part for reduced performance.
  192 Xterm supports antialiased fonts ("-fa" and "-fs" command line options). 
  193 Currently UTF-8 nor locale modes do not work with antialiased fonts.
  195 Xterm does not support bi-directional or RTL languages such as Hebrew
  196 and Arab.  A simple standard how terminal should behave for these
  197 languages is needed.
  199 Xterm does not support Unicode characters above U+10000.