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  1. <?xml version="1.0" encoding="ISO-8859-1"?>
  2. <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
  3. "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
  4. <!ENTITY % general-entities SYSTEM "../general.ent">
  5. %general-entities;
  6. ]>
  7. <sect1 id="ch-scripts-profile">
  8. <?dbhtml filename="profile.html"?>
  9. <title>The Bash Shell Startup Files</title>
  10. <indexterm zone="ch-scripts-profile">
  11. <primary sortas="e-/etc/profile">/etc/profile</primary>
  12. </indexterm>
  13. <para>The shell program <command>/bin/bash</command> (hereafter referred to
  14. as <quote>the shell</quote>) uses a collection of startup files to help
  15. create an environment to run in. Each file has a specific use and may affect
  16. login and interactive environments differently. The files in the <filename
  17. class="directory">/etc</filename> directory provide global settings. If an
  18. equivalent file exists in the home directory, it may override the global
  19. settings.</para>
  20. <para>An interactive login shell is started after a successful login, using
  21. <command>/bin/login</command>, by reading the <filename>/etc/passwd</filename>
  22. file. An interactive non-login shell is started at the command-line (e.g.,
  23. <prompt>[prompt]$</prompt><command>/bin/bash</command>). A non-interactive
  24. shell is usually present when a shell script is running. It is non-interactive
  25. because it is processing a script and not waiting for user input between
  26. commands.</para>
  27. <para>For more information, see <command>info bash</command> under the
  28. <emphasis>Bash Startup Files and Interactive Shells</emphasis> section.</para>
  29. <para>The files <filename>/etc/profile</filename> and
  30. <filename>~/.bash_profile</filename> are read when the shell is
  31. invoked as an interactive login shell.</para>
  32. <para>The base <filename>/etc/profile</filename> below sets some
  33. environment variables necessary for native language support. Setting
  34. them properly results in:</para>
  35. <itemizedlist>
  36. <listitem>
  37. <para>The output of programs translated into the native language</para>
  38. </listitem>
  39. <listitem>
  40. <para>Correct classification of characters into letters, digits and other
  41. classes. This is necessary for <command>bash</command> to properly accept
  42. non-ASCII characters in command lines in non-English locales</para>
  43. </listitem>
  44. <listitem>
  45. <para>The correct alphabetical sorting order for the country</para>
  46. </listitem>
  47. <listitem>
  48. <para>Appropriate default paper size</para>
  49. </listitem>
  50. <listitem>
  51. <para>Correct formatting of monetary, time, and date values</para>
  52. </listitem>
  53. </itemizedlist>
  54. <para>Replace <replaceable>&lt;ll&gt;</replaceable> below with the two-letter code
  55. for the desired language (e.g., <quote>en</quote>) and
  56. <replaceable>&lt;CC&gt;</replaceable> with the two-letter code for the appropriate
  57. country (e.g., <quote>GB</quote>). <replaceable>&lt;charmap&gt;</replaceable> should
  58. be replaced with the canonical charmap for your chosen locale. Optional
  59. modifiers such as <quote>@euro</quote> may also be present.</para>
  60. <para>The list of all locales supported by Glibc can be obtained by running
  61. the following command:</para>
  62. <screen role="nodump"><userinput>locale -a</userinput></screen>
  63. <para>Charmaps can have a number of aliases, e.g., <quote>ISO-8859-1</quote>
  64. is also referred to as <quote>iso8859-1</quote> and <quote>iso88591</quote>.
  65. Some applications cannot handle the various synonyms correctly (e.g., require
  66. that <quote>UTF-8</quote> is written as <quote>UTF-8</quote>, not
  67. <quote>utf8</quote>), so it is safest in most
  68. cases to choose the canonical name for a particular locale. To determine
  69. the canonical name, run the following command, where <replaceable>&lt;locale
  70. name&gt;</replaceable> is the output given by <command>locale -a</command> for
  71. your preferred locale (<quote>en_GB.iso88591</quote> in our example).</para>
  72. <screen role="nodump"><userinput>LC_ALL=<replaceable>&lt;locale name&gt;</replaceable> locale charmap</userinput></screen>
  73. <para>For the <quote>en_GB.iso88591</quote> locale, the above command
  74. will print:</para>
  75. <screen><computeroutput>ISO-8859-1</computeroutput></screen>
  76. <para>This results in a final locale setting of <quote>en_GB.ISO-8859-1</quote>.
  77. It is important that the locale found using the heuristic above is tested prior
  78. to it being added to the Bash startup files:</para>
  79. <screen role="nodump"><userinput>LC_ALL=&lt;locale name&gt; locale language
  80. LC_ALL=&lt;locale name&gt; locale charmap
  81. LC_ALL=&lt;locale name&gt; locale int_curr_symbol
  82. LC_ALL=&lt;locale name&gt; locale int_prefix</userinput></screen>
  83. <para>The above commands should print the language name, the character
  84. encoding used by the locale, the local currency, and the prefix to dial
  85. before the telephone number in order to get into the country. If any of the
  86. commands above fail with a message similar to the one shown below, this means
  87. that your locale was either not installed in Chapter 6 or is not supported by
  88. the default installation of Glibc.</para>
  89. <screen><computeroutput>locale: Cannot set LC_* to default locale: No such file or directory</computeroutput></screen>
  90. <para>If this happens, you should either install the desired locale using the
  91. <command>localedef</command> command, or consider choosing a different locale.
  92. Further instructions assume that there are no such error messages from
  93. Glibc.</para>
  94. <!-- FIXME: the xlib example will became obsolete real soon -->
  95. <para>Some packages beyond LFS may also lack support for your chosen locale. One
  96. example is the X library (part of the X Window System), which outputs the
  97. following error message if the locale does not exactly match one of the character
  98. map names in its internal files:</para>
  99. <screen><computeroutput>Warning: locale not supported by Xlib, locale set to C</computeroutput></screen>
  100. <para>In several cases Xlib expects that the character map will be listed in
  101. uppercase notation with canonical dashes. For instance, "ISO-8859-1" rather
  102. than "iso88591". It is also possible to find an appropriate specification by
  103. removing the charmap part of the locale specification. This can be checked
  104. by running the <command>locale charmap</command> command in both locales.
  105. For example, one would have to change "de_DE.ISO-8859-15@euro" to
  106. "de_DE@euro" in order to get this locale recognized by Xlib.</para>
  107. <para>Other packages can also function incorrectly (but may not necessarily
  108. display any error messages) if the locale name does not meet their expectations.
  109. In those cases, investigating how other Linux distributions support your locale
  110. might provide some useful information.</para>
  111. <para>Once the proper locale settings have been determined, create the
  112. <filename>/etc/profile</filename> file:</para>
  113. <screen><userinput>cat &gt; /etc/profile &lt;&lt; "EOF"
  114. <literal># Begin /etc/profile
  115. export LANG=<replaceable>&lt;ll&gt;_&lt;CC&gt;.&lt;charmap&gt;&lt;@modifiers&gt;</replaceable>
  116. # End /etc/profile</literal>
  117. EOF</userinput></screen>
  118. <para>The <quote>C</quote> (default) and <quote>en_US</quote> (the recommended
  119. one for United States English users) locales are different. <quote>C</quote>
  120. uses the US-ASCII 7-bit character set, and treats bytes with the high bit set
  121. as invalid characters. That's why, e.g., the <command>ls</command> command
  122. substitutes them with question marks in that locale. Also, an attempt to send
  123. mail with such characters from Mutt or Pine results in non-RFC-conforming
  124. messages being sent (the charset in the outgoing mail is indicated as <quote>unknown
  125. 8-bit</quote>). So you can use the <quote>C</quote> locale only if you are sure that
  126. you will never need 8-bit characters.</para>
  127. <para>UTF-8 based locales are not supported well by many programs. E.g., the
  128. <command>watch</command> program displays only ASCII characters in UTF-8
  129. locales and has no such restriction in traditional 8-bit locales like en_US.
  130. Work is in progress to document and, if possible, fix such problems, see
  131. <ulink url="&blfs-root;view/svn/introduction/locale-issues.html"/>.</para>
  132. </sect1>