7.9. The Bash Shell Startup Files

The shell program /bin/bash (hereafter referred to as “the shell”) uses a collection of startup files to help create an environment to run in. Each file has a specific use and may affect login and interactive environments differently. The files in the /etc directory provide global settings. If an equivalent file exists in the home directory, it may override the global settings.

An interactive login shell is started after a successful login, using /bin/login, by reading the /etc/passwd file. An interactive non-login shell is started at the command-line (e.g., [prompt]$/bin/bash). A non-interactive shell is usually present when a shell script is running. It is non-interactive because it is processing a script and not waiting for user input between commands.

For more information, see info bash under the Bash Startup Files and Interactive Shells section.

The files /etc/profile and ~/.bash_profile are read when the shell is invoked as an interactive login shell.

The base /etc/profile below sets some environment variables necessary for native language support. Setting them properly results in:

This script also sets the INPUTRC environment variable that makes Bash and Readline use the /etc/inputrc file created earlier.

Replace [ll] below with the two-letter code for the desired language (e.g., “en”) and [CC] with the two-letter code for the appropriate country (e.g., “GB”). [charmap] should be replaced with the canonical charmap for your chosen locale.

The list of all locales supported by Glibc can be obtained by running the following command:

locale -a

Locales can have a number of synonyms, e.g. “ISO-8859-1” is also referred to as “iso8859-1” and “iso88591”. Some applications cannot handle the various synonyms correctly, so it is safest to choose the canonical name for a particular locale. To determine the canonical name, run the following command, where [locale name] is the output given by locale -a for your preferred locale (“en_GB.iso88591” in our example).

LC_ALL=[locale name] locale charmap

For the “en_GB.iso88591” locale, the above command will print:

ISO-8859-1

This results in a final locale setting of “en_GB.ISO-8859-1”.

Once the proper locale settings have been determined, create the /etc/profile file:

cat > /etc/profile << "EOF"
# Begin /etc/profile

export LANG=[ll]_[CC].[charmap]
export INPUTRC=/etc/inputrc

# End /etc/profile
EOF
[Note]

Note

The “C” (default) and “en_US” (the recommended one for United States English users) locales are different.

Setting the keyboard layout, screen font, and locale-related environment variables are the only internationalization steps needed to support locales that use ordinary single-byte encodings and left-to-right writing direction. More complex cases (including UTF-8 based locales) require additional steps and additional patches because many applications tend to not work properly under such conditions. These steps and patches are not included in the LFS book and such locales are not yet supported by LFS.