locale - description of multilanguage support

A locale is a set of language and cultural rules. These cover aspects such as language for messages, different character sets, lexicographic conventions, and so on. A program needs to be able to determine its locale and act accordingly to be portable to different cultures.

The header <locale.h> declares data types, functions, and macros which are useful in this task.

The functions it declares are setlocale(3) to set the current locale, and localeconv(3) to get information about number formatting.

There are different categories for locale information a program might need; they are declared as macros. Using them as the first argument to the setlocale(3) function, it is possible to set one of these to the desired locale:

• LC_ADDRESS
• LC_COLLATE
• LC_CTYPE
• LC_IDENTIFICATION
• LC_MONETARY
• LC_MESSAGES
• LC_MEASUREMENT
• LC_NAME
• LC_NUMERIC
• LC_PAPER
• LC_TELEPHONE
• LC_TIME
• LC_ALL

Source: man 7 locale

Program

locale - get locale-specific information

The locale command displays information about the current locale, or all locales, on standard output.

Example

$ locale
LANG=en_US.UTF-8
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC="en_US.UTF-8"
LC_TIME="en_US.UTF-8"
LC_COLLATE="en_US.UTF-8"
LC_MONETARY="en_US.UTF-8"
LC_MESSAGES="en_US.UTF-8"
LC_PAPER="en_US.UTF-8"
LC_NAME="en_US.UTF-8"
LC_ADDRESS="en_US.UTF-8"
LC_TELEPHONE="en_US.UTF-8"
LC_MEASUREMENT="en_US.UTF-8"
LC_IDENTIFICATION="en_US.UTF-8"
LC_ALL=

$ locale date_fmt
%a %b %e %H:%M:%S %Z %Y

$ locale -k date_fmt
date_fmt="%a %b %e %H:%M:%S %Z %Y"

$ locale -ck date_fmt
LC_TIME
date_fmt="%a %b %e %H:%M:%S %Z %Y"

$ locale LC_TELEPHONE
+%c (%a) %l
(%a) %l
11
1
UTF-8

$ locale -k LC_TELEPHONE
tel_int_fmt="+%c (%a) %l"
tel_dom_fmt="(%a) %l"
int_select="11"
int_prefix="1"
telephone-codeset="UTF-8"

The  following  example compiles a custom locale from the ./wrk directory with the localedef(1) utility under the $HOME/.locale directory, then tests the result with the date(1) command, and then sets
the environment variables LOCPATH and LANG in the shell profile file so that the custom locale will be used in the subsequent user sessions:

$ mkdir -p $HOME/.locale
$ I18NPATH=./wrk/ localedef -f UTF-8 -i fi_SE $HOME/.locale/fi_SE.UTF-8
$ LOCPATH=$HOME/.locale LC_ALL=fi_SE.UTF-8 date
$ echo "export LOCPATH=\$HOME/.locale" >> $HOME/.bashrc
$ echo "export LANG=fi_SE.UTF-8" >> $HOME/.bashrc