locale [-a| -m]
The locale utility shall write information about the current locale environment, or all public locales, to the standard output. For the purposes of this section, a public locale is one provided by the implementation that is accessible to the application.
When locale is invoked without any arguments, it shall summarize the current locale environment for each locale category as determined by the settings of the environment variables defined in the Base Definitions volume of IEEE Std 1003.1-2001, Chapter 7, Locale.
When invoked with operands, it shall write values that have been assigned to the keywords in the locale categories, as follows:
The locale utility shall conform to the Base Definitions volume of IEEE Std 1003.1-2001, Section 12.2, Utility Syntax Guidelines.
The following options shall be supported:
The following operand shall be supported:
The following environment variables shall affect the execution of locale:
The application shall ensure that the LANG , LC_* , and NLSPATH environment variables specify the current locale environment to be written out; they shall be used if the -a option is not specified.
If locale is invoked without any options or operands, the names and values of the LANG and LC_* environment variables described in this volume of IEEE Std 1003.1-2001 shall be written to the standard output, one variable per line, with LANG first, and each line using the following format. Only those variables set in the environment and not overridden by LC_ALL shall be written using this format:
"%s=%s\n", <variable_name>, <value>
The names of those LC_* variables associated with locale categories defined in this volume of IEEE Std 1003.1-2001 that are not set in the environment or are overridden by LC_ALL shall be written in the following format:
"%s=\"%s\"\n", <variable_name>, <implied value>
The <implied value> shall be the name of the locale that has been selected for that category by the implementation, based on the values in LANG and LC_ALL , as described in the Base Definitions volume of IEEE Std 1003.1-2001, Chapter 8, Environment Variables.
The <value> and <implied value> shown above shall be properly quoted for possible later reentry to the shell. The <value> shall not be quoted using double-quotes (so that it can be distinguished by the user from the <implied value> case, which always requires double-quotes).
The LC_ALL variable shall be written last, using the first format shown above. If it is not set, it shall be written as:
"LC_ALL=\n"
If any arguments are specified:
"%s\n", <locale name>
"%s\n", <category name>
If keywords are also selected for writing (see following items), the category name output shall precede the keyword output for that category.
If the -c option is not specified, the names of the categories shall not be written; only the keywords, as selected by the <name> operand, shall be written.
"%s=\"%s\"\n", <keyword name>, <keyword value>
If the keyword was charmap, the name of the charmap (if any) that was specified via the localedef -f option when the locale was created shall be written, with the word charmap as <keyword name>.
If a value is numeric, it shall be written in one of the following formats:
"%s=%d\n", <keyword name>, <keyword value> "%s=%c%o\n", <keyword name>, <escape character>, <keyword value> "%s=%cx%x\n", <keyword name>, <escape character>, <keyword value>
where the <escape character> is that identified by the escape_char keyword in the current locale; see the Base Definitions volume of IEEE Std 1003.1-2001, Section 7.3, Locale Definition.
Compound keyword values (list entries) shall be separated in the output by semicolons. When included in keyword values, the semicolon, the double-quote, the backslash, and any control character shall be preceded (escaped) with the escape character.
"%s\n", <keyword value>
If the keyword was charmap, the name of the charmap (if any) that was specified via the localedef -f option when the locale was created shall be written.
"%s\n", <charmap>
where <charmap> is in a format suitable for use as the option-argument to the localedef -f option.
The standard error shall be used only for diagnostic messages.
The following exit values shall be returned:
Default.
The following sections are informative.
If the LANG environment variable is not set or set to an empty value, or one of the LC_* environment variables is set to an unrecognized value, the actual locales assumed (if any) are implementation-defined as described in the Base Definitions volume of IEEE Std 1003.1-2001, Chapter 8, Environment Variables.
Implementations are not required to write out the actual values for keywords in the categories LC_CTYPE and LC_COLLATE ; however, they must write out the categories (allowing an application to determine, for example, which character classes are available).
In the following examples, the assumption is that locale environment variables are set as follows:
LANG=locale_x LC_COLLATE=locale_y
The command locale would result in the following output:
LANG=locale_x LC_CTYPE="locale_x" LC_COLLATE=locale_y LC_TIME="locale_x" LC_NUMERIC="locale_x" LC_MONETARY="locale_x" LC_MESSAGES="locale_x" LC_ALL=
The order of presentation of the categories is not specified by this volume of IEEE Std 1003.1-2001.
The command:
LC_ALL=POSIX locale -ck decimal_point
would produce:
LC_NUMERIC decimal_point="."
The following command shows an application of locale to determine whether a user-supplied response is affirmative:
if printf "%s\n" "$response" | grep -Eq "$(locale yesexpr)"
then
affirmative processing goes here
else
non-affirmative processing goes here
fi
The output for categories LC_CTYPE and LC_COLLATE has been made implementation-defined because there is a questionable value in having a shell script receive an entire array of characters. It is also difficult to return a logical collation description, short of returning a complete localedef source.
The -m option was included to allow applications to query for the existence of charmaps. The output is a list of the charmaps (implementation-supplied and user-supplied, if any) on the system.
The -c option was included for readability when more than one category is selected (for example, via more than one keyword name or via a category name). It is valid both with and without the -k option.
The charmap keyword, which returns the name of the charmap (if any) that was used when the current locale was created, was included to allow applications needing the information to retrieve it.
localedef , the Base Definitions volume of IEEE Std 1003.1-2001, Section 7.3, Locale Definition