locale (1p) - Linux Man Pages
locale: get locale-specific information
PROLOGThis manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.
locale - get locale-specific information
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:
- Specifying a keyword name shall select the named keyword and the category containing that keyword.
- Specifying a category name shall select the named category and all keywords in that category.
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:
- Write information about all available public locales. The available locales shall include POSIX, representing the POSIX locale. The manner in which the implementation determines what other locales are available is implementation-defined.
- Write the names of selected locale categories; see the STDOUT section. The -c option increases 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.
- Write the names and values of selected keywords. The implementation may omit values for some keywords; see the OPERANDS section.
Write names of available charmaps; see the Base Definitions volume
of IEEE Std 1003.1-2001, Section 6.1, Portable Character Set.
The following operand shall be supported:
The name of a locale category as defined in the Base Definitions volume
of IEEE Std 1003.1-2001, Chapter 7, Locale, the name of a keyword
in a locale category, or the reserved name
charmap. The named category or keyword shall be selected for
output. If a single name represents both a locale
category name and a keyword name in the current locale, the results
are unspecified. Otherwise, both category and keyword names can
be specified as name operands, in any sequence. It is implementation-defined
whether any keyword values are written for the
categories LC_CTYPE and LC_COLLATE.
The following environment variables shall affect the execution of locale:
- Provide a default value for the internationalization variables that are unset or null. (See the Base Definitions volume of IEEE Std 1003.1-2001, Section 8.2, Internationalization Variables for the precedence of internationalization variables used to determine the values of locale categories.)
- If set to a non-empty string value, override the values of all the other internationalization variables.
- Determine the locale for the interpretation of sequences of bytes of text data as characters (for example, single-byte as opposed to multi-byte characters in arguments and input files).
- Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error.
Determine the location of message catalogs for the processing of LC_MESSAGES
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:
If any arguments are specified:
If the -a option is specified, the names of all the public locales
shall be written, each in the following format:
"%s\n", <locale name>
If the -c option is specified, the names of all selected categories
shall be written, each in the following format:
"%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.
If the -k option is specified, the names and values of selected
keywords shall be written. If a value is non-numeric, it
shall be written in the following format:
"%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.
If the -k option is not specified, selected keyword values shall
be written, each in the following format:
"%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.
If the -m option is specified, then a list of all available
charmaps shall be written, each in the format:
where <charmap> is in a format suitable for use as the option-argument to the localedef -f option.
The following exit values shall be returned:
- All the requested information was found and output successfully.
- An error occurred.
CONSEQUENCES OF ERRORS
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:
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.
LC_ALL=POSIX locale -ck 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.
COPYRIGHTPortions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .