11.3. awk localization

Provide a default value for the internationalisation variables that are unset or null. If LANG is unset or null, the corresponding value from the implementation-dependent default locale will be used. If any of the internationalisation variables contains an invalid setting, the utility will behave as if none of the variables had been defined.

If set to a non-empty string value, override the values of all the other internationalisation variables.

Determine the locale for the behaviour of ranges, equivalence classes and multi-character collating elements within regular expressions and in comparisons of string values.

Determine the locale for the interpretation of sequences of bytes of text data as characters (for example, single- versus multi-byte characters in arguments and input files), the behaviour of character classes within regular expressions, the identification of characters as letters, and the mapping of upper- and lower-case characters for the toupper and tolower functions.

Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error.

Determine the radix character used when interpreting numeric input, performing conversions between numeric and string values and formatting numeric output. Regardless of locale, the period character (the decimal-point character of the POSIX locale) is the decimal-point character recognised in processing awk programs (including assignments in command-line arguments).

Determine the location of message catalogues for the processing of LC_MESSAGES .

Determine the search path when looking for commands executed by system(expr), or input and output pipes. See the XBD specification, Environment Variables.