Get or set the current locale, used for various internationalizations. Locales are strings, such as `sv_SE'.

If locale is given then the locale for the given category is set and the new value returned. If locale is not given then the current value is returned. category should be one of the following values

— Variable: LC_ALL
— Variable: LC_COLLATE
— Variable: LC_CTYPE
— Variable: LC_MESSAGES
— Variable: LC_MONETARY
— Variable: LC_NUMERIC
— Variable: LC_TIME

A common usage is `(setlocale LC_ALL "")', which initializes all categories based on standard environment variables (LANG etc). For full details on categories and locale names see Locales and Internationalization.