C in a Nutshell

Name

setlocale

Synopsis

Gets or sets locale information

#include <locale.h>
char *setlocale( int category, const char *locale_name );

The setlocale() function allows you to adapt the program to the local conditions of a given regional and cultural environment—called a locale—such as clocks and calendars, decimal point and currency symbol characters, and other conventions. The setlocale() function returns a pointer to a string that identifies the new locale, or the current locale if you pass the function a null pointer as its second argument.

The locale conventions are classed in categories. You can set the individual categories of the program’s locale individually. The header file locale.h defines the following macros to identify each category in the first argument to setlocale():

LC_ALL

Includes all the other categories.

LC_COLLATE

Affects the functions strcoll(), strxfrm(), wcscoll(), and wcsxfrm().

LC_CTYPE

Affects the character-handling functions (such as isalpha(), tolower(), and so on), and the multibyte and wide-character functions.

LC_MONETARY

Affects the monetary format information provided by the localeconv() function.

LC_NUMERIC

Affects the nonmonetary numeral format information provided by the localeconv() function, and the decimal point used by the printf() and scanf() functions, and by string conversion functions such as strtod().

LC_TIME

Affects the time and date string format produced by the strftime() and wcsftime() functions.

The second argument to setlocale(), locale_name, is a ...