SETLOCALE(3)             BSD Library Functions Manual             SETLOCALE(3)

NAME
     setlocale -- natural language formatting for C

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <locale.h>

     char *
     setlocale(int category, const char *locale);

DESCRIPTION
     The setlocale() function sets the C library's notion of natural language
     formatting style for particular sets of routines.  Each such style is
     called a `locale' and is invoked using an appropriate name passed as a C
     string.

     The setlocale() function recognizes several categories of routines.
     These are the categories and the sets of routines they select:

     LC_ALL       Set the entire locale generically.

     LC_COLLATE   Set a locale for string collation routines.  This controls
                  alphabetic ordering in strcoll() and strxfrm().

     LC_CTYPE     Set a locale for the ctype(3) and multibyte(3) functions.
                  This controls recognition of upper and lower case, alpha-
                  betic or non-alphabetic characters, and so on.

     LC_MESSAGES  Set a locale for message catalogs, see catopen(3) function.

     LC_MONETARY  Set a locale for formatting monetary values; this affects
                  the localeconv() function.

     LC_NUMERIC   Set a locale for formatting numbers.  This controls the for-
                  matting of decimal points in input and output of floating
                  point numbers in functions such as printf() and scanf(), as
                  well as values returned by localeconv().

     LC_TIME      Set a locale for formatting dates and times using the
                  strftime() function.

     Only three locales are defined by default: the empty string "" (which
     denotes the native environment) and the "C" and "POSIX" locales (which
     denote the C language environment).  A locale argument of NULL causes
     setlocale() to return the current locale.  An argument of "" will deter-
     mine the name of the new locale taking into account the environment vari-
     ables LANG and LC_*.  If these environment variables yield a locale that
     is invalid, NULL will be returned and the current locale will remain
     unchanged.  By default, C programs start in the "C" locale.  The only
     function in the library that sets the locale is setlocale(); the locale
     is never changed as a side effect of some other routine.

RETURN VALUES
     Upon successful completion, setlocale() returns the string associated
     with the specified category for the requested locale.  The setlocale()
     function returns NULL and fails to change the locale if the given combi-
     nation of category and locale makes no sense.

FILES
     $PATH_LOCALE/locale/category
     /usr/share/locale/locale/category  locale file for the locale locale and
                                        the category category.
     /usr/local/share/locale/locale/category
                                        locale file for the locale locale and
                                        the category category.

ERRORS
     No errors are defined.

SEE ALSO
     colldef(1), mklocale(1), catopen(3), ctype(3), localeconv(3),
     multibyte(3), strcoll(3), strxfrm(3), euc(5), utf8(5), environ(7)

STANDARDS
     The setlocale() function conforms to ISO/IEC 9899:1999 (``ISO C99'').

HISTORY
     The setlocale() function first appeared in 4.4BSD.

BSD                            November 21, 2003                           BSD