SETLOCALE(3)              OpenBSD Programmer's Manual             SETLOCALE(3)

NAME
     setlocale, localeconv - natural language formatting for C



SYNOPSIS
     #include <locale.h>

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

     struct lconv *
     localeconv(void);

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 localeconv() routine returns the current locale's parame-
     ters for formatting numbers.

     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) functions.  This controls
                  recognition of upper and lower case, alphabetic or non-al-
                  phabetic characters, and so on.  The real work is done by
                  the setrunelocale() 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 de-
     notes the native environment, and the "C" and "POSIX" locales, which de-
     note the C language environment.  A locale argument of NULL causes
     setlocale() to return the current locale.  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 oth-
     er routine.

     The localeconv() function returns a pointer to a structure which provides
     parameters for formatting numbers, especially currency values:

           struct lconv {
                   char    *decimal_point;
                   char    *thousands_sep;
                   char    *grouping;
                   char    *int_curr_symbol;
                   char    *currency_symbol;
                   char    *mon_decimal_point;
                   char    *mon_thousands_sep;
                   char    *mon_grouping;
                   char    *positive_sign;
                   char    *negative_sign;
                   char    int_frac_digits;
                   char    frac_digits;
                   char    p_cs_precedes;
                   char    p_sep_by_space;
                   char    n_cs_precedes;
                   char    n_sep_by_space;
                   char    p_sign_posn;
                   char    n_sign_posn;
           };

     The individual fields have the following meanings:

     decimal_point      The decimal point character, except for currency val-
                        ues.

     thousands_sep      The separator between groups of digits before the dec-
                        imal point, except for currency values.

     grouping           The sizes of the groups of digits, except for currency
                        values.  This is a pointer to a vector of integers,
                        each of size char, representing group size from low
                        order digit groups to high order (right to left).  The
                        list may be terminated with 0 or CHAR_MAX. If the list
                        is terminated with 0, the last group size before the 0
                        is repeated to account for all the digits.  If the
                        list is terminated with CHAR_MAX, no more grouping is
                        performed.

     int_curr_symbol    The standardized international currency symbol.

     currency_symbol    The local currency symbol.

     mon_decimal_point  The decimal point character for currency values.

     mon_thousands_sep  The separator for digit groups in currency values.

     mon_grouping       Like grouping but for currency values.

     positive_sign      The character used to denote non-negative currency
                        values, usually the empty string.

     negative_sign      The character used to denote negative currency values,
                        usually a minus sign.

     int_frac_digits    The number of digits after the decimal point in an in-
                        ternational-style currency value.

     frac_digits        The number of digits after the decimal point in the
                        local style for currency values.

     p_cs_precedes      1 if the currency symbol precedes the currency value
                        for non-negative values, 0 if it follows.

     p_sep_by_space     1 if a space is inserted between the currency symbol
                        and the currency value for non-negative values, 0 oth-
                        erwise.

     n_cs_precedes      Like p_cs_precedes but for negative values.

     n_sep_by_space     Like p_sep_by_space but for negative values.

     p_sign_posn        The location of the positive_sign with respect to a
                        non-negative quantity and the currency_symbol, coded
                        as follows:

                        0    Parentheses around the entire string.
                        1    Before the string.
                        2    After the string.
                        3    Just before currency_symbol.
                        4    Just after currency_symbol.

     n_sign_posn        Like p_sign_posn but for negative currency values.

     Unless mentioned above, an empty string as a value for a field indicates
     a zero length result or a value that is not in the current locale.  A
     CHAR_MAX result similarly denotes an unavailable value.

RETURN VALUES
     The setlocale() function returns NULL and fails to change the locale if
     the given combination of category and locale makes no sense.  The
     localeconv() function returns a pointer to a static object which may be
     altered by later calls to setlocale() or localeconv().

STANDARDS
     The setlocale() and localeconv() functions conform to ANSI X3.159-1989
     (``ANSI C'').

HISTORY
     The setlocale() and localeconv() functions first appeared in 4.4BSD.

BUGS
     The current implementation supports only the "C" and "POSIX" locales for
     all but the LC_CTYPE locale.

     In spite of the gnarly currency support in localeconv(), the standards
     don't include any functions for generalized currency formatting.

     LC_COLLATE does not make sense for many languages.  Use of LC_MONETARY
     could lead to misleading results until we have a real time currency con-
     version function.  LC_NUMERIC and LC_TIME are personal choices and should
     not be wrapped up with the other categories.

OpenBSD 2.6                      June 9, 1993                                3