NAME

langinfo.h — language information constants

SYNOPSIS

#include <langinfo.h>

DESCRIPTION

The <langinfo.h> header shall define the symbolic constants used to identify items of langinfo data (see nl_langinfo(3)).

The <langinfo.h> header shall define the locale_t type as described in <locale.h>.

The <langinfo.h> header shall define the nl_item type as described in <nl_types.h>.

The <langinfo.h> header shall define the following symbolic constants with type nl_item. The entries under Category indicate in which setlocale(3) category each item is defined.

Constant	Category	Meaning
CODESET	LC_CTYPE	Codeset name.
D_T_FMT	LC_TIME	String for formatting date and time.
D_FMT	LC_TIME	Date format string.
T_FMT	LC_TIME	Time format string.
T_FMT_AMPM	LC_TIME	Time format string using 12-hour clock format, if supported in the locale; if the 12-hour format is not supported, this shall be either an empty string or a string specifying a 24-hour clock format.
AM_STR	LC_TIME	Ante-meridiem affix; if AM_STR and PM_STR are both empty strings, the 12-hour format is not supported in the locale.
PM_STR	LC_TIME	Post-meridiem affix; if AM_STR and PM_STR are both empty strings, the 12-hour format is not supported in the locale.
DAY_1	LC_TIME	Name of the first day of the week (for example, Sunday).
DAY_2	LC_TIME	Name of the second day of the week (for example, Monday).
DAY_3	LC_TIME	Name of the third day of the week (for example, Tuesday).
DAY_4	LC_TIME	Name of the fourth day of the week (for example, Wednesday).
DAY_5	LC_TIME	Name of the fifth day of the week (for example, Thursday).
DAY_6	LC_TIME	Name of the sixth day of the week (for example, Friday).
DAY_7	LC_TIME	Name of the seventh day of the week (for example, Saturday).
ABDAY_1	LC_TIME	Abbreviated name of the first day of the week.
ABDAY_2	LC_TIME	Abbreviated name of the second day of the week.
ABDAY_3	LC_TIME	Abbreviated name of the third day of the week.
ABDAY_4	LC_TIME	Abbreviated name of the fourth day of the week.
ABDAY_5	LC_TIME	Abbreviated name of the fifth day of the week.
ABDAY_6	LC_TIME	Abbreviated name of the sixth day of the week.
ABDAY_7	LC_TIME	Abbreviated name of the seventh day of the week.
MON_1	LC_TIME	Name of the first month of the year.
MON_2	LC_TIME	Name of the second month.
MON_3	LC_TIME	Name of the third month.
MON_4	LC_TIME	Name of the fourth month.
MON_5	LC_TIME	Name of the fifth month.
MON_6	LC_TIME	Name of the sixth month.
MON_7	LC_TIME	Name of the seventh month.
MON_8	LC_TIME	Name of the eighth month.
MON_9	LC_TIME	Name of the ninth month.
MON_10	LC_TIME	Name of the tenth month.
MON_11	LC_TIME	Name of the eleventh month.
MON_12	LC_TIME	Name of the twelfth month.
ALTMON_1	LC_TIME	Name of the alternative appropriate first month of the year.
ALTMON_2	LC_TIME	Name of the alternative appropriate second month.
ALTMON_3	LC_TIME	Name of the alternative appropriate third month.
ALTMON_4	LC_TIME	Name of the alternative appropriate fourth month.
ALTMON_5	LC_TIME	Name of the alternative appropriate fifth month.
ALTMON_6	LC_TIME	Name of the alternative appropriate sixth month.
ALTMON_7	LC_TIME	Name of the alternative appropriate seventh month.
ALTMON_8	LC_TIME	Name of the alternative appropriate eighth month.
ALTMON_9	LC_TIME	Name of the alternative appropriate ninth month.
ALTMON_10	LC_TIME	Name of the alternative appropriate tenth month.
ALTMON_11	LC_TIME	Name of the alternative appropriate eleventh month.
ALTMON_12	LC_TIME	Name of the alternative appropriate twelfth month.
ABMON_1	LC_TIME	Abbreviated name of the first month.
ABMON_2	LC_TIME	Abbreviated name of the second month.
ABMON_3	LC_TIME	Abbreviated name of the third month.
ABMON_4	LC_TIME	Abbreviated name of the fourth month.
ABMON_5	LC_TIME	Abbreviated name of the fifth month.
ABMON_6	LC_TIME	Abbreviated name of the sixth month.
ABMON_7	LC_TIME	Abbreviated name of the seventh month.
ABMON_8	LC_TIME	Abbreviated name of the eighth month.
ABMON_9	LC_TIME	Abbreviated name of the ninth month.
ABMON_10	LC_TIME	Abbreviated name of the tenth month.
ABMON_11	LC_TIME	Abbreviated name of the eleventh month.
ABMON_12	LC_TIME	Abbreviated name of the twelfth month.
ABALTMON_1	LC_TIME	Abbreviated alternative name of the first month of the year.
ABALTMON_2	LC_TIME	Abbreviated alternative name of the second month.
ABALTMON_3	LC_TIME	Abbreviated alternative name of the third month.
ABALTMON_4	LC_TIME	Abbreviated alternative name of the fourth month.
ABALTMON_5	LC_TIME	Abbreviated alternative name of the fifth month.
ABALTMON_6	LC_TIME	Abbreviated alternative name of the sixth month.
ABALTMON_7	LC_TIME	Abbreviated alternative name of the seventh month.
ABALTMON_8	LC_TIME	Abbreviated alternative name of the eighth month.
ABALTMON_9	LC_TIME	Abbreviated alternative name of the ninth month.
ABALTMON_10	LC_TIME	Abbreviated alternative name of the tenth month.
ABALTMON_11	LC_TIME	Abbreviated alternative name of the eleventh month.
ABALTMON_12	LC_TIME	Abbreviated alternative name of the twelfth month.
ERA	LC_TIME	Era description segments.
ERA_D_FMT	LC_TIME	Era date format string.
ERA_D_T_FMT	LC_TIME	Era date and time format string.
ERA_T_FMT	LC_TIME	Era time format string.
ALT_DIGITS	LC_TIME	Alternative symbols for digits.
RADIXCHAR	LC_NUMERIC	Radix character.
THOUSEP	LC_NUMERIC	Separator for thousands.
YESEXPR	LC_MESSAGES	Affirmative response expression.
NOEXPR	LC_MESSAGES	Negative response expression.
CRNCYSTR	LC_MONETARY	Local currency symbol, preceded by '-' if the symbol should appear before the value, '+' if the symbol should appear after the value, or '.' if the symbol should replace the radix character. If the local currency symbol is the empty string, implementations may return the empty string ("").

If the locale's values for p_cs_precedes and n_cs_precedes do not match, the value of nl_langinfo (CRNCYSTR) and nl_langinfo_l (CRNCYSTR,loc) is unspecified.

The following shall be declared as a function and may also be defined as a macro. A function prototype shall be provided.

char *nl_langinfo(nl_item);
char *nl_langinfo_l(nl_item, locale_t);

Inclusion of the <langinfo.h> header may also make visible all symbols from <nl_types.h>.

The following sections are informative.

APPLICATION USAGE

Wherever possible, users are advised to use functions compatible with those in the ISO C standard to access items of langinfo data. In particular, the strftime(3) function should be used to access date and time information defined in category LC_TIME . The localeconv(3) function should be used to access information corresponding to RADIXCHAR, THOUSEP, and CRNCYSTR.

RATIONALE

None.

FUTURE DIRECTIONS

None.

CHANGE HISTORY

First released in Issue 2.

Issue 5

The constants YESSTR and NOSTR are marked LEGACY.

Issue 6

The constants YESSTR and NOSTR are removed.

IEEE Std 1003.1-2001 (“POSIX.1”)/Cor 1-2002, item XBD/TC1/D6/9 is applied, adding a sentence to the "Meaning" column entry for the CRNCYSTR constant. This change is to accommodate historic practice.

Issue 7

The <langinfo.h> header is moved from the XSI option to the Base.

The nl_langinfo_l(3) function is added from The Open Group Technical Standard, 2006, Extended API Set Part 4.

This reference page is clarified with respect to macros and symbolic constants, and a declaration for the locale_t type is added.

POSIX.1-2008, Technical Corrigendum 1, XBD/TC1-2008/0051 [107] is applied.

Issue 8

Austin Group Defects 258 and 1166 are applied, adding the ALTMON_ x and ABALTMON_ x symbolic constants.

Austin Group Defect 1307 is applied, changing the AM_STR, PM_STR, and T_FMT_AMPM constants in relation to locales that do not support the 12-hour clock format.

End of informative text.