NAME

nl_langinfo, nl_langinfo_l - language information

SYNOPSIS

#include <langinfo.h>

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


DESCRIPTION

The nl_langinfo() and nl_langinfo_l() functions shall return a pointer to a string containing information relevant to the particular language or cultural area defined in the locale of the process, or in the locale represented by locale, respectively (see <langinfo.h>). The manifest constant names and values of item are defined in <langinfo.h>. For example:

nl_langinfo(ABDAY_1)

would return a pointer to the string "Dom" if the identified language was Portuguese, and "Sun" if the identified language was English.

nl_langinfo_l(ABDAY_1, loc)

would return a pointer to the string "Dom" if the identified language of the locale represented by loc was Portuguese, and "Sun" if the identified language of the locale represented by loc was English.

Calls to setlocale() with a category corresponding to the category of item (see <langinfo.h>), or to the category LC_ALL , may overwrite the array pointed to by the return value. Calls to uselocale() which change the category corresponding to the category of item may overwrite the array pointed to by the return value.

The nl_langinfo() function need not be thread-safe.

RETURN VALUE

In a locale where langinfo data is not defined, these functions shall return a pointer to the corresponding string in the POSIX locale. In all locales, these functions shall return a pointer to an empty string if item contains an invalid setting.

This pointer may point to static data that may be overwritten on the next call to either function.

ERRORS

The nl_langinfo_l() function may fail if:

[EINVAL]

locale is not a valid locale object handle.

EXAMPLES

Getting Date and Time Formatting Information

The following example returns a pointer to a string containing date and time formatting information, as defined in the LC_TIME category of the current locale.

#include <time.h>
#include <langinfo.h>
...
strftime(datestring, sizeof(datestring), nl_langinfo(D_T_FMT), tm);
...

APPLICATION USAGE

The array pointed to by the return value should not be modified by the program, but may be modified by further calls to these functions.

RATIONALE

None.

FUTURE DIRECTIONS

None.

SEE ALSO

setlocale , uselocale

XBD Locale , <langinfo.h> , <locale.h> , <nl_types.h>

CHANGE HISTORY

First released in Issue 2.

Issue 5

The last paragraph of the DESCRIPTION is moved from the APPLICATION USAGE section.

A note indicating that this function need not be reentrant is added to the DESCRIPTION.

Issue 7

Austin Group Interpretation 1003.1-2001 #156 is applied.

The nl_langinfo() function is moved from the XSI option to the Base.

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