User  |  Syst  |  Libr  |  Device  |  Files  |  Other  |  Admin  |  Head  |

---

   duplocale    ( 3 )

---

---

Имя (Name)

duplocale - duplicate a locale object

---

Синопсис (Synopsis)

#include <locale.h>

locale_t duplocale(locale_t locobj);

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

duplocale(): Since glibc 2.10: _XOPEN_SOURCE >= 700 Before glibc 2.10: _GNU_SOURCE

---

Описание (Description)

The duplocale() function creates a duplicate of the locale object referred to by locobj.

If locobj is LC_GLOBAL_LOCALE, duplocale() creates a locale object containing a copy of the global locale determined by setlocale(3).

---

Возвращаемое значение (Return value)

On success, duplocale() returns a handle for the new locale object. On error, it returns (locale_t) 0, and sets errno to indicate the error.

---

Ошибки (Error)

ENOMEM Insufficient memory to create the duplicate locale object.

---

Версии (Versions)

The duplocale() function first appeared in version 2.3 of the GNU C library.

---

Стандарты (Conforming to)

POSIX.1-2008.

---

Примечание (Note)

Duplicating a locale can serve the following purposes:

* To create a copy of a locale object in which one of more categories are to be modified (using newlocale(3)).

* To obtain a handle for the current locale which can used in other functions that employ a locale handle, such as toupper_l(3). This is done by applying duplocale() to the value returned by the following call:

loc = uselocale((locale_t) 0);

This technique is necessary, because the above uselocale(3) call may return the value LC_GLOBAL_LOCALE, which results in undefined behavior if passed to functions such as toupper_l(3). Calling duplocale() can be used to ensure that the LC_GLOBAL_LOCALE value is converted into a usable locale object. See EXAMPLES, below.

Each locale object created by duplocale() should be deallocated using freelocale(3).

---

Примеры (Examples)

The program below uses uselocale(3) and duplocale() to obtain a
       handle for the current locale which is then passed to
       toupper_l(3).  The program takes one command-line argument, a
       string of characters that is converted to uppercase and displayed
       on standard output.  An example of its use is the following:

           $ ./a.out abc
           ABC

   Program source

       #define _XOPEN_SOURCE 700
       #include <ctype.h>
       #include <stdio.h>
       #include <stdlib.h>
       #include <locale.h>

       #define errExit(msg)    do { perror(msg); exit(EXIT_FAILURE); \
                               } while (0)

       int
       main(int argc, char *argv[])
       {
           locale_t loc, nloc;

           if (argc != 2) {
               fprintf(stderr, "Usage: %s string\n", argv[0]);
               exit(EXIT_FAILURE);
           }

           /* This sequence is necessary, because uselocale() might return
              the value LC_GLOBAL_LOCALE, which can't be passed as an
              argument to toupper_l(). */

           loc = uselocale((locale_t) 0);
           if (loc == (locale_t) 0)
               errExit("uselocale");

           nloc = duplocale(loc);
           if (nloc == (locale_t) 0)
               errExit("duplocale");

           for (char *p = argv[1]; *p; p++)
               putchar(toupper_l(*p, nloc));

           printf("\n");

           freelocale(nloc);

           exit(EXIT_SUCCESS);
       }

---

Смотри также (See also)

freelocale(3), newlocale(3), setlocale(3), uselocale(3), locale(5), locale(7)

---