locale.h setLocale

 前一篇文章 中，宽字符集 打印中文，还需要设置 locale

locale.h 也不多，附上 头文件的源码

/***
*locale.h - definitions/declarations for localization routines
*
*       Copyright (c) Microsoft Corporation. All rights reserved.
*
*Purpose:
*       This file defines the structures, values, macros, and functions
*       used by the localization routines.
*
*       [Public]
*
****/

#pragma once

#ifndef _INC_LOCALE
#define _INC_LOCALE

#include <crtdefs.h>

/*
 * Currently, all MS C compilers for Win32 platforms default to 8 byte
 * alignment.
 */
#pragma pack(push,_CRT_PACKING)

#ifdef  __cplusplus
extern "C" {
#endif

/* define NULL pointer value */
#ifndef NULL
#ifdef __cplusplus
#define NULL    0
#else
#define NULL    ((void *)0)
#endif
#endif

/* Locale categories */

#define LC_ALL          0
#define LC_COLLATE      1
#define LC_CTYPE        2
#define LC_MONETARY     3
#define LC_NUMERIC      4
#define LC_TIME         5

#define LC_MIN          LC_ALL
#define LC_MAX          LC_TIME

/* Locale convention structure */

#ifndef _LCONV_DEFINED
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;
        wchar_t *_W_decimal_point;
        wchar_t *_W_thousands_sep;
        wchar_t *_W_int_curr_symbol;
        wchar_t *_W_currency_symbol;
        wchar_t *_W_mon_decimal_point;
        wchar_t *_W_mon_thousands_sep;
        wchar_t *_W_positive_sign;
        wchar_t *_W_negative_sign;
        };
#define _LCONV_DEFINED
#endif

/* ANSI: char lconv members default is CHAR_MAX which is compile time
   dependent. Defining and using _charmax here causes CRT startup code
   to initialize lconv members properly */

#ifdef  _CHAR_UNSIGNED
extern int _charmax;
extern __inline int __dummy(void) { return _charmax; }
#endif

/* function prototypes */

#ifndef _CONFIG_LOCALE_SWT
#define _ENABLE_PER_THREAD_LOCALE           0x1
#define _DISABLE_PER_THREAD_LOCALE          0x2
#define _ENABLE_PER_THREAD_LOCALE_GLOBAL    0x10
#define _DISABLE_PER_THREAD_LOCALE_GLOBAL   0x20
#define _ENABLE_PER_THREAD_LOCALE_NEW       0x100
#define _DISABLE_PER_THREAD_LOCALE_NEW      0x200
#define _CONFIG_LOCALE_SWT
#endif

_Check_return_opt_ _CRTIMP int __cdecl _configthreadlocale(_In_ int _Flag);
_Check_return_opt_ _CRTIMP char * __cdecl setlocale(_In_ int _Category, _In_opt_z_ const char * _Locale);
_Check_return_opt_ _CRTIMP struct lconv * __cdecl localeconv(void);
_Check_return_opt_ _CRTIMP _locale_t __cdecl _get_current_locale(void);
_Check_return_opt_ _CRTIMP _locale_t __cdecl _create_locale(_In_ int _Category, _In_z_ const char * _Locale);
_CRTIMP void __cdecl _free_locale(_In_opt_ _locale_t _Locale);

/* use _get_current_locale, _create_locale and _free_locale, instead of these functions with double leading underscore */
_Check_return_ _CRT_OBSOLETE(_get_current_locale) _CRTIMP _locale_t __cdecl __get_current_locale(void);
_Check_return_ _CRT_OBSOLETE(_create_locale) _CRTIMP _locale_t __cdecl __create_locale(_In_ int _Category, _In_z_ const char * _Locale);
_CRT_OBSOLETE(_free_locale) _CRTIMP void __cdecl __free_locale(_In_opt_ _locale_t _Locale);

#ifndef _WLOCALE_DEFINED

/* wide function prototypes, also declared in wchar.h  */

_Check_return_opt_ _CRTIMP wchar_t * __cdecl _wsetlocale(_In_ int _Category, _In_opt_z_ const wchar_t * _Locale);

#define _WLOCALE_DEFINED
#endif

#ifdef  __cplusplus
}
#endif

#pragma pack(pop)

#endif  /* _INC_LOCALE */

关于为什么 要设置locale才能在wprintf打印中文的讨论见：

http://topic.csdn.net/u/20120331/18/0e806bd0-28d4-4012-9a32-ab99cc16e554.html

（csdn某些地方 很让人讨厌）

获得当前的locale

//in crtdef.h

struct threadlocaleinfostruct;
struct threadmbcinfostruct;
typedef struct threadlocaleinfostruct * pthreadlocinfo;
typedef struct threadmbcinfostruct * pthreadmbcinfo;
struct __lc_time_data;

typedef struct localeinfo_struct
{
    pthreadlocinfo locinfo;
    pthreadmbcinfo mbcinfo;
} _locale_tstruct, *_locale_t;


//
_locale_t ret=_get_current_locale();

_free_locale(ret);

typedef struct threadlocaleinfostruct {
        int refcount;
        unsigned int lc_codepage;
        unsigned int lc_collate_cp;
        unsigned long lc_handle[6]; /* LCID */
        LC_ID lc_id[6];
        struct {
            char *locale;
            wchar_t *wlocale;
            int *refcount;
            int *wrefcount;
        } lc_category[6];
        int lc_clike;
        int mb_cur_max;
        int * lconv_intl_refcount;
        int * lconv_num_refcount;
        int * lconv_mon_refcount;
        struct lconv * lconv;
        int * ctype1_refcount;
        unsigned short * ctype1;
        const unsigned short * pctype;
        const unsigned char * pclmap;
        const unsigned char * pcumap;
        struct __lc_time_data * lc_time_curr;
} threadlocinfo;

threadmbcinfostruct这个结构体 暂时没有找到。
如何打印出来 _locale_t 指针所代表的 locale 也不知道。

setLocale的返回值

        char   *old_locale; 
        old_locale   =   setlocale(LC_ALL, ""); //setlocale(LC_CTYPE, NULL);  
        printf( "Old   locale   was   :\n%s\n ",old_locale); 

设置locale

setlocale(LC_CTYPE, "chs");

//下面的代码 意思 也不太清楚
TCHAR szACP[16];

wsprintf(szACP, _T(".%d"), GetACP());

_tsetlocale(LC_CTYPE, szACP);

setlocale(LC_CTYPE, "");

反正 用处 也不是很多。

只要知道 如何 wprintf 输出中文的时候就行了。