The <locale.h> include file declares the setlocale(), localeconv(), and wcslocaleconv() library functions. These functions are useful for changing the C locale when you are creating applications for international markets.
The <locale.h> include file also declares the type struct lconv and the following macro definitions:
| NULL | LC_ALL | LC_C | LC_C_FRANCE |
| LC_C_GERMANY | LC_C_ITALY | LC_C_SPAIN | LC_C_UK |
| LC_C_USA | LC_COLLATE | LC_CTYPE | LC_MESSAGES |
| LC_MONETARY | LC_NUMERIC | LC_TIME | LC_TOD |
| LC_UCS2_ALL | LC_UCS2_COLLATE | LC_UCS2_CTYPE | LC_UNI_ALL |
| LC_UNI_COLLATE | LC_UNI_CTYPE | LC_UNI_TIME | LC_UNI_NUMERIC |
| LC_UNI_MESSAGES | LC_UNI_MONITARY | LC_UNI_TOD |