Locale

Article
04/28/2015

Locale refers to country/region and language settings that you can use to customize your program. Some locale-dependent categories include the display formats for dates and monetary values. For more information, see Locale Categories.

Use the setlocale function to change or query some or all of the current program or thread locale information while using functions without the _l suffix. The functions with the _l suffix will use the locale parameter passed in for their locale information during the execution of that specific function only. To create a locale for use with a function with a _l suffix, use _create_locale. To free this locale, use _free_locale. To get the current locale, use _get_current_locale.

Use _configthreadlocale to control whether each thread has its own locale, or all threads in a program share the same locale. For more information, see Locales and Code Pages.

More secure versions of the functions in the following table are available, indicated by the _s ("secure") suffix. For more information, see Security Features in the CRT.

Locale-Dependent Routines

Routine	Use	setlocale category setting dependence
atof, _atof_l, _wtof, _wtof_l	Convert character to floating-point value	LC_NUMERIC
atoi, _atoi_l, _wtoi, _wtoi_l	Convert character to integer value	LC_NUMERIC
_atoi64, _atoi64_l, _wtoi64, _wtoi64_l	Convert character to 64-bit integer value	LC_NUMERIC
atol, _atol_l, _wtol, _wtol_l	Convert character to long value	LC_NUMERIC
_atodbl, _atodbl_l, _atoldbl, _atoldbl_l, _atoflt _atoflt_l	Convert character to double-long value	LC_NUMERIC
is Routines	Test given integer for particular condition.	LC_CTYPE
isleadbyte, _isleadbyte_l	Test for lead byte	LC_CTYPE
localeconv	Read appropriate values for formatting numeric quantities	LC_MONETARY, LC_NUMERIC
MB_CUR_MAX	Maximum length in bytes of any multibyte character in current locale (macro defined in STDLIB.H)	LC_CTYPE
_mbccpy, _mbccpy_l,_mbccpy_s, _mbccpy_s_l	Copy one multibyte character	LC_CTYPE
_mbclen, mblen, _mblen_l	Validate and return number of bytes in multibyte character	LC_CTYPE
strlen, wcslen, _mbslen, _mbslen_l, _mbstrlen, _mbstrlen_l	For multibyte-character strings: validate each character in string; return string length	LC_CTYPE
mbstowcs, _mbstowcs_l,mbstowcs_s, _mbstowcs_s_l	Convert sequence of multibyte characters to corresponding sequence of wide characters	LC_CTYPE
mbtowc, _mbtowc_l	Convert multibyte character to corresponding wide character	LC_CTYPE
printf functions	Write formatted output	LC_NUMERIC (determines radix character output)
scanf functions	Read formatted input	LC_NUMERIC (determines radix character recognition)
setlocale, _wsetlocale	Select locale for program	Not applicable
strcoll, wcscoll, _mbscoll, _strcoll_l, _wcscoll_l, _mbscoll_l	Compare characters of two strings	LC_COLLATE
_stricmp, _wcsicmp, _mbsicmp, _stricmp_l, _wcsicmp_l, _mbsicmp_l	Compare two strings without regard to case	LC_CTYPE
_stricoll, _wcsicoll, _mbsicoll, _stricoll_l, _wcsicoll_l, _mbsicoll_l	Compare characters of two strings (case insensitive)	LC_COLLATE
_strncoll, _wcsncoll, _mbsncoll, _strncoll_l, _wcsncoll_l, _mbsncoll_l	Compare first n characters of two strings	LC_COLLATE
_strnicmp, _wcsnicmp, _mbsnicmp, _strnicmp_l, _wcsnicmp_l, _mbsnicmp_l	Compare characters of two strings without regard to case.	LC_CTYPE
_strnicoll, _wcsnicoll, _mbsnicoll, _strnicoll_l, _wcsnicoll_l, _mbsnicoll_l	Compare first n characters of two strings (case insensitive)	LC_COLLATE
strftime, wcsftime, _strftime_l, _wcsftime_l	Format date and time value according to supplied format argument	LC_TIME
_strlwr, _wcslwr, _mbslwr, _strlwr_l, _wcslwr_l, _mbslwr_l,_strlwr_s, _strlwr_s_l, _mbslwr_s, _mbslwr_s_l, _wcslwr_s, _wcslwr_s_l	Convert, in place, each uppercase letter in given string to lowercase	LC_CTYPE
strtod, _strtod_l, wcstod, _wcstod_l	Convert character string to double value	LC_NUMERIC (determines radix character recognition)
strtol, wcstol, _strtol_l, _wcstol_l	Convert character string to longvalue	LC_NUMERIC (determines radix character recognition)
strtoul, _strtoul_l, wcstoul, _wcstoul_l	Convert character string to unsigned long value	LC_NUMERIC (determines radix character recognition)
_strupr, _strupr_l, _mbsupr, _mbsupr_l, _wcsupr_l, _wcsupr,_strupr_s, _strupr_s_l, _mbsupr_s, _mbsupr_s_l, _wcsupr_s, _wcsupr_s_l	Convert, in place, each lowercase letter in string to uppercase	LC_CTYPE
strxfrm, wcsxfrm, _strxfrm_l, _wcsxfrm_l	Transform string into collated form according to locale	LC_COLLATE
tolower, _tolower, towlower, _tolower_l, _towlower_l,_mbctolower, _mbctolower_l, _mbctoupper, _mbctoupper_l	Convert given character to corresponding lowercase character	LC_CTYPE
toupper, _toupper, towupper, _toupper_l, _towupper_l,_mbctolower, _mbctolower_l, _mbctoupper, _mbctoupper_l	Convert given character to corresponding uppercase letter	LC_CTYPE
wcstombs, _wcstombs_l,wcstombs_s, _wcstombs_s_l	Convert sequence of wide characters to corresponding sequence of multibyte characters	LC_CTYPE
wctomb, _wctomb_l,wctomb_s, _wctomb_s_l	Convert wide character to corresponding multibyte character	LC_CTYPE

Note

For multibyte routines, the multibyte code page must be equivalent to the locale set with setlocale. _setmbcp, with an argument of _MB_CP_LOCALE makes the multibyte code page the same as the setlocale code page.

Locale

See Also

Reference

Additional resources