_mbctolower, _mbctolower_l, _mbctoupper, _mbctoupper_l

Article
06/05/2017

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The latest version of this topic can be found at _mbctolower, _mbctolower_l, _mbctoupper, _mbctoupper_l.

Tests and converts the case of a multibyte character.

Important

This API cannot be used in applications that execute in the Windows Runtime. For more information, see CRT functions not supported with /ZW.

Syntax

unsigned int _mbctolower(  
   unsigned int c   
);  
unsigned int _mbctolower_l(  
   unsigned int c,  
   _locale_t locale  
);  
unsigned int _mbctoupper(  
   unsigned int c   
);  
unsigned int _mbctoupper_l(  
   unsigned int c,  
   _locale_t locale  
);

Parameters

c
Multibyte character to convert.

locale
Locale to use.

Return Value

Each of these functions returns the converted character c, if possible. Otherwise it returns the character c unchanged.

Remarks

The functions test a character c and, if possible, apply one of the following conversions.

Routines	Converts
`_mbctolower,_mbctolower_l`	Uppercase character to lowercase character.
`_mbctoupper,_mbctoupper_l`	Lowercase character to uppercase character.

The output value is affected by the setting of the LC_CTYPE category setting of the locale; see setlocale for more information. The version of this function without the _l suffix uses the current locale for this locale-dependent behavior; the version with the _l suffix is identical except that it uses the locale parameter passed in instead. For more information, see Locale.

In previous versions, _mbctolower was calledjtolower, and _mbctoupper was called jtoupper. For new code, use the new names instead.

Generic-Text Routine Mappings

Tchar.h routine	_UNICODE and _MBCS not defined	_MBCS defined	_UNICODE defined
`_totlower`	`tolower`	`_mbctolower`	`towlower`
`_totlower_l`	`_tolower_l`	`_mbctolower_l`	`_towlower_t`
`_totupper`	`toupper`	`_mbctoupper`	`towupper`
`_totupper_l`	`toupper_l`	`_mbctoupper_l`	`_towupper_l`

Requirements

Routines	Required header
`_mbctolower,_mbctolower_l`	<mbstring.h>
`_mbctoupper,_mbctoupper_l`	<mbstring.h>

For more compatibility information, see Compatibility.