_mbctolower, _mbctoupper
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_mbctolower, _mbctoupper

Test and convert the case of a multibyte character.

unsigned int _mbctolower(
   unsigned int c 
unsigned int _mbctoupper(
   unsigned int c 


Multibyte character to convert.

Return Value

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


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

Routine Converts
_mbctolower Uppercase character to lowercase character
_mbctoupper Lowercase character to uppercase character

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

Generic-Text Routine Mappings

TCHAR.H routine _UNICODE & _MBCS not defined _MBCS defined _UNICODE defined
_totlower tolower _mbctolower towlower
_totupper toupper _mbctoupper towupper


Routine Required header Compatibility
_mbctolower <mbstring.h> Win 98, Win Me, Win NT, Win 2000, Win XP
_mbctoupper <mbstring.h> Win 98, Win Me, Win NT, Win 2000, Win XP

For additional compatibility information, see Compatibility in the Introduction.


All versions of the C run-time libraries.

See Also

Data Conversion Routines | _mbbtombc | _mbcjistojms | _mbctohira | _mbctombb | Run-Time Routines and .NET Framework Equivalents

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