toupper, _toupper, towupper, _toupper_l, _towupper_l

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Convert character to uppercase.

Syntax

int toupper(  
   int c   
);  
int _toupper(  
   int c   
);  
int towupper(  
   wint_t c   
);  
int _toupper_l(  
   int c ,  
   _locale_t locale  
);  
int _towupper_l(  
   wint_t c ,  
   _locale_t locale  
);  

Parameters

c
Character to convert.

locale
Locale to use.

Return Value

Each of these routines converts a copy of c, if possible, and returns the result.

If c is a wide character for which iswlower is nonzero and there is a corresponding wide character for which iswupper is nonzero, towupper returns the corresponding wide character; otherwise, towupper returns c unchanged.

There is no return value reserved to indicate an error.

In order for toupper to give the expected results, __isascii and islower must both return nonzero.

Remarks

Each of these routines converts a given lowercase letter to an uppercase letter if possible and appropriate. The case conversion of towupper is locale-specific. Only the characters relevant to the current locale are changed in case. The functions without the _l suffix use the currently set locale. The versions of these functions with the _l suffix take the locale as a parameter and use that instead of the currently set locale. For more information, see Locale.

In order for toupper to give the expected results, __isascii and isupper must both return nonzero.

Data Conversion Routines

Generic-Text Routine Mappings

Requirements

For additional compatibility information, see Compatibility in the Introduction.

Example

See the example in to Functions.

.NET Framework Equivalent

System::Char::ToUpper

See Also

is, isw Routines
to Functions
Locale
Interpretation of Multibyte-Character Sequences