toupper, _toupper, towupper, _toupper_l, _towupper_l

• 4/2/2020
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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

By default, this function's global state is scoped to the application. To change this, see Global state in the CRT.

Generic-Text Routine Mappings

Requirements

For additional compatibility information, see Compatibility.

Example

See the example in to Functions.

See also

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