isupper, _isupper_l, iswupper, _iswupper_l

Determines whether an integer represents an uppercase character.

Syntax

int isupper(
   int c
);
int _isupper_l (
   int c,
   _locale_t locale
);
int iswupper(
   wint_t c
);
int _iwsupper_l(
   wint_t c,
   _locale_t locale
);

Parameters

c
Integer to test.

locale
Locale to use.

Return value

Each of these routines returns nonzero if c is a particular representation of an uppercase letter. isupper returns a nonzero value if c is an uppercase character (A - Z). iswupper returns a nonzero value if c is a wide character that corresponds to an uppercase letter, or if c is one of an implementation-defined set of wide characters for which none of iswcntrl, iswdigit, iswpunct, or iswspace is nonzero. Each of these routines returns 0 if c doesn't satisfy the test condition.

The versions of these functions that have the _l suffix use the locale that's passed in instead of the current locale for their locale-dependent behavior. For more information, see Locale.

The behavior of isupper and _isupper_l is undefined if c isn't EOF or in the range 0 through 0xFF, inclusive. When a debug CRT library is used and c isn't one of these values, the functions raise an assertion.

Generic-text routine mappings

Remarks

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

Requirements

For more compatibility information, see Compatibility.

See also

Character classification
Locale
is, isw routines