isblank, iswblank, _isblank_l, _iswblank_l

Determines whether an integer represents a blank character.

Syntax

int isblank(
   int c
);
int iswblank(
   wint_t c
);
int _isblank_l(
   int c,
   _locale_t locale
);
int _iswblank_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 a space or horizontal tab character, or is one of a locale-specific set of characters that are used to separate words within a line of text. isblank returns a nonzero value if c is a space character (0x20) or horizontal tab character (0x09). The result of the test condition for the isblank functions depends on the LC_CTYPE category setting of the locale; for more information, see setlocale, _wsetlocale. The versions of these functions that don't have the _l suffix use the current locale for any locale-dependent behavior; the versions that do have the _l suffix are identical except that they use the locale that's passed in instead. For more information, see Locale.

iswblank returns a nonzero value if c is a wide character that corresponds to a standard space or horizontal tab character.

The behavior of isblank and _isblank_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