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isspace, iswspace, _isspace_l, _iswspace_l


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The latest version of this topic can be found at isspace, iswspace, _isspace_l, _iswspace_l.

Determines whether an integer represents a space character.

int isspace(  
   int c   
int iswspace(  
   wint_t c   
int _isspace_l(  
   int c,  
   _locale_t locale  
int _iswspace_l(  
   wint_t c,  
   _locale_t locale  


Integer to test.

Locale to use.

Each of these routines returns nonzero if c is a particular representation of a space character. isspace returns a nonzero value if c is a white-space character (0x09 – 0x0D or 0x20). The result of the test condition for the isspace function depends on the LC_CTYPE category setting of the locale; see setlocale, _wsetlocale for more information. The versions of these functions that do not 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.

iswspace returns a nonzero value if c is a wide character that corresponds to a standard white-space character.

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

Generic-Text Routine Mappings

TCHAR.H routine_UNICODE & _MBCS not defined_MBCS defined_UNICODE defined
_ istspaceisspace_ismbcspaceiswspace
RoutineRequired header
iswspace<ctype.h> or <wchar.h>
_iswspace_l<ctype.h> or <wchar.h>

For additional compatibility information, see Compatibility.


Character Classification
is, isw Routines