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iscntrl, iswcntrl, _iscntrl_l, _iswcntrl_l

Determine if an integer represents a control character.

int iscntrl( 
   int c 
);
int iswcntrl( 
   wint_t c 
);
int _iscntrl_l( 
   int c,
   _locale_t locale
);
int _iswcntrl_l( 
   wint_t c,
   _locale_t locale
);

Parameters

  • c
    Integer to test

  • locale
    The locale to use.

Return Value

Each of these routines returns nonzero if c is a particular representation of a control character. iscntrl returns a nonzero value if c is a control character (0x00 – 0x1F or 0x7F). iswcntrl returns a nonzero value if c is a control wide character. Each of these routines returns 0 if c does not satisfy the test condition.

When used with a debug CRT library, iscntrl will display a CRT assert if passed a parameter that is not EOF or in the range of 0 through 0xFF. When used with a debug CRT library, iscntrl will use the parameter as an index into an array, with undefined results if the parameter is not EOF or in the range of 0 through 0xFF.

The versions of these functions with the _l suffix are identical except that they use the locale parameter passed in instead of the current locale. For more information, see Locale.

Generic-Text Routine Mappings

TCHAR.H routine

_UNICODE & _MBCS not defined

_MBCS defined

_UNICODE defined

_istcntrl

iscntrl

iscntrl

iswcntrl

_istcntrl_l

_iscntrl_l

_iscntrl_l

_iswcntrl_l

Requirements

Routine

Required header

iscntrl

<ctype.h>

iswcntrl

<ctype.h> or <wchar.h>

_iscntrl_l

<ctype.h>

_iswcntrl_l

<ctype.h> or <wchar.h>

For additional compatibility information, see Compatibility in the Introduction.

.NET Framework Equivalent

System::Char::IsControl

See Also

Reference

Character Classification

Locale

is, isw Routines