isascii
, __isascii
, iswascii
Determines whether a particular character is an ASCII character.
Syntax
int __isascii(
int c
);
int iswascii(
wint_t c
);
#define isascii __isascii
Parameters
c
Integer to test.
Return value
Each of these routines returns nonzero if c
is a particular representation of an ASCII character. __isascii
returns a nonzero value if c
is an ASCII character (in the range 0x00 - 0x7F). iswascii
returns a nonzero value if c
is a wide-character representation of an ASCII character. Each of these routines returns 0 if c
doesn't satisfy the test condition.
Remarks
Both __isascii
and iswascii
are implemented as macros unless the preprocessor macro _CTYPE_DISABLE_MACROS
is defined.
For backward compatibility, isascii
is implemented as a macro only if __STDC__
isn't defined or is defined as 0; otherwise it's undefined.
By default, this function's global state is scoped to the application. To change this scope, see Global state in the CRT.
Generic-text routine mappings
Tchar.h routine | _UNICODE and _MBCS not defined |
_MBCS defined |
_UNICODE defined |
---|---|---|---|
_istascii |
__isascii |
__isascii |
iswascii |
Requirements
Routine | Required header |
---|---|
isascii , __isascii |
C: <ctype.h> C++: <cctype> or <ctype.h> |
iswascii |
C: <wctype.h>, <ctype.h>, or <wchar.h> C++: <cwctype>, <cctype>, <wctype.h>, <ctype.h>, or <wchar.h> |
The isascii
, __isascii
, and iswascii
functions are Microsoft-specific. For more compatibility information, see Compatibility.