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isdigit, iswdigit

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intisdigit(intc**);**

intiswdigit(wint_tc**);**

Each of these routines returns true if c is a particular representation of a decimal-digit character.

Routine Required Header Compatibility
isdigit <ctype.h> ANSI, Win 95, Win NT
iswdigit <ctype.h> or <wchar.h> ANSI, Win 95, Win NT

For additional compatibility information, see Compatibility in the Introduction.

Libraries

LIBC.LIB Single thread static library, retail version
LIBCMT.LIB Multithread static library, retail version
MSVCRT.LIB Import library for MSVCRT.DLL, retail version

Return Value

isdigit returns a non-zero value if c is a decimal digit (0 – 9). iswdigit returns a non-zero value if c is a wide character corresponding to a decimal-digit character. Each of these routines returns 0 if c does not satisfy the test condition.

The result of the test condition for the isdigit function depends on the LC_CTYPE category setting of the current locale; see setlocale for more information. For iswdigit, the result of the test condition is independent of locale.

Parameter

c

Integer to test

Generic-Text Routine Mappings

TCHAR.H Routine _UNICODE & _MBCS Not Defined _MBCS Defined _UNICODE Defined
_istdigit isdigit _ismbcdigit iswdigit

Character Classification Routines |  Locale Routines |  is, isw Function Overview