forked from KolibriOS/kolibrios
754f9336f0
git-svn-id: svn://kolibrios.org@4349 a494cfbc-eb01-0410-851d-a64ba20cac60
44 lines
874 B
C
44 lines
874 B
C
/*
|
|
FUNCTION
|
|
<<isdigit>>---decimal digit predicate
|
|
|
|
INDEX
|
|
isdigit
|
|
|
|
ANSI_SYNOPSIS
|
|
#include <ctype.h>
|
|
int isdigit(int <[c]>);
|
|
|
|
TRAD_SYNOPSIS
|
|
#include <ctype.h>
|
|
int isdigit(<[c]>);
|
|
|
|
DESCRIPTION
|
|
<<isdigit>> is a macro which classifies ASCII integer values by table
|
|
lookup. It is a predicate returning non-zero for decimal digits, and 0 for
|
|
other characters. It is defined only when <<isascii>>(<[c]>) is true
|
|
or <[c]> is EOF.
|
|
|
|
You can use a compiled subroutine instead of the macro definition by
|
|
undefining the macro using `<<#undef isdigit>>'.
|
|
|
|
RETURNS
|
|
<<isdigit>> returns non-zero if <[c]> is a decimal digit (<<0>>--<<9>>).
|
|
|
|
PORTABILITY
|
|
<<isdigit>> is ANSI C.
|
|
|
|
No supporting OS subroutines are required.
|
|
*/
|
|
|
|
#include <_ansi.h>
|
|
#include <ctype.h>
|
|
|
|
|
|
#undef isdigit
|
|
int
|
|
_DEFUN(isdigit,(c),int c)
|
|
{
|
|
return(__ctype_ptr__[c+1] & _N);
|
|
}
|