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/*
FUNCTION
<<isxdigit>>---hexadecimal digit predicate
INDEX
isxdigit
ANSI_SYNOPSIS
#include <ctype.h>
int isxdigit(int <[c]>);
TRAD_SYNOPSIS
#include <ctype.h>
int isxdigit(int <[c]>);
DESCRIPTION
<<isxdigit>> is a macro which classifies ASCII integer values by table
lookup. It is a predicate returning non-zero for hexadecimal digits,
and <<0>> for other characters. It is defined only if <[c]> is
representable as an unsigned char or if <[c]> is EOF.
You can use a compiled subroutine instead of the macro definition by
undefining the macro using `<<#undef isxdigit>>'.
RETURNS
<<isxdigit>> returns non-zero if <[c]> is a hexadecimal digit
(<<0>>--<<9>>, <<a>>--<<f>>, or <<A>>--<<F>>).
PORTABILITY
<<isxdigit>> is ANSI C.
No supporting OS subroutines are required.
*/
#include <_ansi.h>
#include <ctype.h>
#undef isxdigit
int
_DEFUN(isxdigit,(c),int c)
{
return(__ctype_ptr__[c+1] & ((_X)|(_N)));
}
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