| /* |
| FUNCTION |
| <<isalnum>>---alphanumeric character predicate |
| |
| INDEX |
| isalnum |
| |
| ANSI_SYNOPSIS |
| #include <ctype.h> |
| int isalnum(int <[c]>); |
| |
| TRAD_SYNOPSIS |
| #include <ctype.h> |
| int isalnum(<[c]>); |
| |
| |
| DESCRIPTION |
| <<isalnum>> is a macro which classifies ASCII integer values by table |
| lookup. It is a predicate returning non-zero for alphabetic or |
| numeric ASCII characters, and <<0>> for other arguments. It is defined |
| for all integer values. |
| |
| You can use a compiled subroutine instead of the macro definition by |
| undefining the macro using `<<#undef isalnum>>'. |
| |
| RETURNS |
| <<isalnum>> returns non-zero if <[c]> is a letter (<<a>>--<<z>> or |
| <<A>>--<<Z>>) or a digit (<<0>>--<<9>>). |
| |
| PORTABILITY |
| <<isalnum>> is ANSI C. |
| |
| No OS subroutines are required. |
| */ |
| |
| #include <_ansi.h> |
| #include <ctype.h> |
| |
| #undef isalnum |
| |
| int |
| _DEFUN(isalnum,(c),int c) |
| { |
| return(__ctype_ptr__[c+1] & (_U|_L|_N)); |
| } |
| |
