| |
| /* |
| FUNCTION |
| <<islower>>---lowercase character predicate |
| |
| INDEX |
| islower |
| |
| ANSI_SYNOPSIS |
| #include <ctype.h> |
| int islower(int <[c]>); |
| |
| TRAD_SYNOPSIS |
| #include <ctype.h> |
| int islower(<[c]>); |
| |
| DESCRIPTION |
| <<islower>> is a macro which classifies ASCII integer values by table |
| lookup. It is a predicate returning non-zero for minuscules |
| (lowercase alphabetic characters), 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 islower>>'. |
| |
| RETURNS |
| <<islower>> returns non-zero if <[c]> is a lowercase letter (<<a>>--<<z>>). |
| |
| PORTABILITY |
| <<islower>> is ANSI C. |
| |
| No supporting OS subroutines are required. |
| */ |
| #include <_ansi.h> |
| #include <ctype.h> |
| |
| #undef islower |
| int |
| _DEFUN(islower,(c),int c) |
| { |
| return ((__ctype_ptr__[c+1] & (_U|_L)) == _L); |
| } |
| |