/* FUNCTION <>---control character predicate INDEX iscntrl ANSI_SYNOPSIS #include int iscntrl(int <[c]>); TRAD_SYNOPSIS #include int iscntrl(<[c]>); DESCRIPTION <> is a macro which classifies ASCII integer values by table lookup. It is a predicate returning non-zero for control characters, and 0 for other characters. It is defined only when <>(<[c]>) is true or <[c]> is EOF. You can use a compiled subroutine instead of the macro definition by undefining the macro using `<<#undef iscntrl>>'. RETURNS <> returns non-zero if <[c]> is a delete character or ordinary control character (<<0x7F>> or <<0x00>>--<<0x1F>>). PORTABILITY <> is ANSI C. No supporting OS subroutines are required. */ #include <_ansi.h> #include #undef iscntrl int _DEFUN(iscntrl,(c),int c) { return((_ctype_ + 1)[c] & _C); }