#include "apue.h"#include <fcntl.h>voidclr_fl(int fd, int flags)				/* flags are the file status flags to turn off */{	int		val;	if ((val = fcntl(fd, F_GETFL, 0)) < 0)		err_sys("fcntl F_GETFL error");	val &= ~flags;		/* turn flags off */	if (fcntl(fd, F_SETFL, val) < 0)		err_sys("fcntl F_SETFL error");}