/* * A clist structure is the head * of a linked list queue of characters. * The characters are stored in 4-word * blocks containing a link and 6 characters. * The routines getc and putc (m45.s or m40.s) * manipulate these structures. */struct clist{	int	c_cc;		/* character count */	int	c_cf;		/* pointer to first block */	int	c_cl;		/* pointer to last block */};/* * A tty structure is needed for * each UNIX character device that * is used for normal terminal IO. * The routines in tty.c handle the * common code associated with * these structures. * The definition and device dependent * code is in each driver. (kl.c dc.c dh.c) */struct tty{	struct	clist t_rawq;	/* input chars right off device */	struct	clist t_canq;	/* input chars after erase and kill */	struct	clist t_outq;	/* output list to device */	int	t_flags;	/* mode, settable by stty call */	int	*t_addr;	/* device address (register or startup fcn) */	char	t_delct;	/* number of delimiters in raw q */	char	t_col;		/* printing column of device */	char	t_erase;	/* erase character */	char	t_kill;		/* kill character */	char	t_state;	/* internal state, not visible externally */	char	t_char;		/* character temporary */	int	t_speeds;	/* output+input line speed */	int	t_dev;		/* device name */};char partab[];			/* ASCII table: parity, character class */#define	TTIPRI	10#define	TTOPRI	20#define	CERASE	'#'		/* default special characters */#define	CEOT	004#define	CKILL	'@'#define	CQUIT	034		/* FS, cntl shift L */#define	CINTR	0177		/* DEL *//* limits */#define	TTHIWAT	50#define	TTLOWAT	30#define	TTYHOG	256/* modes */#define	HUPCL	01#define	XTABS	02#define	LCASE	04#define	ECHO	010#define	CRMOD	020#define	RAW	040#define	ODDP	0100#define	EVENP	0200#define	NLDELAY	001400#define	TBDELAY	006000#define	CRDELAY	030000#define	VTDELAY	040000/* Hardware bits */#define	DONE	0200#define	IENABLE	0100/* Internal state bits */#define	TIMEOUT	01		/* Delay timeout in progress */#define	WOPEN	02		/* Waiting for open to complete */#define	ISOPEN	04		/* Device is open */#define	SSTART	010		/* Has special start routine at addr */#define	CARR_ON	020		/* Software copy of carrier-present */#define	BUSY	040		/* Output in progress */#define	ASLEEP	0100		/* Wakeup when output done */