enum {	MaxEther	= 6,	Ntypes		= 8,}; typedef struct Ether Ether;struct Ether {RWlock;	/* TO DO */	ISAConf;			/* hardware info */	int	ctlrno;	int	tbdf;			/* type+busno+devno+funcno */	int	minmtu;	int	maxmtu;	uchar	ea[Eaddrlen];	int	encry; 	void	(*attach)(Ether*);	/* filled in by reset routine */	void	(*closed)(Ether*);	void	(*detach)(Ether*);	void	(*transmit)(Ether*);	void	(*interrupt)(Ureg*, void*);	long	(*ifstat)(Ether*, void*, long, ulong);	long	(*ctl)(Ether*, void*, long); /* custom ctl messages */	void	(*power)(Ether*, int);	/* power on/off */	void	(*shutdown)(Ether*);	/* shutdown hardware before reboot */	void	*ctlr;	int	pcmslot;		/* PCMCIA */	int	fullduplex;	/* non-zero if full duplex */ 	Queue*	oq; 	Netif;}; extern Block* etheriq(Ether*, Block*, int);extern void addethercard(char*, int(*)(Ether*));extern int archether(int, Ether*);