367 typedef struct	msgb {  struct
368 	struct	msgb	*b_next;  argument
369 	struct  msgb	*b_prev;  argument
370 	struct	msgb	*b_cont;  argument
371 	unsigned char	*b_rptr;
372 	unsigned char	*b_wptr;
373 	struct datab 	*b_datap;
374 	unsigned char	b_band;
375 	unsigned char	b_tag;
376 	unsigned short	b_flag;
377 	queue_t		*b_queue;	/* for sync queues */