tbd_struct
volatile struct tbd_struct *xmit_buffs[NUM_XMIT_BUFFS];
p->xmit_buffs[i] = (struct tbd_struct *)ptr; /* TBD */
ptr = (char *) ptr + sizeof(struct tbd_struct);
memset((char *)(p->xmit_buffs[i]),0, sizeof(struct tbd_struct));