64  * the same metric and next hop into a common route with a smaller netmask
68  * A route is redundant if and only if any and all routes with smaller
74  * number can be combined into a single route with a coarser mask.
76  * Second, a route can be suppressed in favor of another route with a more
79  * A route must not be suppressed if an incompatible route exists with
80  * an intermediate mask, since the suppressed route would be covered
118 	/* Forget it if this route should not be output for split-horizon. */  in ag_out()
140 	/* Skip it if this route is itself redundant.  in ag_out()
185  *	This must not suppress a route unless it is known that among all
214 			/* Look for a route that can suppress the  in ag_flush()
215 			 * current route */  in ag_flush()
218 				 * another route to work on  in ag_flush()
225 				/* We found a route with a coarser mask that  in ag_flush()
239 				/* If the coarse route has a good enough  in ag_flush()
261 		/* That route has either been output or suppressed */  in ag_flush()
270 /* Try to aggregate a route with previous routes.
321 		 * aggregation table for the new route.  in ag_check()
322 		 * A route to an address less than the current destination  in ag_check()
323 		 * will not be affected by the current route or any route  in ag_check()
358 	/* If we find the even/odd twin of the new route, and if the  in ag_check()
363 	 * the new route must be odd.  However, the second or later  in ag_check()
365 	 * from the even/odd pair of twins of the finer route.  in ag_check()
371 		/* Here we know the target route and the route in the current  in ag_check()
379 			 * route is never promoted until the parent route is  in ag_check()
380 			 * already present.  So we know that the new route is  in ag_check()
381 			 * a promoted (or aggregated) pair and the route  in ag_check()
382 			 * already in the slot is the explicit route.  in ag_check()
384 			 * Prefer the best route if their metrics differ,  in ag_check()
401 			/* Some bits are set if they are set on either route,  in ag_check()
402 			 * except when the route is for an interface.  in ag_check()
415 		 * Any route that can be promoted is always  in ag_check()
436 			 * the route in the slot must be the even twin.  in ag_check()
461 			/* If we cannot combine the pair, maybe the route  in ag_check()
481 			/* The promoted route is even-redundant only if the  in ag_check()
513 			 * The promoted route is odd-redundant only if the  in ag_check()
539 	 * flush the old route in the target slot.  Also flush  in ag_check()
541 	 * the new route.  in ag_check()
572 	/* Save the new route on the end of the table.  in ag_check()
663 /* Tell the kernel to add, delete or change a route
726 			trace_act("route disappeared before" PAT, ARGS);  in rtioctl()
758 #define	    KS_DELETE	0x002		/* need to delete the route */
760 #define	    KS_CHANGE	0x008		/* tell kernel to change the route */
769 	time_t	k_redirect_time;	/* when redirected route 1st seen */
810 /* If a kernel route has a non-zero metric, check that it is still in the
870 /* add a route the kernel told us
950 	/* If it is not a static route, quit until the next comparison  in rtm_add()
966 		msglog("static route %s --> %s impossibly lacks ifp",  in rtm_add()
1080 			msglog("zero length kernel route at "  in flush_kern()
1096 		/* ignore ARP table entries on systems with a merged route  in flush_kern()
1370 	/* If the daemon thinks the route should exist, forget  in kern_out()
1372 	 * If the daemon thinks the route should exist, eventually  in kern_out()
1390 	/* Deleting-and-adding is necessary to change aspects of a route.  in kern_out()
1391 	 * Just delete instead of deleting and then adding a bad route.  in kern_out()
1392 	 * Otherwise, we want to keep the route in the kernel.  in kern_out()
1418 		/* This is an ordinary route, not for an interface.  in walk_kern()
1435 		/* This is an interface route.  in walk_kern()
1457 	/* If RIP is off and IRDP is on, let the route to the discovered  in walk_kern()
1458 	 * route suppress any RIP routes.  Eventually the RIP routes  in walk_kern()
1467 		/* if the route is dead, so try hard to aggregate. */  in walk_kern()
1539 			/* Mark this route to be deleted in the next cycle.  in fix_kern()
1552 /* Delete a static route in the image of the kernel table.
1567 	 * This lets the operator delete a route added by the daemon  in del_static()
1685 /* Find a route to dst as the kernel would.
1695 /* add a route to the table
1750 /* notice a changed route
1759 		/* Fix the kernel immediately if it seems the route  in rtchange()
1760 		 * has gone bad, since there may be a working route that  in rtchange()
1761 		 * aggregates this route.  in rtchange()
1794 /* check for a better route among the spares
1813 /* switch to a backup route
1885 /* Get rid of a bad route, and try to switch to a replacement.
1892 	/* Poison the route */  in rtbad()
1900 /* Junk a RS_NET_SYN or RS_LOCAL route,
1915 		/* Is this the route through loopback for the interface?  in rtbad_sub()
1932 		/* Retain RIPv1 logical network route if there is another  in rtbad_sub()
1947 		/* or if there is an authority route that needs it. */  in rtbad_sub()
1994 	/* Deal with the main route  in walk_bad()
2014 /* Check the age of an individual route.
2027 	/* age all of the spare routes, including the primary route  in walk_age()
2066 	/* finished if the active route is still fresh */  in walk_age()
2073 	/* Delete a dead route after it has been publicly mourned. */  in walk_age()
2079 	/* Start poisoning a bad route before deleting it. */  in walk_age()