route - manually manipulate the routing tables
/etc/route [ -f ] [ command args ]
Route is a program used to manually manipulate the network routing
tables. It normally is not needed, as the system routing table manage-
ment daemon, routed(8C), should tend to this task.
Route accepts three commands: add, to add a route; delete, to delete a
route; and change, to modify an existing route.
All commands have the following syntax:
/etc/route command destination gateway [ metric ]
where destination is a host or network for which the route is ``to'',
gateway is the gateway to which packets should be addressed, and metric
is an optional count indicating the number of hops to the destination.
If no metric is specified, route assumes a value of 0. Routes to a
particular host are distinguished from those to a network by interpret-
ing the Internet address associated with destination. If the destina-
tion has a ``local address part'' of INADDR_ANY, then the route is
assumed to be to a network; otherwise, it is presumed to be a route to
a host. If the route is to a destination connected via a gateway, the
metric should be greater than 0. All symbolic names specified for a
destination or gateway are looked up first in the host name database,
hosts(5). If this lookup fails, the name is then looked for in the
network name database, networks(5).
Route uses a raw socket and the SIOCADDRT and SIOCDELRT ioctl's to do
its work. As such, only the super-user may modify the routing tables.
If the -f option is specified, route will ``flush'' the routing tables
of all gateway entries. If this is used in conjunction with one of the
commands described above, the tables are flushed prior to the command's
``add %s: gateway %s flags %x''
The specified route is being added to the tables. The values printed
are from the routing table entry supplied in the ioctl call.
``delete %s: gateway %s flags %x''
As above, but when deleting an entry.
``%s %s done''
When the -f flag is specified, each routing table entry deleted is
indicated with a message of this form.
``not in table''
A delete operation was attempted for an entry which wasn't present in
``routing table overflow''
An add operation was attempted, but the system was low on resources and
was unable to allocate memory to create the new entry.
The change operation is not implemented, one should add the new route,
then delete the old one.
4th Berkeley Distribution 5 May 1983 ROUTE(8C)