NAME
route - manually manipulate the routing tables (Interim)

SYNOPSIS
route [ -n ] [ -q ] [ -v ] command [ [ modifiers ] args ]

DESCRIPTION
Route is a program used to manually manipulate the network routing
tables. It normally is not needed, as the system routing table
management daemon, routed(8), should tend to this task.

Route accepts five commands: add, to add a route, flush, to remove
all routes, delete, to delete a specific route, change, to changes
aspects of a route (such as its gateway), and monitor, to report
any changes to the routing information base, routing lookup misses,
or suspected network partionings.

The monitor command has the syntax
route [ -n ] monitor

The flush command has the syntax
route [ -n ] [ -n ] flush [ family ]

where the address family may be specified by any of the -osi, -xns,
or -inet keywords.

The other commands have the following syntax:

route [ -n ] command [ -net | -host ] destination gateway

where destination is the destination host or network, gateway is
the next-hop gateway to which packets should be addressed. Routes
to a particular host are distinguished from those to a network by
interpreting the Internet address associated with destination. The
optional keywords -net and -host force the destination to be
interpreted as a network or a host, respectively. Otherwise, if
the destination has a "local address part" of INADDR_ANY, or if
the destination is the symbolic name of a network, then the route
is assumed to be to a network; otherwise, it is presumed to be a
route to a host.

For example, 128.32 is interpreted as -host 128.0.0.32, 128.32.130
is interpreted as -host 128.32.0.130; -net 128.32 is interpreted as
128.32.0.0, and -net 128.32.130 is interpreted as 128.32.130.0.

If the route is via an interface rather than via a gateway, the -
interface modifier should be specified; the gateway given is the
address of this host on the common network, indicating the
interface to be used for transmission.

The optional modifiers -xns, and -osi specify that all subsequent
addresses are in the XNS or OSI address families, and the names
must be numeric specifications rather than symbolic names.

The optional -netmask qualifier is intended to acheieve the effect
of an OSI ESIS redirect with the netmask option. One specifies an
additional ensuing address parameter (to be interpreted as a
network mask). One can override the implicit network mask
generated in the inet case by making sure this option follows the
destination parameter.

The optional modifiers -rtt, -rttvar, -sendpipe, -recvpipe, -mtu,
-hopcount, -expire, and -ssthresh provide initial values to metrics
maintained in the routing entry. These may be individually locked
by preceding each such modifier to be locked by the -lock meta-
modifier, or one can specify that all ensuing metrics may be locked
by the -lockrest meta-modifier.

All symbolic names specified for a destination or gateway are
looked up first as a net using getnetbyname(3). If this lookup
fails, gethostbyname(3) is then used to interpret the name as that
of a host.

Route uses a routing socket and the new message types RTM_ADD,
RTM_DELETE, and RTM_CHANGE. As such, only the super-user may
modify the routing tables.

If the flush command is specified, route will "flush" the routing
tables of all gateway entries. One can choose to flush only those
routes whose destinations are of a given address family, by
specifying an optional keyword describing which address family.

The -n option prevents attempts to print host and network names
symbolically when reporting actions. The -v option causes
additional details to be printed. The -q option supresses all
output.

DIAGNOSTICS
"add [ host | network ] %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. If the gateway address used was not the primary address of
the gateway (the first one returned by gethostbyname(3)), the
gateway address is printed numerically as well as symbolically.

"delete [ host | network ] %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.

"Network is unreachable"
An attempt to add a route failed because the gateway listed was not
on a directly-connected network. The next-hop gateway must be
given.

"not in table"
A delete operation was attempted for an entry which wasn’t present
in the tables.

"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.