.TH ROUTE 8C "5 May 1983"
.UC 4
.SH NAME
route \- manually manipulate the routing tables
.SH SYNOPSIS
.B /etc/route
[
.B \-f
] [
.I command args
]
.SH DESCRIPTION
.I Route
is a program used to manually manipulate the network
routing tables.  It normally is not needed, as the
system routing table management daemon,
.IR routed (8C),
should tend to this task.
.PP
.I Route
accepts three commands:
.IR add ,
to add a route;
.IR delete ,
to delete a route; and
.IR change ,
to modify an existing route.
.PP
All commands have the following syntax:
.PP
.ti +0.5i
.B /etc/route 
.I command
.B destination gateway
[
.B metric
]
.PP
where
.I destination
is a host or network for which
the route is ``to'',
.I gateway
is the gateway to which packets should be addressed, and
.I metric
is an optional count indicating the number of hops to
the
.IR destination .
If no metric is specified, 
.I route
assumes a value of 0.
Routes to a particular host are distinguished from those to
a network by interpreting the Internet address associated with
.IR destination .
If the 
.I destination
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 
.I metric
should be greater than 0.  All symbolic names specified for a
.I destination 
or 
.I gateway
are looked up first in the host name database,
.IR hosts (5).
If this lookup fails, the name is then looked for
in the network name database,
.IR networks (5).
.PP
.I Route
uses a raw socket and the SIOCADDRT and SIOCDELRT
.IR ioctl 's
to do its work.  As such, only the super-user may modify
the routing tables.
.PP
If the 
.B \-f
option is specified, 
.I 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
application.
.SH DIAGNOSTICS
.B ``add %s: gateway %s flags %x''
.br
The specified route is being added to the tables.  The
values printed are from the routing table entry supplied
in the 
.I ioctl
call.
.PP
.B ``delete %s: gateway %s flags %x''
.br
As above, but when deleting an entry.
.PP
.B ``%s %s done''
.br
When the 
.B \-f
flag is specified, each routing table entry deleted
is indicated with a message of this form.
.PP
.B  ``not in table''
.br
A delete operation was attempted for an entry which
wasn't present in the tables.
.PP
.B ``routing table overflow''
.br
An add operation was attempted, but the system was
low on resources and was unable to allocate memory
to create the new entry.
.SH "SEE ALSO"
intro(4N),
routed(8C)
.SH BUGS
The change operation is not implemented, one should add
the new route, then delete the old one.