The route command is a program used to manually manipulate the
    network routing tables. It normally is not needed, as a system
    routing table management daemon, such as gated or routed, should
    tend to this task.

    The route command accepts these commands:

    add      Adds a route.

    flush    Removes all gateway entries from the routing tables. For
             the inet6 family, it also removes all cloned routes. You
             can choose to flush only those routes whose destinations
             are of a given address family by specifying an optional
             keyword (family) that specifies the address family.

    delete   Deletes a specific route.

    change   Changes aspects of a route (such as its gateway).

    Unless the -net or -host parameters are specified on the
    command line, route creates a host route or a network route by
    interpreting the Internet address associated with destination
    parameter. If the destination has a local address part of INADDR_
    ANY, or if the destination is the symbolic name of a network, a
    network route is created; otherwise, a host route is created.

    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.

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

    Routes added with the route command are marked as RTF_STATIC
    to differentiate them from routes added by the routing daemons
    (gated or routed). The gated daemon does not remove the RTF_
    STATIC routes when it is shut down.

    The route command uses a routing socket and the new message types
    RTM_ADD, RTM_DELETE, and RTM_CHANGE. As such, only a privileged
    user may modify the routing tables.