vif->host_if_name = format (0, "%s%c", host_if_name, 0);
vif->net_ns = format (0, "%s%c", args->host_namespace, 0);
vif->host_bridge = format (0, "%s%c", args->host_bridge, 0);
vif->host_if_name = format (0, "%s%c", host_if_name, 0);
vif->net_ns = format (0, "%s%c", args->host_namespace, 0);
vif->host_bridge = format (0, "%s%c", args->host_bridge, 0);