var net.errInvalidInterfaceName

2 uses

	net (current package)
		interface.go#L22: 	errInvalidInterfaceName     = errors.New("invalid network interface name")
		interface.go#L155: 		return nil, &OpError{Op: "route", Net: "ip+net", Source: nil, Addr: nil, Err: errInvalidInterfaceName}