src/client/pfs.go
func (c *putFileClient) Close() error {
	_, err := c.c.CloseAndRecv()
	return grpcutil.ScrubGRPC(err)
}
func (c *putFileClient) Close() error {
	_, err := c.c.CloseAndRecv()
	return grpcutil.ScrubGRPC(err)
}
// Close must be called after you're done using a putFileClient.
// Further requests will throw errors.