// addHistory persists a line of input to the readline history
// file.
func addHistory(ins *readline.Instance, line string) {
// ins.SaveHistory will push command into memory and try to
// persist to disk (if ins's config.HistoryFile is set). err can
// be not nil only if it got a IO error while trying to persist.
if err := ins.SaveHistory(line); err != nil {
log.Warningf("cannot save command-line history: %s", err)
log.Info("command-line history will not be saved in this session")
cfg := ins.Config.Clone()
cfg.HistoryFile = ""
ins.SetConfig(cfg)
}
}
