code: func killPrecedessors() error {
  	procs, err := ps.Processes()
  	if err != nil {
  		return err
  	}
  	for _, proc := range procs {
  		walkFn(proc.Pid(), killProc)
  	}
  	return nil
  }
docs: // killPrecedessors will kill any previous "gopass unclip" invokations to avoid
  // erasing the clipboard prematurely in case the the same content is copied to
  // the clipboard repeatedly