硬盘保护的一个简单实现，就是发送Idle Immediate命令给硬盘。实际上thinkpad和hp电脑都是通过这个命令，让磁盘磁头立即收回达到保护磁盘的目的-Hard drive protection, a simple implementation, that is to send Idle Immediate command to the hard disk. In fact thinkpad and hp computers through this command, so that an immediate recovery of the disk heads to achieve the purpose of protecting the disk