chroot(change root)
chroot(change root)功能说明：改变根目录。
语 法：chroot [--help][--version][目的目录][执行指令...]
补充说明：把根目录换成指定的目的目录。
参 数：
--help 在线帮助。
--version 显示版本信息。
chroot
chroot newroot [command]
System administration command. Change root directory for command or, if none is specified, for a new copy of the user's shell. This command or shell is executed relative to the new root. The meaning of any initial / in pathnames is changed to newroot for a command and any of its children. In addition, the initial working directory is newroot. This command is restricted to privileged users.