恢复Debian下root用户bash高亮显示
实际上只需要将ls等命令的--color选项打开即可， 而这些都已存在，只需将~/.bashrc中的注释恢复即可，即下面的蓝色代码：
# ~/.bashrc: executed by bash(1) for non-login shells.
export PS1='\h:\w\$ '
umask 022
# You may uncomment the following lines if you want `ls' to be colorized:
export LS_OPTIONS='--color=auto'
eval "`dircolors`"
alias ls='ls $LS_OPTIONS'
alias ll='ls $LS_OPTIONS -l'
alias l='ls $LS_OPTIONS -lA'
# Some more alias to avoid making mistakes:
alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'
alias vi='vim'