#删除别名设置
[roc@roclinux ~]$ unalias vi

 #删除所有别名
[roc@roclinux ~]$ unalias -a

#再看看, 已经被删除了吧
[roc@roclinux ~]$ alias
alias cp='cp -i'
alias dirA='echo work directory is /root'
alias dirB='echo work directory is $PWD'
alias l.='ls -d .* --color=auto'
alias ll='ls -l --color=auto'
alias ls='ls --color=auto'
alias mv='mv -i'
alias rm='rm -i'
alias which='alias | /usr/bin/which --tty-only --read-alias --show-dot --show-tilde'