在当前用户目录下修改.bashrc

?

# .bashrc

# User specific aliases and functions

alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'

# Source global definitions
if [ -f /etc/bashrc ]; then
        . /etc/bashrc
fi
export HISTTIMEFORMAT="%F %T "

修改用户目录下的.bashrc或者全局的/etc/profile文件，若使其立即生效可以使用
?soucre /etc/profile 
或是 source /home/用户名/bashrc