CentOS6 root 用户 vi/vim 无法开启高亮

if [ -n "$BASH_VERSION" -o -n "$KSH_VERSION" -o -n "$ZSH_VERSION" ]; then
[ -x /usr/bin/id ] || return
ID=`/usr/bin/id -u`
[ -n "$ID" -a "$ID" -le 200 ] && return
# for bash and zsh, only if no alias is already set
alias vi >/dev/null 2>&1 || alias vi=vim
fi