reboot之前忘记从ssh中退出来的同学肯定知道为什么
alias reboot='A="n";read -p "Really want to REBOOT?(y/n)" A;if [[ "$A" = "y" ]];then reboot; fi' alias shutdown='A="n";read -p "Really want to SHUTDOWN?(y/n)" A;if [[ "$A" = "y" ]];then shutdown; fi' alias halt='A="n";read -p "Really want to HALT?(y/n)" A;if [[ "$A" = "y" ]];then halt; fi'