linux shell 互動, read 命令

read -p "Continue ?(y/n), Please input in 5 seconds " -t 5 -n 1 input
input=`echo "$input" | tr "[:upper:]" "[:lower:]" `
echo -e "\nYour input is '$input'"
if [ "y"x = "$input"x ]; then
    sn=5
    echo "after $sn seconds will do "
    for((i=$sn;i>0;i--));do echo $i; sleep 1;done
    # dorun
else
    echo "exit"
fi