[螺旋线][进度指示]

INTERVAL=0.2
RCOUNT='0'

while :
do
    ((RCOUNT=RCOUNT+1))

    case $RCOUNT in
        1) echo -e '-''\b\c'
            sleep $INTERVAL
            ;;
        2) echo -e '\\''\b\c'
            sleep $INTERVAL
            ;;
        3) echo -e '|''\b\c'
            sleep $INTERVAL
            ;;
        4) echo -e '/''\b\c'
            sleep $INTERVAL
            ;;
        *) RCOUNT='0'
            ;;
    esac
done