баян =)
#!/bin/bash
INTERVAL=.5
while true; do
    for i in 1 2 3 4 5 6 5 4 3 2; do
        case $i in
            1)
                echo -ne "\r                        "
                echo -ne "\r[:|:]"
                sleep $INTERVAL
                ;;
            2)
                echo -ne "\r                        "
                echo -ne "\r[:||:]"
                sleep $INTERVAL
                ;;
            3)
                echo -ne "\r                        "
                echo -ne "\r[:|||:]"
                sleep $INTERVAL
                ;;
            4)
                echo -ne "\r                        "
                echo -ne "\r[:||||:]"
                sleep $INTERVAL
                ;;
            5)
                echo -ne "\r                        "
                echo -ne "\r[:|||||:]"
                sleep $INTERVAL
                ;;
            6)
                echo -ne "\r                        "
                echo -ne "\r[:||||||:]"
                sleep $INTERVAL
                ;;
        esac
    done
done






