Shell 进度条效果的一个实现

#!/bin/bash

processBar()
{
    now=$
    all=$
    percent=`awk BEGIN'{printf "%f", ('$now'/'$all')}'`
    len=`awk BEGIN'{printf "%d", (100*'$percent')}'`
    bar='>'
    for((i=;i<len-;i++))
    do
        bar="="$bar
    done
    printf "[%-100s][%03d/%03d]\r" $bar $len
}

whole=
process=
while [ $process -lt $whole ]
do
    let process++
    processBar $process $whole
    sleep 0.1
done
printf "\n"