php在命令行输出进度条

echo "Progress : "; // 5 characters of padding at the end
for ($i=0 ; $i<=100 ; $i++) {
    echo "33[5D"; // Move 5 characters backward
    echo str_pad($i, 3, ' ', STR_PAD_LEFT) . " %"; // Output is always5 characters long
    sleep(1); // wait for a while, so we see the animation
}