How can I modify a line which I have already echo it to the screen [duplicate]

Question

When we download something or install software via Terminal, we always see a number show the progress to us.
The number is changed, but it still in the same line.
How can I do in the bash?

I'm a new basher, help!

Answer 1

The trick is to use \r instead of \n at the end of the line:

echo -n " 50% complete."$'\r'; sleep 1; echo "100% complete."

Answer 2

Use echo -n.

More informations on this other post.