Question

Is it possible to make changes to a line written to STDOUT in shell, similar to the way many programs such as scp do?

The point would be to allow me to essentially have a ticker, or a monitor of some sort, without it scrolling all over the screen.

Answer 1

You can manipulate the terminal with control characters and ANSI escape codes. For example \b returns the cursor one position back, and \r returns it to the beginning of the line. This can be used to make a simple ticker:

for i in $(seq 10)
do
    echo -en "Progress... $i\r"    # -e is needed to interpret escape codes
    sleep 1
done
echo -e "\nDone."

With ANSI escape codes you can do even more, like clear part of the screen, jump to any position you want, and change the output color.