how to make a counter in linux?

Question

I'm trying to write a script where I want to make a countdown of three seconds (probably with the sleep command), but every second I want to display the text "break".

After every second, I want to display a countdown next to the word "break", but the line of text should stay in place. The word "break" must stay in one place; only the number should change.

use `printf` with `\r` – Carlos Campderrós Mar 16 '15 at 09:23 — Carlos Campderrós, Mar 16 '15 at 09:23

hek2mgl · Answer 1 · 2015-03-16T10:04:45.893

1

You can use ANSI terminal control sequences. Like this:

# Save the cursor position
echo -en "\033[s";

for i in {3..1} ; do

    echo -n "break $i"
    sleep 1

    # Restore the cursor position
    echo -en "\033[u";

done

# Print newline at the end
echo

If you want the last break 1 to disappear from screen then change the last line to

# Clear the line at the end
echo -en "\033[K"

edited Mar 16 '15 at 10:04

answered Mar 16 '15 at 09:31

hek2mgl

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score 1 · Accepted Answer · answered Mar 16 '15 at 09:31

1

In bash, you can use a for loop, and the character \r to move the cursor back the the beginning of the line:

for ((i=3; i; --i)) ; do
    printf 'break %d\r' $i
    sleep 1
done

answered Mar 16 '15 at 09:31

choroba

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Never seen `\r` used like this, only seen `\r\n` Nice! :) – hek2mgl Mar 16 '15 at 09:34

how to make a counter in linux?

2 Answers2