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cformattingcursor-position

Question about printing: displaying value reflecting change

I have some question about printing on C. Here is my code.

while(1)
{
    if(Button == 32)
    {
        break;
    }
        else
    {
        if(Button == 1)
            count += 1;
        if(btn_value == 2)
            count -= 1;
        if(btn_value == 4)
            count = 0;

        printf("%d\r", count);
        fflush(stdout);
    }
}


for (int i=count;i>=0 ; i--)
{
    printf ("YOUR TIME : %02d\r", i);
    fflush(stdout);
    sleep(1);
}

This is part of my main code. What I designed is to receive button input and change the value of the count correspondingly. What I want to do is to display the value of count in one line that continuously reflects change of count.

I mean, if current situation is

Result window

2

and if I give Button = 1, I want result to be

Result window

3

not

Result window

2
3

So I found some code to do this but when count exceeds 10 and return back to one digit(0~9), the result shows

10 to 90, not 09. Also not 08 but 80. How can I handle this?

Solution

  • You can overwrite leftovers by spaces, like this:

    printf("YOUR TIME : %d \r", i);

    Do you see the space character between %d and \r?

    Some notes:

    • You already had %02d, but this does not match your description of the wrong output.
    • I would place \r at the beginning of the format string, as it seems more logical to me.
    • If the output shall be overwritten with another text after the loop finished, I would keep the \r where it is now, and printf("FINISHED \n"); or puts("FINISHED "); with enough spaces.