Question

I have been trying to use fflush to make a progress bar.
To test fflush, I wrote the small code below.

It works as it supposed to when I uncomment “sleep(1);”
but it works in an unexpected way if
it remains commented out. It prints the first dash, waits than prints all remaining
9 of them and quits.

I don’t understand why it makes a difference.

int main()
{
    int f,j;
    j =0;
    for(f=0;f<10;f++)
     {
        printf("-");
        fflush(stdout);
        while(j++<1000000000);
        //sleep(1);
     }
}

Answer 1

Change your for loop like so:

from:

for(f=0;f<10;f++)

to:

for(f=0, j=0; f<10; f++, j=0)