Question

I am coding a Console Application in c++ and I need to make something like a “loading.gif” just by using ASCII characters.

The following is the list of the characters that I should be using:

1. —
2. \
3. |
4. /
5. —

These symbols will make a loading animation by cycling.

However, when I write the output, it become like:

Output line 1: —
Output line 2: \
Output line 3: |
Output line 4: /
Output line 5: —

I need to do this like this:

Output line 1: [this will be replaced all the time]

It should never go to the second line.

How can I do this in C++? Is there any kind of replace function?

Answer 1

You can use the backspace character ('\b') to go back and overwrite characters on the console. You’ll also need to flush the output after each change, otherwise the output might stay in a buffer and not appear on the console.

Here is a simple example:

#include <iostream>
#include <unistd.h> // for sleep()

int main()
{
    std::cout << '-' << std::flush;
    for (;;) {
        sleep(1);
        std::cout << "\b\\" << std::flush;
        sleep(1);
        std::cout << "\b|" << std::flush;
        sleep(1);
        std::cout << "\b/" << std::flush;
        sleep(1);
        std::cout << "\b-" << std::flush;
    }
}