C printf：在打印文本上方插入行

Question

I want to print with printf above printed lines WITHOUT overwriting old ones. The code below prints

0
1
Hallo
A0
A1
A2
A3
A4

I want the output to be

0
1
Hallo
A0
A1
A2
A3
A4
2
3
4

Is there a possibilty to do this with escape codes (like line up)?

#include "stdio.h" 

#define ANSI_LINE_UP                "\033[3A"


int main() {
    for (int i = 0; i < 5; i++) {
        printf("%d\n", i);
    }

    printf(ANSI_LINE_UP "Hallo\n");
    for (int i = 0; i < 5; i++) {
        printf("A%d\n", i);
    }


    return 0;
}

I use Kubuntu 18.04, if this is relevant.

To make it a bit clearer what I want:

I want to have the output of some printf at the end, so it looks like this:

printf(...) printf(...)

specialprintf(,,,) specialprintf(,,,)

Note: The order of all prints might be different while execution. I just need the normal ones first, then the special ones. If the special ones are in a different order, it is still fine.

This is part of an embedded project. @Arkku solution is good, but I don't quite get it working as I want.

Answer 1

Obviously this depends on what your terminal supports, but in case it supports the \\033[<count>L insertion, it should work as follows:

int main() {
    const int up_lines = 3;
    const int new_lines = 6;

    for (int i = 0; i < 5; ++i) {
        printf("%d\n", i);
    }

    for (int i = 0; i < new_lines; ++i) {
        // make space for existing lines to move down
        putchar('\n');
    }
    // move up and insert the new (empty lines)
    printf("\033[%dA\033[%dL", up_lines + new_lines, new_lines);

    for (int i = 0; i < new_lines; ++i) {
        printf("A%d\n", i);
    }

    // move back down below original lines
    printf("\033[%dB", up_lines);

    return 0;
}

Basically you first make room for the original lines to move down by outputting a number of newlines equal or greater to the number of lines you mean to insert (this step becomes relevant when the terminal position is so near the bottom that the old lines would move off screen). Then you move up to the insertion position (which has now moved by the number of newlines you printed) and insert the number of lines with \\033[<count>L .

edit: Obviously you can repeat this as many times as you like, ie, you don't have to know in advance how many lines you will insert and where, as long as you move back down to the last line after every batch of inserts. For example, you could insert one line at a time by always printing just one newline at the bottom, then moving up to the insertion position (remembering to account for the one line you just added in between), inserting the line there, and moving back down to the bottom.