How to refresh the screen continuously and update it in real time [closed]

Answer 1

To keep it portable across terminal types, you need to use a library such as ncurses. Check out that link, its an exhaustive tutorial.

Here is a basic program that prints an ever increasing number at the top left corner of the screen:

#include 
#include 

int main (void)

{
        /* compile with gcc -lncurses file.c */
        int c = 0;
        /* Init ncurses mode */
        initscr ();
        /* Hide cursor */
        curs_set (0);
        while (c < 1000) {
                /* Print at row 0, col 0 */
                mvprintw (0, 0, "%d", c++);
                refresh ();
                sleep (1);
        }
        /* End ncurses mode */
        endwin();
        return 0;
}

Thats how you refresh the window. Now, if you want to display rows of data as top does, the data you display needs to be maintained in an ordered data-structure (depending on your data, it maybe something as simple as an array or a linked list). You would have to sort the data based on whatever your logic dictates and re-write to the window (as shown in the example above) after a clear() or wclear().