#include <stdio.h>
#include <unistd.h> /* for sleep; may be different or unnecessary on your machine */
#define	N	80			/* length of line */

main()
{
	char line[N];			/* background, all blanks */
	char *p;

	/* Initialize the array to all blanks, terminated with a '\0'. */
	for (p = line; p < line + N - 1; ++p) {
		*p = ' ';
	}
	*p = '\0';					/* Put '\0' into line[N - 1]. */

	for (p = line; p < line + N - 3; ++p) {

		/* Erase the last char of the previous rocket, if there was one. */
		if (p > line) {
			p[-1] = ' ';
		}

		/* Draw the rocket. */
		p[0] = '=';
		p[1] = '=';
		p[2] = '>';

		printf("%s\r", line);
		fflush(stdout);
		sleep(1);
	}
}