ASCII animation

anim.c

/*
 * Copyright (c) 2018 Rudá Moura. All rights reserved.
 */

#include <stdio.h>
#include <unistd.h>
#include <termios.h>
#include <sys/ioctl.h>

void emit(char ch, int n) {
	for (int i=0; i < n; i++)
		putchar(ch);
	putchar('\r');
	fflush(stdout);
}

void toggle(char ch1, char ch2, int n, useconds_t delay) {
	emit(ch1, n);
	usleep(delay/2);
	emit(ch2, n);
	usleep(delay/2);
}

void blink(int n, useconds_t delay) {
	toggle('+', 'X', n, delay);
}

void spin(int n, useconds_t delay) {
	toggle('|', '/', n, delay/2);
	toggle('-', '\\', n, delay/2);
}

int
main(int argc, char *argv[])
{
	struct winsize ws;
	ioctl(STDIN_FILENO, TIOCGWINSZ, &ws);
	int size = (ws.ws_col) * (ws.ws_row);
	for(;;)
		spin(size, 250000);
	return 0;
}