/*  * myspin.c - A handy program for testing your tiny shell  *  * usage: myspin <n> * Sleeps for <n> seconds in 1-second chunks. * */#include <stdio.h>#include <unistd.h>#include <stdlib.h>int main(int argc, char **argv) {    int i, secs;    if (argc != 2) {	fprintf(stderr, "Usage: %s <n>\n", argv[0]);	exit(0);    }    secs = atoi(argv[1]);    for (i=0; i < secs; i++)	sleep(1);    exit(0);}