#include <stdio.h>
#include <stdlib.h>
int main(int argc, char *argv[])
{
int rings;
if(argc != 2) {
printf("Usage: %s number-of-rings
",argv[0]);
return 1;
}
rings = atoi(argv[1]);
printf("Using number-of-rings = %d
", rings);
...
return 0;
}