An overview of ping

ping-overview.c

// ping.c
int main() 
{
  // ...
  main_loop(icmp_sock, packet, packlen);
}

// ping_common.c
void main_loop(int icmp_sock, __u8 *packet, int packlen) 
{
  // ...
  for (;;) {
    // ...
    if (poll(&pset, 1, next) < 1 || !(pset.revents&(POLLIN|POLLERR)))
      continue;
  }
}