switch + fork

[ogedezvoltare]

ok a have the next code:

      /* we use a fork to create a child process that sniffs the answers */
      switch(pid = fork())
    {
    case -1: 
      pe("Error fork");
      exit(1);
    case 0:
      sniffer(filter,nbr_pkt, 0, dev, resolve);
      exit(1);
      break;
    default:
      /* we wait to let the sniffer starts */
      sleep(1);
      /* we send our packets */
      while (nbr_pkt > 0) {
        if (ack_flag == 1)    
          send_tcp(srcaddr_r, htons(srcport), dstaddr_r, htons(dstport), th_seq, th_ack,  0, ttl, htons(ipid));
        if (syn_flag == 1) {
          th_ack = 0;
          send_tcp(srcaddr_r, htons(srcport), dstaddr_r, htons(dstport), th_seq, th_ack,  1, ttl, htons(ipid));
        }
        --nbr_pkt;    
      }
      /* we start a timer :after 3 seconds, a signal SIGALRM is emitted */
      alarm(3);
      /* we wait for any signal (SIGALRM from hprobe or SIGCHLD from the sniffer) */
      pause();
    }
      exit(0);
    }

what i am interested to knew is what is happened when the exit(1) executes in the child process, why the sniffer isn't stoping and it keeps running, from what i knew the exit() function shall exit from the program, but in this case it is something else, and i don't understand how that is done.
thx. and if you have any questions regarding any another aspect of the program that will help you explain me this statement i will gladly answer

[Silent1Mezzo]

Could you please put your code in [code] brackets to make it more readable...Thanks

[ogedezvoltare]

ok a have the next code:

      /* we use a fork to create a child process that sniffs the answers */
      switch(pid = fork())
    {
    case -1: 
      pe("Error fork");
      exit(1);
    case 0:
      sniffer(filter,nbr_pkt, 0, dev, resolve);
      exit(1);
      break;
    default:
      /* we wait to let the sniffer starts */
      sleep(1);
      /* we send our packets */
      while (nbr_pkt > 0) {
        if (ack_flag == 1)    
          send_tcp(srcaddr_r, htons(srcport), dstaddr_r, htons(dstport), th_seq, th_ack,  0, ttl, htons(ipid));
        if (syn_flag == 1) {
          th_ack = 0;
          send_tcp(srcaddr_r, htons(srcport), dstaddr_r, htons(dstport), th_seq, th_ack,  1, ttl, htons(ipid));
        }
        --nbr_pkt;    
      }
      /* we start a timer :after 3 seconds, a signal SIGALRM is emitted */
      alarm(3);
      /* we wait for any signal (SIGALRM from hprobe or SIGCHLD from the sniffer) */
      pause();
    }
      exit(0);
    }

what i am interested to knew is what is happened when the exit(1) executes in the child process, why the sniffer isn't stoping and it keeps running, from what i knew the exit() function shall exit from the program, but in this case it is something else, and i don't understand how that is done.
thx. and if you have any questions regarding any another aspect of the program that will help you explain me this statement i will gladly answer

I understand now for what is the exit(1) function call, it will generate an SIGCHLD signal that will be caught later in the program with the signal() function.
Now i what to know what is the break instruction roll, and it will ever be executed, if will look that the exit(1) function is just above it?