title: sending signals between father and child is not working
body: <p>Consider the following program where a process father creates a process child , the father should print on the screen 'A' and 'B' , the child writes 'C' and 'D'.
  The problem is that I want the program to ONLY result with 'ACBD'
  This is the code :</p>
  
  <pre><code>void main () {
  int pid;
  signal(SIGUSR1,SIG_IGN);
  if (pid=fork()) {
      printf("A");
      kill(pid,SIGUSR1);
      pause();
      printf("B");
  }
  else {
      pause();
      printf("C");
      kill(getppid(),SIGUSR1);
      printf("D");
  }
  }
  </code></pre>
  
  <p>But its the output is NOTHING !
  Any help would be appreciated !</p>