use POSIX;
if ($pid = fork)
{
   # parent
   do
   {
      local $| = 1;
      print "\b-";  sleep 1;
      print "\b\\"; sleep 1;
      print "\b|";  sleep 1;
      print "\b/";  sleep 1;
      $child_pid = waitpid(-1,WNOHANG);
   }  until $child_pid == -1;
}
else
{
   # child
   #exec("cmd");
   sleep 15;
   exit(0);
}