for (my $index=0; $index <= $#$array; $index++){
  defined(my $pid = fork) or die "fork failed: $!";
  unless( defined($pid) ) {
    flock $logfile, LOCK_EX;
    print $logfile "OK $!\n";
    flock $logfile, LOCK_UN;
  }
  unless($pid) { # child
    print "child: $$\n";
    eval {
      .......
    };
    if( $@ ) {
      flock $logfile, LOCK_EX;
      print $logfile "ok";  
      flock $logfile, LOCK_UN;
    }
    unless( .. ) {
      flock $logfile, LOCK_EX;
      print $logfile "ok";
      flock $logfile, LOCK_UN;
    else {
      flock $fh, LOCK_EX;
      print $fh "ok";
      flock $fh, LOCK_UN;
    } 
    close($fh);
    close($logfile);
    exit; # exit child process
  } 
  if(wait() == -1){ 
    print "Parent Process";
    close($fh); # Close file handler $fh
    close($logfile); # Close file handler $logfile    
    alarm(0); 
  } 
}