system('whatever');
if ($?) {
  my $exit_value  = $? >> 8;
  my $signal_num  = $? & 127;
  my $dumped_core = $? & 128;

  print "whatever exited with status $exit_value";
  print " from signal $signal_num"                    if $signal_num;
  print " and dumped core"                            if $dumped_core;
  print "\n";
}