system('db2', 'LOAD from ...');
if ($? == 0) {
  # all ok
} if ($? & 1) {
  # oops, we didn't select at all?
} if ($? & 2) {
  # just a warning
} if ($? & 4) {
  # execution failed
} if ($? & 8) {
  # command line processor failed
} if ($? & ! 15) {
  # what?
}