use POSIX ":sys_wait_h";

$SIG{'CHLD'} = \&REAPER;  # manage moribound children
sub REAPER {
  my $pid = 0;

  while (($pid = waitpid(-1, &WNOHANG)) > 0) { $status{$pid} = $?; }

  $SIG{'CHLD'} = \&REAPER;
}