my $ch = Proc::Background->new(@command);
if (defined $ch->pid()) {
  my $pid = fork();
  if (not defined $pid) {
    die "Cannot fork: $!";
  }
  elsif ($pid == 0) {
    # child process
    my $exitcode = $ch->wait() << 8;
    if ($exitcode == 0) {
      # call URL
    }
  }
  else {
    # parent process
    #waitpid($kidpid, 0); <- do not wait for child
    exit 0;
  }
}
else {
  # failed to execute
  exit 127;
}