my $pid = open(PIPE, '-|');
die "open(): $?" unless (defined $pid);
if ($pid) {
    while (<PIPE>) { print $_; }
    close(PIPE);
} else {
    die "system(): $!" unless (system($cmd));
    die "failed to execute: $!" if ($? == -1);
    die "signal: ". ($? & 127) if ($? & 127);
    die "exit code: ". ($? >> 8) if ($? >> 8);
}