my $DEBUG_FILE = "log"; # Global

sub debug {
    my ($t) = @_;
    return 0 unless(defined($DEBUG_FILE));
    open my $fh, ">>",$DEBUG_FILE or return 0;
    my $prefix = "[".get_date()."][".basename($0)."](".$$."):";
    print $fh $prefix.$t."\n";
    close ($fh);
    return 1;
}