sub write_log {
        my $my_func_id = "write_log";
        print "$my_func_id EVENT_LEVEL: $log{'event_level'}\n" if ($debug eq "1");
        print "$my_func_id LABEL_ID: $label_id\n" if ($debug eq "1");
        print "$my_func_id ROLE_ID: $log{'role_id'}\n" if ($debug eq "1");
        print "$my_func_id FUNC_ID: $log{'func_id'}\n" if ($debug eq "1");
        print "$my_func_id MESSAGE: $log{'message'}\n" if ($debug eq "1");
        my $do_write_log = "INSERT INTO `$log_tbl` (`event_id`, `event_level`, `label_id`, `role_id`, `func_id`,  `message`, `event_date`) VALUES (NULL, '$log{'event_level'}', '$label_id', '$log{'role_id'}', '$log{'func_id'}', '$log{'message'}',  CURRENT_TIMESTAMP);";
        print "$my_func_id QUERY: $do_write_log\n" if ($debug eq "1");
        my $sth0 = $dbh->prepare($do_write_log);
        $sth0->execute();
        $sth0->finish();
}

##</code><code>##

write_log (%log = (
   event_level => 'warning',
   role_id => "$global{$ln}{'role_id'}",
   func_id => $func_id,
   message => "NOTIFY(site or db_user) - @site_entry  EXISTS,ABORTING",
)
);

##</code><code>##

my $rv = $sth->execute();
if (!$rv) {
     write_log (%log = (
          event_level => 'warning',
               role_id => "$global{$dmn}{'role_id'}",
               func_id => $func_id,
               message => "$dbh->errstr",
          )
);

Or like: 
system ("./1_setup_dirs.pl -a $object")
 if ($@) {
        write_log (%log = (
                event_level => 'error',
                role_id => "$global{$dmn}{'role_id'}",
                func_id => $func_id,
                message => "$@",
        )
    );