support <size>-1</size> to completely disable the SIZE command

    my $size = $data[0];

    if($size) {

        if($size > -1) {

            print "213 $size\r\n";

            logmsg "SIZE $testno returned $size\n";

        }

        else {

            print "550 $testno: No such file or directory.\r\n";

            logmsg "SIZE $testno: no such file\n";

        }

    }

    else {

        $size=0;

        @data = getpart("reply", "data");