帮助信息似乎不是很丰富：
--list -L [chain [rulenum]]
List the rules in a chain or all chains
--list-rules -S [chain [rulenum]]
Print the rules in a chain or all chains
唯一的区别在于单词的选择：“list”与“print”。
该手册更详细但仍然无济于事：
-L, --list [chain]
List all rules in the selected chain. If no chain is selected, all chains are listed. Like every other iptables command, it applies to the specified table (filter is the default), so NAT
rules get listed by
iptables -t nat -n -L
Please note that it is often used with the -n option, in order to avoid long reverse DNS lookups. It is legal to specify the -Z (zero) option as well, in which case the chain(s) will be atom‐
ically listed and zeroed. The exact output is affected by the other arguments given. The exact rules are suppressed until you use
iptables -L -v
-S, --list-rules [chain]
Print all rules in the selected chain. If no chain is selected, all chains are printed like iptables-save. Like every other iptables command, it applies to the specified table (filter is the
default).
在我看来，这-S实际上更详细，并打印出我通过--dports参数允许的确切端口。但为什么会这样呢？我不认为“打印”这个词会自动暗示比“列表”更高级别的细节？
