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###VERSION 1.1

VERSION 1.1

###VERSION 1.1

flag() {
    man "$1" | grep -A5 -- "$2";
}

$ flag iptables -t
       iptables [-t table] {-A|-C|-D} chain rule-specification

       ip6tables [-t table] {-A|-C|-D} chain rule-specification

       iptables [-t table] -I chain [rulenum] rule-specification

       iptables [-t table] -R chain rulenum rule-specification

       iptables [-t table] -D chain rulenum

       iptables [-t table] -S [chain [rulenum]]

       iptables [-t table] {-F|-L|-Z} [chain [rulenum]] [options...]

       iptables [-t table] -N chain

       iptables [-t table] -X [chain]

       iptables [-t table] -P chain target

       iptables [-t table] -E old-chain-name new-chain-name

       rule-specification = [matches...] [target]

       match = -m matchname [per-match-options]

       target = -j targetname [per-target-options]

DESCRIPTION
       Iptables  and ip6tables are used to set up, maintain, and inspect the tables of IPv4 and IPv6 packet filter rules in the Linux kernel.  Several different tables may be defined.  Each table contains a
       number of built-in chains and may also contain user-defined chains.

--
       -t, --table table
              This option specifies the packet matching table which the command should operate on.  If the kernel is configured with automatic module loading, an attempt will be made to load the appropriate
              module for that table if it is not already there.

              The tables are as follows:

--
                  This is the default table (if no -t option is passed). It contains the built-in chains INPUT (for packets destined to local sockets), FORWARD (for packets being routed  through  the  box),
                  and OUTPUT (for locally-generated packets).

              nat:
                  This  table is consulted when a packet that creates a new connection is encountered.  It consists of three built-ins: PREROUTING (for altering packets as soon as they come in), OUTPUT (for
                  altering locally-generated packets before routing), and POSTROUTING (for altering packets as they are about to go out).  IPv6 NAT support is available since kernel 3.7.
--
               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]

There is one thing. Now. This function:

flag() {
    man "$1" | grep -- "$2";
}

It works like this:

$ flag iptables -t
iptables [-t table] {-A|-C|-D} chain rule-specification
ip6tables [-t table] {-A|-C|-D} chain rule-specification
iptables [-t table] -I chain [rulenum] rule-specification
iptables [-t table] -R chain rulenum rule-specification
iptables [-t table] -D chain rulenum
iptables [-t table] -S [chain [rulenum]]
iptables [-t table] {-F|-L|-Z} [chain [rulenum]] [options...]
iptables [-t table] -N chain
iptables [-t table] -X [chain]
iptables [-t table] -P chain target
iptables [-t table] -E old-chain-name new-chain-name
target = -j targetname [per-target-options]
-t, --table table
           This  is  the  default table (if no -t option is passed). It
        iptables -t nat -n -L

Well, the last two lines are destroyed.

Anyhow, do you know how to add it to your .bashrc? Do you want it as a script to your ~/bin?

There is one thing. Now. This function:

flag() {
    man "$1" | grep -- "$2";
}

It works like this:

$ flag iptables -t
iptables [-t table] {-A|-C|-D} chain rule-specification
ip6tables [-t table] {-A|-C|-D} chain rule-specification
iptables [-t table] -I chain [rulenum] rule-specification
iptables [-t table] -R chain rulenum rule-specification
iptables [-t table] -D chain rulenum
iptables [-t table] -S [chain [rulenum]]
iptables [-t table] {-F|-L|-Z} [chain [rulenum]] [options...]
iptables [-t table] -N chain
iptables [-t table] -X [chain]
iptables [-t table] -P chain target
iptables [-t table] -E old-chain-name new-chain-name
target = -j targetname [per-target-options]
-t, --table table
           This  is  the  default table (if no -t option is passed). It
        iptables -t nat -n -L

Well, the last two lines are destroyed.

Anyhow, do you know how to add it to your .bashrc? Or do you prefer it as a script to your ~/bin?