Re: [libipset] How to read packet counter of a single item?

["U.Mutlu" <um@mutluit.com>]

Jozsef Kadlecsik wrote on 10/13/23 21:05:
> On Fri, 13 Oct 2023, U.Mutlu wrote:
>
>> 1) Which libipset function can be used for getting
>> the packet counter value of a single entry in the set/list?
>>
>> Using the function ipset_parse_line(ips, line) I can issue most of the
>> ipset functions, but I need also a method for getting the packet counter
>> for just a single item only, ie. not the output of all items as "ipset
>> save" does. I need to do this in C/C++ (hence libipset in Linux), ie.
>> not in script.
>
> There is no such functionality in ipset. You can test the existence of an
> element in a set or list/save all of them with all of the attached
> attributes.

I guess you mean just the ipset command line tool, whereas I explicitly stated 
libipset.

After researching it further I think it should be possible to read
the counter of a single item via libipset & co.,
or at least testing the item for having a counter value "gt" etc,
as is already possible in the iptables extensions, ie.
"-m set --packets-gt value" etc.

>> 2) man ipset says
>> "test SETNAME TEST-ENTRY [ TEST-OPTIONS ]
>>     Test whether an entry is in a set or not. Exit status number is zero if the
>> tested entry is in the set and nonzero if it is missing from the set."
>>
>> But the TEST-OPTIONS are not further described or documented.
>> What test options are possible?
>
> There's a single one in the case of list:set: to test the element before
> or after a reference one.

Can you give a practical example for this?