/proc/net/tcp* would work on linux only.
of course it would be great to have this item implemented for any supported platform.

can you provide some examples of what exactly should be supported ?

Sure

Aim is to have a very efficient way to check for tcp connections. For Linux one could parse files provided by tcp_diag.

46:77D8B85D:9C4C 6A97A345:1770 01 
|  |        |    |        |    |--> connection state
|  |        |    |        |-------> remote TCP port number
|  |        |    |----------------> remote IPv4 address
|  |        |---------------------> local TCP port number
|  |------------------------------> local IPv4 address
|---------------------------------> number of entry

For now I'm used to use vfs.file.regmatch[*]. But that's whether comfortable nor clear to others:

# while IFS=. read a b c d; do printf '%X%X%X%X\n' $d $c $b $a; done <<< 69.163.151.106
6A97A345
# printf '%X\n' 6000
1770

Does any IPv4 connection in any state to or from ip address 69.163.151.106 exist?

vfs.file.regmatch[/proc/net/tcp,6A97A345]

Does any established IPv4 connection to remote ip address 69.163.151.106 and port 6000 exist?

vfs.file.regmatch[/proc/net/tcp,"[[:alnum:]]{8}:[[:alnum:]]{4} 6A97A345:1770 01"]

Now what I like to have is a platform independent way to achieve the same, similar to this:

net.tcp.conn[<lip>,<lport>,<rip>,<rport>,<state>,<mode>]
net.tcp.conn[,,69.163.151.10[678],,established,exist]
net.tcp.conn[,,69.163.151.107,,,count]

Excuse me, please; but at the moment this issue has "Status: Done", but "Resolution: Unresolved".
It's unclear: will this feature request be implemented or not? What is its real state?

Dear constantin.oshmyan, the current ticket is part of main ticket ZBXNEXT-6688 and was closed as completed because ZBXNEXT-6688 was closed.

MVekslers, thank you for explanation!