netstat without netstat

gistfile1.txt

https://staaldraad.github.io/2017/12/20/netstat-without-netstat/

https://unix.stackexchange.com/questions/131101/without-using-network-command-lines-in-linux-how-to-know-list-of-open-ports-and

# enter as root within docker
dr exec -it -u root:root lab bash

grep -v "grep -v "rem_address" /proc/net/tcp  | awk 'function hextodec(str,ret,n,i,k,c){
    ret = 0
    n = length(str)
    for (i = 1; i <= n; i++) {
        c = tolower(substr(str, i, 1))
        k = index("123456789abcdef", c)
        ret = ret * 16 + k
    }
    return ret
} {x=hextodec(substr($2,index($2,":")-2,2)); for (i=5; i>0; i-=2) x = x"."hextodec(substr($2,i,2))}{print x":"hextodec(substr($2,index($2,":")+1,4))}'